pre-conference abstract and program volume (large 6mb pdf)

Geologic Problem Solvingwith Microfossils III

Abstracts Volume with Program

proceeds designated forthe Garry Jones and Brian O'Neill Memorial Fund

for NAMS Student Researchan SEPM Foundation Fund

March 10-13, 2013University of Houston, Houston, Texas USA

organized by NAMS-SEPM (North American Micropaleontology Section)

with support from the Society for Sedimentary Geology (SEPM)

Geologic Problem Solving with Microfossils III – University of Houston – March 10-13, 2013

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Geologic Problem Solving with Microfossils III

An international conference organized by NAMS (North American Micropaleontology Section) SEPM

with support from the Society for Sedimentary Geology headquarters (SEPM)

Abstracts with Program March 10 to 13, 2013

University of Houston, Houston, Texas, USA

Proceeds designated for the Garry Jones and Brian O'Neill Memorial Fund for NAMS Student Research, an SEPM Fund

Editors R. Mark Leckie, Pamela Leckie, Andy Fraass, Jason Crux, and Jason Lundquist


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NAMS thanks our conference sponsors for their generous support!

Institutional

Individual

David Watkins Ron Waszczak

Anonymous Jason Crux & Gunilla Gard Nancy Engelhardt-Moore


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NAMS Welcomes You to Houston! It is again with honor and pleasure that I welcome all of you to the third Geologic Problem Solving with Microfossils conference and the second hosted by the University of Houston. This week starts with a fieldtrip to the Cretaceous-Paleogene contact that may be more water proof than the last. This will be followed by two and a half days of oral presentations and poster sessions, and ends with a day and half of workshops and a field trip to view and sample an Eagle Ford Shale outcrop. The week will be filled with numerous talks and posters including sessions on the biostratigraphy of conventional and unconventional reservoirs, paleoenvironments, high-resolution biostratigraphy, environmental modeling, and paleoclimates. This conference, along with its predecessors, has two goals. First we have provided a venue that will promote networking between scientists from different fields asking similar questions from different perspectives about the utility of microfossils. Secondly, all proceeds from this conference will go to the Garry Jones – Brian O’Neill Scholarship Fund. We hope by the end of the meeting you will had the opportunity for professional development, scientific advancement, and by your participation you will have contributed to the sustainability of microfossil studies through building the Jones-O’Neill endowment fund for student support. I wish to thank all of our sponsors and conference participants for their contribution as each sponsor and delegate is making a contribution to the Jones-O’Neill Endowment Fund. Finally, I would like to extend my gratitude and thanks for the outstanding efforts of the whole organizing committee that volunteered their time to make this the largest Geologic Problem Solving with Microfossils conference to date and hopefully by the end of the week we will think of it as the best. Have a great meeting and let’s look forward to even better meetings in the future. Don Van Nieuwenhuise General Chairman Geologic Problem Solving with Microfossils III Conference Organizing Committee


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North American Micropaleontology Section of SEPM President’s Welcome Message

I remember a few years ago at the AAPG in Philadelphia when Ron Waszczak was walking around the Cushman reception handing out NAMS registration forms to every student he saw or suspected. The price was right, and Ron was working the crowd. We have since turned a corner in our student members. As of late 2012, over 20% of our members are students. Students are also contributing significantly to this year’s meeting; over 25% of the registrants are students, many giving oral presentations. Not only are our student participants growing, our overall meeting size has doubled since 2008. One of the major goals of NAMS, one that is actuated through this quadrennial “Geologic Problem Solving with Microfossils” meeting, is to encourage student involvement in the field of micropaleontology. Despite discussion of stagnation in the field, and the lack of funding for basic biostratigraphic studies in favor of (paleo-)oceanographic and ecological research, the enthusiasm for both NAMS and for this conference indicates an upswing in the passion for micropaleontology as a field of investigation for students. Any panel discussion in which I participate generates several enquiries by excited future paleontologists who want to know the where, when, and how of pursuing a career, whether it be academic or industrially-oriented, in their particular field of expertise. I cannot speak to the actual hiring statistics, but from an industry standpoint, it does seem that micropaleontologists are in high demand, both in consultancies and in musical chair major/minor petroleum company positions. NAMS is a multidisciplinary organization that fosters research and collaboration through this conference, by sponsoring the Marine Micropaleontology Research Group Meetings held annually at AAPG, organizing/sponsoring of oral/poster sessions, plus field and short courses, and finally, funding of student travel and research. One problem we do still have, is encouraging students to apply for those annually awarded grants-in-aid. As such, I will unashamedly make a blanket call for applicants, or for encouragement of applicants by their professors. Do watch for the announcements, which are disseminated through NAMS email lists, and newsletter; we want to give out these grants. Alicia Kahn Chevron NAMS President-Elect


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Geologic Problem Solving with Microfossils III

Conference Organizing Committee

Conference General Chair – Donald Van Nieuwenhuise, University of Houston

Conference Committee Co-Chairs – David Watkins, University of Nebraska

and Jason Crux, BHP Billiton

Site Committee Chair – Jason Lundquist, BP America

Housing Committee Chair – Alicia Kahn, Chevron

Sponsorship Committee Chair – Iain Prince, Shell

Food & Entertainment Committee Chair – Nancy Engelhardt-Moore, Ellington and Associates

Technical Sessions Committee Chair – R. Mark Leckie, University of Massachusetts

Courses & Field Trip Committee Chair – Richard Denne, Marathon

Proceedings Volume Committee Chair – Thomas Demchuk, ConocoPhillips

Publicity Committee Chair – Anthony Gary, Energy & Geosciences Institute, University of Utah

Web Site – Pete McLaughlin, Delaware Geological Survey, University of Delaware

NAMS Council President David Watkins, University of Nebraska Secretary Lawrence Febo, BP America Treasurer Donald S. Van Nieuwenhuise, University of Houston President Elect Alicia Kahn, Chevron Past President Jason Crux, BHP Billiton Newsletter Editor Anthony Gary, EGI, University of Utah

SEPM Headquarters Staff Executive Director Howard Harper Associate Director & Business Manager Theresa Scott Publications & Technology Coordinator Michele Tomlinson Membership Services Coordinator Janice Curtis Administrative Assistant Edythe Ellis


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CONFERENCE SCHEDULE

PRE-MEETING FIELD TRIP

Saturday, 9 March 2013 Field Trip 1 K/Pg Boundary in Core and Outcrop 7:00 am – 7:00 pm Leaders: Kirt Campion, John Breyer, Erik Scott, Richard Denne (Marathon Oil)

CONFERENCE AND TECHNICAL PROGRAM

Sunday, 10 March 2013 3:00 – 7:00 pm CONFERENCE CHECK-IN UNIVERSITY OF HOUSTON HILTON HOTEL – 2ND FLOOR MEZZANINE Check in will also be open Monday and Tuesday 7:00 – 9:00 pm ICE-BREAKER and POSTER EXHIBITION HILTON HOTEL – 2ND FLOOR MEZZANINE

Monday, 11 March 2013

ORAL SESSION University of Houston Campus – Science and Engineering Lecture Hall 100 7:15 am Welcome by General Chair 7:30 am Microfossils of Conventional and Unconventional Reservoirs 9:30 am Break with Coffee 11:30 am End of Morning Session 12:00 – 1:15 pm LUNCH: Shamrock Ballroom POSTER EXHIBITION: Conrad Hilton Ballroom 1:30 pm Reconstruction of Past Environments and Biofacies Analysis 3:15 pm Break with Coffee 5:30 pm End of Monday Oral Sessions 6:00 – 8:00 pm: POSTER EXHIBITION AND ICE-BREAKER

Conrad Hilton Ballroom


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Tuesday, 12 March 2013

ORAL SESSION University of Houston Campus – Science and Engineering Lecture Hall 100 7:30 am High Resolution Biostratigraphy, Taxonomy, and Evolution 9:30 am Break with Coffee 11:30 am End of Morning Session 12:00 – 1:15 pm LUNCH: Shamrock Ballroom LAST POSTER EXHIBITION: Conrad Hilton Ballroom Presenters should remove posters between 1:15 and 4:00 pm. 1:30 pm Environmental Monitoring and New Techniques and Technologies 3:15 pm Break with Coffee 5:30 pm End of Tuesday Oral Sessions 7:00 – 10:30 pm EVENING SOCIAL Plenary Dinner With The Dinosaurs Houston Museum of Natural Science, Morian Hall of Paleontology Followed by Lecture in Morian Lecture Hall

“Wildfire Paleoecology on the Cretaceous Coast, Arlington Archosaur Site” Guest Speaker: Derek J. Main Director of the Arlington Archosaur Site, University of Texas at Arlington

Wednesday, 13 March 2013 ORAL SESSION University of Houston Campus – Science and Engineering Lecture Hall 100 7:30 am Microfossils in Paleoclimatology and Paleoceanography 9:30 am Break with Coffee 11:30 am End of Oral Sessions, Farewell From General Chair


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WORKSHOPS

Wednesday, 13 March 2013 1:00 – 5:00 pm Room SEC 201: StrataBugs

Instructors: John Athersuch, Paul Britton, and Rosa Britton. The instructors intend to offer a hands-on session for participants with laptops at the end of their workshop. Room SEC 202: Overview of Paleozoic Microfossils: Conodonts, Graptolites, and Acritarchs Instructors: Daniel Goldman and others.

Thursday, 14 March 2013 8:30 – 11:30 am Room SEC 201: Statistics and Sampling Theory

Instructors: Anthony Gary and Lawrence Febo Room S&R 1 220: TimeScale Creator and the 2012 Time Scale

Instructors: Jim Ogg and Felix Gradstein 1:00 – 5:00 pm Room SEC 202: Palynology for Non-Palynologists

Instructors: Iain Prince and Thomas Demchuk

POST-MEETING FIELD TRIP

Thursday 14 March through Saturday 16 March Field Trip 2: Eagle Ford Shale, Del Rio, Texas, area 1:00 pm Thursday, 14 March – 7:00 pm Saturday, 16 March, 2013 Leaders: Scott Staerker and Lawrence Febo (BP)


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ORAL PROGRAM


Oral Session 1: Microfossils of Conventional and Unconventional Reservoirs University of Houston Science and Engineering Classroom (SEC) Building, Lecture Hall 100

Chairs: Jason Crux (BHP Billiton) and Richard Denne (Marathon) 7:15 Don Van Nieuwenhuise, “Conference Welcome Address”

7:30 J. A. Crux, J. M. Casey and F. J. Peel - Invited Keynote Lecture, “Biostratigraphic Analysis of Mass Transport Deposits and Turbidites in the Lower Miocene of the Gulf of Mexico”

8:00 Richard H. Fillon, “Identifying the Depositional Facies in Reservoir and Resource Play Deposystems: A New Mapping Approach Based on Conventional Biostratigraphic Data”

8:15 Rui Da Gama and Brendan Lutz, “The late Jurassic Garantella and Reinholdella: A paleoenvironmental proxy and potential tool for sweet-spotting in unconventional plays”

8:30 Walter W. Wornardt, “Genetic Sequence Stratigraphic Analysis: Using Calcareous Nannofossil and Planktonic Foraminifers in the Eagle Ford-Austin, and Bossier-Haynesville Formations”

8:45 Richard A. Denne, Russell E. Hinote, Nancy Engelhardt-Moore, and Joan M. Spaw, “Thin Section Foraminiferal Biostratigraphy of the Cenomanian-Turonian Eagle Ford Formation, South Texas”

9:00 Christopher M. Lowery, Matthew Corbett, R. Mark Leckie, David Watkins, T. Scott Staerker, and Art Donovan, “Foraminiferal Evidence of Paleoceanographic Transitions in the Cenomanian-Turonian Eagle Ford Shale Across Southern Texas”

9:15 Khalifa Elderbak, R. Mark Leckie, and Neil E. Tibert, “Paleoenvironmental and paleoceanographic changes across the Cenomanian-Turonian Boundary Event (Oceanic Anoxic Event 2) as indicated by foraminiferal assemblages from the eastern margin of the Cretaceous Western Interior Seaway”

9:30 Coffee Break

10:00 Richard A. Denne, Achim Herrmann, Russell E. Hinote, and Joan M. Spaw, “Multiple ‘Filament’ Events in the Cenomanian-Turonian Eagle Ford of South Texas: Global Correlation and Possible Causal Factors”

10:15 Rui Da Gama and Brendan Lutz, “Biostratigraphic framework and paleoenvironments of the Niobrara Formation: An integrated approach to reservoir characterization”

10:30 Daniel Michoux, “Rig-site palynology and salt tectonics: an example from the Oligocene, offshore West Africa”

10:45 Ryan D. Weber and Lawrence Febo, “Potential industrial applications for nannofossil paleoecological indices on input to deepwater reservoir characterization: examples from Miocene Gulf of Mexico”

11:00 Sarah-Jane Jackett, Rui Da Gama, Brendan Lutz, Zane Jobe, Heidi Albrecht and Tushar Prasad, “Detecting baffle shales using microfossils: An integrated working example from a Miocene GoM development project”


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11:15 Aristóteles de Moraes Rios-Netto, Daniela Santos Machado Brito, Fernanda Silva de Araújo, and Carlos Jorge Abreu, “Foraminiferal Biostratigraphy Helps Understanding of the Evolution of a Quaternary Deep-water Lobe Complex in Campos Basin Brazil”

12:00 Lunch, Conrad Hilton Ballroom – Poster Exhibit Area

Oral Session 2: Reconstruction of Past Environments and Biofacies Analysis University of Houston Science and Engineering Classroom (SEC) Building, Lecture Hall 100

Chairs: Mark Leckie (University of Massachusetts) and David Watkins (University of Nebraska)

1:30 Felix M. Gradstein, I. Davydov and Øyvind Hammer, “Mid-Carboniferous cyclic sedimentation on Bear Island (Arctic Norway)”

1:45 Issam Al-Barram, Randall Penney, and Herve Farran, “Resolving correlation complexity of the Haushi Group, Oman”

2:00 Katrin Ruckwied and Annette E. Götz, “The palynological record of South Africa’s Permian coal deposits: clue to decipher Gondwana’s climate history on high time resolution”

2:15 T. Danelian, A. Zambetakis-Lekkas, G. Asatryan, and A. Grigoryan, “Reconstructing Jurassic and Cretaceous paleoenvironments in Armenia based on Radiolaria and Foraminifera; implications for the geodynamic evolution of the Tethyan realm in the Lesser Caucasus”

2:30 C. J. Schröder-Adams, A.T. Pugh, J. Andrews, J. O. Herrle, J. W. Haggart, M. Hay, D. Harwood and J.M. Galloway, “Contrasting paleoenvironments and paleoproductivity signals in the Upper Cretaceous Boreal Sea: a multi-fossil approach”

2:45 Gerson Fauth, Alessandra da Silva dos Santos, Carlos Eduardo Lucas Vieira, Cristianini Trescastro Bergue, Simone Baecker Fauth, Elizabete Pedrão Ferreira, Marta Cláudia Viviers, Javier Helenes Escamilla, and Marcelo de Araújo Carvalho, “Ostracodes, charophytes and palynomorphs integrated biostratigraphy of the Upper Cretaceous in Santos Basin, Brazil”

3:00 A. T. Pugh, C. J. Schröder-Adams, E. S. Carter, J. O. Herrle, J. W. Haggart, and J. M. Galloway, “Upper Cretaceous Radiolarian Assemblages and Paleoenvironments of the Sverdrup Basin, Ellef Ringnes Island, Nunuvut, Canada”

3:15 Coffee Break

3:45 T. Markham Puckett, “Ostracodes and Plate Tectonics: A Case from the latest Cretaceous of the Caribbean Region”

4:00 Pankaj Khanna and Pramod Kumar, “Characterization of Shell Concentration and Taphonomic Analysis of Maniyara Fort Formation in Kutch Basin, India”

4:15 J. Daneshian and L. Ramezani Dana, “Foraminifera of the Qom Formation as Paleoenviromental indicators in north of Central Iran basin”

4:30 Marie-Pierre Aubry, Don Van Nieuwenhuise, William A. Berggren, Myriam E. Katz, and Kenneth G. Miller, “Neogene Allostratigraphy and Benthic Foraminiferal Biofacies in the Northern Gulf of Mexico along a Depth Transect”

4:45 Nicholas Holmes, Patel Balwant, Nadine Bedayse, Mike Curtis, Roger Kimber, Tim Needham, and Andrew Thurlow, “The role of foraminiferal biofacies in developing a geologically integrated stratigraphic framework for the North Coast Marine area, Trinidad & Tobago”


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5:00 Martin Gross, Werner E. Piller, and Marco Caporaletti, “The ostracod genus Cyprideis (Crustacea) and its implication for Western Amazonia’s palaeoenvironments (Late Miocene; Solimões Formation; Brazil)”

5:15 Ryan Verbanaz and Scott E. Ishman, “Paleoceanographic and paleoglacial reconstruction of Barilari Bay, western Antarctic Peninsula from the benthic foraminiferal record”

5:30 Social Hour and Poster Sessions

Tuesday, 12 March

Oral Session 3: High Resolution Biostratigraphy, Taxonomy, and Evolution University of Houston Science and Engineering Classroom (SEC) Building, Lecture Hall 100

Chairs: Anthony Gary (EGI, University of Utah) and Alicia Kahn (Chevron) 7:30 Bridget S. Wade - Invited Keynote Lecture, “The time has come: Advances in Cenozoic

tropical planktonic foraminiferal biochronology”

8:00 Isabella Raffi, Jan Backman, Domenico Rio, Claudia Agnini, Eliana Fornaciari, and Heiko Pälike, “Biozonation and biochronology of Cenozoic calcareous nannofossils from low and middle latitudes”

8:15 Marie-Pierre Aubry and David Bord, “Back to Basics: Coccolithophores Taxonomy and phylogenetic reconstruction”

8:30 David Bord and Marie-Pierre Aubry, “Morphometric analysis on the Tribrachiatus Lineage: Quantifying morphologic variability during speciation”

8:45 Osman Varol, “New structural observations within Coccolithus, Clausicoccus, Toweius, Prinsius and Reticulofenestra”

9:00 Amy Taylor and Zach Ollerton, “A global perspective on local biostratigraphy: an example from the Scotian Shelf”

9:15 Mike Bidgood and Monika Dlubak, “Large Paleontological Data Sets and the Early History of the South Atlantic”

9:30 Coffee Break

10:00 Paul N. Pearson and Eleanor H. John, “Greenhouse climates, pelagic ecosystems, oxygen minimum zones, and the metabolic hypothesis”

10:15 Maria Rose Petrizzo, Francesca Falzoni, and Brian T. Huber, “Progress in the accuracy and resolution of the Late Cretaceous planktonic foraminiferal biozonation: diversification of Dicarinella and Marginotruncana and biostratigraphic implications”

10:30 Francesca Falzoni, Maria Rose Petrizzo, Brian T. Huber, and Kenneth G. MacLeod, “Santonian–Campanian (Late Cretaceous) planktonic foraminiferal turnover, depth ecology and paleoceanographic implications”

10:45 Shari L. Hilding-Kronforst and Bridget S. Wade, “Revising middle Eocene planktonic foraminiferal bioevents – integrating bio-magneto-chronology”

11:00 R. Mark Leckie, Lyndsey Fox, Andrew Fraass, Richard Olsson, Paul Pearson, Isabella Premoli Silva, Silvia Spezzaferri, and Bridget Wade, “Status and Phylogeny of Paragloborotalia during the Oligocene to early Miocene”


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11:15 Mostafa M. Hamad, “Planktonic foraminiferal biostratigraphy and paleoecology of the Miocene

sequence in the area between Wadi Gharandal and Bir Haleifiya, Gulf of Suez region, Egypt”

12:00 Lunch and Poster Sessions

Oral Session 4: Environmental Monitoring and New Techniques and Technologies University of Houston Science and Engineering Classroom (SEC) Building, Lecture Hall 100

Chairs: Thomas Demchuk (ConocoPhillips) and Iain Prince (Shell) 1:30 Nicolas Barbarin, Luc Beaufort, Yves Gally, and Jean-Marc Moron, “Automated recognition

system of Cenozoïc calcareous nannofossils”

1:45 Gunilla Gard and Anthony Gary, “Automated Fossil Analysis – Advances in Technology Allow for a Paradigm Shift in Biostratigraphic Data Collection and Analysis”

2:00 Andrew J. Fraass, Serena Dameron, Jonathan Dameron, Christopher Lowery, Stephen A. Nathan, and R. Mark Leckie, “FACTbase: A new solution for foram identification”

2:15 A. C. Gary, E. Yu, and G.W. Johnson, “A Web-based Paleoecological Database for Microfossils”

2:30 David H. McNeil, Emily Matys, and Tanja Bosak, “Raman spectroscopic indicators of thermal maturation and graphitization of organic cement in fossil agglutinated foraminifera”

2:45 Christopher James Duffield and Elisabeth Alve, “Feeding habits of deep water benthic foraminifera: An experiment with propagules”

3:00 Kenneth L. Finger, “Benthic foraminifers as paleodepth indicators in the Miocene of Chile: a review of the traditional method and conflicting interpretations”

3:15 Coffee Break

3:45 Malcolm B. Hart and Christopher W. Smart, “Test deformation in foraminifera: variable impacts caused by metal contamination and/or lowered pH in estuarine and marine environments”

4:00 Ali T. Haidar, “Time resolution and trace detection when a distinction between vertical deposition and lateral transport is not possible in the stratigraphic record”

4:15 Lawerence Febo, “Integrated biostratigraphy in shallow geological hazard assessments”

4:30 J. O. Herrle, C. Gebühr, J. Bollmann, A. Giesenberg, and P. Kranzdorf, “Reconstructing Holocene salinity changes in the Aegean Sea using morphological variations of Emiliania huxleyi-coccoliths”

4:45 Sumedh K. Humane, Thierry Adatte, Samaya S. Humane, and Nandeshwar Borkar, “Diatoms and Geochemical Records of anthropogenic impacts in sediments of the Tarna-Satighat Lake, Umrer Taluka, Nagpur District, Maharashtra, India: Implications as indicator of trophic status and land-use change”

5:00 Flavia Fiorini and Stephen W. Lokier, “Changes in benthic foraminifera and sedimentary facies distribution of the Abu Dhabi (UAE) coastline over the last 50 years”

5:15 R. D. Lewis, H. R. Tichenor, O. C. Turner, and J. L. Morgan, “The use of taphonomic grade and biovolume data to supplement relative abundance: Benthic foraminifera from San Salvador, Bahamas”


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5:30 Social Hour and Poster Session

Wednesday, 13 March

Oral Session 5: Microfossils in Paleoclimatology and Paleoceanography

University of Houston Science and Engineering Classroom (SEC) Building, Lecture Hall 100 Chairs: Gunilla Gard (BHP Billiton) and Lawrence Febo (BP America)

7:30 Benjamin Horton - Invited Keynote Lecture, “Microfossils in tidal settings as indicators of

sea-level change, paleoearthquakes, tsunamis and tropical cyclones”

8:00 Martine Boswell, Ben Horton, Steve Culver, Andrew Kemp, Daria Nikitina, Jessica Pilarczyk, and Chris Vane, “Benthic foraminifera from the White Sea, Russia and their implications for high resolution sea-level studies”

8:15 M. A. Godoi, P. L. Gibbard, and M. A. Kaminski, “Correlating shallow marine Holocene records across the Strait of Magellan (53°S), Chile”

8:30 Crystal Pletka and Laurel S. Collins, “Diversity of Caribbean benthic foraminiferal assemblages through the closure of the Central American Seaway”

8:45 Lyndsey Fox, Bridget Wade, Ann Holbourn, and Melanie Leng, “20,000 Forams under the Sea: Reconstructing Climate Variability in the Middle Miocene using Planktonic Foraminifera from the Equatorial Pacific Ocean (IODP Site U1338)”

9:00 Christopher M. Lowery, Emily Browning, R. Mark Leckie, and Cedric M. John, “Foraminifera as Proxies for Miocene Sea Level Change and Sequence Boundaries: Observations from the Marion Plateau, ODP Leg 194”

9:15 Patrick Grunert, Werner E. Piller, and Mathias Harzhauser, “Benthic foraminiferal assemblages reveal the history of the Burdigalian Seaway”

9:30 Coffee Break

10:00 Werner E. Piller, Markus Reuter, Marco Brandano, and Mathias Harzhauser, “Correlating Mediterranean shallow water deposits with global Oligocene–Miocene stratigraphy and oceanic events”

10:15 A. J. P. Houben, S. M. Bohaty, A. Sluijs, and H. Brinkhuis, “Organic-walled dinoflagellate cysts as tracers of oceanographic reorganization in the Southern Ocean before the onset of full-scale Antarctic glaciation”

10:30 Peter K. Bijl, Alexander J. P. Houben, Jörg Pross, Appy Sluijs, Paolo Stocchi, B. L. A. Vermeersen and Henk Brinkhuis, “Relative sea level changes of the Paleogene Southern Ocean inferred from organic-walled dinocysts: a synthesis from ODP Leg 189, Tasmania, Australia”

10:45 Lizette Leon-Rodriguez, Gerald R. Dickens, and R. Mark Leckie, “Carbonate and planktic foraminiferal accumulation in the early Paleogene: The record at ODP Site 1215, eastern equatorial Pacific Ocean”

11:00 Richard H. Fluegeman and Michele A. Chezem, “Foraminiferal paleoecology across the early-middle Eocene transition (EMET) in the western Caribbean”

11:15 Kendra R. Clark, Serena Dameron, and R. Mark Leckie, “Diachroneity and dissolution in the Maastrichtian of Shatsky Rise, NW Pacific”

12:00 End of Oral Sessions


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POSTER PROGRAM

Sunday, 10 March 2013 7:00 pm – 9:00 pm


12:00 pm – 1:15 pm, 6:00 pm – 8:00 pm

Tuesday, 12 March 2013 12:00 pm – 1:15 pm

Poster Area, Conrad Hilton Ballroom, Hilton University of Houston

Poster Group 1: High-Resolution Biostratigraphy, Chronostratigraphy, and Geochronology

1. Erik Anthonissen, “Synchroneity and diachroneity of marine microfossil bioevents: from a high-latitude zonation in the Nordic seas to the low-latitude standard zonations of planktonic foraminifers and calcareous nannofossils”

2. Andrew Fraass, “Preliminary Foram Biostratigraphy and Organic Biomarker Paleotemperature Results from Site U1396, IODP Exp. 340”

3. Ogbaa Nnukwu, “High resolution biostratigraphy and sequence stratigraphic regional correlation of ten wells in the western Niger Delta Basin, Gulf of Guinea”

4. Walter W. Wornardt, “High Resolution Biostratigraphy and Integrated Seismic Sequence Stratigraphic Analysis of the Oxy Alban X1, Adriatic Sea, Offshore Albania”

5. Walter W. Wornardt, “High resolution biostratigraphy and seismic sequence stratigraphic analysis of the Amoco 24-1, North Darag Block, Gulf of Suez Egypt”

Poster Group 2: Reconstructing Past Environments

6. Rebecca Totten Minzoni, “Using Marine Diatoms to Reconstruct Holocene Climate Events and Ice Shelf History: Multi-proxy Investigation of Sediment Cores from Herbert Sound, NE Antarctic Peninsula”

7. Gerald Auer, “High-resolution paleoecological and time-series analyses of an upper Burdigalian upwelling site in the North Alpine Foreland Basin”

8. Tuba Aydin, “Dinoflagellate Cyst Paleoecology, Palynofacies, and Geochemical Paleoenvironmental Analysis of the Maastrichtian Corsicana and Neylandville Formations, Brazos River Section, Texas”

9. Regina Dickey, “Palynology and paleoenvironment of Paleocene-Eocene Wilcox Group sediments in Bastrop, Texas”

10. Vallejo Diego-Felipe, “Middle - late Miocene calcareous nannofossils biostratigraphy and paleoceanography of the Ladrilleros – Juanchaco sequence, Eastern Equatorial Pacific – Colombia”


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11. Virginia Friedman, “Age and Depositional Environment of the lower Eagle Ford Group” 12. Kathryn W. Griener, “Detailed evaluation of several vegetation spikes in the Antarctic Miocene

and their relationship to rapid warming and/or increased precipitation” 13. Kathryn W. Griener, “Nothofagus sporopollenin δ13C indicates decreased moisture availability

in the Antarctic Eocene” 14. O. Salad Hersi, “Age of siliciclastic-dominated Fars Group of the Batina Coast, North Oman,

inferred from bioclastic-bearing carbonate unit” 15. Zuzia Stroynowski, “A Late Pliocene to Present day diatom record from the Bering Sea” 16. Raúl A. Trejos Tamayo, “Middle - late Miocene planktonic foraminifera biostratigraphy and

paleoecology in the Ladrilleros – Juanchaco sequence; (Pacific coast of Colombia)” Poster Group 3: Environmental Monitoring & Ocean Chemistry Proxies

17. M. Drljepan, “Thecamoebians and Tintinnids: Evidence of long-term industrial activity in Sluice Pond, MA”

18. Martin B. Farley, “Teaching Micropaleontology with Data: Gulf of Mexico ‘Dead Zone’” Poster Group 4: Paralic & Lacustrine Micropaleontology

19. Jillian Bambrick Banks, “Paleoclimate of Okak Bay, Labrador, Canada: the intersection of marine, terrestrial, and anthropogenic influences on paleoenvironment”

20. Patrícia P. B. Eichler, “Foraminifera as ecological indicators at Potengi Estuary and adjacent continental shelf (Natal, RN)”

21. R. D. Haselwander, “From water to sediment: preservation potential of organic-walled algae in modern Missouri lakes”

22. Sam Slater, “Palynological analysis of the terrestrial deposits of the Ravenscar Group (Middle Jurassic), northeast Yorkshire, UK”

23. Marissa K. Spencer, “Depositional environment of the Lower Hell Creek Formation: evidence from lithology and palynoflora”

24. Olena Volik, “Non-pollen palynomorphs as proxies of cultural eutrophication of Lake Simcoe, Ontario”

Poster Group 5: Biofacies Analysis: Applications & Challenges

25. R. M. C. H. Verreussel, “Biofacies characterization: the first step towards property prediction in shale gas exploration. An example from the Posidonia Shale in The Netherlands”

Poster Group 6: Paleoclimate, Paleoceanography, & Sea Level

26. Peter K. Bijl, “Tracing the climatic and oceanographic evolution of the early Paleogene Southern Ocean using organic microfossils”


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27. Elizabeth A. Brown, “Geochemical discrepancy in two Globigerinoides ruber (white) morphotypes during the Last Glacial Maximum: implications for paleo-oceanographic reconstruction?”

28. Malcolm B. Hart, “The Holocene separation of Jersey from mainland Europe” 29. Adriane R. Lam, “Planktic Foraminiferal Biostratigraphy and Paleoclimatic Interpretations of

Holocene-Late Pleistocene Core MD02-2535, Tunica Mound, Gulf of Mexico” 30. Di Bella Letizia, “The role of benthic foraminiferal assemblages in the postglacial coastal

evolution: a regional model from the Tyrrhenian basin (Mediterranean).” 31. A. Plata, “Record of diatoms during the middle-late Miocene in Colombian Pacific Coastal,

Ladrilleros-Juanchaco sector, Valle del Cauca” 32. Leah J. Schneider, “Enhanced calcareous nannoplankton productivity during the middle

Miocene transition in the eastern equatorial Pacific (IODP Site U1338)” 33. Shannon Ferguson, “Influence of Climate and Eustacy on Gulf of Mexico Sediment Yield

During the Last Glacial Cycle Based on Palynological Analysis” 34. Stephen Nathan, “The South China Sea: Proto-warm Pool Development and the East Asian

Monsoon” 35. M.L. Thomas, “Modern dinoflagellate cyst distribution in the Gulf of Papua”

Poster Group 7: Taxonomy, Phylogeny, & Evolution

36. Adele Garzarella, “Comparison of evolutionary patterns within genus Discoaster in selected time intervals and correlation to global climate changes”

37. Bobbi Brace, “Evolution of the calcareous nannofossil genus Biscutum in the mid to Upper Cretaceous North American mid-latitudes”

38. Chris Poole, “Getting to grips with a high-resolution biostratigraphic record and the morphological evolution of obscurely-shaped planktonic foraminifera Globigerinoides fistulosus

39. Marina Ciummelli, “New documentation on the distribution range of the genus Catinaster and on its evolutionary relationships”

40. Matthew J. Corbett, “Anagenetic evolution and speciation within the Camplyosphaera eodela-dela clade: A Response to Early Eocene Warming”

41. Zachary A. Kita, “Evolution of the genus Aspidolithus in the Upper Cretaceous Western Interior Basin”

42. Lizette Leon-Rodriguez, “The discovery of tenuitellids from the uppermost Paleocene to middle Eocene in the Equatorial Pacific Ocean, Praetenuitella antica n. sp.: a macro to microperforate planktic foraminifer”

43. Manuel Paez-Reyes, “The Cenozoic gonyaulacacean dinoflagellate genera Operculodinium Wall, 1967 and Protoceratium Bergh, 1881 and their phylogenetic relationships”

44. Dario M. Soldan, “On the phylogeny of Paleogene planktonic foraminifera: wall texture structure and a new genus name for the broedermanni lineage”

45. Osman Varol, “Taxonomic Revision of Helicosphaera and its Contribution to Cenozoic Biostratigraphy”

Poster Group 8: New Technologies & Techniques

46. John Athersuch, “Managing biostratigraphic data with StrataBugs v2.0” 47. Felix M. Gradstein, “Interactive Lithostratigraphic and Biostratigraphic Wallcharts for Offshore

Norway A cooperative project between Norlex and Time Scale Creator”


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48. Felix M. Gradstein, “New Insights with Geologic Time Scale 2012” 49. Christian Haller, “Measuring growth speed and chamber construction in two selected

foraminifera with Micro-CT” 50. Renata M. Mello, “Testing different techniques for microfossil extraction from limestone and

marlstone” 51. John Ortiz, “SDAR a New Quantitative Toolkit for Analyze Stratigraphic Data” 52. Ellen L. Seefelt, “Comparison of three preservation techniques for slowing dissolution of

calcareous nannofossils in organic-rich sediments” 53. Claudia Wrozyna, “Female reproductive morphotypes of Cytheridella ilosvayi Daday, 1905

(Ostracoda, Crustacea) detected by morphological analyses” 54. J.R. Wheeley, “Oxygen isotope variability in Ordovician & Silurian conodonts: validating the

ion-microprobe analysis of individual conodont element

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POSTER AND SPONSOR PROGRAM PLAN PLEASE NOTE THIS PLAN IS AS OF MARCH 1, 2013 AND IS SUBJECT TO CHANGE.

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Geologic Problem Solving with Microfossils III – University of Houston – March 10-‐13, 2013

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Synchroneity and diachroneity of marine microfossil bioevents: from a high-latitude zonation in the Nordic seas to the low-latitude standard zonations of planktonic foraminifers and calcareous nannofossils Erik Anthonissen. Statoil ASA, Svanholmen 8, 4313 Sandnes, Norway. E-mail: [email protected], tel. +47 959 21 567. Synchroneity and diachroneity of marine microfossil bioevents: from a high-latitude zonation in the Nordic seas to the low-latitude standard zonations of planktonic foraminifers and calcareous nannofossils At the global scale, the "standard zonations" for calcareous nannofossils and planktonic foraminifera are arguably the most utilized biostratigraphic frameworks in the petroleum industry. But just how reliable are the numerical ages assigned to these zones and can they be thought as being truly global? As the industry aims towards increasingly challenging exploration targets, are there ways of increasing the resolution of the current biozonations? Recent advances towards an orbitally-tuned global marine composite for the stable isotope records of oxygen and carbon may hold the key. Astronomicaly-tuned isotope records from the Atlantic and Pacific have allowed for 400 kyr eccentricity cycle age-calibration of the Mi, Oi and CM isotope maxima for the Oligocene to Recent interval. This allows identification of additional age-significant climatically-controlled fossil assemblages through calibration to the isotope events. Used within a framework of the standard zonations, this integrated bio-geochemical stratigraphy has the potential to offer improved biostratigraphic resolution in areas where standard markers are in low abundance. At the regional scale, an exercise in the calibration and refinement of the Neogene biostratigraphy of the Nordic Seas highlights the climatic control on pelagic microfossil distributions. The lack of primary and secondary GSSP correlative markers in Neogene deposits of the North Sea, Nordic seas and northern North Atlantic creates a challenge for the biostratigrapher. This study highlights the closest biostratigraphic approximations in this region to the standard chronostratigraphic boundaries of the Geologic Time Scale. Via correlations to key Ocean Drilling studies and unambiguous magnetostratigraphies in the region, the age of shallower deposits of the North Sea has been better constrained. The closest biostratigraphic approximations to these chronostratigraphic boundaries in the region are presented, together with a framework of calibrated events according to sub-basin. The best approximating boundary events at any given location in this region depends upon both the prevailing paleoclimatic and paleoceanographic settings, with the addition of paleobathymetry controlling the benthic foraminiferal markers. An improved, age-calibrated biozonation is presented for the Neogene of the northeastern Atlantic Ocean. This study highlights a best-practices approach for industrial biostratigraphers working in high-latitude regions and across intervals representing times of pronounced provincialism. Here the use of integrated biozones, involving two or more microfossil groups, is necessary for arriving at robust biostratigraphic interpretations. Resolving Correlation Complexity of the Haushi Group, Oman Issam Al-Barram*, Randall Penney, Herve Farran Exploration Department Petroleum Development Oman Email: [email protected] The Haushi Group of Oman subsurface consists of the Al Khlata and Gharif Formations. The Al Khlata Formation, is a Carboniferous to Lower Permian non-marine glacial deposit. It is composed of glacio-fluvial, glacio-lacustrine, and glacio-deltaic successions and holds the second largest oil reserves in south Oman. The Gharif Formation is a Lower to Middle Permian deposit, composed of shallow marine carbonates and clastics in the lower part, and fluvial deposits in the upper. Correlating the Haushi members (reservoirs and seals for exploration; flow units for production) across fields using wireline logs and lithological data alone has always been problematic and tentative. This is primarily due to the rapid lateral variation in lithology particularly in the Al Khlata Formation. Therefore, utilizing palynology is vital to gain a greater accuracy for determining and correlating the Haushi members. A total of six biozones are identifiable in the Haushi Group. This contribution illustrates the strength of palynology in correlating the lithologically heterogeneous Haushi members in wells from northern to central to southern Oman. The Al Khlata Formation members, namely, P9, P5 and P1 are defined by the recognition of the biozones; 2159, 2165 and 2141A/B, respectively. Likewise, recognising the Gharif Formation, is also dependent on the recognition of it’s biozones. The Lower Gharif Member is identified by the 2105 biozone, while the Lower to Middle Gharif is distinguished by the 2190 biozone and the 2252 biozone defines the Upper Gharif Member.


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Interpretation of well data is an interactive process which makes full use of the raw data and supporting schemes. A set of preconfigured interactive charts gives a graphic snapshot of the well or outcrop section. Data entry is facilitated by a ‘scheme picklist’, and many of the data types can be edited directly from the charts – e.g. drag-and-drop interval boundaries. An interactive graphic correlation tool facilitates definition of the age-depth profile (line of correlation), including drag-and-drop nodes for its construction and refinement. Other charts can display biostratigraphic data on age or TVD scales.

A chart showing chronostratigraphic, sequence and event scheme data.

Interactive graphic correlation showing colours from chronostratigraphic scheme

Sequence picks plotted on an age scale – sections of decreasing age are ‘piped’ so that no data are obscured.

Managing Biostratigraphic Data with StrataBugs v2.0 John Athersuch, Paul Britton and Rosa Britton

StrataData Ltd, 17 The Bothy, Ottershaw Park, Surrey UK – KT16 0QG, [email protected] Since the time of William Smith, biostratigraphy has been a key technique for calibrating the stratigraphic record. Advanced computational methods enable huge datasets, typically from industry wellbore samples, to be systematically gathered, organised and manipulated. StrataBugs is the industry-leading tool for the implementation of such procedures, allowing users to probe the stratigraphic record at an ever finer resolution.

In StrataBugs, schemes and dictionaries, including a taxonomic database, stratigraphic schemes and event composite standards, underpin all stratigraphic data. This encourages consistency and standardisation throughout the database and enables events to be correlated between stratigraphic sections. Raw biostratigraphic data is easily entered using a variety of methods, including an on-screen picklist or a touch-screen device. Microscope images can be referenced and stored in the database. A typical workflow might be: enter the raw occurrence data, display the distribution chart and pick events directly from it, use these well events

together with an event composite standard to define the age-depth profile. From this you can generate a preliminary list of biozones, which can be viewed and refined using the chart, alongside other supporting data.


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Neogene Allostratigraphy and Benthic Foraminiferal Biofacies in the Northern Gulf of Mexico Along a Depth Transect Marie-Pierre Aubry(1), Don Van Nieuwenhuise(2), William A. Berggren(1, 3) Myriam E. Katz(4), Kenneth G. Miller(1) (1)Department of Earth and Planetary Science, Rutgers University, 619 Taylor Road, Piscataway, N J 08554. [email protected], Ken Miller <[email protected]> (2) Department of Earth Sciences, Houston University, Houston, TX <[email protected]> (3)Department of Geology and Geophysics, woods Hole Oceanographic Institution, Woods Hole Ma 02536 [email protected] (3) 1W08 JRSC, Earth & Environmental Sciences, Rensselaer Polytechnic Institute, 110 8th St. Troy NY 12180 Mimi Katz <[email protected]>

We present an integrated Neogene biostratigraphic study of planktonic foraminifera and calcareous nannofossils from a >600 km long, NE-SW transect including several wells, taken between 92m water depth and 482m water depth in the northern Gulf of Mexico. Sample material consists of ditch cuttings (with ~ 30’ to 60’ resolution) and sidewall cores. We determine the relative completeness of the Neogene stratigraphic succession by analyzing the sedimentary history in each well using magnetobiochronologically calibrated datum events of selected calcareous plankton (see Aubry, 1995). The hiatuses associated with inferred unconformities and the age of their bounding surfaces are calculated, estimated or, when (data are insufficient) approximated. Multiple unconformities are recognized in all wells studied here, and corresponding intra-Neogene hiatuses range from ~ 1 to 3 Myr; a lower Miocene/Oligocene unconformity has a duration of ~ 10 Myr. The unconformity-bounded sedimentary packages roughly correspond to the third order cycles of sequence stratigraphy. However, unlike the premises of sequence stratigraphy the unconformities have no chronostratigraphic significance in this allostratigraphic architecture. We determine that late Miocene-Pleistocene hiatuses and rates of sedimentation increase with depth along the transect, contrary to predictions based on a “sedimentary sequence”, the basic model of sequence stratigraphy, but consistent with our observations in the DeSoto Canyon (Aubry, 1993). The allostratigraphic framework described here serves as a framework for the delineation of Neogene neritic to upper bathyal benthic foraminiferal biofacies, paleobathymetry and paleoenvironments. Benthic foraminiferal faunas indicate that Neogene paleodepths were slightly shallower at the eastern wells, and deepened towards the western wells. Miocene sediments are thickest in the central and eastern portions of the transect. The western wells

Three biostratigraphic data charts showing (a) individual species with age range demonstrated using chronostratigraphic scheme and composite standard; (b) occurrences grouped by category and displayed as in separate tracks and (c) stacked curves showing relative abundance.


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accumulated greater thicknesses during the Plio-Pleistocene, indicating a shift in the depocenter. Thus, accommodation and sediment supply were greater in the west, while progradation in the east resulted in shallower paleodepths. Biofacies changes through time provide important information about paleo-environments. Calcareous benthic foraminiferal biofacies dominated by Uvigerina spp., along with occurrences of a distinctive assemblage of agglutinated foraminifera (known from the "Agua Salada Fauna"), indicate that paleoenvironments characterized by low-oxygen conditions occurred periodically through the studied sections. These conditions began by the late Early Miocene at some locations. Intensified low-oxygen environments became evident at all wells by the Late Miocene. In Upper Miocene-Pliocene sediments, oxygen levels appear to have been related to paleodepth, indicating that the development of lower oxygen conditions was the result of an expansion or migration of the oxygen minimum zone.

Aubry, M.-P., 1993. Neogene allostratigraphy and depositional history of the De Soto Canyon area, northern Gulf of Mexico.

Micropaleontology, v. 39(4), p. 327-366. Aubry, M.-P., 1995. From chronology to stratigraphy: Interpreting the stratigraphic record. In Berggren, W. A., Kent, D. V., Aubry,

M.-P., and Hardenbol, J. (eds), Geochronology, Time scales and Global Stratigraphic Correlations: A Unified Temporal Framework for an Historical Geology. Society of Economic Geologists and Mineralogists Special Volume N° 54, p. 213-274.

Back to Basics: Coccolithophores Taxonomy and Phylogenetic Reconstruction Marie-Pierre Aubry and David Bord Department of Earth and Planetary Science, Rutgers University, 619 Taylor Road, Piscataway, N J 08554. [email protected], David Bord <[email protected]> Sound taxonomic frameworks are of paramount importance in determining evolutionary patterns through time and deciphering their implications for understanding the major events that have punctuated Earth history. The use of molecular biology for determining natural groupings (orders and families) among the living coccolithophores has been critical in validating the morphostructural approach to coccolithophore taxonomy, and lends strong support to the classification of the Cenozoic Coccolithophores into five extant and five extinct orders, and 46 families (including Incertae Sedis). We highlight: 1) the recent introduction of the Order Biscutales and 2) Order Braarudosphaerales, and 3) a thorough revision of the Order Discoasterales to which the Middle Eocene genus Nannotetrina, long considered Incertae sedis, is now ascribed. A complete taxonomic revision entitled Cenozoic Coccolithophores in 24 volumes is scheduled for publication during the next two years. Cenozoic Coccolithophores provides a hierarchy of taxonomically significant characters that are used, in turn, to trace the roots of the Cenozoic coccolithophores into the Mesozoic. Whereas it has generally been considered that most orders of Coccolithophores became extinct at the Cretaceous/Paleogene (K/P) boundary (66 Ma), we trace the origin of all Cenozoic orders to the early Mesozoic. Several Mesozoic orders, however, became extinct in the Late Cretaceous. In contrast, few families range through the K/P boundary. We illustrate and discuss here two orders: the Order Braarudosphaerales, which is one of the very first orders to be represented in the Upper Triassic sedimentary record, and the Order Discoasterales whose Cretaceous radiation resulted in a diversification as broad as during the early Cenozoic. Aubry, M.-P., 2012. Cenozoic coccolithophores. New York: Micropaleontology Press. Atlas of Micropaleontology series. High-Resolution Paleoecological and Time-Series Analyses of an Upper Burdigalian Upwelling Site in the North Alpine Foreland Basin Gerald Auer1, Werner E. Piller1, Mathias Harzhauser2, Stjepan Ćorić3, Patrick Grunert1

1Institute for Earth Sciences (Geology and Palaeontology), Graz University, Heinrichstrasse 26, 8010 Graz, Austria, [email protected] 2Naturhistorisches Museum Wien, Geologisch-Paläontologische Abteilung, Burgring 7, 1014 Wien, Austria 3Geological Survey of Austria, Neulinggasse 38, 1030 Vienna, Austria A high-resolution analysis was performed on late Burdigalian (CNP-zone NN4) shallow neritic sediments from the North Alpine Foreland Basin in Lower Austria. Focussing on the rapidly changing environmental conditions in connection with the onset of the Middle Miocene Climate Optimum (MMCO) a section of 940.5 mm was continuously sampled yielding 100 samples covering a thickness of ≤1 cm each. Based on estimated sedimentation rates the studied section represents a timespan of ~1,600 years. To these samples an integrated approach was applied to study proxy records including calcareous nannoplankton, geochemical and sedimentological data. This study is the first attempt to analyse outcrop data on such a high resolution, sub-Milankovitch scale with respect to calcareous nannoplankton in conjunction with geochemical and sedimentological data. Our results indicate that


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changes in coccolith abundances as well as in organic carbon and sulphur contents are linked to the changing local environmental conditions. These include variations in water-column stratification, primary productivity, organic matter flux, bottom-water oxygenation and changes in relative sea level. Time-series analyses on these proxies using REDFIT-analysis and Wavelet spectra hint at the influence of solar-cycles on local climate variation. A best-fit adjustment of assumed sedimentation rates results in cycles fitting the lower (~65 y) and upper (~113 y) Gleissberg-cycle as well as the Suess-cycle (~211 y). This is the first such high-resolution analysis performed on a marine succession of late Burdigalian age. Previous multi-proxy investigations of lacustrine Late Miocene sediments based on geochemical data, pollen and dinoflagellates also yielded robust results for the reconstruction of high-resolution climate variability on a decadal to centennial to millennial scale (Gross et al. 2011; Kern et al., 2012). Gross, M., Piller, W.E., Scholger, R., Gitter, F., 2011. Biotic and abiotic response to palaeoenvironmental changes at Lake Pannons'

western margin (Central Europe, Late Miocene). Palaeogeography, Palaeoclimatology, Palaeoecology 312, 181–193. Kern, A.K., Harzhauser, M., Piller, W.E., Mandic, O., Soliman, A., 2012. Strong evidence for the influence of solar cycles on a Late

Miocene lake system revealed by biotic and abiotic proxies. Palaeogeography, Palaeoclimatology, Palaeoecology 329-330, 124–136.

Dinoflagellate Cyst Paleoecology, Palynofacies, and Geochemical Paleoenvironmental Analysis of the Maastrichtian Corsicana and Neylandville Formations, Brazos River Section, Texas Tuba Aydin 1, John V. Firth 2, Thomas E. Yancey 1 1 Department of Geology& Geophysics, Texas A&M University, College Station, TX 77843, USA 2 Ocean Drilling Program, 1000 Discovery Drive, Texas A&M University Research Park, College Station, TX 77845, USA. E-mail address: [email protected] Maastrichtian sedimentary deposits of the Corsicana Formation and Neylandville Formation exposed along on the Brazos River, Texas have been studied with a multi-proxy approach for determination of the paleoenvironmental events recorded during the Maastrichtian. The study area is located on the northwestern margin of the Gulf of Mexico, offshore from the Llano uplift of Central Texas. Samples collected upstream and downstream of the Route 413 Bridge near Highbank, Texas on the Brazos River yielded abundant dinoflagellate assemblages. Marker horizons in the section include a thin (0.3m) cemented sandstone in the middle of the Corsicana Formation and the Nacatoch Formation sandstone separating the Corsicana and Neylandville formations. The following biostratigraphically useful dinoflagellate species are identified Disphaerogena carposphaeropsis, Hafniasphaera spp., Cerodinium diebelii, Thalassipora pelagica and Cordosphaeridium fibrospinosum, Deflandrea galeata, Chatangiella decorosa, Isabelidinium sp. and Xenascus ceratiodies. Preliminary data for the study shows that the percent marine/terrestrial ratio for overall samples is low except for two peak abundances of marine dinoflagellate cysts (a) immediately below and about 17 m. (b) below the K-Pg boundary. Dinoflagellate assemblages mostly dominated by Gonyaulacoid cysts, containing either abundant Glaphyrocysta spp. or abundant Spiniferites spp. One sample is dominated by Peridinoid cysts (Cerodinium spp.) (Table 1). Dinoflagellate cyst assemblages are also supplemented by δ18O and δ13C (benthic foraminifera) stable isotopes and TEX86 sea-surface temperature proxy. Paleoclimate of Okak Bay, Labrador, Canada: The Intersection of Marine, Terrestrial, and Anthropogenic Influences on Paleoenvironment Jillian Bambrick Banks*, Dr. Samuel Bentley, and Dr. Sophie Warny Louisiana State University Department of Geology & Geophysics (*[email protected]) Marine and terrestrial settings along the North Atlantic coastline have undergone severe environmental fluctuations in the wake of post glacial climate change throughout the Quaternary. Okak Bay (Figure 1), an embayment along the northern Labrador coast, is especially sensitive to such climate changes because of its location adjacent to the Labrador Sea where North Atlantic currents originate (Marshall and Schott, 1999), and near the current position of the latitudinal tree line (Elliott and Short, 1979). This seasonally anoxic fjord-like bay has the potential of having a relatively high sedimentation rate, as evidenced from similar fjords to the North (Bentley and Kahlmeyer, 2012; Huelse and Bentley, 2012), and the region has served as home for numerous prehistoric and historic populations over the past 7000 years (Fitzhugh, 1972; Curtis, 2007). For these reasons, this site provides a unique record to analyze climate change and anthropogenic influence, which should reflect fluctuations in both terrestrial and marine contexts at a high-resolution scale throughout the late Holocene.


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Previous palynological investigations of pond sediments in central-northern Labrador have shown a clear vegetation response to fluctuating cooling and warming trends over the past 10,000 years (Wenner, 1947; Short and Nichols, 1977; Short, 1978). Additionally, a recent survey of dinoflagellate cysts

from surface sediments of Okak Bay revealed a transitional assemblage characteristic of a fjord driven more by sea-surface salinity and temperature rather than sea-ice conditions (Richerol et al, 2012). With these previous studies in mind, this investigation sets out to address 4 main research questions: (1) how have the sea surface conditions in Okak Bay changed over the past several thousand years, (2) how has the vegetation in the Okak region responded to climate change in the same period, (3) how have these environmental conditions affected human settlement in the Okak region, and (4) is there evidence for anthropogenically induced environmental change recorded in Okak Bay. To answer these questions, this study will focus on environmental proxies such as microfossils (mainly pollen, spores, and dinoflagellate cysts) and sedimentological characteristics (density, magnetic susceptibility, grain size, elemental distribution) from sediment cores retrieved from Okak Bay to determine the marine and terrestrial signatures of climate change and potential anthropogenic influence throughout the late Holocene. Preliminary microfossil data indicate that the base of the core is dominated by tree/shrub genera Betula and Alnus, while the surface sediments at the top contain a much higher abundance of conifer genera (i.e. Picea) and dinoflagellate cysts, reflecting an overall shift in environmental conditions over the past several thousand years. Bentley, S.J., and Kahlmeyer, L. 2012. Fluvial sediment flux and dispersal in two subarctic fjords: Nachvak and Saglek Fjords,

Nunatsiavut, Canada. Canadian Journal of Earth Science, v. 29(10), pp. 1200-1215. Curtis, J. 2007. Archaeological Assessments in Northern Labrador. In Provincial Archaeology Office 2006 Archaeology Review,

volume 5. Government of Newfoundland and Labrador, Department of Tourism, Culture, and Recreation. Elliott, D.L., and Short, S.K. 1979. The Northern Limit of Trees in Labrador: A Discussion. Arctic, v. 32(3), pp. 201-206. Fitzhugh, W.W. 1972. Environmental Archaeology and Cultural Systems in Hamilton Inlet, Labrador: A Survey of the Central

Labrador Coast from 3000 B.C. to the Present. Smithsonian Institution Press, Washington. Hulse, P., and Bentley, S.J. 2012. A Holocene sedimentary record of climatically force river-discharge variations on the subarctic

Labrador Coast, Canada. In review, Holocene. Marshall, J., and Schott, F. 1999. Open-Ocean Convection: Observations, Theory, and Models. Reviews of Geophysics, v. 37(1),

pp. 1-64. Richerol, T., Pienitz, R., and Rochon, A. 2012. Modern dinoflagellate cyst assemblages in surface sediments of Nunatsiavut fjords

(Labrador, Canada). Marine Micropaleontology, v. 88-89, pp. 54-64. Short, S.K. 1978. Palynology: a Holocene environmental perspective for archaeology in Labrador-Ungava. Arctic Anthropology, v.

15(2), pp. 9-35. Short, S.K., and Nichols, H. 1977. Holocene pollen diagrams from subarctic Labrador-Ungava: vegetational history and climate

change. Arctic and Alpine Research, v. 9(3), pp. 265-290. Wenner, C.G. 1947. Pollen diagrams from Labrador. Geografiska Annaler, v. 29, pp. 137-374.

Automated Recognition System of Cenozoic Calcareous Nannofossils Nicolas Barbarin1, Luc Beaufort1, Yves Gally1, Jean-Marc Moron2 1CNRS-CEREGE, UMR 6635, BP 80, Europôle de l’Arbois, 13545 Aix-en-Provence cedex 04, France 2TOTAL, Centre Scientifique et Technique Jean-Féger, Avenue Larribau, 64018 Pau Cedex, France Contact: [email protected] Calcareous nannofossils are microscopic-scaled plates (mainly coccoliths) produced by marine phytoplankton. They are abundant in marine sediment, very diversified through geologic time and sensitive to climatic/environmental changes. This is why they are very used in biostratigraphy and paleoceanographic reconstructions. In some specific sedimentary environment but important for the industry they can be not abundant enough for a rapid biostratigraphic expertise. The use of the automated recognition would detect relevant specimens in a large number of non-coccolith microscopic objects, a work that is usually tedious of specialists. The actual automated system SYRACO (SYstème


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de Reconnaissance Automatisée des COccolithes) based on artificial neural networks is able to recognized ten Upper Pleistocene species (Dollfus and Beaufort, 1999; Beaufort and Dollfus, 2004) and therefore not applicable for biostratigraphy. We present here important improvement of SYRACO which is now able to detect most of the coccoliths belonging to thousand of species produced since the Upper Eocene. The system combines neural networks based on a large database and statistical classifications on morphometric measurements (expert systems). The system is able to filter around 90% of the non-nannofossils and keep between 90 and 75% of the nannofossils. The system lumps detected images and measurement in about 30 classes. The specialist is able to look at those images to rapidly identify target species for biostratigraphic study. We present here an example of paleoceanographic and biostratigraphic applications on the core MD052930 covering the last 800 kyrs in the Gulf of Papua. The results show a good estimation of abundances of the main groups that allow not only paleoecologic studies but also permit to perform fast and precise quantitative biostratigraphy. Beaufort, L., Dollfus, D., 2004. Automatic recognition of coccoliths by dynamical neural networks. Marine Micropaleontology 51, 57-

73. Dollfus, D., Beaufort, L., 1999. Fat neural network for recognition of position-normalised objects. Neural Networks 12, 553-560. Large Paleontological Data Sets and the Early History of the South Atlantic Mike Bidgood and Monika Dlubak Neftex Petroleum Consultants Ltd., 97 Milton Park (2nd Floor), Abingdon, Oxfordshire, OX14 4RY, United Kingdom [email protected] [email protected] The use of large and disparate paleontological data sets from the circum South Atlantic to form a coherent geological history is hampered by taxonomic inconsistencies, restricted perspectives and uncalibrated event timings. Using several hundred pieces of public domain paleontological data from South America (Campos and Santos Basins, Brazil) and Southwest Africa (West-central Coastal and Orange River Coastal Basins), we have calibrated over 17,000 individual bioevents from a large range of fossil groups to global standard biozones. This leads to re-evaluation and improved geological understanding at the regional scale. As a result key local biostratigraphic events have been compiled in a separate synthesis events scheme, allowing creation of synthesis biozones. In the Campos & Santos Basins we demonstrate how changes in biostratigraphic assemblages from exclusively lacustrine (fresh water ostracods) to, eventually, a fully marine fauna by the mid-Cretaceous helps to constrain geodynamic and paleoenvironmental interpretations. These changes are also present on the west African conjugate margin. South of the Walvis Ridge events have a somewhat different timing and style with organic rich sediments being developed earlier and transgressed during the mid Barremian until full breaching occurred in the Albian. These biostratigraphic schemes erected around the South Atlantic margin help clarify the early evolution of the ocean, and bring new regional perspectives to local exploration plays, despite the relatively poor existing biostratigraphic data coverage. Collation of a large volume of data across a range of fossil groups allows us to produce a coherent biostratigraphic synthesis, refining our understanding of regional-scale geological evolution, improving efficiency and reducing risk in resource exploration. Tracing the Climatic and Oceanographic Evolution of the Early Paleogene Southern Ocean Using Organic Microfossils Peter K. Bijl1, Alexander J.P. Houben1, Francesca Sangiorgi1, Jörg Pross2, Appy Sluijs1 and Henk Brinkhuis1, 3 1Department of Earth Sciences, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, 3584 CD Utrecht, the Netherlands 2Paleoenvironmental Dynamics Group, Institute of Geosciences, Frankfurt University, Altenhöfer Allee 1, 60438 Frankfurt, Germany 3NIOZ Royal Netherlands Institute of Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, the Netherlands The Paleogene ‘Greenhouse-Icehouse’ transition is one of the worlds major transitions, from ice-free polar regions until somewhere in the Eocene (~40-34 million years ago; Ma), to a fully glaciated Antarctica from 34 Ma onwards. The difficulty of reconstructing forcing factors, biotic response and climatologic consequences of such a transition lies in the scarcity of continuous records from close to the Antarctic continent, the poor chronostratigraphic control on the


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records that are available, and the paucity of tools to reconstruct paleoenvironmental change. Organic-walled dinoflagellate cysts have proven to preserve well in high-latitude sediments, and therewith not only provide a valuable too for biostratigraphy in the Southern Ocean, but also it provide a means evaluate paleoenvironmental change in very high detail. Recently, IODP Leg 318 recovered an unprecedented, well-dated Cenozoic sedimentary record from the Wilkes Land Margin of Antarctica. Much of the record lacks carbonate and silicate microfossils, but well-preserved assemblages dinocysts allow for the reconstruction of major climatological and oceanographic changes. Early Eocene (~53-51 Ma) dinocyst assemblages are dominated by cosmopolitan taxa, indicating warm, ice-free conditions. Tropical dinocysts dominate the assemblages, and together with the organic geochemical proxy for sea surface temperature, they reveal tropical sea surface temperatures. This nicely corroborates with the pollen-derived air temperature reconstructions, suggesting Antarctic summer temperatures exceeding 23 C during the early Eocene, which sustained the presence of palms and bombacaceae trees on the Antarctic coastline. During the middle Eocene (50 Ma onwards) Antarctic vegetation consists of species with a higher cold tolerance, and dinocyst assemblages are characterized by endemic taxa, while other regions in the Southern Ocean are continuously dominated by cosmopolitan taxa. This distinct difference in dinocyst assemblage is not only a perfect tracer for specific oceanographic regimes, they also reveal that a connection developed between the Australo-Antarctic Gulf and the Pacific Ocean, signifying a shallow-water opening of the Tasmanian Gateway around 50 Ma. Towards the Oligocene, the Southern Ocean progressively cools, ultimately leading up to the onset of continental-scale glaciations on Antarctica in the earliest Oligocene. Combined with organic geochemical tools, dinocyst assemblages portray a coherent and consistent view of paleoenvironmental and oceanographic changes around Antarctica, which have significance for the global temperature evolution of that time. Relative Sea Level Changes of the Paleogene Southern Ocean Inferred from Organic-Walled Dinocysts: A Synthesis from ODP Leg 189, Tasmania, Australia Peter K. Bijl1, Alexander J.P. Houben1, Jörg Pross2, Appy Sluijs1, Paolo Stocchi3, B.L.A. Vermeersen3 and Henk Brinkhuis1, 3

1Department of Earth Sciences, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, 3584 CD Utrecht, the Netherlands 2Paleoenvironmental Dynamics Group, Institute of Geosciences, Frankfurt University, Altenhöfer Allee 1, 60438 Frankfurt, Germany 3NIOZ Royal Netherlands Institute of Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, the Netherlands The Paleogene ‘Greenhouse-Icehouse’ transition is one of the worlds major transitions, from ice-free polar regions until somewhere in the Eocene (~40-34 million years ago; Ma), to a fully glaciated Antarctica from 34 Ma onwards. The presence of ice prior to the Oligocene has been a matter of debate. One way to infer presence/absence of glacial advance-retreat is by inferring eustatic sea level fluctuations from passive margins. However, recent advancements have shown that eustacy, while applicable in theory, cannot be applied in reality. These advancements involve the necessity to include the effects of gravitational attraction, crustal deformation and true polar wander in reconstructing sea level. All of these factors cause heterogeneity in the magnitude or even the sign of sea level change dependent on the position on earth and the position and evolution of gravitational masses on earth. Dinoflagellate cysts, which originate from surface dwelling dinoflagellates, are extremely sensitive to even small relative sea level changes (or better: proximity to shore, which is fundamentally different from sea level), and can be used to detect also high-frequency changes in relative sea level on continental margins. We here present dinoflagellate cyst assemblages of ODP Site 1172 and 1171, which bear a Maastrichtian to late Eocene section of ~continuous marginal marine sediments, to infer relative sea level changes in the region. The depositional setting was shallow in the Paleocene and early Eocene. The continuous record suggests that sedimentation kept up with basin subsidence. Dinoflagellate cyst assemblages, generally very sensitive to small sea level changes, show no high-frequency sea level fluctuations in the early Eocene, consistent with the absence of ice. However, despite the progressive deepening of the basin during the middle Eocene, dinocyst assemblages show increasingly high amplitude shifts reflecting relatively large third-order sea level fluctuations. The onset of continental-scale Antarctic glaciation in the Oligocene was such a major perturbation of the distribution of masses on earth, that, evidently from both modeling exercises and the records around Antarctica, sea level rose at the onset of glaciation.


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I will portray and discuss our dinocyst-inferred sea level reconstructions of the Paleogene Southern Ocean, in the light of the new insights in the forces acting upon sea level in reality. Morphometric Analysis on the Tribrachiatus Lineage: Quantifying Morphologic Variability During Speciation David Bord and Marie-Pierre Aubry Department of Earth and Planetary Sciences, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8066; [email protected] A morphometric analysis is in progress to characterize morphologic disparity during the evolution of the Early Eocene Tribrachiatus lineage. This lineage is one of the few indisputable lineages of coccolithophores. It consists of three successive (morphologic) species that have evolved through a rotation of two stacked equilateral triplets. The stem species, T. bramlettei, is a radially symmetrical, hexaradiate form; it evolved into an asymmetric form (T. contortus), which itself evolved into a triradiate form (T. orthostylus). The lineage is remarkably well expressed at North Atlantic DSDP Site 550, where it occurs over an 8.8 m interval (from the upper range of T. bramlettei through the range of T. contortus, up to the lower range of T. orthostylus). The transition from T. bramlettei to T. contortus is now well documented at this site, where it occurs over a thin stratigraphic interval (0.5 m) representing a few thousand years. It is best described as punctuated anagenesis, being similar to the speciation pattern described in G. tumida lineage by Malmgren et al. (1983). An eigenshape outline analysis has been conducted to complement the traditional approach in which the angles between the arms of the triplets were measured. Eigenshape analysis is a technique widely used for shape description in different scientific fields. It allows for the description, representation, and analysis of shape by reducing the acquired measurements to a minimum number of dimensions. This allows us to analyze the relationship of shapes in our samples. The morphologic pattern observed during the first speciation, from T. bramlettei to T. contortus, illustrates increasing morphologic variability during the transition, with morphotypes (“Mi”) exhibiting characters (such as the length of the arms and the angles between them) that are clearly intermediate between those of T. bramlettei and T. contortus. Within 0.5 m, the typical morphospecies T. contortus is established. However, of particular interest and unexpectedly, morphotypes Mi co-occur with T. contortus morphotypes throughout most of the range of T. contortus, albeit decreasing progressively in abundance. This suggests more than the straightforward replacement of an ancestral morphotype by a descendant morphotype. The analysis of the T. contortus —T. orthostylus transition will help shed light on the significance of the pattern described here. Benthic Foraminifera from the White Sea, Russia and their Implications for High Resolution Sea-Level Studies Martine Boswell1, Ben Horton2, Steve Culver3, Andrew Kemp4, Daria Nikitina5, Jessica Pilarczyk6, and Chris Vane7

1 University of Pennsylvania Department of Earth and Environmental Science ([email protected]) 2 University of Pennsylvania Department of Earth and Environmental Science 3 East Carolina University Department of Geological Sciences 4 Yale School of Forestry & Environmental Studies 5 West Chester University Department of Geology and Astronomy 6 University of Pennsylvania Department of Earth and Environmental Science 7 British Geological Survey

Benthic Foraminifera preserved in salt-marsh sediments can be used to produce high-resolution records of past relative sea-level change. Here we describe, for the first time, the distributions of foraminifera from the White Sea, Russia. We defined elevation-dependent ecological zones in three salt marshes along the Letnii shore using cluster analysis and detrended correspondence analysis. Several principal ecological zones of salt-marsh foraminifera were identified that have distinctive spatial distributions reflecting salinity regimes. High salinity sites along the Letnii shore are associated with sub-tidal calcareous assemblages, low marsh sites are dominated by Miliamimmina fusca and high marsh environments defined by Haplophragmoides manilaensis and Trochammina inflata. Spatial variation of foraminiferal populations and the potential for ecological zones to migrate in response to changing inlet configuration and salinity, suggests that modern salt-marsh foraminifera from multiple physiographically distinct environments would be appropriate for reconstructing former sea levels from the White Sea.


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Building a High-Resolution Eocene Calcareous Nannofossil Biozonation Using Ranking and Scaling (RASC) Andrew R. Bowman, David K. Watkins Statoil-Gulf Services LLC, EXP-NA-GOM; 2103 CityWest Boulevard; Houston, TX 77042; [email protected] Department of Earth and Atmospheric Sciences; University of Nebraska; Lincoln, NE 68588 A statistically rigorous methodology has been applied to data from various deepwater sections in an effort to refine the resolution of the existing Eocene calcareous nannofossil biostratigraphic zonations. Calcareous nannofossil abundances from two Ocean Drilling Program sections (Sites 1051A and 1052A, Leg 171B; “Blake Nose”) and one deepwater Gulf of Mexico well (Keathley Canyon, Block 774, Unocal #1; “Ponza”) were combined with calcareous nannofossil biostratigraphic data from published work, and incorporated into this study. A detailed evaluation of over 150 Paleogene taxa was carried out, using species distribution charts to aid in the biostratigraphic analysis, yielding the identification of the traditional bioevents (i.e., species range tops and bases), as well as recognition of new subordinate bioevents (e.g., first downhole increases/last frequent occurrence). All documented bioevents were then analyzed using probabilistic ranking and scaling sequencing (RASC). The RASC method resulted in the most probable order, termed the “optimum sequence” for the Paleocene-Eocene calcareous nannofossil bioevents. The biostratigraphic reliability of all bioevents (traditional and new/non-traditional) are quantified, and the resulting biozonation/optimum sequence includes only the reliable biostratigraphic events. Results of this work provide statistical information regarding the biostratigraphic reliability and confidence assigned to the traditional and non-traditional bioevents, and the discovery of useful new subordinate bioevents, produce increased biostratigraphic resolution on a well to field to basin-wide scale. Evolution of the Calcareous Nannofossil Genus Biscutum in the Mid to Upper Cretaceous North American Mid-Latitudes

Bobbi Brace and David K. Watkins University of Nebraska – Lincoln [email protected] The calcareous nannofossil genus Biscutum is ubiquitous in mid to Upper Cretaceous pelagic sediments. Biscutum constans is an important paleoceanographic proxy for surface water fertility (e.g., Roth, 1981; Roth and Bowdler, 1981; Roth and Krumbach, 1986; Watkins, 1989; Erba, 1992) and Biscutum species are important components in several Upper Cretaceous nannofossil zonation schemes (Wise, 1983; Jakubowski, 1987, Pospichal and Wise, 1990; Watkins et al., 1996; Burnett and Whitham, 1999). Unfortunately, species concepts within Biscutum have inconsistently been applied and interpreted owing to a convoluted taxonomic history, thus limiting its utility. Most work on the evolution of Biscutum has been conducted on high latitude sections (Wise and Wind, 1977; Wind, 1979; Wise, 1983; Jakubowski, 1987; Pospichal and Wise, 1990; Huber and Watkins, 1992, Watkins et al., 1996, Thibault, 2010) or Lower Cretaceous or Jurassic sediments (Grün and Allemann, 1975; Grün and Zweili, 1980; Bown, 1987; de Kaenel and Bergen, 1993; Mattioli et al., 2004). As such, Biscutum evolution in mid-latitudes of the mid to Late Cretaceous is poorly understood.

This study documents the evolution of Biscutum during the mid to Late Cretaceous in a mid-latitude composite section from North America. Samples from the Western Interior Basin (Washington County, KS; Smoky Hill type area, KS; and Sisseton, SD), the north Atlantic Ocean (ODP Leg 171B-1049A/1050C/1052E) and the Gulf of Mexico (DSDP Leg 10-95) were examined. Six new species of Biscutum are presented herein, in addition to a revised Biscutum constans species concept. A diversification interval is documented in the mid Cretaceous temperate latitudes during which five new species of Biscutum evolved in approximately six million years. Evidence from previous work (Huber and Watkins, 1992) indicates the occurrence of a second diversification interval in the Campanian high latitudes. These results suggest a distinct shift in the site of evolutionary activity within Biscutum, from the mid-latitudes in the mid Cretaceous to high latitudes in the Late Cretaceous. The appearance of common high latitude species of Biscutum in the mid-latitudes during the Campanian suggests that these occurrences are relatively brief migratory appearances from higher latitude settings. BOWN, P., 1987. Taxonomy, biostratigraphy, and evolution of late Triassic-early Jurassic calcareous nannofossils. Special Papers

in Palaeontology, 38:1-18. BURNETT, J. and WHITHAM, F., 1999. Upper Cretaceous. In: Bown, P., Ed., Calcareous Nannofossil Biostratigraphy, 132-199.

Cambridge: Kluwer Academic Publishing. DE KAENEL, E. and BERGEN, J., 1993. New Early and Middle Jurassic coccolith taxa and biostratigraphy from the eastern proto-

Atlantic (Morocco, Portugal and DSDP Site 547B). Eclogae Geologicae Helvetiae, 86:861-907. ERBA, E., 1992. Middle Cretaceous calcareous nannofossils from the western Pacific (Leg 129): evidence for paleoequatorial

crossings. In: Proceedings of the Ocean Drilling Program,Scientific Results, 129:189-201. GRÜN, W., and ALLEMANN, F., 1975. The lower Cretaceous of Caravaca (Spain): Berriasian calcareous nannoplankton of the

Miravetes section (Subbetic Zone, Prov. of Murcia). Eclogae Geologica Helvetica, 68:147-211.


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GRÜN, W. and ZWEILI, F., 1980. Das Kalkige Nannoplankton der Dogger-Malm-Grnze im Berner Jura bei Liesberg (Schweiz). Jahrbuch der Geologischen Bundesanstalt, 123:231-341.

HUBER, B. and WATKINS, D., 1992. Biogeography of Campanian-Maastrichtian calcareous plankton in the region of the Southern Ocean: Paleogeographic and paleoclimatic implications. Antarctic Research Series, 56:31-60.

JAKUBOWSKI, M., 1987. A proposed Lower Cretaceous calcareous nannofossil zonation scheme for the Moray Firth area of the North Sea. Abhandlungen der Geologischen Bundesanstalt, 39:99-119.

MATTIOLI, E., PITTET, B., YOUNG, J. and BOWN, P., 2004. Biometric analysis of Pliensbachian-Toarcian (Lower Jurassic) coccoliths of the family Biscutaceae: intra-and interspecific variability versus palaeoenvironmental influence. Marine Micropaleontology, 52:5-27.

POSPICHAL, J. and WISE JR, S., 1990. Maestrichtian calcareous nannofossil biostratigraphy of Maud Rise ODP Leg 113 Sites 689 and 690, Weddell Sea. In: Proceedings of the Ocean Drilling Program, Scientific Results, 113:465-487.

ROTH, P., 1981. Mid-Cretaceous calcareous nannoplankton from the central Pacific: Implications for paleoceanography. Initial Reports of the Deep Sea Drilling Project, 62:471–489.

ROTH, P. and BOWDLER, J., 1981. Middle Cretaceous calcareous nannoplankton biostratigraphy and oceanography of the Atlantic Ocean, S.E.P.M. Special Publications,32: 517–546.

ROTH, P. and KRUMBACH, K., 1986. Middle Cretaceous calcareous nannofossil biogeography and preservation in the Atlantic and Indian Oceans: implications for paleoceanography. Marine Micropaleontology, 10:235-266.

THIBAULT, N., 2010. Calcareous nannofossils from the boreal Upper Campanian-Maastrichtian chalk of Denmark. Journal of Nannoplankton Research, 31:39-56.

WATKINS, D., 1989. Nannoplankton productivity fluctuations and rhythmically-bedded pelagic carbonates of the Greenhorn Limestone (Upper Cretaceous). Palaeogeography, Palaeoclimatology, Palaeoecology, 74:75-86.

WATKINS, D., WISE JR, S., POPSICHAL, J. and CRUX, J.,1996. Upper Cretaceous calcareous nannofossil biostratigraphy and paleoceanography of the Southern Ocean. In: Moguilevsky, A. and Whatley, R., Eds., Microfossils and oceanic environments, University of Wales-Aberstyweth Press, 355-381.

WIND, F., 1979. Late Campanian and Maestrichtian calcareous nannoplankton biogeography and high-latitude biostratigraphy [Ph. D. dissert]. Florida State University, Tallahassee.

WISE JR, S., 1983. Mesozoic and Cenozoic calcareous nannofossils recovered by Deep Sea Drilling Project Leg 71 in the Falkland Plateau region, southwest Atlantic Ocean. Initial Reports of the Deep Sea Drilling Project, 71:481-550.

WISE JR, S. and WIND, F., 1977. Mesozoic and Cenozoic calcareous nannofossils recovered by DSDP Leg 36 drilling on the Falkland Plateau, SW Atlantic sector of the Southern Ocean. Initial Reports of the Deep Sea Drilling Project, 36:296-309.

Geochemical Discrepancy in two Globigerinoides ruber (white) Morphotypes During the Last Glacial Maximum: Implications for Paleo-Oceanographic Reconstruction? Elizabeth A. Brown, Pamela Hallock, and Benjamin P. Flower College of Marine Science, University of South Florida, St Petersburg, FL. [email protected] Globigerinoides ruber is a sub-tropical to tropical planktic foraminifera with two chromotypes (pink and white), dwelling in the upper mixed layer of the water column. Abundance and high turnover make G. ruber a common proxy for reconstructing both modern and past low-latitude oceanographic and climate conditions, through stable isotope and trace metal analysis. In addition to the two color variants, G. ruber (white) can be further subdivided into morphotypes. G. ruber sensu stricto (s.s.) has three increasingly large spherical chambers in the final whorl, each forming symmetrically over the previous suture, high-arched apertures, and a relatively thin CaCO3 test. G. ruber sensu lato (s.l.) has compressed subspherical chambers forming asymmetrically over the previous suture, with compressed apertures, and thick test walls (Figure 1). Variations in G. ruber morphology were noted as early as the 1970s. Recent studies in the South China Sea have, however, demonstrated that modern G. ruber s.s. and s.l. incorporate oxygen and carbon isotopes at a statistically significant offset. The compressed morphology and heavier δ18O composition of G. ruber s.l. indicated it calcifies at a deeper depth than G. ruber s.s. It is speculated that G. ruber s.s. occupies an ecological niche down to 30 m water depth, while G. ruber s.l. dominates from 30-50 m water depth. This offset in isotopic composition has since been corroborated through sediment trap and box core samples, while the calcification depth has been verified from sediment traps and live plankton tows. The G. ruber s.s. morphotype further exhibits higher trace metal (Mg/Ca) ratios than the G. ruber s.l. morphotype, suggesting modern G. ruber s.l. calcifies at cooler temperatures (0.8° to 2°C) than G. ruber s.s. One report (Wang 2000) hypothesized that the difference in δ18O diminished to near 0‰ during the Last Glacial Maximum (LGM) as a result of greater mixing in the upper water column due to intensified monsoon activity. Here we present new stable isotope and trace element (δ18O and Mg/Ca) data from fossil G. ruber (white) morphotypes in the Gulf of Mexico, which was the primary drainage basin for the Laurentide Ice Sheet in the early stages of the last deglacial period (23 to 19 ka), and well removed from effects of the monsoons of the Western Pacific. We compare our results with previously reported mixed G. ruber (s.s.+ s.l.) data from the same core, processed in the same analytical laboratory. Analyses were conducted on Orca Basin core MD02-2550 (26˚56.78’ N, 91˚20.74’ W; 2248 m water depth). LGM samples exhibit a mean difference between G. ruber s.l. and G. ruber s.s. of


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2 1

3 4

Figure 1. Specimens of two morphotype variations of Globigerinoides ruber (white) from box core top sediment samples, Orca Basin, Gulf of Mexico. 1-2: G. ruber s.s. 3-4: G. ruber s.l.

1.17 ± 0.6‰ for raw δ18O, and a mean difference in Mg/Ca of 0.79 ± 0.22 mmol/mol, corresponding to ~2.6°C. When comparing individual pairs of samples, G. ruber s.s. specimens exhibit a range of recorded temperature 1-4°C warmer than G. ruber s.l. during the LGM. When considered together, the mixed MD02-2550 record appears weighted toward a colder mean temperature, suggesting G. ruber s.l. was the dominant species in Orca Basin during the LGM. Geochemical differences between G. ruber (white) morphotypes may therefore have important implications for paleoceanographic reconstructions.

New Documentation on the Distribution Range of the Genus Catinaster and on its Evolutionary Relationships. Marina Ciummelli1 and Isabella Raffi1

1Dipartimento di Ingegneria e Geotecnologie (Ingeo) – CeRSGeo, Università “G. d’Annunzio” di Chieti-Pescara, Via dei Vestini 31, 66013 Chieti Scalo - Italy, Phone: +3908713556192, E-mail: [email protected] The genus Catinaster comprises small (5 to 10 µm) nannoliths, characterized by a basket-like shape, and is taxonomically related to the genus Discoaster, both belonging to the family Discoasteraceae (Tan, 1927). The species Catinaster coalitus is a well known marker used in the upper Miocene calcareous nannofossil biostratigraphy, that evolved from Discoaster, through the transitional species Discoaster micros (= D. transitus) (Peleo-Alampay et al., 1998; Raffi et al., 1998) around 10.8 Ma, and was closely followed by Catinaster calyculus at 10.7 Ma. Another species, Catinaster mexicanus has been sporadically recorded later, in upper Miocene (Bukry, 1973,1981; Ellis et al., 1972) and lower Pliocene sediments (Müller, 1974). This occurrence lacks of any evidence of an evolutionary relationship with the rest of the catinasters, and suggested an independent origin of C. mexicanus from Discoaster (Peleo-Alampay et al., 1998). Moreover, the mid-Pliocene occurrence of C. mexicanus is considered an “artifact” of preservation, being the specimens of C. mexicanus very similar, therefore ascribable, to the knobbed centre of Discoaster altus (= D. tristellifer) (Pujos, 1985). In the biostratigraphic study of sediment cores from the Eastern Equatorial Pacific, recovered at IODP Site U1338, besides the Miocene biostratigraphic markers C. coalitus and C. calyculus, C. mexicanus was recorded in discrete intervals in the upper Miocene and lower Pliocene sections, consistently with previous observations. The upper Miocene occurrence corresponds to a short time interval around 8 Ma and is concomitant with the appearance of Discoaster berggrenii (Figure 1). In the lower Pliocene, from 4 to ~3.6 Ma, C. mexicanus is commonly recorded, shows a continuous distribution and a relevant abundance turnover with D. altus, that sharply decreases in abundance when C. mexicanus increases (Figure 1). The C. mexicanus specimens observed in the upper Miocene are identical to those occurring in the Pliocene, and this suggests that a preservational effect for origination of the “Pliocene” C. mexicanus is unlikely, even though its concomitant occurrence with D. altus. It is noteworthy that the “upper Miocene” C. mexicanus is somehow associated with D. berggrenii, that is characterized by a stellate central


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area as the Pliocene species D. altus. The “Miocene” occurrence of C. mexicanus has been observed also at ODP Site 845 (Eastern tropical Pacific: Peleo-Alampay et al., 1998; this study) with the same abundance pattern as at Site U1338, and at ODP Site 926 (Equatorial Atlantic) with a rare but stratigraphically consistent presence. “Pliocene” specimens of C. mexicanus have been observed at ODP Site 926, as rare and scattered as in the upper Miocene. Our results evidence a peculiar distribution pattern of the species within the lineage of genus Catinaster, and the absence of an evolutionary link between the earlier species C. coalitus and the later C. mexicanus. We prove the validity of C. mexicanus as a species of genus Catinaster, the reliability of its occurrence in the mid-Pliocene, and document an evolutionary link between C. mexicanus and D. altus (previously suggested by Perch-Nielsen, 1985). C. mexicanus shows a wider geographic distribution than suggested before (Peleo-Alampay et al., 1998) that extends from the Eastern Equatorial Pacific, Caribbean and Indian Ocean to the equatorial Atlantic. Moreover, C. mexicanus seems to have had an unsuccessful “attempt at evolution” in the late Miocene. Bukry, D., 1973. Coccolith stratigraphy, eastern equatorial Pacific, Leg 16, Deep Sea Drilling Project. In van Andel, T.H., Heath,

G.R., et al., Init. Repts. DSDP, 16. U.S. Govt. Printing Office, Washington, DC, pp. 653–711. doi:10.2973/dsdp.proc.16.126.1973

Bukry, D., 1981. Pacific coast coccolith stratigraphy between Point Conception and Cabo Corrientes, Deep Sea Drilling Project Leg 63. In Yeats, R.S., Haq, B.U., et al., Init. Repts., DSDP, 63: Washington, DC (U.S. Govt. Printing Office), 445–471. doi:10.2973/dsdp.proc.63.111.1981.

Ellis, C.H., Lohmann, W.H., Wray, J.L., 1972. Upper Cenozoic calcareous nannofossils from the Gulf of Mexico (Deep Sea Drilling Project, Leg 1, Site 3). Colo. Sch. Mines Q., 67, 1–103.

Müller, C., 1974. Calcareous nannoplankton, Leg 25 (western Indian Ocean). In Simpson, E.S.W., Schlich, R., et al., Init. Repts. DSDP, 25: Washington, DC (U.S. Govt. Printing Office), 579–633. doi:10.2973/dsdp.proc.25.126.1974

Peleo-Alampay A, Bukry D, Liu L, Young JR. 1998. Magnetobiostratigraphic calibration of datums from the Miocene calcareous nannofossil Catinaster and discussion of its evolution. Journal of Micropalaeontology.

Perch-Nielsen, K., 1985. Cenozoic calcareous nannofossils. In Bolli, H.M., Saunders, J.B., and Perch-Nielsen, K. (Eds.), Plankton Stratigraphy: Cambridge (Cambridge Univ. Press), 427–554.

Pujos, A., 1985. Cenozoic nannofossils, central equatorial Pacific, Deep Sea Drilling Project Leg 85. In Mayer, L., Theyer, F.,Thomas, E., et al., Init. Repts. DSDP, 85: Washington, DC (U.S. Govt. Printing Office), 581–607. doi:10.2973/dsdp.proc.85.114.1985

Raffi, I., Backman, J., and Rio, D., 1998. Evolutionary trends of calcareous nannofossils in the late Neogene. Mar. Micropaleontol., 35(1–2):17–41. doi:10.1016/S0377-8398(98)00014-0

Tan Sin Hok, 1927. Discoasteridae incertae sedis. Koninkl. Nederl. Akad. Wetenschap. Proc. Sect. Sci., 30:411–419.

Figure 1: abundance patterns of lower Pliocene (A) and upper Miocene (B) selected calcareous nannofossils taxa at Site U1338. Scale bar 5 µm.

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Diachroneity and Dissolution in the Maastrichtian of Shatsky Rise, NW Pacific Kendra R. Clark, Serena Dameron, and R. Mark Leckie Geosciences, University of Massachusetts - Amherst, 611 N. Pleasant Street, Amherst, MA [email protected] Shatsky Rise is an open ocean, deep-water Pacific site that was located in the subtropics during the latest Cretaceous, just beyond the belt of equatorial divergence as evidenced by the loss of chert layers above the Campanian. The biotic record recovered at Shatsky Rise (ODP Sites 1209, 1210, and 1211) from the late Campanian-Maastrichtian (76.5-65.5 Ma) is unusual when compared with most other sites beyond the paleo-tropical Pacific because of: 1) sudden, short- lived acme of inoceramid clams at the shallowest sites during the “mid-Maastrichtian Event” (MME) (Bralower et al., 2002; Frank et al., 2005; this study), and 2) dissolution of planktic forams in the uppermost Maastrichtian paralleled by a sharp decline in planktic foram and calcareous nannofossil diversity (Lees and Bown, 2005; Clark et al., manuscript in prep). A thorough taxonomic and biostratigraphic study of planktic foraminifera from well-preserved and diverse late Campanian-Maastrichtian (76.5-65.5 Ma) assemblages has revealed significant differences in species ranges compared to detailed studies from the western North Atlantic (Blake Nose) and eastern South Atlantic (Walvis Ridge) indicating that many first and last occurrences appear highly diachronous between ocean basins (Clark et al., manuscript in prep). Benthic foram populations at Shatsky were not stable; they changed abruptly between epifaunal and infaunal dominance leading up to and after the MME. Based on benthic δ18O isotopes, the inoceramid clams appeared in abundance at Shatsky Rise at ~69.6 Ma when deep/intermediate water temperatures turned cooler and when epifaunal benthics dominated 60-70% of the foram community. Inoceramids disappeared for good ~69.1 Ma when temperatures increased sharply based on a -1.5‰ shift in δ18O values and when benthic foram assemblages switched back to infaunal dominance. Deep-water cooling was reinitiated after 68 Ma. What was an unexpected observation at Shatsky Rise was a dissolution event beginning ~66.1 Ma and lasting to the Cretaceous/Paleogene boundary (65.5 Ma). This event is characterized by chalky, highly fragmented planktic forams, increased dissolution of all larger taxa, abundance of tiny planktic forams, greatly reduced P/B ratio, a sharp decrease in planktic species richness, a significant decrease in benthic foram accumulation rates (BFAR), and a -2‰ shift in benthic δ13C. The dissolution event is preceded by a transitional interval beginning ~66.7 Ma containing planktic assemblages with highly variable preservation, and with well-preserved benthic forams. The transition interval is characterized by a precipitous decline in species richness. Studies of calcareous nannofossils at Shatsky Rise (Holes 577A, 1209C and 1210B) do not report dissolution in the latest Maastrichtian, but a decrease in primary productivity is suggested by a decline of meso- and eutrophic species abundances in the latest Maastrichtian that coincides with a drop in nannofossil species richness in parallel with the planktic forams (Thibault and Gardin, 2010). Further support of dissolution comes from core photo observations: Maastrichtian sediment is composed of nearly pure white nannofossil ooze, however at ~66.4 Ma, there is a change in color to a light-dark brown seen at ODP Sites 1209-1211. Variable color changes occur several times leading up to the boundary, especially in the ~65.6 Ma range coincident with the second and largest phase of Deccan volcanism. Population counts (>63 µm) through the dissolution interval reveal assemblages of juvenile biserial, trochospiral, and planispiral taxa; there are no ‘blooms’ of triserial Guembelitria in the uppermost Maastrichtian at Site 1209. These assemblages of tiny planktics may have survived dissolution by way of fecal pellet transport to the seafloor where they are found mixed in an assemblage of well-preserved calcareous benthic foraminifera. The observed dissolution at Shatsky Rise is one possible or partial explanation for the high diachroneity of species ranges between Pacific and Atlantic sites. Alternatively, the observed diachroneity may reflect site-specific influences of ocean circulation and productivity conditions in the three regions compared in this study (subtropical gyre, western boundary current, and eastern boundary current). The cause of the dissolution is unknown. Was dissolution due to changes in deep-water circulation, resulting in the shoaling of the carbonate compensation depth (CCD)? What was the extent of this dissolution event? Or could it have been the result of a global acidification event associated with Deccan Traps volcanism? Evidence for global warming near the end of the Maastrichtian has been reported by many studies, including paleogeographic migrations of tropical nannofossil and planktic foraminiferal species. This warming has been linked to Deccan Traps volcanism by Osmium isotope data (Thibault and Gardin, 2010). However, dates of the Deccan Traps flows do not coincide with the biotic changes and isotopic shifts observed at Shatsky Rise leading us to conclude that the latest Maastrichtian dissolution event was likely caused by a change in the CCD level and/or ocean circulation.


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Bralower, T., I. Silva, and M. Malone (2002), New evidence for abrupt climate change in the Cretaceous and Paleogene: An Ocean Drilling Program expedition to Shatsky Rise, northwest Pacific, GSA Today, 12(11), 4–10.

Clark, K. R., R. M. Leckie, and S. N. Dameron (manuscript in prep.), Late Campanian-Maastrichtian planktic foraminiferal biostratigraphy, taxonomy, and isotope paleoecology of ODP Leg Sites 1209 and 1210, Shatsky Rise.

Frank, T. D., D. Thomas, R. Leckie, M. A. Arthur, P. Bown, K. Jones, and J. Lees (2005), The Maastrichtian record from Shatsky Rise (northwest Pacific): A tropical perspective on global ecological and oceanographic changes, Paleoceanography, 20(1), PA1008.

Lees, J. A., and P. R. Bown (2005), Upper Cretaceous calcareous nannofossil biostratigraphy, ODP Leg 198 (Shatsky Rise, Northwest Pacific Ocean), in Extreme Warmth in the Cretaceous and Paleogene: A Depth Transect on Shatsky Rise, Central Pacific, Sites 1207-1214, vol. 198, edited by T. J. Bralower, I. Premoli Silva, and M. J. Malone, Ocean Drilling Program.

Thibault, N., and S. Gardin (2010), The calcareous nannofossil response to the end-Cretaceous warm event in the Tropical Pacific, Palaeogeography, Palaeoclimatology, Palaeoecology, 291(3-4), 239–252.

Anagenetic Evolution and Speciation within the Camplyosphaera Eodela-Dela Clade: A Response to Early Eocene Warming Matthew J. Corbett and David K. Watkins Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Lincoln, NE, 68588-0340, USA, [email protected] Quantitative morphological analysis of the calcareous nannofossil genus Camplyosphaera from the low latitudes in the North Atlantic (ODP Leg 171B) provides new insight into the biostratigraphy and evolutionary response of calcareous nannofossils during the Paleocene-Eocene Thermal Maximum (PETM) and Early Eocene Climatic Optimum (EECO). Nine hundred specimens of the Camplyosphaera eodela-dela clade from thirty samples between sites 1050a and 1051a were measured for overall length (L) and width (W) of the coccolith as well as the width of the central area (C) and rim (R). These samples are tied to age models developed for each site (ODP Initial Reports; Mita 2001) as well as the record of δ18O (Zachos et al. 2001) covering nearly 15 Ma of the Late Paleocene to Early Eocene. The average size of Camplyosphaera began to increase just after the PETM from less than 7 µm and stabilized to between 8-9 µm in length in mid-CP11 at the peak of the EECO. Camplyosphaera differta (Bown 2010), a morphotype where the cross completely fills the central area, only occurs within this interval (CP9a). Several important nannofossil groups see significant mutations and evolutionary change across these major perturbations in the oceanic system (Discoaster, Toweius, Rhoboaster/Tribrachiatus, etc.). It is possible the increase in Camplyosphaera size and appearance of C. differta are a response to increasing sea-surface temperatures at the PETM through the Early Eocene, though many factors can control variation in placolith morphology (e.g. Giraud et al. 2006). Detailed analysis of the observed specimens shows that changes in size cannot be explained by intraspecific variation alone and supports the recognition of two taxa: Camplyosphaera dela (Bramlette & Sullivan 1961) Hay & Mohler 1967 and Camplyosphaera eodela (Bukry & Percival 1971). Previous work has suggested that C. eodela is a junior synonym of C. dela and that the species gradually increases in size through the Eocene (Bybell and Self-Trail 1995). While a plot of length vs. width does imply gradual isometric growth through time (r = 0.86), scatterplots, histograms, and PCA analysis show two populations separated by change in the relative width of the central area. These groupings correspond very well to the original type descriptions of the two species and their separation in time argues against simple allometric differences. The older C. eodela ranges between 5-10 µm in size, but has a relatively narrow central area much less than half the width of the coccolith (<3 µm). This form is extremely rare above the middle of CP11. The younger C. dela is generally larger (7-11 µm in size) but has a more open central area typically equal to or greater than half the total width (≥3 µm). The first C. dela has a lowest occurrence in CP9a but does not become common until CP10-11. This transition, to larger and more common C. dela and highest common occurrence of C. eodela, may serve as an additional biostratigraphic datum to subdivide CP11.


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Biostratigraphic Analysis of Mass Transport Deposits and Turbidites in the Lower Miocene of the Gulf of Mexico J. A. Crux, J. M. Casey and F. J. Peel, BHP Billiton Petroleum, 1360 Post Oak Boulevard, Houston, Texas 77056, USA. [email protected] Seismic data from the lower Miocene of the Gulf of Mexico Atwater Valley protraction area shows dramatic stratigraphic character changes. These are alternations of laterally continuous reflectors with less continuous more chaotic reflectors. The former are usually interpreted as turbidite deposits and the latter are considered to be Mass Transport Deposits (MTDs). The current study sets out to verify these interpretations using biostratigraphy and fossil abundance patterns. The analysis of fossil abundance patterns from three well sections through an interpreted MTD, that today sits on top of a salt cored high in approximately 6250 feet of water, is presented. The sediments are deposited on a condensed Oligocene carbonate that is present throughout the region. Initial sedimentation is of calcareous turbidities with benthic shelf foraminifera (Amphistegina lessoni.) and mixed Miocene and Oligocene planktonic foraminifera and nannofossils; these include Globorotalia kugleri, Triquetrorhabdulus carinatus and Sphenolithus disbelemnos. These turbidites are overlain by an interval tentatively identified from the seismic data as an MTD emplaced block or relict topography that survived the emplacement of the MTD. It is composed of turbidites and interbedded shales, the fossil content is relatively sparse with increasing numbers of reworked Cretaceous fossils upwards through the succession. Miocene and Oligocene fossils are concentrated in the sands and their silty laterally equivalent sections. The reworked Cretaceous fossils are interpreted to be derived from the shelf where they had been deposited by early Miocene rivers that eroded the Cretaceous outcrop. The mixing of Miocene and Oligocene fossils is interpreted as the result of turbidites scouring the upper and middle slope and entraining older fossils. The relict topography or MTD block(s) is overlain by an initial interval of turbidite deposition, again rich in mixed age fossils and shelf benthic foraminifera Amphistegina lessoni. Sphenolithus belemnos is present throughout this interval. A fourth interval of sediments also appears to fill topography around the older relict sediments/MTD block, this is dominated by reworked Cretaceous fossils with very little Oligocene and less Miocene species than the underlying interval. It is not known if this dominantly shale rich interval is further turbidites or MTDs. Local seismic data shows oblique reflectors separating these sediments from the relict topography/MTD block. The whole complex is overlain by an extensive sand rich turbidite fan that yields the nannofossil Sphenolithus belemnos. The interpretation presented here is not the only one possible, but it attempts to explain the complex fossil distribution patterns observed and the seismic reflection data in an integrated manner.


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Reconstructing Jurassic and Cretaceous Paleoenvironments in Armenia Based on Radiolaria and Foraminifera; Implications for the Geodynamic Evolution of the Tethyan Realm in the Lesser Caucasus T. Danelian1, A. Zambetakis-Lekkas2, G. Asatryan3, A. Grigoryan3 1 University Lille 1, Department of Earth Sciences, CNRS-UMR 8217 “Géosystèmes”, SN5, 59655 Villeneuve d’Ascq,

France; [email protected] 2 University of Athens – Department of Geology & Geoenvironments, Panepistimiopolis-Zografou, 15784 Athens,

Greece 3 Institute of Geological Sciences, National Academy of Sciences of Armenia, 24a Baghramian av., Yerevan, 375019,

Republic of Armenia Three main paleogeographic realms can be distinguished in Armenia during the Mesozoic: 1) the South-Armenian Block, a Gondwana-derived terrane; 2) the Tethyan oceanic realm, represented essentially by ophiolitic lavas and their sedimentary cover; 3) the Eurasian plate, which was an active margin for most of the Jurassic and Cretaceous. This is one of the key areas of the Alpine-Himalayan mountain belt, situated at the junction of suture zones between Turkey and Iran. However, lateral correlation of the various tectono-sedimentary and ophiolitic units is difficult, mainly because of the paucity of detailed age constraints. We here present micropaleontological results obtained from the sedimentary cover of the Sevan-Akera ophiolites in Armenia and the Upper Cretaceous carbonate platform sequence of the South-Armenian Block, prior to the obduction of ophiolites. Radiolarian biostratigraphic results from a large number of localities across the Sevan-Akera suture zone and from Vedi establish that radiolarian ooze accumulated on oceanic floor during (at least) the Bajocian to Cenomanian time interval. Lava flows and tuffites intercalated in the radiolarian chert sequences establish that both submarine and subaerial volcanic activity was taking place during most of this interval. A recently obtained radiolarian fauna from the Amassia ophiolite (NW Armenia) provides an important time constraint for the youngest submarine volcanic event of the Tethyan realm preserved in the Lesser Caucasus. It is characterised by the co-occurrence of Archaeodictyomitra montisserei, A. undata, Pseudodictyomitra pseudomacrocephala and P. tiara, an assemblage that points to a Cenomanian-Turonian age. Two latest Tithonian – late Valanginian radiolarian assemblages recovered from north and east of lake Sevan (Dzknaged and Dali outcrops, respectively) are of particular significance; they were extracted from radiolarian chert sequences that are intercalated with mafic rocks formed after episodes of submarine volcanic activity. Both radiolarite sequences contain rounded blocks of limestone (oolitic grainstone with fragments of crinoids); they provide evidence for shallow water platform carbonates in the neighbourhood, fragments of which slid into a bathymetrically complex oceanic sea floor. Both assemblages are characterized by the presence of Obesacapsula cetia and Dicerosaturnalis trizonalis. The assemblage from Dali appears to be more diverse, with over 30 species identified so far, amongst which Parapodocapsa amphiterptera is the most abundant. The rare presence of Vallupus japonicus at Dzknaged is of particular significance, as it suggests that these radiolarites accumulated in the tropical biogeographic realm of the “Vallupus territory”. In the area of Vedi (SE of Yerevan) an ophiolitic folded klippe sequence is thrusted on the South-Armenian Block, which was probably part of the Taurides-Anatolides micro-continent and detached from Gondwana during the Late Palaeozoic – Early Mesozoic time. The Vedi area is important in many ways, especially because it allows the detailed study of the obduction of ophiolites to the South-Armenian carbonate sequence; the latter is overlain stratigraphically by a flysch that ends with an olistostome containing a large variety of ophiolite-derived blocks. Microfacies observation of the last 50 m of the carbonate sequence suggests a back-reef inner platform depositional environment, with the presence of Cuneolina sp., Pseudocyclammina rugosa, Terquemella sp., Boueina sp., echinoderms and frequent clasts of Rudists. The Foraminiferan assemblage attributes a Cenomanian age. Foraminifera of the Qom Formation as Paleoenviromental Indicators in North of Central Iran Basin, North East Garmsar, Iran J. Daneshian* and L. Ramezani Dana** *Geology Department, kharazmi University, No. 43, Mofateh Ave., Tehran, Iran. [email protected] **Geology Department, Kharazmi University, No. 43, Mofateh Ave., Tehran, Iran. [email protected] Among investigations Oligo-Miocene deposits in Middle East, Iran is one of the region which has few or either no acceptable and accessible information for palaeontological surveys. It is clear that for reconstructing of Oligo-Miocene palaeogeography of middle east, paleontological data, specially microfossils are essential. So in this research, Oligo-Miocene deposits from Central Iran which called the Qom Formation, based on Benthonic foraminifera due to


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paleoenviromental investigations, has been studied. Previous studies of the Qom Formation display that foraminifera are one of the most important and abundant fauna. This rock unit with considerable widespread occurs in variety of bio and litho facies, and it is useful for reconstructing of Oligo-Miocene palaeogeography in Central Iran. Thickness of the Qom Formation in the studied section is sizable and mainly consists of limestone. According to foraminifera, these deposits are early Miocene (Aquitanian –Burdigalian) in age. Semi-quantitative studyie in this section indicate that main and most contents of foraminifera belong to Miliolidae and among them Quinqueloculina, Triloculina and Spiroloculina are most abundant. Based on variety and abundance of foraminifera species and genera in the studied section, three assemblages have been identified which from base, assemblage 1, 2 and bottom of assemblage 3 is related to Aquitanian and rest of that to Burdigalian . There is reasonable coordination between diversity and abundance of foraminifera and with increasing number of them in assemblages, variety increase. Appearance of some foraminifera like Ammonia beccari and Rotalia viennotti in first assemblage and Triloculina trigonula with Quinqueloculina sp. in the second one display shallow and warm water (inner shelf) . In the third assemblage Quinqueloculina sp., Spiroloculina sp. and Triloculina trigonula are most abundant and these associations almost show the same condition in the environment. This situation can be consequence of depth undulation of the basin which related to unstable sea level changes. Multiple "Filament" Events in the Cenomanian-Turonian Eagle Ford of South Texas: Global Correlation and Possible Causal Factors Richard A. Denne1, Achim Herrmann2, Russell E. Hinote3, and Joan M. Spaw1 [email protected] 1 Marathon Oil, 5555 San Felipe, Houston, TX 77056 2 Louisiana State University, E235 Howe-Russell, Baton Rouge, LA 70803 3 Ellington and Associates, 1414 Lumpkin Rd, Houston, TX 77043 The Cenomanian-Turonian boundary "Filament Event" is a zone of high concentration of thin (<5 microns thick) "filaments" identified in thin section that are thought to represent the planktonic phase of bivalve larvae. This event has been identified in platform sediments from the Tethyan Seaway of North Africa, the Western Interior Seaway of the US, and England (Negra et al., 2011). The base of the event has been found either just above or below the Cenomanian-Turonian boundary, depending on how the boundary is defined, leading some authors to use it as a readily identifiable marker for the boundary (e.g. Caron et al., 2006). Due to the event's occurrence within OAE2, most authors have suggested that it was caused by the suffocation of planktonic larva as they settled from oxygenated surface waters to anoxic bottom waters (Robaszynski et al., 2010). Examination of thin sections from cores taken in Atascosa and Karnes County, Texas, verified the presence of abundant "filaments" near the Cenomanian-Turonian boundary within the Eagle Ford Formation. In addition, this study identified a total of four zones of high "filament" abundance, two within the Cenomanian Lower Eagle Ford (Rotalipora cushmani Zone) and two within the Turonian Upper Eagle Ford (Whiteinella archaeocretacea and Helvetoglobotruncana helvetica Zones), with the basal Turonian zone correlating to the published "Filament Event". It is not known if the Cenomanian zones are restricted to the Eagle Ford or if they were not identified by previous researchers due to their focus on the boundary interval. Within the area of investigation, the bottom waters during the time of deposition of the Lower Eagle Ford were nearly anoxic, based on the relatively high concentrations of vanadium, molybdenum, and organic matter, which is supported by the rarity of in situ benthic organisms, including foraminifera and ostracods, and the Chondrites ichnofacies. The Upper Eagle Ford, however, is interpreted to have had oxygenated bottom waters based on the presence of benthic organisms, and lower concentrations of vanadium, molybdenum, and organic matter. As the upper two "filament" zones are found within the oxygenated Upper Eagle Ford, anoxia is unlikely to be the primary causal factor. Recent research has identified oceanic acidification as the most probable cause for bivalve larva declines in modern estuaries (Miller et al., 2009), suggesting that acidification may be responsible for the Cenomanian-Turonian die-offs. Further research is needed to determine if this is a valid supposition, and if the "filament" zones are periods of higher larva production or strengthened acidification. Caron, M., Dall’Agnolo, S., Accarie, H., Barrera, E., Kauffman, E. G., Amédro, F., and Robaszynski, F., 2006. High-resolution

stratigraphy of the Cenomanian-Turonian boundary interval at Pueblo (USA) and wadi Bahloul (Tunisia): stable isotope and bio-events correlation. Geobios, v. 39, p. 171-200.

Miller, A. W., Reynolds, A. C., Sobrino, C., and Riedel, G. F., 2009. Shellfish face uncertain future in High CO2 world: influence of acidification on oyster larvae calcification and growth in estuaries. PLoS ONE, v. 4, e5661.

Negra, M. H., Zagrarni, M. F., Hanini, A., and Strasser, A., 2011. The filament event near the Cenomanian-Turonian boundary in Tunisia: filament origin and environmental signification. Bulletin de la Société Géologique de France, v. 182, p. 507-519.

Robaszynski, F., Zagrarni, M. F., Caron, M., and Amédro, F., 2010. The global bio-events at the Cenomanian-Turonian transition in the reduced Bahloul Formation of Bou Ghanem (central Tunisia). Cretaceous Research, v. 31, p. 1-15.


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Thin section photomicrograph (XPL with quartz plate) of “filaments” from the Cenomanian of the Lower Eagle Ford. Thin Section Foraminiferal Biostratigraphy of the Cenomanian-Turonian Eagle Ford Formation, South Texas Richard A. Denne1, Russell E. Hinote2, Nancy Engelhardt-Moore2, and Joan M. Spaw1 [email protected] 1 Marathon Oil, 5555 San Felipe, Houston, TX 77056 2 Ellington and Associates, 1414 Lumpkin Rd, Houston, TX 77043 Samples from cores taken in Atascosa and Karnes County, Texas, were examined for foraminifera in the Cenomanian-Turonian Eagle Ford and adjacent formations. In three cores the study included thin sections with corresponding washed residue samples. The foraminiferal assemblage was found to be dominated by species of the small planktonic genera Heterohelix and Hedbergella. Layers of larger planktonic foraminifera that have been winnowed or transported by bottom currents are composed primarily of globose Whiteinella spp. and larger specimens of Hedbergella spp., with rare occurrences of thick, keeled forms, plus rare to common inoceramid fragments and fish bones. Benthic foraminifera are rare to absent in the Lower Eagle Ford of the study area, but rare to common in the Upper Eagle Ford. Thirteen potentially useful horizons were identified in the cores (in ascending order): (1) tops of Favusella washitensis and Rotalipora appenninica, (2) top of R. brotzeni (3) base of R. cushmani, (4) base of Heterohelix reussi / globulosa, (5) base of oldest "filament" event (acme of bivalve larva), (6) tops of R. cushmani and R. greenhornensis, (7) base of abundant H. reussi/globulosa, (8) base of global "filament" event, (9) base of Helvetoglobotruncana helvetica with re-entrance of Dicarinella spp., (10) top of H. helvetica, (11) base of Marginotruncana coronata with top of Guembelitria cenomana, (12) top of Anomalina "W", and (13) top of D. hagni. The high abundance of small Heterohelix specimens made it difficult to identify the Heterohelix "shift" noted in other areas near the Cenomanian-Turonian boundary (Leckie, 1985). A morphological shift from slender forms (H. moremani) below to more globular forms above (H. reussi / globulosa) was seen at the boundary, along with an uphole increase of G. cenomana, which probably correlates to the Heterohelix "shift". The re-entrance of benthic foraminifera near horizon 6 is locally useful, but is assumed to be time-transgressive over long distances. Although foraminifera were generally highly abundant in the thin sections, they were often under-represented or absent in washed residue samples due to the very small size of many Heterohelix specimens, and poor recovery in diagenetic limestones and thermally mature marls. This is particularly noticeable when direct comparisons were made between the abundances found in thin-sections and washed residues from the same sample. Analysis of thin


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sections also allowed for the identification of microfossils that are difficult to recover (e.g. radiolaria, calcispheres, and "filaments"), and made it possible to place the fossils within a sedimentological context. Disadvantages to relying on thin sections are the inability to identify some specimens beyond the genus level and the smaller sample size. Leckie, R.M., 1985. Foraminifera of the Cenomanian-Turonian boundary interval, Greenhorn Formation, Rock Canyon Anticline,

Pueblo Colorado. in: Pratt, L.M., Kauffman, E.G., Zelt, F.B. (eds.), Fine-grained Deposits and Biofacies of the Cretaceous Western Interior Seaway: Evidence of Cyclic Sedimentary Processes. SEPM, 2nd Annual Meeting, Golden, CO, Field Trip Guidebook 4, p. 139–149.

Thin section photomicrograph (XPL with quartz plate) of typical winnowed Whiteinella / Hedbergella layers in the Lower Eagle Ford.

Thin section photomicrograph (XPL with quartz plate) of abundant Heterohelix moremani and Hedbergella spp. from the Lower Eagle Ford.

The Role of Benthic Foraminiferal Assemblages in the Postglacial Coastal Evolution: A Regional Model from the Tyrrhenian Basin (Mediterranean) Letizia Di Bella*, Virgilio Frezza, Mauro Alivernini, and Antonio Faugno Earth Science Department Of University of Rome “Sapienza”. [email protected] The landscape evolution of the late Quaternary Tyrrhenian coast during the Holocene was controlled by the rates of postglacial sea-level rise and fluvial input. In this study the microfaunal data coming from some significant Italian coastal sites were considered in order to elaborate an evolutionary model valid at regional level, by mean of benthic foraminiferal assemblages. The coastal depositional system is characterized by a lowstand phase, which developed during the eustatic sea-level fall between about 120 and 30-26 kyr BP. During the late lowstand phase, which is characterized by stillstand and slow eustatic sea-level rise, lagoon and marsh associations occurred. These paralic environments are very sensitive to coastline variations, and provide one of the most sensitive tools for studying sea level change. One of their main characteristics is the degree of marine influence that depends on climatic conditions and on the coastline morphology and evolution. Foraminiferal assemblages represent one of the most important microfaunistic component of the paralic environments for their high adaptability also in euryhaline conditions. Salinity seems to be the most significant factor controlling the foraminiferal distribution in these environment although other parameters like organic and oxygen content could have a great influence on the frequencies of the taxa and on the assemblage composition. Two assemblages were recognized distinguished on the base of different confined conditions. The first one (Ammonia parkinsoniana, Ammonia tepida, Haynesina depressula and Haynesina germanica assemblage) is characterized by very low a-Fisher index (mainly < 5) and it can be related to very strong restricted conditions that can be found in environments as the inner lagoon. The second assemblage (Ammonia parkinsoniana, Ammonia tepida, Aubignyna perlucida and Elphidium poeyanum assemblage) shows a minor oligotipic degree (a-Fisher index between 5 and 10) and indicates brackish-water conditions, but with a lower level of environmental stress (probably an outer lagoon with periodic connections with the sea. During the transgressive phase coastal-shelf sedimentation took place and the littoral area was interested by a barrier-lagoon system, consisting of small brackish lagoon delimited towards the sea by sandy bars. The paralic assemblages were quickly replaced by normal marine shallow waters associations testifying the sea level rise. This conditions are indicated by Ammonia spp. and Elphidium spp. assemblage typical of infralittoral zone with sandy


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bottoms (a-Fisher index > 10). Locally this infralittoral environment was colonized by Posidonia oceanica meadows as suggested by high frequencies of epiphytic taxa (miliolids, a-Fisher index > 10). During the subsequent highstand phase and sea-level stabilization the foraminiferal assemblages reflect the current microfaunal distribution and the establishment of modern water circulation pattern (Globocassidulina subglobosa, Melonis pompilioides and Reussella spinulosa assemblage with Alpha Fisher index > 10). After the sea-level stabilization, locally the coastal progradation and flood events lead to freshwater marsh episodes followed by backshore environments. On the whole, five main characteristic benthic foraminiferal assemblages are recognized in the Holocene cores: two indicate lagoonal or, in general, confined environments, two are related to marine infralittoral zone (0-50 mwd) and, finally, one is characteristic of the upper circalittoral zone (50-100 mwd). Palynology and Paleoenvironment of Paleocene-Eocene Wilcox Group Sediments in Bastrop, Texas Regina L. Dickey Department of Geology and Geophysics, Texas A&M University, MS 3115 College Station, Texas 77843-3225 [email protected] The Wilcox Group is an intensely studied group of sediments deposited primarily during the Laramide orogeny in the western United States and is important in paleoclimatological and paleoenvironmental studies, as it pertains to the Paleocene-Eocene Thermal Maximum (PETM). This particular stratigraphic section in the northwestern part of the Gulf of Mexico region has limited documentation of the changes in microbiota, despite the high level of interest in the interval. The section is thick but fossil content is sparse, except for fossils of plant origin. The majority of fossil remains present are derived from land plants, with pollen and spores being widely distributed. The organic acids produced by the decay of plant tissue have resulted in the diagenetic loss of nearly all carbonate remains. Therefore, palynology provides the best means of documenting the record of environmental change for these deposits. Palynological sampling within a 20 m (66 ft.) section of Calvert Bluff and Carrizo Formation strata and a nearby 10 m (33 ft.) section of upper Calvert Bluff and lower Carrizo contain a rich assemblage of well-preserved palynomorphs and occasional dinoflagellates (Figs. 2 and 3) in outcrops containing a major sequence boundary. Calvert Bluff strata consist of shoaling-upwards, fine-grained shallow marine deposits; the sequence boundary is marked by a paleosol and incised channel fill; the Carrizo is a transgressive marine sand deposit (Fig. 1). The palynomorphs recovered from the Calvert Bluff Formation indicate environments ranged from warm adapted swamps with cypress, mosses and palms to upland deciduous forests with birch, alders and black gum. These were all transported and deposited in an offshore ocean bottom location. Ferns are prevalent throughout the section, with spikes evident within sampling. Ferns are often interpreted to be a common disturbance vegetation in Late Cretaceous through Paleogene wetlands (Collinson et al., 2003). Conifers of both temperate and tropical affinity are also present. The palynomorphs and dinoflagellates present in these sections are essential in reconstructing paleoenvironmental conditions present at the time of deposition.


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Figure 1. Location of study area and stratigraphic section of the upper Calvert Bluff Fm. and Carrizo Fm., Red Bluff section, Bastrop County, Texas.

Figure 2. Examples of Eocene palynomorphs of the Calvert Bluff Formation in the Red Bluff section, Bastrop County,Texas. (A) Platycaryapollenites. (B) Bagelopollis verrucatus. (C) Sonneratiaceae. (D) Spinaeapollis spinosus. (E) Symplocoipollenites.

Figure 3. Cordosphaeridium sp. (top) and Apectodinium homomorphum (bottom).

Thecamoebians and Tintinnids: Evidence of Long-Term Industrial Activity in Sluice Pond, MA M. Drljepan1, F.M.G. McCarthy1, and J.B. Hubeny2 1Brock University, St. Catharines, Ontario, [email protected] 2Salem State University, Salem, MA Sluice Pond is a small (18 ha) and deep (zmax 19.8 m) lake in Lynn, Massachusetts whose meromoxis results in excellent preservation2. Lynn was settled in AD 1629; a leather tannery and shoe industry began in 16351. Sluice Pond was impacted by effluent from these industries, by the construction of a dam in the mid 17th C3 and by continued population expansion, allowing Lynn to achieve city status by the early 19th C. Pollen assemblages confirm that a complete late-glacial to recent record is preserved in the deep basin2 and preliminary observations suggest that protozoans and algae responded to climate change and to anthropogenic disturbance2. The fossil record of the thecamoebians (testate amoebae) and tintinnids was used to determine the effects of long-term settlement and industrial activity. Four cores were taken from Sluice Pond: two Rawley-Dahl cores (74 and 111cm- long) and two piston cores- SP07 and SP09 (200cm and 457.7cm- long, respectively). In cores SP07 and SP09, the presence of Codonella cratera, a tintiniid recording anoxic, bottom waters increases in the upper core (to 50% in core SP07 and 89% in core SP09), whereas in the Rawley-Dahl cores, C.cratera are rare (<2%). The occurrence of Cucurbitella tricuspis- a thecamoebian present in eutrophic conditions- is 68% of total thecamoebians at 20 cm in the SP07 core and 74% of total thecamoebians at 10cm in core SP09. Difflugia protaeiformis reaches its greatest abundance (5.6%) at 70cm in core SP07 and at 70cm in SP09 (6.8% of

the total population). The presence of C.tricuspis and D. protaeiformis in the upper sections of the cores indicates high phosphorus loading6, and the planktonic phase of C. tricuspis allows it to escape seasonal anoxia. Phosphorus is the main limiting nutrient associated with cultural eutrophication. The low species diversity (SDI = 0.82-1.50) indicates ecological stress accompanying the increase in anthropogenic activity surrounding Sluice Pond. At approximately 100cm SP07 and 200cm in SP09, the total number of specimens/mL (i.e. concentration) increases


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markedly and abruptly during pollen zone 3b5 (~5.4- 3.0 ka) from 2.8 total specimens/mL at 100cm to 107.6 total specimens/mL at 90cm in core SP07 and from 25.2 total specimens/mL at 221cm to 138.5 total specimens/mL at 191cm in core SP09.

The Rawley-Dahl cores contain low abundances of ubiquitous thecamoebian taxa, Centropyxis aculeata and Difflugia oblonga. This is probably due to abundant woody tissue in the sediments, because the low availability of silica inhibits the presence of coarsely agglutinated difflugiids whereas organic-walled centropyxids are common. These sediments also contain exceptionally preserved dinoflagellate thecae and relatively abundant cysts (>5000/ mL) reflecting the anoxic bottom waters. 1City of Lynn. (2012) A Brief History of Lynn. http://www.ci.lynn.ma.us/aboutlynn_history.shtml 2Hubeny, J.B., McCarthy, F.M.G., Lewis, J., Cantwell, M., Morissette, C., Krueger, A.M., Zanatta, R., Drljepan, M., Ritch, N.M., and

Crispo, M.L. (In prep) Holocene stratigraphy, environmental history, and regional hydroclimate significance of Sluice Pond, northeastern, MA.

3Lewis, A., and Newhall, J.R. (1865) History of Lynn, Essex County, Massachusetts, Boston, MA, John L. Shorey Publisher. 4McAndrews, J.H. (1994) Pollen diagrams for southern Ontario applied to archeology. In MacDonald R (ed.) Great Lakes

Archeology and Paleoecology, Exploring Interdisciplinary Initiatives for the Nineties. Quaternary Sciences Institute. University of Waterloo. Pages: 179-196

5Patterson, R.T., Roe, H.M., Swindles, G.T. (2012) Development of an Arcellacea (testate lobose amoebae) based transfer function for sedimentary Phosphorus in lakes. Palaeogeography, Palaeoclimatology, Palaeoecology. 348-349: 32-44.

Feeding Habits of Deep Water Benthic Foraminifera: An Experiment with Propagules Christopher James Duffield* and Elisabeth Alve Department of Geosciences, University Of Oslo. *Corresponding author: [email protected] An experiment was designed to investigate how benthic foraminifera respond to changes in food availability and sediment depth. Using a number of treatments and controls, the experiment specifically aimed to investigate the following: 1) Response of juvenile foraminifera to sediment conditions where there is no input of organic matter 2) The effects of increasing the sediment depth, in both fed and unfed conditions 3) If preference of a particular food source exists. 4) How seasonal changes in the plankton community may affect the foraminifera.

The experiment followed a method modified from Alve & Goldstein (2003). Before the start of the experiment, sediment collected from the Oslofjord at 355 m water depth was passed through a 53 µm sieve. In the experiment the fine fraction was used. The experiment was carried out over a period of six weeks, with treatment taking place once a week. Each treatment or control had four replicate microcosms. During the six weeks the microcosms were kept sealed in the dark in an environmental test chamber at ambient temperature (7°C).


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Monospecific algal cultures of the green algae Dunaliella sp., the haptophyte Emiliania huxleyi and the diatoms Chaetoceros sp. and Navicula sp. were offered as food sources. In addition, net haul samples from the surface water at the 355 m site were used as food sources, as well as a 200 µm net haul dominated by crustacean zooplankton. The amount added for each of these food treatments was equal in terms of carbon content. No living algae or zooplankton were added in order to control the amount of food available and prevent the food organisms from altering the environment. At the end of the experiment the sediment was washed through a 63 µm sieve. Any foraminifera being caught on the sieve therefore must have grown during the experiment. The analysis of the results reasons that in order to grow during the experiment individuals must have found the conditions favourable, or at least tolerable. At the experiment start only a few individuals (<16) were present. Six weeks later the abundance had significantly increased in all treatments and unfed controls. Although there was a significant change in abundance of certain species, there was no major change in species composition between treatments or controls. Some treatments appeared to have a negative effect, with abundances below those of the unfed controls. The results have significance in the understanding of the genesis of foraminifera which has implications in not only the understanding of the ecology of modern day foraminifera but also the interpretation of the fossil record. Alve, E. & Goldstein, S. T. (2003) Propagule transport as a key method of dispersal in benthic foraminifera (Protista). Limnology and

Oceanography, 48, 2163-2170. Foraminifera as Ecological Indicators at Potengi Estuary and Adjacent Continental Shelf (Natal, RN) Patrícia P. B. Eichler, Théo de Tarzo, and Helenice Vital Programa de Pós Graduação em Geofísica e Geodinâmica (PPGG), Laboratório de Geologia e Geofísica Marinha e Monitoramento Ambiental, Centro de Ciências Exatas e da Terra da Universidade Federal do Rio Grande do Norte (GGEMMA, CCET, UFRN), Campus Universitário, Lagoa Nova, 59078-970 Natal, RN, Brazil. Caixa Postal: 1596. [email protected] We focus on the response of the spatial distribution of benthic foraminifera species to physical, geological and chemical properties in the paralic and marine environment of Potengi River to assess the degree of pollution and to recognize the presence of areas under effluent from shrimp and / or domestic sewage. The estuary of the Potengi River is located between 05º52'00" and 05º41'57"S and the meridians 35º19'16" and 35º08'24"W, including the city of Natal, Capital of Rio Grande do Norte State. Sampling was done within the urban area of Natal, and in the north and south of its adjacent platform. We have collected a total of 18 bottom sediments samples with Van Veen. After collection, the uppermost layer of the sediment (about 1 cm) was removed and stored in a mixture of 30% alcohol and buffered (Na2B4O710H2O) Rose Bengal stain (1g of rose Bengal in 1l of distilled water). After staining, a 10 cm3 volume of sediment was washed through a sieve of 0.063mm mesh and dried. Species identifications and estimate counting were done under an optical microscope. The quantitative analyses of the data were based on counts of living (stained) and dead specimens. Absolute and relative abundances of Foraminifera species were recorded for each sediment sample. Simpson dominance and Shannon–Wiener diversity were determined by PRIMER. A standardized environmental data matrix (depth, temperature, bottom and surface salinities, and percentages of sand, silt, clay, organic carbon and sulfur) was subjected to PCA to identify environmental trends. Relative abundance data were computed for foraminiferal species that contribute 10% or more to the assemblage in more than one sample, and subjected to Q-mode cluster analysis. Bray–Curtis distance coefficient was used to measure differences between samples, and Ward’s linkage method was used to group samples into a hierarchical dendrogram. In the PCA analysis (Figure 1) Group P1 is composed by stations 14 and 17 with similar temperature, CaCO3 content and very coarse sand. The group P2 is formed by stations 2, 5, 11, 12 and 18, which have similar high percentages of gravel and coarse sand fractions. The group P3 contains stations 1, 13, 15 and 16, and it is characterized by high percentages of fine sand, very fine sand, silt and clay. Group P4 consists of stations 3, 4, 6, 7, 8, 9 and 10 with higher salinity, conductivity, density, and sediment with medium sand fraction.


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Figure 1: Groups of stations according to the values of PC1 and PC2.

Cluster analysis shows that group C1 consists of stations 7 and 8 where Ammonia tepida and Quinqueloculina lamarckiana dominate followed by Textularia earlandi. C2 is a less homogeneous group formed by stations 1, 3 and 10 with A. tepida and Q. lamarckiana as dominant species, and stations 2 and 11, with A. tepida and Q. miletti as dominant species. The C3 is formed by stations 4, 5, 6 and 9, composed of A. tepida, Q. lamarckiana and Q. patagonia. In the innermost part of the Potengi River group C4 is formed by stations 12, 17 and 18 which have few species and a predominance of A. tepida, Bolivina striatula and Q. patagonica. The group C5 is composed by station 13 and 16, and presents A. tepida, B. striatula, Q. miletti as dominant with the exception of station 14 which presented the co dominance of Gaudryina exilis. We conclude that granulometry is the main factor controlling the distribution of foraminiferal species. Also, other factors such as marine waters influence and the presence of pollution were important for the diversity and abundance of foraminifera, allowing the four sub environments. The first one is related to the estuary of the Potengi river, between the Captain of Ports and Igapó Bridge, with low diversity of species tolerant to low salinities, as Gaudryina exilis and Ammotium salsum, the second sub environment, located near the mouth of the Potengi River and adjacent continental shelf, presents higher diversity of species due to marine influence where Discorbis williamsoni and Hanzawaia boueana dominates. The two other sub environments are related to the pollution showing slight degradation signal that probably are due to the carciniculture with Ammonia tepida, Bolivina striatula, and Quinqueloculina miletti as dominat species, and another area with Ammonia tepida, Bolivina striatula, and Q. patagonica most influenced by domestic sewage from Baldo channel.

Figure 2: Four sub environments and its dominant foraminiferal species: A. low salinity tolerant species: (1) Gaudryina exilis and (2) Ammotium salsum. B. high salinity tolerant species: (3) Discorbis williamsoni and (4) Hanzawaia boueana. C. carciniculture: Ammonia tepida (5), Bolivina striatula (6), and Quinqueloculina miletti (7). D. Domestic sewage: A. tepida (5), B. striatula (6), and Q. patagonica (8). Bathymetric chart modified from Frazão (2003).

FRAZÃO, E.P. 2003. Caracterização hidrodinâmica e morfo-sedimentar do estuário Potengi e áreas subjacentes: Subsídios para

controle e recuperação de ambiental no caso de derrames de hidrocarboneto. Dissertação (mestrado) – Universidade Federal do Rio Grande do Norte. Centro de Ciências Exatas e da Terra. Programa de Pós-Graduação em Geodinâmica e Geofísica.


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Paleoenvironmental and Paleoceanographic Changes Across the Cenomanian-Turonian Boundary Event (Oceanic Anoxic Event 2) as Indicated by Foraminiferal Assemblages from the Eastern Margin of the Cretaceous Western Interior Seaway Khalifa Elderbak1; R. Mark Leckie1 and N.E. Tibert2

1University of Massachusetts Amherst, Amherst MA, 01003 2University of Mary Washington, Fredericksburg, VA 22401 [email protected] Cretaceous rocks deposited in the Western Interior Seaway (WIS) form a wedge of strata that greatly diminish in thickness eastward. During the late Cenomanian and early Turonian, the Greenhorn transgression flooded the North America foreland basin to form a relatively shallow seaway. This allowed the deposition of rhythmically bedded sequences including organic-rich strata of the Greenhorn Formation and its equivalents. Planktic and benthic foraminiferal assemblages have been effectively utilized to interpret the paleoenvironments and paleoceanography of most parts of the WIS. However, there are few such studies from the eastern part of the seaway. Two sites near the eastern margin of the seaway have been investigated. The section at Cuba, KS is about 630 km east of the Rock Canyon, CO section, and the section near Sioux City, IA is about 315 km northeast the Cuba site. Surprisingly, planktic foraminifera dominate all the studied samples despite the relative proximity of the sites to the paleo-shoreline and presumed neritic water depths (Fig. 1). This observation suggests inhospitable benthic environments. Moreover, benthic foraminiferal assemblages support the fact that seafloor oxygen deficiency in the WIS increased eastward, which argues against the hypothesis of a western margin freshwater influx and the formation of the freshwater cap. Benthic foraminifera are scarce in most studied samples with low species diversity. In the Cuba section, diversity and abundance increase abruptly in the uppermost Cenomanian “Benthonic Zone” at the initiation of the δ13Corg positive excursion marking the onset of Oceanic Anoxic Event (OAE2). In the Sioux City section, however, the benthonic zone is recognized only by an abrupt increase in the proportion of the infaunal species Neobulimina albertensis; other benthic taxa are very rare or absent. The favorable conditions of the benthonic zone were short-lived. While relatively diverse planktic foraminiferal assemblages, including keeled species, characterize the initial δ13C excursion at the Cuba site, dwarfed specimens of Heterohelix and Hedbergella dominate the assemblages at the more proximal Sioux City site. Furthermore, most of the biostratigraphic events recognized in the basin center (Rock Canyon) can be traced into the Cuba section but not into the Sioux City section. These include the Rotalipora and Globigerinelloides bentonensis extinctions, Heterohelix shift event, and the brief benthic recovery event. Correlation between the two eastern seaway sites shows thicker sections in the Sioux City site suggesting a major sediment source to the east. This may explain the inhospitable benthic conditions and development of a ‘dead zone’ analogous to the modern shelf of the northern Gulf of Mexico proximal to active discharge of the Mississippi River. Development of estuarine circulation provided the eastern part of the basin with input of calcareous plankton from the south including planktic foraminifera. Foraminiferal assemblages, total organic carbon (TOC), and δ13C data of the studied sections suggest a two-fold history of Greenhorn transgression and OAE2 development. The initial phase is a global signal characterized by a positive δ13C excursion, low TOC values, and high foraminiferal species diversity. The second phase is characterized by overprinting by local conditions in the seaway, including high fluvial input, relatively high TOC values, and low foraminiferal species diversity. These finding suggest that the eastern margin records unique depositional and biotic environments further revealing the dynamic and complex nature of the WIS and its sedimentary cycles.


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Figure 1. A west-east transect cross-section from central to eastern margin of the WIS. Foraminiferal assemblage data from the three studied sites showing significant decrease in the proportion of benthics eastward. Santonian–Campanian (Late Cretaceous) Planktonic Foraminiferal Turnover, Depth Ecology and Paleoceanographic Implications Francesca Falzoni1, Maria Rose Petrizzo1, Brian T. Huber2, and Kenneth G. MacLeod3 1Dipartimento di Scienze della Terra “A. Desio”, Università degli Studi di Milano, via Mangiagalli 34, 20133 Milano, Italy. 2Department of Paleobiology, MRC NHB 121, Smithsonian National Museum of Natural History, Washington, D.C. 20013-7912, U.S.A. 3Department of Geological Sciences, University of Missouri, Columbia, Missouri 65211-1380, U.S.A. [email protected]; The Santonian–Campanian time interval is a transitional phase from the extreme greenhouse warmth reached during the Turonian to more temperate conditions and to a thermohaline circulation that was more like that of the modern day. These environmental changes led to a re-organization of marine ecosystems in deep-sea and surface waters and to the formation of well-developed faunal bioprovinces. This environmental instability likely led to a major faunal turnover among planktonic foraminifera including extinction of the genera Marginotruncana and Dicarinella and diversification within the genera Globotruncana, Globotruncanita and Contusotruncana (Premoli Silva and Sliter, 1999). Relatively few studies on the composition of Santonian-Campanian planktonic foraminiferal assemblages are available in the literature, and those have never been coupled with reliable species-specific stable isotope (δ13C and δ18O) analyses, mainly because: (1) DSDP (Deep See Drilling Project), ODP (Ocean Drilling Program) and IODP (Integrated Ocean Drilling Program) cruises recovered relatively few and discontinuous stratigraphic sequences belonging to this interval, and (2) planktonic foraminifera from deep-sea sites are often diagenetically altered and do not yield reliable isotopic records of paleoenvironmental conditions. The unusual recovery of pristinely preserved planktonic foraminifera from Santonian–Campanian sequences in southeastern Tanzania (Tanzania Drilling Project, TDP Sites 28 and 32, see Jiménez Berrocoso et al., 2012), allowed


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examination of faunal changes and well resolved species-specific stable isotope (δ13C and δ18O) data. These data are ideal for inferring paleoecological preferences of different species and for tracing major paleoceanographic changes. Results obtained from TDP material have been compared with δ13C and δ18O values inferred from specimens recovered at two low-to-mid latitude sites (1) Shatsky Rise (ODP Leg 198, Hole 1210B; northwestern Pacific Ocean) and (2) Exmouth Plateau (ODP Leg 122, Hole 762C; eastern Indian Ocean) to detect possible shifts in species habitat preferences in different paleoceanographic contexts. At all the examined localities, we recognize consistent changes in the composition of planktonic foraminiferal assemblages that enable subdivision of the stratigraphic records into faunal intervals, each one characterized by a distinctive taxonomic composition. With the exception of the extinction of the typical Santonian fauna (marginotruncanids, dicarinellids), most of the observed compositional changes did not occur synchronously among sites, suggesting that changes were likely driven by local rather than global forces. The stable isotopic results suggest consistent depth stratification and other paleoecological differences among species. In agreement with other recent studies, our results show that the depth-distribution models based on shell morphology and analogies with modern taxa are not applicable for Cretaceous planktonic foraminifera. Combined geochemical and paleontological observations suggest that during the late Campanian the water column in Tanzania was well stratified with a deep thermocline and a thick mixed layer whereas less stratified and/or mesotrophic conditions prevailed at least in some intervals at Shatsky Rise and Exmouth Plateau. Jiménez Berrocoso A., Huber B.T., MacLeod K.G., Petrizzo M.R., Jacqueline A. Lees J.A., Ines Wendler I., Helen Coxall H.,

Mweneinda A. K., Falzoni F., Birch H., Singano J.M., Haynes S., Cotton L., Wendler J., Bown P.R., Robinson S.A., Gould J. (2012). Lithostratigraphy, biostratigraphy and chemostratigraphy of Upper Cretaceous and Paleogene sediments from southern Tanzania: Tanzania Drilling Project Sites 27 to 35. Journal of African Earth Sciences, v. 70, p. 36-57

Premoli Silva and Sliter, 1999. Cretaceous paleoceanography: evidence from planktonic foraminiferal evolution. In E. Barrera, and C. C. Johnson, eds. The Evolution of the Cretaceous Ocean-Climate System. Special Paper of the Geological Society of America 332:301–328.

Teaching Micropaleontology with Data: Gulf of Mexico “Dead Zone” Martin B. Farley Dept. of Geology & Geography, University of North Carolina-Pembroke, Pembroke, NC 28372, [email protected] Most undergraduates taking historical geology or paleontology will not become professional micropaleontologists, but they would benefit from knowing how microfossils can be used to solve geological problems. It would further benefit the field if teaching activities using microfossil data were available to the broader community. It is much easier for a micropaleontologist to use or modify existing activities than make similar ones from scratch. Further, as an optimist, I continue to hope invertebrate paleontologists will incorporate micropaleontology in their general paleontology courses. This will only happen, however, if they have access to readymade activities. Therefore, we will need to develop a method to make micropaleontologic teaching activities available to broad audiences. Micropaleontology has a wealth of data that can be used for teaching activities. An accompanying mini-poster will outline some activities micropaleontologists have already developed that are available on the Web for all to use. A particularly valuable approach is to have students use real data to address a scientific question. As an example, I have made an exercise on the zone of hypoxia (“dead zone”) in the Gulf of Mexico using the data of Lisa Osterman and colleagues at the U.S. Geological Survey (e.g., Osterman, et al., 2008). Goals of the Gulf of Mexico “dead zone” exercise are: 1) Making graphs (including having depth increase down and multiple graphs whose scales are about the same to ease comparison); 2) comparing graphs and analyzing them; 3) recognizing the geographic context of data; and 4) evaluating age models. Since most students use Microsoft Excel, this also gives them an opportunity to wrestle with the complexity of getting decent graphs out of Excel. This zone has been recognized in the last 20 years as an area of the Gulf with low-oxygen conditions that kill or drive away biota. The size of this area depends on Mississippi River discharge and has been attributed to anthropogenic fertilizer and manure runoff in the river drainage. As historical scientists, we wonder whether this has been happening all along and just happened to notice now or if this is a new phenomenon. To test this idea requires the acquisition of suitable historical data that only the sediment record can provide. Osterman’s data comes from three gravity cores and one box core that were taken within the region of modern hypoxia, on its edge, and outside. Students calculate the proportion of low-oxygen tolerant benthic forams and plot this against depth in each core. They analyze trends within each core and compare cores to each other. I also ask them to consider if peaks before the last few years can be related to historical Mississippi River floods.


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Osterman, L.E., Poore, R.Z., Swarzenski, P.W., 2008, The last 1000 years of natural and anthropogenic low-oxygen bottom-water

on the Louisiana shelf, Gulf of Mexico: Marine Micropaleontology, v. 66, p. 291-303. Ostracodes, Charophytes and Palynomorphs Integrated Biostratigraphy of the Upper Cretaceous in Santos Basin, Brazil Gerson Fauth1, Alessandra da Silva dos Santos1, Carlos Eduardo Lucas Vieira1, Cristianini Trescastro Bergue1, Simone Baecker Fauth1, Elizabete Pedrão Ferreira2, Marta Cláudia Viviers2, Javier Helenes Escamilla3, and Marcelo de Araújo Carvalho4, 1 ITT FOSSIL, Instituto Tecnológico de Micropaleontologia, Universidade do Vale do Rio dos Sinos, Av. Unisinos, 950, 93022-000 São Leopoldo, Brazil, [email protected] 2 CENPES/PETROBRAS, Setor de Bioestratigrafia e Paleoecologia, Rua Horácio Macedo, 950, Ilha do Fundão, 21941-915 Rio de Janeiro, Brazil. 3 Centro de Investigación Cientifica y de Educación Superior de Ensenada, Tijuana, 3918, Encenada-BC, Mexico. 4 Laboratório de Paleoecologia Vegetal, Museu Nacional, Quinta da Boa Vista s/n, São Cristovão, 20940-040 Rio de Janeiro, Brazil. In the Santonian–Campanian interval of Santos Basin planktic foraminifers and calcareous nannofossils render low resolution, inasmuch as the shallow platform and slope deposits changed from a retrogradational to a progradational stacking, corresponding to Santos, Juréia and Itajaí-Açu Formations. In this work, 2054 cutting samples from 14 wells were studied. Hundred nineteen ostracode species were recorded, being 90 marine and 29 paralics, mostly Trachyleberididae (21 genera) and Cytherideidae (four genera). The assemblages composition varies in abundance, diversity and richness. The paralic ones are very abundant, have low diversity but high richness, while the marine ones have higher diversity of genera and families, usually with low richness. In relation to the charophytes, 24 species were identified, usually represented by either abraded or fragmented specimens. The low abundance reinforces their allochthoneity. Seven ostracode zones were proposed, being four marine and three paralic. The study of the charophytes allowed the proposal of two biozones. The biostratigraphic model proposed herein is calibrated with the zonal schemes for palynomorphs. Paralic ostracodes from the Santonian–Campanian interval are abundant and rendered good stratigraphic resolution. The marine ostracodes allowed also to propose zones in the Santonian – Maastrichtian interval. It is usually stated that ostracode biostratigraphic zones are essentially local. However, the results of this study demonstrate that, at least in part, this is not true especially for the marine taxa, because some taxa allowed correlations between basins such as Brachycythere, Wichmanella and Majungaella. The more accurate biostratigraphic result of this study was reached with Fossocytheridea. The environmental dynamics typical of coastal areas is suitable for speciation processes and the occurrences of Fossocytheridea in Santos Basin constitutes a good example with three defined zones. The integration of ostracodes, charophytes and palynomorphs data is useful for biostratigraphic purposes despite the preliminary taxonomic knowledge of these fossils. Influence of Climate and Eustacy on Gulf of Mexico Sediment Yield During the Last Glacial Cycle Based on Palynological Analysis Shannon Ferguson ([email protected])1, Sophie Warny1, and John B. Anderson2 1Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 2Department of Earth Science, Rice University, Houston, TX Fluvial sediment transport to a basin is largely controlled by variables such as topography, compaction, lithology, hydrodynamics, and vegetation cover. Numerous stratigraphic and physiographic studies focusing on the Quaternary have been conducted in the Gulf of Mexico creating a very rich depositional framework. However, very few studies have been devoted to scrutinizing high-resolution climatic changes for Texas’ coast and the impact these changes have on coastal dynamics and margin depositional sequences. An analysis of the relationships between climate, eustasy, and sediment yield in the Gulf of Mexico is herein conducted for the last glacial cycle (LGC) by pairing published sedimentological data (Anderson et al., 2012; Anderson et al., 2008; Simms et al., 2008; Rodriguez et al., 2008) to new palynological data along the Texas coast. High-resolution (1 ky) samples are being analyzed for three characteristically different Texas bays: Trinity, Corpus Christi, and Rio Grande. These bays share similar shelf morphologies but represent varying amounts and rates of discharge, sediment loads, and drain climatically different regions. Sequence stratigraphic models using the cores combined with seismic data from the study locations have been previously worked on, but have remained incomplete without an accurate determination of how continental climate and vegetation cover affect sediment supply from different rivers during the same sea-level cycle. The new study will allow us to (1) evaluate the climate and water-


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depth changes during the last 125,000 years, especially during the last glacial maximum (18,000 years), and to (2) analyze the influence of climate and sea-level fluctuations on sediment discharge from rivers into the Gulf and the associated environmental impact on coastal morphology. Identifying the Depositional Facies in Reservoir and Resource Play Deposystems: A New Mapping Approach Based on Conventional Biostratigraphic Data Richard H. Fillon, Earth Studies Group, [email protected] A strategy of using maximum interval accumulation rate mapping based on legacy conventional biostratigraphic “tops” data that has been chronostratigraphically calibrated to geological time scale data to predict the locations of areas with greater inherent micro-porosity and permeability that are likely to be better suited for efficient resource play development has been tested on the prolific Haynesville/Bossier system. The giant Haynesville gas field occupies large portions of eleven counties and parishes in East Texas and Central Louisiana and has been heavily drilled. It is apparent from an analysis of the mapped maximum Haynesville/Bossier interval accumulation rate patterns based on conventional well data predating the resource play drilling that the Haynesville/Bossier deposystem in the broader Texas - Louisiana region is represented by three accumulation rate defined facies types. These include: high accumulation rate strata, probably representative of deltaic depocenters; intermediate accumulation rate strata representing what appear to be large prodeltaic aprons; and, low accumulation rate strata probably representing distal prodeltaic and hemipelagic drape. The mapped data clearly show that the area within the boundaries of the giant Haynesville gas field is overwhelmingly represented by intermediate accumulation rate strata. This makes a great deal of geologic sense because high accumulation rate deltaic facies are more likely to contain conventional reservoirs and low accumulation rate distal prodeltaic/hemipelagic drapes are likely to be too thin and fine grained to provide the best resource play potential. Because this approach to better characterizing resource play potential utilizes preexisting biostratigraphic well data it can be pursued as a regional exploration planning tool supplementing traditional well log correlation and mapping well ahead of the seismic acquisition phase of resource play definition. Benthic Foraminifers as Paleodepth Indicators in the Miocene of Chile: A Review of the Traditional Method and Conflicting Interpretations Kenneth L. Finger University of California Museum of Paleontology, 1101 Valley Life Sciences Building, Berkeley, CA 94720-4780 USA; [email protected] Benthic foraminifera have been used as paleodepth indicators for nearly 80 years with varying degrees of success. The traditional method of paleobathymetric determination for the Cenozoic is based on the upper-depth limits (UDLs) of species inhabiting the modern ocean. Ideally, the fossil species will be extant, but similar morphotypes can be used on the assumption that they inhabit similar depths. Their modern depth ranges were first related to depth-related physico-chemical parameters (i.e., light penetration, temperature, dissolved oxygen, stratification of the water, pressure, and CCD), and then attributed to the distribution of water masses. Physico-chemical factors and foraminiferal distributions, however, often do not coincident with water mass boundaries, and it has subsequently been shown that organic flux has a major influence on distributions in deep water. This procedure of paleodepth reconstruction has been criticized mainly because species depth ranges vary geographically. Thus, the concept of isobathymetric species was largely abandoned, and the method instead relies on using modern provincial data as a template for the past.


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There are two depth zonations that have been widely used in foraminiferal studies (table 1): one specific to the tectonic margin of the East Pacific, championed by the California school (e.g., Ingle 1980), and the other presented by Morkhoven et al. (1986) in their book on cosmopolitan deep-water foraminifers, which is biased toward passive ocean margin. It is important to recognize that both depth zonations are imperfect because the parameters that control bathymetric distributions of foraminifers also vary geographically and temporally. The most significant differences between the two schemes are in the lower part of the bathyal realm, where the zones are offset by as much as 2000 m. Regardless of which zonation is used, it would be prudent to simply consider the zones relative to one another rather than the exact numerical depths assigned to them. This avoids conflict with regional geologic concepts based on modern scenarios. Upper depth limits of benthic foraminifers serve another purpose. They enable us to recognize mixed-depth assemblages resulting from reworked or displaced sediments. An application of this paleodepth method to Miocene assemblages from south-central Chile is discussed. Local geologist have posed two arguments against the method, claiming that the most common species in an assemblage indicate the depositional environment, and upwelling can transport deep-water benthic foraminifers into shallower environments, but both are scientifically invalid concepts. Changes in Benthic Foraminifera and Sedimentary Facies Distribution of the Abu Dhabi (UAE) Coastline Over the Last 50 Years

Flavia Fiorini & Stephen W. Lokier Petroleum Geosciences Department, The Petroleum Institute, P.O. Box 2533, Abu Dhabi, United Arab Emirates. [email protected] Temporal changes in Recent benthic foraminifera and sedimentary facies distribution along the coastline of Abu Dhabi, United Arab Emirates (UAE) were assessed. The northern coastline of the UAE is undergoing massive infrastructure development with coastal engineering taking place at an unprecedented scale. Anthropogenic activities are drastically modifying the morphology of the coastline with consequent changes to hydrodynamic regimes and coastal sedimentary systems.

During the early 1960’s, prior to any major construction activities, a number of studies examined the distribution of shallow-marine foraminifera and sedimentary facies in the shallow off-shore coastal zone of Abu Dhabi (Murray, 1965, 1966a, 1966b, 1970). These earlier papers provide a good overall assessment of the distribution of sedimentary facies and index biota distribution prior to the onset of significant anthropogenic activities. We have adopted the data from these earlier studies as a ‘pre-anthropogenic base-line’ which can be used to assess the modifications in the distribution of benthic environments and consequent changes in sedimentary facies. The present study revisited, where possible, the sampling sites used in the studies conducted in the middle of last century. In total, 100 sea-floor sediment samples were collected, these represent a wide-range of shallow-marine sedimentary environments (including nearshore shelf, beach front, channels, ooid shoals and lagoonal settings) proximal to the coastline of Abu Dhabi Island. Samples were collected at a water depth of 1 to 15m in water with a temperature of 22-29˚C and a salinity of 40-46‰.

The identified foraminifera consist mainly of species with a porcellaneous test belonging to the genera Quinqueloculina, Triloculina, Spiroloculina, Sigmoilinita. Larger benthic foraminifera mainly belonging to the genera Peneroplis and Spirolina are particularly abundant in samples collected on seaweed. Hyaline foraminifera mostly belonging to the genera Elphidium, Ammonia, Bolivina and Rosalina are also common together with Miliolidae in the nearshore shelf and beach front. Agglutinated foraminifera (Clavulina, Textularia, Ammobaculites and Reophax) are present in low percentages. Among the agglutinated foraminifera the species belonging to the genera Ammobaculites and Reophax are present only in the finest grain samples and have not reported previously in the studied area.

The living (Rose Bengal stained) foraminifera represent less than 10% of the total assemblage in most of the samples. The majority of the oolith shoal sediments, the coarser sediments of the beach front and samples collected in dredged channels do not contain living foraminifera and the dead assemblage is mostly composed of a few specimens of coarse sized Miliolidae with fragmented or abraded tests, probably transported from the nearby environments.

While the shallow-water settings of the Abu Dhabi coastline continue to be areas of active carbonate sedimentation, there have been distinct, and sometimes profound, changes in facies distributions. Some settings have been totally


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lost, with sites formerly in lagoons now being under buildings, whilst other areas show surprising resilience to anthropogenic activities with little, if any discernable change in sedimentary facies distributions.

The major changes in the benthic foraminiferal assemblages over the last 50 years were the following:

• The opportunistic genera Ammonia and Elphidium have become more abundant. Reophax and Ammobaculites are reported in the area for the first time.

• With anthropogenic activities some environments, such as inner lagoons or mangroves are lost. • No living foraminifera are found in dredged channels.

The detailed analysis of these changes in foraminifera distribution and sedimentary facies allows us to further our understanding of the effects of anthropogenic activities on shallow-marine environments. By so doing, we are better able to distinguish between those changes that result from anthropogenic activities and those that are a result of naturally-occurring environmental perturbations.

Murray, J.W. (1965) The foraminiferida of the Persian Gulf. 2. The Abu Dhabi Region. Palaeogeography, Palaeoclimatology, Palaeoecology, 307-332.307-332

Murray, J.W. (1966a) The foraminiferida of the Persian Gulf. 3. The Halat Al Bahrani region. Palaeogeography, Palaeoclimatology, Palaeoecology, 59-68.59-68

Murray, J.W. (1966b) The foraminiferida of the Persian Gulf. 5. The shelf off the Trucial Coast. Palaeogeography, Palaeoclimatology, Palaeoecology, 267-278.267-278

Murray, J.W. (1970) The foraminiferida of the Persian Gulf. 6. Living forms in the Abu Dhabi region. Journal of Natural History, 55-67.55-67

Foraminiferal Paleoecology Across the Early-Middle Eocene Transition (EMET) in the Western Caribbean Richard H. Fluegeman and Michele A. Chezem Department of Geological Sciences, Ball State University, Muncie, IN 47306-0475 USA, [email protected] The early to middle Eocene transition (EMET) represents a time between 50 and 48 Ma when the Earth had a warm, but not extreme, climate. It follows a significant hyperthermal event, the Paleocene-Eocene Thermal Maximum (PETM), at approximately 55 Ma and precedes the development of the first Antarctic glaciation at approximately 40 Ma. The EMET, however, does not represent a simple transition from “greenhouse” to “icehouse” climate modes. The Calle G (Avenida de los Presidentes) section in northwestern Cuba consists of early to middle Eocene age chalks of the Capdevila, Toledo, and Principe Formations. These rocks contain a diverse foraminiferal assemblage dominated by planktonics. The planktonic foraminiferal fauna is characterized by quantitatively abundant subbotinids and acarininids. The Capdevila Formation is correlated with biozone E7a based on the presence of Astrorotalia palmerae and the absence of Turborotalia frontosa. The Toledo Formation contains T. frontosa in the absence of A. palmerae and is correlated with biozone E7b. The Principe Formation contains Guembelitriodes higginsi and Subbotina crociapertura among others and is correlated with biozone E8. The Ypresian-Lutetian boundary is placed within the lower Toledo Formation by correlation with the Lutetian Stage GSSP at Gorrondatxe, Spain. The benthic foraminiferal assemblage throughout is characterized by species of Chrysalogonium, Siphononodosaria, Nutallides, Gyroidinoides, and Cibicidoides. Oxygen isotopes were obtained from the planktonic foraminiferan Acarinina collactea through the Calle G section. The resultant curve (Figure 1) shows widely fluctuating values during the early portion of the EMET with more stable values occurring in the middle Eocene. A record of the paleoecologic index tau (total number of foraminifera species x the % planktonics) through the Calle G section produced a similar curve (Figure 2). The presence of fluctuating values of oxygen isotopes and tau followed by relatively stable values across the EMET in the Calle G section may be a local record in western Cuba or it may be related to a change in regional circulation patterns through the Caribbean Sea through the EMET. In order to evaluate the paleontological record of the Calle G section in a regional context, two additional sections across the EMET in the western Caribbean were examined: ODP site 998 B on the Cayman Rise, and ODP site 999 B in the Colombian basin. The EMET at both ODP site 998 B and ODP 999 B is represented by a series of foraminiferal limestones. Individual foraminifera could not be extracted from the core thus oxygen isotope studies could not be conducted. Thin-section studies of the limestones in the cores revealed abundant planktonic foraminifera which provided paleoecologic information. The ratio of Morozovella and Morozovelloides to other planktonic foraminifera was tabulated for each sample. Morozovella and Morozovelloides are associated with warm, subtropical waters and the abundance of these two genera can serve as a proxy for paleoceanographic changes at each site. The Morozovella:totalplanktonics ratio obtained at ODP site 998 (Figure 3) shows high, fluctuating values in the early part of the EMET with low, stable


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values during the middle Eocene. The Morozovella:total planktonics ratio obtained at ODP site 999 (Figure 4) is similar to that of ODP site 998 showing high, fluctuating values in the early part of the EMET with low, stable values in the middle Eocene. The presence of fluctuating values of oxygen isotopes, tau, and the Morozovella:total planktonics ratio followed by stable values of each across the EMET provides evidence of a regional shift in ocean circulation patterns in the western Caribbean region. While not identical, the patterns of the diverse paleoecologic parameters may be related to a change in circulation patterns through the Caribbean caused by a developing oceanic gateway. Foraminiferal records from piston cores on Beata Ridge through the early and middle Eocene show a transition from a pelagic to a neritic environment. Additionally, DSDP site 151 on the southern Beata Ridge has an unconformity between the middle Oligocene and lower Eocene sections. It seems likely that Beata Ridge developed as a positive feature during the EMET and may have functioned as an oceanic gateway into the late Eocene. The paleoecologic records of foraminifera in the western Caribbean are likely related to the development of a regional ocean gateway rather than broad global change in paleoclimate.

Figure 1. Figure 2.

Figure 3. Figure 4.


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20,000 Forams under the Sea: Reconstructing Climate Variability in the Middle Miocene using Planktonic Foraminifera from the Equatorial Pacific Ocean (IODP Site U1338) Lyndsey Fox1, Bridget Wade1, Ann Holbourn2, and Melanie Leng3 1School of Earth and Environment, University of Leeds, Leeds, LS2 9JT. 2Institut für Geowissenschaften Christian-Albrechts-Universität zu Kiel, Ludewig-Meyn-Straße 14, 24118 Kiel. 3British Geological Survey, Keyworth, Nottingham, NG12 5GG. The middle Miocene (17-13.5 Ma) was the warmest interval of the Neogene. During the early to middle Miocene (23-11.5 Ma) the climate fluctuated greatly, with cyclic periods of Antarctic glaciation and climatic warming termed the “mid Miocene climate optimum”. Integrated Ocean Drilling Program Expedition 320/321 recovered lower-middle Miocene sediments with high sedimentation rates (30m/myr), continuous recovery, and orbital cyclicity from the equatorial Pacific. Previous studies of the lower interval have been hindered by the absence of biogenic carbonate (e.g., Leg 199). However at Site U1338 planktonic foraminifera are abundant in the lower and middle Miocene sediments and scanning electron microscopy has shown that foraminifera are well preserved and diverse (Fox and Wade, submitted), allowing for studies of planktonic foraminiferal stable isotopes, biostratigraphy, and biotic evolution. Despite extensive studies of benthic foraminifera, existing planktonic foraminiferal records of this interval are extremely scarce and of low resolution, with samples representing time intervals of 2x105and 5x105 years. Specimens from U1338 of Globigerinoides subquadratus and Globigerinoides spp. are analysed at 10cm intervals providing 3 kyr resolution. Here we present the initial results as we endeavour to produce the first orbital scaled record of δ18O and δ13C variability throughout 17-13.5 Ma as well as an overview of foraminiferal assemblages from the middle Miocene, examining the preservation and potential for future studies of foraminiferal evolution. Fox, L. R., Wade, B. S. 2012. Systematic taxonomy of early–middle Miocene planktonic foraminifera from the equatorial Pacific

Ocean: Integrated Ocean Drilling Program, Site U1338. Journal of Foraminiferal Research (submitted). FACTbase: A New Solution for Foram Identification Andrew J. Fraass†, Serena Dameron†, Jonathan Leachman†, Christopher Lowery†, Stephen A. Nathan†, and R. Mark Leckie† †FACTbase L.L.C. [email protected] Identifying unknown foraminiferal species can be difficult and time consuming. To alleviate this, we have developed FACTbase, a foraminiferal database that includes images as well as detailed morphologic information. Users can search on visual characteristics that are logged in the database, such as type of coiling, number of chambers, test shape, and type of aperture thereby facilitating rapid identification of a taxon right at your computer without a pile of open books around your microscope. A simple morphology-based search interface replaces the endless thumbing through of references by displaying a list of possible taxa with images and short descriptions. FACTbase also serves as a taxonomic clearinghouse, tracking changing names and species concepts. Taxa have entries with detailed information, including their taxonomy and synonymy, type location and level, original reference, diagnostic description and discussion, stratigraphic range, basic ecologic information, images of the holotype, and images published by DSDP/ODP/IODP and other sources. Over 300 unique characteristics are logged within the database, with each being a possible search criterion; these include wall types, ornamentation, chamber style, apertural characteristics, etc. All information is linked directly to a specific reference, sourced from atlases, journal articles, and book chapters. FACTbase is also designed to be flexible to change along with new species and synonymy, and in the future to dynamically respond to an individual workers preference for one name over another. Future plans include customizing the database to suit the needs of individual users, whether industry, consultant, or academic; deployment with the IODP; and pairing with academic labs to aid in taxon entry with a work-for-access program. FACTbase is a foraminiferal database, but the structure could be customized for other microfossil groups. Currently, FACTbase has focused on Cenozoic planktic and benthic foraminifera, with a particular emphasis on deep-water species of the Gulf of Mexico and Caribbean. The database can be customized for basin-specific needs.


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Preliminary Foram Biostratigraphy and Organic Biomarker Paleotemperature Results from Site U1396, IODP Exp. 340 Andrew Fraass†, Isla Castañeda†, V. Phu†, R.Mark Leckie†, and Exp. 340 Scientific Party †University of Massachusetts - Amherst [email protected] During the Pliocene major changes in global climate and oceanography occurred due to closure of the Central American Seaway (CAS) and the intensification of Northern Hemisphere glaciations. Currently, many outstanding questions remain regarding the re-organization of oceanic circulation during this time. Here, we apply a multiproxy approach to examine sediments from Site U1396 from IODP Expedition 340 (Lesser Antilles Volcanism and Landslides), situated in the eastern Caribbean, which presently falls under the influence of the North Equatorial Current. This site presents an excellent opportunity to test both the new tropical planktic foraminiferal biostratigraphic calibration of Wade et al., 2011 and to investigate the temperature of the past ~4.52 myr from the Montserrat region. After correlating Holes A and C, planktic results largely corroborate the order of bioevents from Wade et al., 2011 and the nearby Site 999 (Chaisson and D’Hondt, 2000), however secondary marker species Globorotalia flexuosa, Gr. crassaformis, and Gr. pertenuis have lowest occurrences that extend below their expected First Appearance datums, while Globigerinoides extremus and Pulleniatina primalis were found to have anomalously high ranges reflecting regional influences. Sedimentation rates derived from this revised Hole U1396-A and -C biostratigraphy show the same trend as shipboard work: faster sedimentation in the lower Pliocene, slowing towards the Holocene. Two organic geochemical paleothermometers, the Uk’

37 Index and TEXH86, were utilized to examine Plio-Pleistocene

SST variability. While the Uk’37 Index is at unity in many samples and is thus somewhat insensitive to temperature

change at this tropical site, the TEXH86 record displays more variability. A significant cooling is noted in TEXH

86 SST at ~4.1 Ma based on the preliminary age model, coinciding with significant changes in foraminiferal abundance, which may be related to changes in ocean circulation associated with an important transition in the closure of the central American Seaway (e.g., Steph et al., 2010). Overall, application of organic geochemical paleothermometers appears to be a promising technique for examining the Pliocene SST evolution of the Caribbean, particularly since these proxies are not influenced by salinity to the extent observed in δ18O or Mg/Ca ratios of foraminifera. Chaisson, W.P., and D'Hondt, S.L., 2000. Neogene planktonic foraminifer biostratigraphy at Site 999, western Caribbean

Sea. In Leckie, R.M., Sigurdsson, H., Acton, G.D., and Draper, G. (Eds.), Proc. ODP, Sci. Results, 165: College Station, TX (Ocean Drilling Program), 19–56. doi: 10.2973/odp.proc.sr.165.010.200

Steph, S., Tiedemann, R., Prange, M., Groenveld, J., Schulz, M., Timmermann, A., Nürnberg, D., Rühlemann, C., Saukel, C., and Haug, G. H., 2010. Early Pliocene increase in thermohaline overturning: A precondition for the development of the modern equatorial Pacific cold tongue. Paleoceanography, 25, PA2202.

Wade, B., Pearson, P. N., Berggren, W., & Palike, H., 2011. Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth Science Reviews.

Age and Depositional Environment of the Lower Eagle Ford Group in North Central Texas Virginia Friedman 1000 Walnut Place, Mansfield Texas 76063, [email protected] The Eagle Ford Group (Cenomanian/Turonian) is a shallow marine transgressive sequence composed for the most part of dark shales. The Eagle Ford was deposited during the mid-Cretaceous Greenhorn cyclothem which was in turn part of the Western Interior Seaway. The Eagle Ford is subdivided into a lower transgressive sequence (Tarrant ad Britton Formations) and an upper highstand sequence (Arcadia Park Formation).The Arcadia Park contains a stratigraphic marker named locally Kamp Ranch which has been interpreted as a tempestite deposit. The Britton Formation is further subdivided into lower and upper Britton. This is based mostly on calcium carbonate content. This work aims to study the lower Britton (Turner Park Member) in the Dallas-Fort Worth area based on its micropaleontological assemblage. The following foraminifers were found in the assemblage: Heterohelix moremani, Heterohelix sp., Hedbergella amabilis, H. brittoensis, H.delrioensis, Guembelitria harrisi, Schackoina cenomana, Rotalipora cushmani, and R. geenhornensis. The diversity of the assemblage is low, with abundant shallow-dwelling opportunistic species such as Hedbergella and Heterohelix and rare rotaliporiids. Since the assemblage is entirely planktic, it indicates that the bottom of the ocean was either dysoxic or anoxic creating an environment unsuitable for benthic forams to inhabit. These deposits are stratigraphically close to the C/T boundary where the last occurrences and eventual extinctions of planktic keeled


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forams such as Rotalipora cushmani and R. greenhornensis are events recognized worldwide (C/T Anoxic Event, OEA-2). In addition to the planktic microfauna present, macrofaunal remains were also recovered consisting of sharks (Cretolamna, Cretodus, Ptychodus, Squalicorax, Scapanorhyncus) and other fishes (Saurodon, Enchodus, Xiphactinus, Pachyrhizodus, Thryptodus, Protosphyraena. Countless coprolites attributed to these fish or sharks were recovered from the area. Rare reptilian remains were also found: plesiosaurs, turtles, Coniasaurus. The only benthic organisms recovered in the study area are inoceramids. It has hypothesized that these bivalves were in symbiotic association with zooxanthellae or some other microorganisms that allow them to survive in a stressed low -oxygen environment. The lower Britton is interpreted to have been deposited under low-energy (below wave base) near shore in a shallow to moderately deep quiet marine environment. The C/T boundary falls within the upper Britton (Camp Wisdom Member) but its exact position has not yet been established. The age of the sediments of the lower Britton indicate that it is close to the C/T boundary. Based on planktic foraminiferal assemblage (and on calcareous nannoplankton as backup data), the age of the lower Britton is late but not latest Cenomanian. The Late Jurassic Garantella and Reinholdella: A Paleoenvironmental Proxy and Potential Tool for Sweet-Spotting in Unconventional Plays. Rui Da Gama and Brendan Lutz Shell International Exploration and Production, Inc. [email protected]; [email protected]

In order to maximize the potential of unconventional plays, it is critical that we identify tools for accurate paleoenvironmental assessment, the recognition of key surfaces (e.g., maximum flooding surfaces and sequence boundaries), and the identification of stratigraphic intervals with higher potential for hydrocarbon recovery. Biostratigraphic proxies that can assist in sweet-spotting are therefore highly valuable and increase confidence in operational decisions. In the late Jurassic (late Oxfordian to middle Tithonian) shallow marine Louisiana Salt Basin, the distribution of benthic foraminifera from the genera Garantella and Reinholdella may provide such a proxy. An integrated analysis of biostratigraphic, chemostratigraphic, and sedimentological data suggests that this group—particularly Garantella spp.—consistently favored shallow-water (likely <150 m), well-oxygenated, mesotrophic-to-oligotrophic environments within this structurally controlled basin. Variations in the abundance of these species agree with sequence stratigraphic interpretations and reconstructions of basin architecture, indicating that localized populations flourished on topographic highs during periods of transgression and only migrated toward deeper parts of the basin during regressive phases. Garantella-Reinholdella spp. were also absent or extremely rare in deeper parts of the basin, where chemostratigraphic data indicate low bottom water oxygen and higher TOC. Hence, the distribution of this group suggests that it may serve as a useful paleoenvironmental indicator in Jurassic unconventional plays.

This work highlights the role of biostratigraphy in exploration and sweet-spotting in unconventional shale plays. Here, the spatial and temporal distribution of the Garantella-Reinholdella group assists in identifying sections that were deposited in well-oxygenated, shallow water, oligotrophic environments. In doing so, these benthic foraminifera can serve as a useful complement to other geological and geophysical tools in targeting intervals with the highest potential for economic hydrocarbon recovery. A Review of Late Oligocene to Mid Miocene Sphenolithids Rui da Gama Shell International Exploration and Production, Inc. [email protected]; The genus Sphenolithus was first proposed by Deflandre 1952, to describe a group of wedge-shaped (dome or spine-like) calcareous nannofossils consisting of radiating elements. The genus first appeared in the early late Paleocene and became extinct in the early Pliocene. During the Late Oligocene to Mid Miocene the group records high turnaround with the introduction of circa 20 new species and the extinction of 29 species and has potential for further taxonomic subdivisions.


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This study underlines the genus usefulness to providing higher resolution in the stratigraphic subdivisions of Late Oligocene to Mid Miocene sediments. In addition, it discusses species concepts, and introduces new combinations and several new variations with potential speciation value. The age ranges are described in reference to Martini 1971. The problems of species concepts and variations on the following groups are emphasized: 1) S. predistentus, S. distentus and S. ciperoensis; 2) S. aubrei, S. disbelemnos and S. dissimilis; 3) S. cf. abeis, S. aubryae (wide), S. disbelemnos; 4) S. neospiniger, S. cf delphix, S. delphix and S. tintinabulum; 4) S. delphix, S. calyculus, S. cf. calyculus and S. cometa; 5) S. cf proceros and S. proceros; 6) S. grandis, S. cf. abeis (large), S. conicus and S. arthurii. We also discuss the similarity between the Sphenolithus spine and Triquetrorhabdulus carinatus.

S. ciperoensis S. ciperoensis var. a S. distentus S. distentus var. S. predistentus S. predistentus var. a

S. aubryae S. aubryae (wide) S. disbelemnos S. disbelemnos var. a S. dissimilis S. cf. abeis

S. cf. delphix S. delphix S. tintinabulum S. calyculus, S. cometa S. procerus

S. arthurii S. grandis S. conicus S. cf. abeis (large) S. heteromorphus T. carinatus


55

Fig.1 Stratigraphic ranges of selected Late Oligocene to Mid Miocene Sphenolithid.

Biostratigraphic Framework and Paleoenvironments of the Niobrara Formation: An Integrated Approach to Reservoir Characterization. Rui Da Gama and Brendan Lutz Shell International Exploration and Production, Inc. [email protected] The Niobrara Formation—deposited during the latest Turonian to early Campanian of the Western Interior Seaway (WIS; Fig. 1)—has recently received much attention as an unconventional play. This study provides an understanding of the local stratigraphy and prevailing environmental conditions during the deposition of the Niabrara Formation. It points for an interplay of tectono-volcanism, terrigenous input, regional and global climate, and ocean circulation as the main driving mechanisms controlling sediment generation and deposition. Nannofossil, microfossil, and palynological data are used to develop a local high-resolution zonation scheme that allows the identification of regionally correlative horizons and provide a time-stratigraphic framework for the paleoenvironmental variables at the time of deposition. During the late Coniacian to earliest Santonian, the replacement of deep-dwelling, Tethyan planktonic foraminifera with shallow-dwelling Boreal forms—coeval with a significant reduction in calcareous benthic foraminifera and the onset of dominant Inoceramus spp.—indicates the development of severely dysoxic conditions within the basin. Meanwhile, palynomorphs suggest increasing terrigenous influence and overall decreasing salinity. These trends point toward a significant reorganization of climate, ocean circulation, and water column structure during this interval, as diminished vertical and lateral mixing combined with enhanced fluvial runoff promoted the development of a stagnant, stratified water column with high surface productivity and severely dysoxic bottom waters. By coupling statistical biofacies analysis with petrofacies characterization (Fig. 2), changes in rock properties are related to paleoenvironmental shifts. In particular, carbonate-rich petrofacies are linked to the transport of microfossils from suboxic regions during intervals of enhanced circulation and vertical mixing whereas shaly petrofacies with low carbonate content are more commonly associated with severely dysoxic biofacies dominated by Inoceramus spp. Through multidisciplinary integration, this reconstruction provides insight into the depositional character, paleoenvironmental dynamics and overall geologic characterization of the Niobrara Formation.


56

Figure 1. (A) Schematic of the WIS during deposition of the Niobrara Formation (modified from Roberts and Kirschbaum, 1995). (B) Cross section of the WIS showing the distribution of terrigenous siliciclastics, marine shales, and limestone (modified from Kauffman, 1977).

Figure 2. Comparison of biofaceis and petrofacies within a key interval of the Niobrara Fm. showing the influence of paleoenvironmental shifts on sedimentary deposition. Automated Fossil Analysis – Advances in Technology Allow for a Paradigm Shift in Biostratigraphic Data Collection and Analysis

Gunilla Gard1 and Anthony Gary2 BHP Billiton Petroleum1 and Tramontane, Inc2. [email protected] Biostratigraphy faces a serious challenge to maintain relevancy as it devotes too much of its resources to data generation and too little to data analysis and the information valued by consumers. Present-day methods for collecting biostratigraphic data also compromise and degrade the potential contribution of quantitative data analysis. This must change for biostratigraphy to remain relevant in the future.


57

Imbrie and Kipp (1971) and others demonstrated the potential of multivariate analysis of large amounts of quantitative data in biostratigraphy. A couple of decades followed with a flurry of activity in the application of various multivariate methods. The tremendous increase in computational power and reduction in computational costs that occurred over the following decades made possible major advances in quantitative biostratigraphic analysis; however, the potential has not been fully realized. While there have been successes in academic applications of multivariate methods, these methods have rarely been adopted by industry, in part due to the time consuming data generation.

An intrinsic and systemic problem is with how micropaleontological data is collected. In biostratigraphy, humans are the data collectors that convert the analog signal they see through the microscope to the digital signal that is computationally analyzed. There is an inherent loss of potential information in the analog to digital transformation, but when humans are the data collectors there is also the introduction of additional error and bias as well as ambiguity, and there is effectively no calibration. The cumulative effects of these factors places biostratigraphy at a competitive disadvantage relative to other geoscience disciplines, and greatly limit the potential of quantitative methods in biostratigraphy.

For quantitative analysis to yield the most useful result, species identifications must be consistent and reproducible, and if not, the classification/identification uncertainty quantified, so that species counts have a specified accuracy. The recognition of these problems is not new; they were to varying degrees the impetus for the considerable foundational work that has been done in microfossil biometrics. The earliest studies (e.g., Blackith & Reyment, 1971) applied statistical or multivariate methods to cluster or classify specimens based on characters or features measured from microfossil specimens, such as distances, angles and counts. This is an obvious advance with regard to objectivity, but the data collection is laborious and still requires humans to acquire the measurements.

Later, methods more amenable to computer-based collection of morphometric attributes of microfossils were developed. There were two predominant, and often competing (Bookstein et al., 1982; Ehrlich et al., 1983), approaches: landmark-based geometric methods, typified by eigenshape analysis and shape outline analysis, typified by Fourier series analysis in closed form. Morphometric methods and classification techniques applicable to microfossils have continued to progress, leveraging advances in other fields, such as computer technology, robotics and artificial intelligence. This rich history of applied morphometrics provides an excellent foundation for effective feature extraction from microfossils for computer-aided taxonomic classification/identification.

More recent studies have successfully demonstrated the complete automated taxonomic identification process from image acquisition to classification among different microfossil groups (e.g., France et al., 2000; Bollmann, et al., 2005; Benfield, et al., 2007). Additionally, other complementary fields of science have also made tremendous advances in automated image capture and classification systems. Operational systems have been developed for real-time, automated identification of modern phyto- and zooplankton (Benfield et al., 2007). Automated taxonomic identification has been shown by recent studies to be a realistic and defendable goal.

With a solid legacy of morphometric studies and quantitative methods, and the advances in computer technology and artificial intelligence capabilities, computer-based taxonomic identification as an operational tool can become viable in the near future. With the collection of larger and more consistent data sets, biostratigraphy can increase its applicability in solving the traditional geologic problems of age determination, correlation, paleoenvironment and sediment source. We propose that it is time for the industry to take the lead and create a collaborative effort between industry and academia to bring operational automated taxonomic identification to reality.

Bollmann, J., Quinn, P.S., Vela, M., Brabec, B., Brechner, S., Cortés, M.Y., Hilbrecht, H., Schmidt, D., Schiebel, R. & Thierstein, H., 2005, Automated particle analysis: Calcareous microfossils. Image Analysis, Sediments and Paleoenvironments, v. 7, part III, p. 229-252.

Benfield, M.C., Grosjean, P., Culverhouse, P.F., Irigoien, X., Sieracki, M.E., Lopez-Urrutia, A., Dam, H.G., Hu, A., Davis, C.S., Hansen, A., Pilskaln, C.H., Riseman, R.M., Schultz, H., Utgoff, P.E. & Gorsky, G., 2007, RAPID: Research on automated plankton identification. Oceanography, v. 20, n. 2, p. 172-187.

Blackith, R.E. & Reyment, R.A., 1971, Multivariate Morphometrics. Academic Press, London & New York. Bookstein, F.L., Strauss, R.E., Humphries, J.M., Chernoff, B., Elder, R.L. & Smith, G.R., 1982, A comment upon the uses of Fourier

methods in systematics. Systematic Zoology, v. 31, p. 85-92. Ehrlich, R.R., Pharr, Jr., R.B., Healy-Williams, N., 1983, Comments on the validity of Fourier descriptors in systematics: A reply to

Bookstein et al. Systematic Zoology, v. 32, p. 202-206. France, I., Duller, A.W.G., Duller, G.A.T. and Lamb, H.F., A new approach to automated pollen analysis. Quaternary Science

Reviews, v. 19, p. 537-546. Healy-Williams, N., Ehrilich, R. and Williams, D.F., 1985, Morphometric and stable isotope evidence for subpopulations of

Globorotalia truncatulinoides. Journal of Foraminifera Research, v. 15, p. 242-253. Imbrie, J. and Kipp, N.G., 1971, A new micropaleontological method for quantitative paleoclimatology: Application to a Late

Pleistocene Caribbean core; in Turekian (ed.) The Late Cenozoic Glacial Ages, Yale University Press, New Haven, CT, p. 71-181.


58

A Web-Based Paleoecological Database for Microfossils Gary, A.C., Yu, E. and Johnson, G.W. Technical Alliance for Computational Stratigraphy Energy & Geoscience Institute, University of Utah [email protected] The body of knowledge regarding the paleoecology of microfossils has grown considerably over the past few decades, and has produced valuable insights into climate history, estimates of surface-water productivity, distribution of biofacies, sediment sources and transport pathways, and field-scale correlation (see Leckie & Olson, 2003 and Murray, 2006 for summaries). Within industrial biostratigraphy, paleoecology is increasingly important at the reservoir-scale for infill and directional drilling (e.g., Jones & Charnock, 1985; Payne et al., 1999; Hughes, 2005; Mears & Cullum, 2009). However, the application of paleoecological information is hampered because a biostratigrapher’s knowledge is typically restricted to a particular microfossil group (i.e., ‘specialty’) and is not exhaustive, and for other microfossil groups their knowledge is limited and patchy, at best. Further, unlike taxonomic information, paleoecological information is not compiled and cataloged, so the search for relevant information can be laborious. Thus, the quality of a paleoecological interpretation is constrained by the biostratigrapher’s breadth of knowledge and the time available to search for information. To reduce these obstacles, and encourage broader dissemination and use of paleoecological information among the global community-of-practice the Technical Alliance for Computational Stratigraphy (TACS) developed – with the support of BG Group, BHP Billiton, Chevron and Shell – a paleoecological database and query application that can be web deployed. Web-deployment of the system is intended to facilitate greater collaboration between academic and industry users, and create an information store that will benefit both user groups. The paleoecological database is a unified, digital data store (relational database) for paleoecological information for the dominant microfossil disciplines that enables biostratigraphers to easily and quickly retrieve paleoecological information about the microfossil assemblages they encounter. The database system covers microfossil ecological attributes, such as life strategy (e.g., feeding strategy and mobility), spatial distribution (e.g., latitude and depth range or water column position) and physical/chemical factors (e.g., oxygen, salinity, substrate and depositional setting), among others. A database is only a container however; it is the contents that add value. So, without feeding and maintenance the database will become stale and its value will diminish over time. The challenge then, beyond an effective and adaptable database structure, is to develop and implement a process that will ensure that the database content is as complete as possible, vetted and ‘evergreen’. To address these 'content issues’ we plan to open the database to the global community-of-interest (i.e., the global community of academic and industrial micropaleontologists) for queries and contributions. To ensure broad access to the community-of-interest the database will be made available via a web-browser-based interface. Presently, a form of governance and the technology to implement it are being investigated. The objective is to balance a Wikipedia-type approach, where contributions and edits of content are open to any user, which would likely be considered too open by the micropaleontological community, and a formal structure with an editor and peer-review process that would likely stymie the rapid, free and loose exchange of information. Hughes, G.W., 2005, Micropaleontological dissection of the Shu’aiba reservoir, Saudi Arabia: in Powell, A.J. and Riding, J.B. (eds.),

Recent Developments in Applied Biostratigraphy, The Micropalaeontological Society, Special Publications, p. 69-90. Jones, R.W. & Charnock, M.A., 1985, ‘Morphogroups’ of agglutinating foraminifera, their life positions and feeding habits and

potential applicability in (paleo)ecological studies. Revue de Micropaleontologie, 4, p. 311-320. Leckie, R.M. & Olson, H.C., 2003, Foraminifera as proxies for sea-level change on siliciclastic margins: in Olson, H.C. & Leckie,

R.M. (eds.), Micropaleontologic Proxies for Sea-Level Change and Stratigraphic Discontinuities, SEPM Special Publication No. 75, p. 5-19.

Mears, P. & Cullum, A., 2009, High-pressure, high-temperature wells on the Halten Terrace, offshore Norway: the role of micropaleontology in planning and drilling wells on the Kristin Field: in Demchuk, T.D. & Gary, A.C. (eds.), Geologic Problem Solving with Microfossils: A Volume in Honor of Garry D. Jones, SEPM Special Publication No. 93, p. 9-20.

Murray, J.W., 2006, Ecology and Applications of Benthic Foraminifera. Cambridge University Press, Cambridge, 438 pp. Payne, S.N.J., Ewen, D.F. & Bowman, M.J., 1999, The role and value of ‘high-impact biostratigraphy’ in reservoir appraisal and

development: in Jones, R.W. & Simmons, M.D. (eds.), Biostratigraphy in Production and Development Geology, Geological Society, Special Publication, 152, p. 5-22.


59

Comparison of Evolutionary Patterns within Genus Discoaster in Selected Time Intervals and Correlation to Global Climate Changes Adele Garzarella1, Marina Ciummelli1 and Isabella Raffi1

1Dipartimento di Ingegneria e Geotecnologie (Ingeo) – CeRSGeo, Università “G. d’Annunzio” di Chieti-Pescara, Via dei Vestini 31, 66013 Chieti Scalo - Italy, Phone: +3908713556192, E-mail: [email protected] Calcareous nannofossils belonging to genus Discoaster are useful biostratigraphic markers, throughout their distribution range encompassing the middle Paleocene – late Pliocene time interval. The evolutionary history of genus Discoaster is assessed to be one of the most dynamic within calcareous nannofossil taxa as it recorded several extinction and speciation events (Bukry, 1971; 1973; Haq, 1971; Perch-Nielsen, 1977, 1985; Romein, 1979; Theodoridis, 1984; Backman, 1986; Raffi et alii, 1998; Agnini et alii, 2007, 2008). Moreover, the oligotrophic affinity of the genus Discoaster is widely accepted (Edwards, 1968; Bukry, 1973; Aubry, 1998; Bralower, 2002), as they are sensitive to productivity pressure and nutrient availability (Bukry, 1973; Aubry, 1992; Chepstow-Lusty, 1996). Our study focuses on the distribution patterns and evolutionary trends of selected taxa during the upper Paleocene (Atlantic Ocean, ODP Site 1262) and middle-upper Miocene (Eastern Equatorial Pacific Ocean - EEP, IODP Site U1338). Semi-quantitative analyses of calcareous nannofossil assemblages have been carried out on complete stratigraphic successions for the considered intervals. Moreover the availability of high-resolution sample sets allowed us to delineate the major evolutionary patterns within discoasters. Three lineages have been delineated within Paleocene assemblage: Discoaster mohleri – D. backmanii – D. nobilis (Fig. 1), D. backmanii – D. okadai and Discoasteroides megastypus – D. multiradiatus lineages. In middle-upper Miocene sediments, we investigated the five – rays Discoaster origin and evolution (Fig. 2), the distribution ranges of D. brouweri and Discoaster sp2, and the occurrence of “odd Discoaster” (not ascribed to known species) during times of enhanced biosilica deposition, namely diatoms, showing an intriguing correlation with near identical morphotypes recorded in upper Miocene sediments from Mediterranean (Stradner, 1973 ; Raffi et alii, 2003; Hilgen et alii, 2010). A morphometric analysis was performed to classify Discoaster species providing a clear taxonomy. We also identified intermediate morphologies between end-member species and their co-occurrence with ancestor and descendant taxa in both Paleocene and middle-late Miocene evolutionary lineages, giving an effort in understanding the evolutionary mechanisms acting on this genus. The two major evolutionary mechanisms that effected genus Discoaster were the gradual evolution between end-member species (few hundred kyr) and the sudden occurrence of new taxa (few thousand kyr). The relationships between evolution and global climate/environmental changes recorded during upper Paleocene and the different stages of the Miocene climatic transition (i.e., the development of the Eastern Antarctic Ice Sheet, the middle-late Miocene “Carbonate Crash”, and the deposition of diatom enriched sediments; Vincent and berger, 1985; Kemp and Baldauf, 1993; Lyle et alii, 1995) have been investigated through the comparison with geochemical proxies (d18O, d

13C, Fe, %CaCO3; Zachos et alii, 2010; Lyle and Backman, in press). Finally, we attempt to relate the observed major evolutionary events within Discoaster taxa to the global and local paleoenvironmental changes in such different time slices. Figure 1.

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60

Figure 2.

Correlating Shallow Marine Holocene Records Across the Strait of Magellan (53°S), Chile

M. A. Godoi 1, 2, 3, P.L.Gibbard2, and M.A. Kaminski4 1. Dirección de Programas Antárticos, Instituto de la Patagonia, Universidad de Magallanes, Punta Arenas, Chile. ([email protected]) 2. Cambridge Quaternary, Department of Geography, University of Cambridge, England 3. Centro de Estudios del Cuaternario (CEQUA), Punta Arenas, Chile. 4. Earth Sciences Department, King Fahd University of Petroleum & Minerals, PO Box 701, Dhahran, 31261, Saudi Arabia. Multiproxy records of shallow marine sediments cores from the area of Cabo Tamar and Puerto Churruca, on the eastern and western sides of the Strait of Magellan (53°S) respectively, agree well throughout the Holocene. The marginal Churruca I site (ca. 75 m water depth) better records the changes in relative sea levels, and compares closely with the findings by Porter et al. (1984) for the Holocene in this region. The sequence extends from the late stages of the last deglaciation, with sediment sources varying from clay-rich to increasingly organic through to the present. Benthic foraminifera records are dominated by different opportunistic species, and imply that fully marine conditions had been established by 9,780 ± 100 14C a BP at this site. Test sizes remain small throughout the sequence, characterising different levels of dysoxia during the Holocene. Currently, the water column at this site has an oxygen minimum zone below ca. 40 m. Across the Strait of Magellan, the closely connected sites Tamar I (80 m water depth) and Tamar II (31 m water depth) are currently well ventilated and are located in the area where the distal meltwater from the Gran Campo Nevado ice cap encounters the oceanic currents that reach the Pacific entrance of the main strait. The Holocene sequences record lower sedimentation rates, and indicate that fully marine conditions were well established here by 8,680 ± 40 14C a BP (base of one of the cores). This corresponds well with previous dates for the marine transgression at this locality (ca. 11,720 ± 60 14C a BP, Kilian et al. 2007). Benthic foraminifera assemblages present a good distribution of test sizes and include detrital material. At least two major changes in the marine palaeoenvironment of both localities can be correlated during the post-glacial, with optimum conditions occurring during the mid-Holocene. Fine substrates and infaunal species dominate all records. A clear shift towards higher species diversity and possible warmer conditions occurs coincident with the tephra of the H1 eruption of the Hudson volcano, previously dated at ca. 6850±160 14C a BP or 7571-7849 cal years

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61

BP (Stern 2008). The influence of the Antarctic Circumpolar current (ACC) starts to become apparent in this region after this event. The chronological timeframe of these sequences is still under construction. Kilian, R., O.Baeza, T. Steinke, M. Arevalo, C. Rios, & C. Schneider 2007b. Late Pleistocene to Holocene marine transgression and

thermohaline control on sediment transport in the western Magallanes fjord system of Chile (53° S). Quaternary International 161: 90-107.

Porter, S.C., M. Stuiver, & C. Heusser. 1984. Holocene sea-level changes along the Strait of Magellan and Beagle Channel, Southernmost South America. Quaternary Research 22: 59-67.

Stern, Ch.R. 2008. Holocene tephrochronology record of large explosive eruptions in the southernmost Patagonian Andes. Bulletin of Volcanology 70:435-454.

Mid Carboniferous Cyclic Sedimentation on Bear Island (Arctic Norway) Felix M.Gradstein1, Vladimir I. Davydov2, and Øyvind Hammer1 [email protected]; 1University of Oslo, Norway, 2Boise State University, ID, USA Silicilast sediments of Serpukhovian through Moscovian age on Bear Island, Arctic Norway represent a succession that is not well understood in the local Barents Sea chronostratigraphy and global time scale. Monotonous quartzitic sandstones (humid alluvial fan) of the Nordkapp Formation of Devonian age are sharply replaced by cyclic Landnørdingsvika Formation of interbedded red mudstones, yellow-brown sandstones and red conglomerates, which together represent an intricate interfingering of flood-plain, alluvial fan and marginal marine sediments. The presence of calcrete paleosols in the Landnørdingsvika Formation contrasts with the development of coals in the Nordkapp unit. The Landnørdingsvika Formation with transitional contact is replaced by the marine Kapp Kåra Formation, divided into three members: Bogevika, Efuglvika and Kobbebukta. The Bogevika Member consists of limestones, shales and sandstones apparently organized in a series of small-scale (< 10 m thick) transgessive-regressive cycles. For the first time, Early Bashkirian larger foraminifers Plectostaffella and Semistaffella were found near the base of the Bogevika Member. Middle Bashkirian Staffelaeformis staffelaeformis and Pseudostaffella ex gr. grandis were found near the top of the member. This implies that marine trangression in the western Barents Sea started about 10 Ma earlier than understood sofar. Markov chain analysis of sand-shale-limestone order relationship over 54 sedimentary levels in the Kobbebukta beach outcrop of the Bogevika Member reveals nine sedimentary cycles, totaling over 45m in thickness. A standard cycle consists of a sandy and erosive lowstand system track of fluviomarine facies, followed upwards with a coarse bioclastic limestone with oncoliths. Above that are laminated dark shales of the flooding horizon and transgressive highstand, overlain (and often scoured) again by lowstand channel sands. The duration of the Bogevika Member (~3.5-4 Ma) brings the Bashkirian cycles of Bear Island within the Milankovitch frequency band. The unconformity bounded Kobbebukta beach sedimentary outcrop records intermediate-scale (~420 Ka) sea-level fourth-order cycles that are consistent with Middle Pennsylvanian cyclothems in Kansas, USA.


62

Interactive Lithostratigraphic and Biostratigraphic Wallcharts for Offshore Norway a Cooperative Project between NORLEX and Time Scale Creator Felix M. Gradstein1, Øyvind Hammer1, and James Ogg2

1University of Oslo, Norway,[email protected] 3Purdue University, IN, USA The Norwegian Offshore Stratigraphic Lexicon (NORLEX at http://www.nhm2.uio.no/norlex) and the Time Scale Creator Project (https://engineering.purdue.edu/Stratigraphy/tscreator) provide interactive relational stratigraphic databases for offshore Norway. Two practical and current products are

1. Interactive Lithostratigraphic (wall) Chart, and 2. Interactive Biostratigraphic (wall) charts for Mesozoic and Cenozoic.

The charts may be operated on and downloaded from above internet sites. Interactive means that through simple ‘mouse over’ clicking lithostratigraphic formation and member names link directly to their master definition, their age and in which wells they are observed. It also means that when one clicks on a fossil name its basic taxonomy and its picture are shown, and in which offshore well it is observed and how deep. NORLEX provides a relational stratigraphic database for the North Sea, Norwegian Sea, Barents Sea and Svalbard. Mesozoic and Cenozoic members clarify the stratigraphic position and geographic extent of (reservoir) sand bodies. Core photographs, well logs, field outcrops, microfossil occurrences and other vital attributes are all relationally cross-linked. In addition, there are menus for instantly finding updated formation and member tops or microfossil events in all wells, plus a map contouring routine for unit thicknesses and depths. Time Scale Creator (TsC) and its TsC Pro counterpart enable you to explore and create charts of any portion of the geologic time scale from an extensive suite of global and regional events in Earth History. The internal database suite encompasses over 20,000 biologic, geomagnetic, sea-level, stable isotope, and other events. All ages are standardized to Geologic Time Scale 2012, and can be interpolated back to previous time scales, if so desired. The biostratigraphic datapacks for offshore Norway are part of a stratigraphic series that also includes petroleum basins in the Gulf of Mexico, Australia, New Zealand, China, Russia, Alaska and Arctic Canada. The current offshore Norway charts have been compiled with assistance from many geoscientists and organisations. In particular are mentioned Mike Charnock, Harald Brunstad and Els van Wenum (Lundin), Terje Hellem (Idemitsu), Dirk Munsterman (TNO, Utrecht, The Netherlands), Erik Anthonissen (Chevron, USA), Felix Gradstein and Øyvind Hammer (Geology Museum, University of Oslo), Gabi Ogg (Geologic Time Scale Foundation) and James Ogg and students (in particular Rebecca Bobick) (Purdue University, USA).

Interactive Lithostratigraphic and Biostratigraphic Wallcharts for Offshore Norway www.nhm2.uio.no/norlex


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New Insights with Geologic Time Scale 2012 Felix M. Gradstein1, James Ogg2

1University of Oslo, Norway, [email protected] 2Purdue University, IN, USA

Arthur Holmes, the Father of the Geologic Time Scale once wrote: “To place all the scattered pages of earth history in their proper chronological order is by no means an easy task”. Ordering these scattered and torn pages requires a detailed and accurate time scale. Geologic Time Scale 2012 (GTS2012) is more precise and more accurate than GTS2004. Precambrian now has a detailed proposal for chronostratigraphic subdivision instead of an outdated and abstract chronometric one. Of the 100 chronostratigraphic units in the Phanerozoic 63 now have formal definitions. GTS2012 builds on over 265 carefully calibrated radiogenic age dates. Detailed age calibrations now exist between radiometric methods and orbital tuning, making 40Ar-39Ar dates 0.64% older and more accurate; U-Pb dating is much refined. Although radiometric ages can be more precise than zonal or fossil event assignments, the uneven spacing and fluctuating accuracy and precision of both radiometric ages and zonal composite scales demands intricate stratigraphic reasoning, quantitative biostratigraphic methods and clever statistical and mathematical techniques to calculate the geologic time scale. Bases of Paleozoic, Mesozoic and Cenozoic are bracketed by analytically precise ages, respectively 541 ± 0.63, 252.16 ± 0.5 and 66.03 ± 0.05 Ma. High-resolution, direct age-dates now also exist for base-Carboniferous, base-Permian, base-Jurassic, base-Cenomanian and base-Eocene. Relative to GTS2004, 26 of 100 time scale boundaries have changed age, of which 14 have changed more than 4 Ma, and 3 (in Middle to Late Triassic) between 6 and 12 Ma. There is much higher stratigraphic resolution in Late Carboniferous, Jurassic, Cretaceous and Paleogene, and improved integration with stable isotopes stratigraphy. Cenozoic and Cretaceous have a refined magneto-biochronology. An astronomical tuning solution now exists for the whole of the Cenozoic. Ages and durations of Neogene stages derived from the orbital tuning are considered to be accurate to within a precession cycle (~20 kyr) assuming that all cycles are correctly identified. Paleogene dating combines orbital tuning, radiometric and C-sequence splining, hence stage ages uncertainty is larger; it varies between 0.2 and 0.5 myr.


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Nothofagus Sporopollenin δ13C Indicates Decreased Moisture Availability in the Antarctic Eocene Kathryn W. Griener1, David M. Nelson2, Sophie Warny1

1Louisiana State University, Baton Rouge, LA 70803, [email protected]; 2University of Maryland Center for Environmental Science, Frostburg, MD 21532; Previously published palynological data demonstrate that significant changes in vegetation and climate occurred in Antarctica over the past ~50 million years (e.g. Anderson et al., 2011), and that an abrupt change took place at the Eocene-Oligocene Boundary (E-O) on the Antarctic Peninsula (e.g. Warny and Askin, 2011). These changes include decreases in terrestrial palynomorph abundance and diversity as well as dinoflagellate assemblages that reflect colder sea surface temperatures and increased glaciation (Warny and Askin, 2011). Understanding the factors controlling these changes in climate and vegetation is a topic of great interest. One area of remaining uncertainty is how the hydrologic regime varied during Antarctica’s shift from greenhouse to icehouse conditions. For example, estimates of Eocene Antarctic precipitation based on plant leaf margins (e.g. Francis et al., 2008), clay mineralogy (e.g. Christian and Kennett, 1997), and models (Thorn and DeConto 2006) are vastly different. An alternative proxy to estimate moisture is the use of plant δ13C values, which change in response to a plant’s water availability (e.g. Farquhar et al., 1989). We used a moving-wire device interfaced with an isotope-ratio mass spectrometer (Sessions et al., 2005; Nelson et al., 2008) to analyze δ13C values of small quantities of Nothofagus (the genus of Southern beech) sporopollenin. These palynomorphs were obtained from Antarctic Eocene SHALDRIL cores dated at ~35.9 Mya, just prior to the E-O Boundary (Bohaty et al., 2011). To better understand how pollen and sporopollenin relate to water availability, we also analyzed δ13C values of modern Nothofagus pollen and sporopollenin from herbaria and related these results to historical climate data. Our modern data show that carbon isotope discrimination (Δ) of Nothofagus sporopollenin is positively correlated with mean-annual and growing-season precipitation, consistent with prior studies that demonstrate a strong relationship between Δ and water availability in C3 plants (e.g. Nelson, 2012). Our Eocene Nothofagus Δ values progressively decreased through time, implying a decline in moisture availability in the late Eocene. There is a close correlation between Nothofagus palynomorph abundance from the same core (Warny and Askin, 2011) and Δ, indicating that water availability was a large influence on Nothofagus plant production. Quantitative application of our data (e.g. Kohn, 2010) suggests that moisture on the Antarctic Peninsula experienced a significant decline (potentially up to ~90%). We consider changes in sea surface temperatures as well as increased glaciation as possible causes behind these changes in aridity. Detailed Evaluation of Several Vegetation Spikes in the Antarctic Miocene and their Relationship to Rapid Warming and/or Increased Precipitation Kathryn W. Griener1, Sophie Warny1, Rosemary Askin1 1Louisiana State University, Department of Geology & Geophysics, Baton Rouge, LA 70803, [email protected]

Growing concerns about contemporary environmental changes have encouraged scientists across the board to study the potential factors and consequences surrounding climate change. Antarctica’s shift from “greenhouse” to “icehouse” conditions at the Eocene-Oligocene Boundary (~34 Mya; e.g. Anderson et al., 2011; Pagani et al., 2011, Warny and Askin, 2011) provides a uniquely diverse background in which to observe vegetation change under warm and cold regimes as well as the shifts that occurred during key climate transitions. Previous studies of the Antarctic have already contributed to our understanding of Antarctic climate evolution; it is known that the Antarctic climate began to deteriorate rapidly from greenhouse to icehouse conditions just prior to the E-O Boundary (e.g. Barrett, 1996; Warny and Askin, 2011). But was that transition to icehouse conditions permanent throughout the Oligocene and Miocene? Recent palynological analysis of the middle Miocene section of ANDRILL 2A (AND-2A), a 1138.54 meter-long core from the South McMurdo Sound region, indicates that abrupt warm intervals with increased vegetation occurred around the Mid-Miocene Climatic Optimum (Warny et al., 2009) and that the intervals studied indicate that increased plant production coincides with increased precipitation (Feakins et al., 2012). To fully comprehend the fluctuations in vegetation diversity and plant production during the early Miocene, an additional detailed palynological analysis of the older section of this core (below 650 mbsf) is necessary. These early Miocene sections occur prior to significant cooling and presumed expansion of the East Antarctic Ice Sheet at ~14 Ma (Zachos et al., 2001), but sedimentological analyses indicate that the early Miocene was a period of glacial fluctuations in the AND-2A region (Passchier et al., 2011). The sedimentology indicates that ice sheet minima occurred 20.1-19.6 Ma (~1140-937 mbsf) and 19.3-18.7 (~905-786 mbsf) and that these were times of temperate glacial conditions, in contrast to the colder glacial conditions that are thought to have begun ~650 mbsf when sandy, gravelly ice-margin deposition began (Passchier et al., 2011). Additionally, provenance data from AND-2A shows an invasion of McMurdo Sound by the Antarctic ice sheet at ~778 mbsf and ~626 mbsf with a possible short retreat of


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the ice sheet cycle at 699-685 mbsf (Sandroni and Talarico, 2011). A study on the oxygen isotope composition of AND-2A indicates that the region experienced abundance and/or depletion of meltwater preceding ~16 Ma (Marcano et al., 2009). The retreat and expansion of ice and fluctuating meltwater would undoubtedly have had consequences on plant production.

Our project encompasses a detailed palynological analysis of the lower sections of AND-2A, from ~1138-650 mbsf (early Miocene; Acton et al., 2008). A total of 117 samples were selected from this interval based on spacing and lithology. Samples are analyzed for their palynomorph abundance at the CENEX Lab at LSU. Preliminary data from our study indicate an interval of increased palynomorph abundance occurred at ~908 mbsf. This section is dominated by two species of Nothofagus, the genus of Southern beech, and may indicate increased moisture availability (Griener et al., submitted) and warmer temperatures during this time. An additional increase in plant productivity occurs at ~997 mbsf. Both of these intervals coincide with or are proximal to periods of inferred ice sheet minima (Passchier et al., 2011). The completed palynological analysis of this core will allow additional comparison to known climatic factors such as ice sheet expansion/retreat (e.g. Passchier et al., 2011), water availability (Feakins et al., 2012), and global pCO2 levels (e.g. Zachos et al., 2001; Pagani et al., 2011). Further comparison of these data with paleopalynological data can help us to determine the potential driving forces behind vegetation change, underlying factors behind climate evolution, the sensitivity of polar biology and glaciation to climate change, and can help us make predictions about the future of climate change. The Ostracod Genus Cyprideis (Crustacea) and its Implication for Western Amazonia’s Palaeoenvironments (Late Miocene; Solimões Formation; Brazil) Martin Grossa, Werner E. Pillerb, Marco Caporalettib

aDepartment for Geology and Palaeontology, Universalmuseum Joanneum, Weinzöttlstrasse 16, 8045 Graz, Austria; e-mail: [email protected]; telephone: +43-316-8017-9733; fax: +43-316-8017-9671 bInstitute for Earth Sciences, Karl-Franzens-University, Heinrichstrasse 26, 8010 Graz, Austria; e-mail: [email protected], [email protected] Before the Late Miocene onset of the modern, W–E draining Amazon system an enormous wetland – the “Pebas” system – shaped Western Amazonia’s landscape and life for several millions of years. One of the most controversially discussed issues of that ecosystem is the influence of marine incursions. Their existence, chronology, origin as well as their spatial extent is still disputed. Aside from sedimentological and ichnological indications, paleontological evidences (i.e., mangrove pollen, foraminifers, specific molluscs, barnacles) were used to infer transitorily marine influences. In addition, the occurrence of highly endemic, brackish water associated ostracods (particularly Cyprideis) motivated several authors to propose elevated salinities or even marine transgressions. Several outcrops around Eirunepé (SW Amazonas state), which expose the upper part of the Solimões Formation (Late Miocene), were sedimentologically and micropaleontologically investigated (FWF project P12748-N21). Vertically as well as laterally, highly variable fine-grained clastic successions were recorded. Based on the lithofacies assemblages, these sediments represent various subenvironments of a fluvial, possibly anastomosing river system. Lacustrine environments are restricted to local floodplain ponds/lakes. The taxonomic evaluation of the ostracod faunas documents a moderately diverse assemblage (19 species). A wealth of freshwater ostracods (mainly Cytheridella, Penthesilenula) was found co-occurring with taxa (chiefly Cyprideis), which are typically related to marginal marine settings. The observed faunal compositions as well as constantly very light δ18O- and δ13C-values, obtained by analyzing both groups, refer to entirely freshwater conditions, which corroborate the fluvial depositional model for this area. Apparently, Cyprideis has been successfully adapted to pure freshwater settings at least during the Late Miocene fade out of the “Pebas” system. Consequently, the occurrence of Cyprideis and probably of some other “brackish/marine” taxa (Perissocytheridea, Rhadinocytherura) provides no concrete evidence for brackish waters or marine incursions in Western Amazonia during the Miocene. Benthic Foraminiferal Assemblages Reveal the History of the Burdigalian Seaway Patrick Grunert1, Werner E. Piller1, Mathias Harzhauser2 1 Institute for Earth Sciences, University of Graz, Heinrichstraße 26, A-8010 Graz, Austria; [email protected] 2 Geological-Paleontological Department, Natural History Museum Vienna, Burgring 7, A-1014 Vienna, Austria The opening and closure of seaways have immanent paleoclimatic, paleoceanographic and paleobiogeographic consequences as they determine the exchange of water masses between marine basins. During the Oligocene to Miocene severe alterations of marine gateway configuration (e.g., Tethyan Seaway, Pre-Gibraltar Seaway, Burdigalian Seaway; Harzhauser and Piller, 2007) shaped the evolution of the Mediterranean-Paratethys region.


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From early to middle Burdigalian (c. 20.4-17.5 Myrs) the Burdigalian Seaway connected the western Mediterranean Sea and Atlantic Ocean with the Central Paratethys Sea via the North Alpine Foreland Basin (NAFB). Its evolution resulted in profound changes of paleoceanography and paleogeography, and initiated a wave of macro- and microfaunal immigration from the Atlantic and Mediterranean into the Central Paratethys that had a severe impact on marine ecosystems. A detailed Early Miocene proxy record that integrates seismic images, microfossil assemblages and geochemical analyses has been recently established for the trough of the Puchkirchen Basin as part of the NAFB (Grunert et al., 2012, 2013). Herein, we exemplary show the reconstruction of the dynamic early to middle Burdigalian paleoenvironment based on the quantitative evaluation of benthic foraminiferal assemblages from drill-sites and outcrops. Based on the data, four major phases in the development of the Puchkirchen Basin are distinguished, and new bio- and sequence stratigraphic constraints allow to discuss the results in the context of the evolution of the Burdigalian Seaway: 1. The global sea-level rise at the beginning of the Burdigalian initiated a marine transgression in the NAFB. In the Puchkirchen Basin, a long-lived basin-axial channel system was reactivated resulting in turbiditic and mass-flow deposition. The unstable upper bathyal environment is reflected in a low diverse autochthonous benthic foraminiferal fauna mainly composed of Bathysiphon filiformis. 2. The perpetuating transgression flooded large shelf areas and established the Burdigalian Seaway. As a result the channel belt in the Puchkirchen Basin was cut off from its sediment sources and shut down. Subsequently, sedimentation was controlled by episodic turbidite deposition originating from the southern basin margin, and large NE prograding delta fans into the basin. High sedimentation rates and strong input from the hinterland led to the development of diverse foraminiferal faunas that are largely composed of agglutinated species. The encountered astrorhizids, ammodiscids and textualriids reflect communities adapted to high input of organic matter and suboxic bottom-waters. Assemblages dominated by Bathysiphon filiformis occur in phases of turbidite deposition. 3. At c. 19 Ma the Burdigalian Seaway became a vast shelf sea when increasing sedimentation rates led to the upfill of the deep-marine Puchkirchen Basin. At the same time marine sedimentation reached its maximum extent in the NAFB. Characteristic hyaline shelf faunas composed of species of Lenticulina, Amphicoryna, Melonis, Cibcidoides and Ammonia developed along the inner-outer neritic shelf environments. 4. The beginning of a regression at c. 18 Ma heralded the closure of the Burdigalian Seaway. Biofacies distribution shows a prograding tide-influenced shelf and widespread shallow water environments largely dominated by Ammonia, Elphidium and Cibicidoides developed. The closure of the Burdigalian Seaway initiated a major reorganization of paleogeography resulting in the final retreated of the Central Paratethys towards the east. Grunert, P., Hinsch, R., Sachenhofer, R., Ćorić, S., Harzhauser, M., Piller, W.E., Sperl, H. (2013). Early Burdigalian infill of the

Puchkirchen Trough (North Alpine Foreland Basin, Central Paratethys): facies development and sequence stratigraphy. Marine and Petroleum Geology 39, 164-186.

Grunert, P., Soliman, A., Ćorić, S., Roetzel, R., Harzhauser, M., Piller, W.E. (2012). Facies development along the tide-influenced shelf of the Burdigalian Seaway: an example from the Ottnangian stratotype (Early Miocene, middle Burdigalian). Marine Micropaleontology 84-85, 14-36.

Harzhauser, M., Piller, W. E. (2007). Benchmark data of a changing sea. Palaeogeography, Palaeobiogeography and Events in the Central Paratethys during the Miocene. Palaeogeography, Palaeoclimatology, Palaeoecology 253, 8–31.

Time Resolution and Trace Detection When a Distinction Between Vertical Deposition and Lateral Transport is Not Possible in the Stratigraphic Record Ali T. Haidar Department of Geology, American University of Beirut, Riad El-Solh, Beirut 1107 2020, Lebanon [email protected] Events occurring in the depositional environment (E) could be deposited either vertically (V) or by lateral transport (L). E is a vector space with dimension 4: XE, YE, ZE, and TE. The stratigraphic record (S) related to a locality (1, 2, …, n) is a vector space with dimension 3: XS, YS, and ZS (stratigraphic distance), with the dimension TS found along the same direction of that of (embedded within) ZS. ZSV is related to TE and (by some fluid removal, to the compression of) ZE. When L occurs from point location 1 to point location 2 (L1-2), the coordinates along XS2 and YS2 related to this event represent XE1 and YE1. A lateral transport adds therefore a new ZS2 (ZSL1-2) within the old ZS2 (ZSV2). This can be thought of as an expansion of single points along the ZSV2 into discrete distances made of ZSL1-2.


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In terms of representation of TE by TS, ZSL1-2 increases the time resolution within ZS2, and decreases it (e.g., by having an unconformity) in ZS1. If the record related to the time by vertical deposition is “complete”, the time necessary for L1-2 as represented in S2 (TSL1-2) constitutes a time “duplicate” (i.e., a repetition of the record of a discrete interval of time), rather than an increase in time resolution. This would be true only if we consider SL1-2 as representing TE rather than TSL1-2. Otherwise, instead of time duplication (repetition of representation of the same time), only trace duplication (repetition of the representation of traces that have occurred only once in E) would be present. The time resolution related to this time interval is not sufficient to detect whether this trace has originally occurred more than once in E or the multiple occurrences of the trace in S are simply due to L1-2. In both cases (whether we consider SL1-2 representing TE or TSL1-2), it would be theoretically impossible to reconstruct the environmental history of E based on traces in S (i.e., not possible to determine whether the observation of the same trace signatures at different levels in S are related to only one or to many occurrences in E). In other words, any work of high resolution stratigraphy trying to reconstruct trace occurrences of E by sampling together SV and SL would incur into this duplication. These traces would come from E to S1 by V, and then to S2 twice (by V and by SL1-2) forming 2 separate vector subspaces (2 separate layers) in S out of a single event in E. The trace occurrence by SL1-2 would necessarily overlap that by V (and not vice versa) if the speed of V in S1 is similar to that in S2 (assuming similarity in S depth and in trace sinking rate, etc.). The lowest occurrence of a trace in any S is therefore to be sampled when trying to sample the V record only. In case the V record of the trace was eroded, then the lowest trace would be due to L1-2, and this has to be sampled instead in order to better approximate the position of the first occurrence, because neither time nor trace duplications will occur if only the lowest occurrence was sampled. In other words, the stratigraphic record, under these conditions of impossibility of detecting the repetition of similar trace signatures of E when high time resolution is required, has therefore the potential of detecting the presence of the traces that have occurred in E at least once, but not the frequency of their occurrence. Scalars of the vector subspace related to L1-2 are elements of a finite field having only the two elements 0 (absence of SL1-2) and 1 (presence of SL1-2), where 1 + 1 = 1 (more than one SL1-2 occurrence is equivalent to only one occurrence). When the scalars are from the field of two elements, each coordinate is 0 (bedding plane) or 1 (within the layer), so each vector (along the stratigraphic distance) can be viewed as a particular sequence of 0s and 1s. This makes the “signal processing” of laterally transported sediments (containing traces or fossils) similar to “digital processing”. Measuring Growth Speed and Chamber Construction in Two Selected Foraminifera with Micro-CT Christian Haller and Martin Langer Rheinische Friedrich-Wilhelms-Universität, Bonn, GERMANY, Steinmann-Institut für Geologie, Mineralogie und Paläontologie, [email protected] High resolution X-Ray Computer Tomography (Micro-CT) is a method for generating non-invasive insight into opaque objects. In contrast to standard 2D tomography known from medical applications, Micro-CT provides digital images 360 degrees around a specimen and computes the images into three-dimensional objects. Microtomography plays an increasingly important role in engineering processes and various natural science applications (including the study of biological and paleontological material). High-resolution CT shows that microfossils can be visualized in exceptional detail. Current generation scanning devices reach resolutions of over 1 µm, which is enough for detailed images of minute objects including fossilized remains of foraminifera. We applied the Micro-CT model “GE v|tome|x s“, housed at the Steinmann-Institute Bonn (Germany), on foraminiferal tests to explore the capabilities for quantitative test analysis (test volume, growth rates, examination of internal test features). For maximum precision and resolution, individual tests were scanned separately. For this study, five specimens were selected from recent sediment samples collected by Scuba-diving around the tropical island of Pemba (Tanzania). The specimens selected belong to the agglutinated genus Siphoniferoides cf. S. balearicus (COLOM) and one specimen belongs to the genus Lachlanella corrugata (COLLINS), a calcareous miliolid. From the 3D models, individual volumes of the chambers and complete tests were computed and growth patterns analyzed. Siphoniferoides cf. S. balearicus revealed two different growth stages with separate volume growth rates: an early stage with triserial chamber arrangement and exponential volume increase, and a biserial stage with a slower linear volume increase. L. corrugata displays an exponential volume increase throughout its lifespan. Comparative analysis of miliolid and agglutinated species shows fundamentally different growth and life strategies. In conclusion, Micro-CT allows a rapid, non-destructive, cost-effective and detailed analysis of foraminiferal specimens. Illustration of 3D models shows that studies of quantitative biometry in foraminiferology paves the way for new avenues of research.


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Figure 1: 3D models of Siphoniferoides cf. S. balearicus. (A) external view of a scanned Micro CT specimen, (B) horizontally clipped specimen, (C) horizontally clipped specimen with colored chamber lumina.

Planktonic Foraminiferal Biostratigraphy and Paleoecology of the Miocene Sequence in the Area Between Wadi Gharandal and Bir Haleifiya, Gulf of Suez Region, Egypt Mostafa M. Hamad Cairo University, Faculty of Science, Geology Department, Egypt. [email protected] An integrated biostratigraphical analysis based on the planktonic and larger foraminifera from three surface sections in the area between wadi Gharandal and Bir Haleifiya, Gulf of Suez region, Egypt, namely wadi gharandal, gebel zeita and bir halefiya sections, provides a well-defined zonal scheme of the Miocene successions in the study area. Lithostrtigraphically, the Miocene sequence could be differentiated into four rock units representing shallow and deep marine facies. These are from base to top as follows: Nukhul, Rudeis, Kareem formations (Gharandal Group) and Belayim formation (Ras Malaab Group). The examination of the studied samples has led to the identification of forty-four planktonic foraminiferal species and subspecis belonging to twelve genera. The preserved planktonic foraminifers through the studied sections ranges from good to moderately well diversified enabled biostratigraphic zonation of the Miocene sequence. On the basis of the vertical stratigraphic distribution of the planktonic foraminiferal species, the studied sections could be subdivided into six planktonic foraminiferal biozones following the Mediterranean (MMi) zonal schemes, from base to top as follows: (1) Globigerinoides primordius Zone (MMi1) (Early Miocene, Aquitanian), (2) Globigerionides altiaperturus - Catapsydrax dissimilis Zone (MMi 2b), (3) Globigerinlides tribobus Zone (MMi 3) (Early Miocene, Burdigalian) (4) Prearobulina glomerosa s.l. Zone(MMi 4), (5) Orbulina suturalis - Globoratalia fohsi peripheroronda Zone (MMi 5), (Middle Miocene, Langhian), and (6) Globoratalia siakensis Zone (MMi 6), of Middle Miocene (Serravallian) age. The Lower/Middle Miocene boundary is defined by the first occurrence of Praeorbulina glomerosa and is discussed within the text. Two larger foraminiferal zones were recognized in the studied successions (Wadi Gharandal and Bir Halefiya sections), from base to top, SB 24 Zone in the Aquitanian and SB 25 Zone in the Burdigalian, according to the European shallow benthic foraminiferal zonation (SBZ). By integrating the established foraminiferal zonal schemes, the stratigraphical ranges of some larger foraminifera with planktonic foraminiferal zones have been calibrated. According to the integrated zonation, the Miolepidocyclina burdigalensis, Miogypsina intermedia and Borelis curdica first occur in the MMi 1 and MMi 2b zones, whereas Nephrolepidina spp. last occur within the same subzone (MMi 2b). Correlation of the identified larger and planktonic foraminiferal biozones indicates strong similarities with that of Mediterranean affinities. Di Stefano A., Foresi L.M., Lirer F., Iaccarino S.M., Turco E., Amore F.O., Mazzei R., Morabito S., Salvatorini G. & Aziz H.A. (2008).

Calcareous plankton high resolution biomagnetostratigraphy for the Langhian of the Mediterranean Area. Rivista Italiana di Paleontologia e Stratigrafia, 114 (1): 51- 76.

Iaccarino S.M., Premoli Silva I., Biolzi M., Foresi L.M., Lirer F., Turco E. & Petrizzo M.R. (2007). Practical manual of Neogene Planktonic Foraminifera. International School on Planktonic Foraminifera (6th course). 141 pp. Biolzi M. et al. (eds.), Perugia.

Özcan, E. & Less, G. 2009. First record of the co-occurrences of Western Tethyan and Indo-Pacifi c larger foraminifera in the Burdigalian of the Mediterranean province. Journal of Foraminiferal Research 39, 23–39.

Sprovieri R., Bonomo S., Caruso A., Di Stefano A., Di Stefano E., Foresi L.M., Iaccarino S.M., Lirer F., Mazzei R. & Salvatorini G. 2002b: An integrated calcareous plankton biostratigraphical scheme and bio-chronology for the Mediterranean Middle Miocene. In: Iaccarino S. (Ed.): Integrated stratigraphy and paleoceanography of the Mediterranean Middle Miocene. Riv. Ital. Paleont. Stratigr. 108, 337—353.

triserial

biserial

250 µm

A B C


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The Holocene Separation of Jersey from Mainland Europe Malcolm B. Hart1, Paul Chambers2, Graham Evans2, Ralph Nichols2, & John E. Whittaker3

1School of Geography, Earth & Environmental Sciences, Plymouth University, Drake Circus, Plymouth PL4 8AA, U.K. 2Société Jersiaise, 7 Pier Road, St Helier, Jersey JE2 4XW, U.K. 3Natural History Museum, Cromwell Road, London SW7 5BD, U.K. The island of Jersey receives most of its electrical power from France by way of two submarine cables. These are now nearing a time when replacement must be considered and a new cable is now planned. More than fifty marine boreholes have been drilled into the seabed between France and the east coast of Jersey and these are being used to plan the route of the new cable by consultants. Aside from rare, mainly terrestrial, Pleistocene and Holocene sediments, Jersey is formed of Precambrian to Devonian ‘basement’ and the off-shore area, at low tide, is dominated by E–W trending rock platforms including, to the north, Les Ecréhou and, to the south, Les Minquiers and the Isles Chausey. The Baie du Mont-St-Michel, in which Jersey sits, is macrotidal with an exceptionally large tidal range and the planned cable must be buried within the very limited sediment cover. The sediment succession of the post–Last Glacial Maximum is only present between Grouville, on the east coast of Jersey, and the immediately adjacent coastline of France. The cores, which are now stored on Jersey, provide a complete record of this Holocene sedimentary record and core OVC-18 is being used as a reference because it contains a near-complete record of the transition from woodland, with peats and plant beds, to inter-tidal mud flats and, eventually, marine sediments with abundant marine fossils and highly significant occurrences of the calcareous alga Phymatolithon calcareum (known locally as maerl). This core, therefore, contains a record of Holocene sea level rise through to the invasion of the slipper limpet Crepidula in 1962. Many of the samples contain well-preserved assemblages of foraminifera and ostracods that allow the reconstruction of a range of sub-environments through to fully marine. Below the terrestrial sediments in core OVC-18 is a thickness of carbonate-rich, marine sands that may be of Eocene age or derived from pre-existing Eocene sediments. Test Deformation in Foraminifera: Variable Impacts Caused by Metal Contamination and/or Lowered Ph in Estuarine and Marine Environments Malcolm B. Hart and Christopher W. Smart School of Geography, Earth & Environmental Sciences, Plymouth University, Drake Circus, Plymouth PL4 8AA, United Kingdom [email protected] Test malformation or deformity in foraminifera is exceptionally rare in geological samples but is more frequently recorded in modern (often estuarine) samples from less than optimal environments. On 16th January 1992 an accidental release of acidic water from a flooded mine into the Carnon River in Cornwall (UK), caused extensive contamination of Restronguet Creek (estuarine area) and the Fal Roads (marine area). The water entering Restronguet creek was rich in metals (Cu, Zn, Sn, Fe, etc.) and with a pH of 3.2. The short-term impact was a loss of all benthic foraminifera for a period of almost two years. Mitigation measures to normalize the pH of the water entering Restronguet Creek was in place by 1994. The living benthic foraminifera (mainly Ammonia aberdoveyensis, Elphidium williamsoni and Haynesina germanica) were re-established by 1993, but with relatively high (<22.5% of the standing crop) levels of coiling deformation, malformed and additional chambers. Despite some improvement, deformed tests are still being recorded (0.06%–15.4% of the standing crop) as the estuarine muds and silts remain contaminated by metals. Some of this contamination was delivered by the 1992 flood, but much of it dates from the mid-19th century mining activity. The pH of the water entering the estuarine system is, however, normal. In the Mediterranean Sea around Ischia (pH 8.17 to 6.70) and in the Wagner basin (Gulf of California), where a sea floor pH of 7.40 to 7.80 is recorded, there are living (= stained by rose Bengal) assemblages of foraminifera but almost no record of test deformation. In both areas there are post-mortem dissolution effects (surface pitting and fragmentation) and this is a problem for those assessing the impact of acidification in the geological record. These studies indicate that metal pollution will cause on-going evidence of deformed tests while a drop in pH restricts the species content of the living assemblage but appears not to result in many (if any) deformed tests. In laboratory cultures, where foraminifera are living in reduced pH conditions, the recorded levels of test deformation may be more related to the culture environment than the effects of the lowered pH and results may have to be treated with caution. Foraminifera studied in naturally lowered pH environments do not appear to record the same levels of test deformation.


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From Water to Sediment: Preservation Potential of Organic-Walled Algae in Modern Missouri Lakes R.D. Haselwander and F.E. Oboh-Ikuenobe Missouri University of Science and Technology, Department of Geological Sciences and Engineering, Rolla, Missouri, 65409, USA, [email protected] Paleolimnological studies have long used particular forms of algae, predominantly diatoms, as proxies for important information about past conditions, such as trophic status, lake level, and anthropogenic influence. Recent paleopalynological studies have used organic-walled algae, such as desmids and the colonial green alga Botryococcus to derive similar information (e.g., Chmura et al., 2006; Medeanic and Silva, 2010; Worobiec, 2011). In order to create meaningful interpretations from palynological data, it is essential to understand the preservation potential of the organic material used for interpretation. This will be determined by examining lake water and the top few cm’s of sediment samples to evaluate the presence of algae. The algal assemblages in the water and sediment will be compared to each other in order to understand their preservation potential The first part of this study focused on a qualitative survey of planktonic algae in White Oak Pond, which is a natural sinkhole lake near Lebanon, Missouri, USA. Water samples were obtained by filtering lake water through a phytoplankton net pulled behind a canoe, and compared with algal remains in the top few cm’s of sediments sampled from a Livingstone style corer. The sediment was processed using standard palynological methods (Traverse, 2007) and strew mounted on glass slides. Water and sediment samples were examined using transmitted light microscopy in order to identify the algae and assess their relative abundances. A moderately diverse and highly abundant algal assemblage was identified in the water samples. The lake water assemblage (Table 1) comprises planktonic algae, including single-celled forms ranging from diatoms and radiolarians to Chrysophytes such as Ochromonas and Synurophytes (e.g. Mallomonas). Ceratium, the most common freshwater dinoflagellate (Prescott 1964), was also present. Botryococcus and Planktolyngbya?, a filamentous alga of uncertain affinity (Wehr and Sheath, 2003), were also identified in the water samples. Ochromonas was the most abundant algal type, while Planktolyngbya?, Ceratium and Botryococcus were also common in the assemblage. A comparable, though less diverse assemblage, was found in the sediment sample; however, Botryococcus dominates this assemblage. Dinoflagellate cysts and filamentous algae were rare, but important components of the sediment samples. Ceratium appears to be more abundant in the lake water in comparison to dinoflagellate cysts in the sediment. It is unclear if the filamentous algae in the sediment are related to the Planktolyngbya? in the water samples because chloroplasts and other important markers for identification are often absent. Zygospores of Spirogyra were present only in the sediment since it is a benthic alga (Wehr and Sheath, 2003). The second part of this study is investigating two man-made freshwater lakes in nearby Rolla, Missouri. One of these lakes is located in a residential area, while the second lake is located in a conservation area. A set amount of lake water (4.5 L) was filtered through a phytoplankton net, and sediment samples followed the same process outlined above. Preliminary results indicate that Ochromonas dominates the algal population in both lakes, which contains rare diatoms and Botryococcus. There is higher diversity in the conservation lake where taxa such as Dinobryon and Ankistrodesmus are a rare presence. The ultimate goal is to identify which algal types are likely to be fossilized.

Table 1: Presence/Absence Data for White Oak Pond algae.

Chmura, G.L., Stone, P.A., and Ross, M.S., 2006. Non-pollen microfossils in Everglade sediments. Review of Paleobotany and

Palynology, v. 141, p. 103 – 119. Medeanic , S., and Silva, M.B., 2010. Indicative value of non-pollen palynomorphs (NPPs) and palynofacies for

paleoreconstructions: Holocene Peat, Brazil. International Journal of Coal Geology, v. 84, p. 248 – 257. Montoya, E., Rull, V., and Vegas-Vilarrubia, T., 2010. Non-pollen palynomorph studies in the Neotropics: the case of Venezuela.

Review of Paleobotany and Palynology, v. 186. p. 102 – 130. Prescott, G.W., 1964. How to Know the Freshwater Algae. William C. Brown, Co. Publishers, Dubuque, IA, 272 p.

Sediment WaterSpirogyra * -‐Planktolyngbya? * +

Colonial Botryococcus ++ +Ochromonas -‐ ++Dinoflagellate * +Radiolarian sp. -‐ *Diatom sp. -‐ *Mallomonas -‐ *

Presence

Filamentous

Single Cell

Algae

Key:++ v. common+ common* rare-‐ absent


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Traverse, A., 2007. Paleopalynology, 2nd Edition. Springer, Dordrect, Netherlands, 813 p. Wehr, J.D., and Sheath, R.G., 2003. Freshwater Algae of North America. Academic Press, New York, 918 p. Worobiec, E., 2011. Middle Miocene aquatic and wetland vegetation of the paleosinkhole at Tarnow Opolski, SW Poland. Journal

of Paleolimnology, v. 45, p. 311 – 322. Reconstructing Holocene Salinity Changes in the Aegean Sea Using Morphological Variations of Emiliania Huxleyi-Coccoliths J. O. Herrle(1,2), C. Gebühr(1,2), J. Bollmann(3), A. Giesenberg(1,2), P. Kranzdorf(1,2) (1)Institute of Geosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; email: [email protected] (2)Biodiversity and Climate Research Centre (BIK-F), 60325 Frankfurt am Main, Germany, (3)Department of Geology, Earth Sciences Centre, University of Toronto, 22 Russell Street, Toronto, Ontario, M5S 3B1, Canada The Aegean Sea is a key area for our understanding of the impact of changes in the hydrological cycle on ocean circulation in the Mediterranean Sea. The Aegean Sea appears to be very sensitive to climate changes in Europe because of its small volume and the position between high- and low-latitude climate regimes. Therefore, it is assumed to record environmental change, especially changes in sea surface water salinity (SSS) without a significant time lag with respect to the forcing process (Rohling et al., 2002). However, up to date, SSS cannot be easily reconstructed from geological archives because several assumptions need to be made that lead to a significant error of the salinity estimates (e.g. Rohling, 2000). Here, we present the first high resolution SSS reconstruction from a Holocene sediment core based on a recently developed transfer function using the morphological variation of Emiliania huxleyi coccoliths (Bollmann & Herrle 2007, Bollmann et al., 2009). The core is located in the northern Aegean Sea (eastern Mediterranean Basin) and covers the time period 3 –11ka ago. Sea surface water salinity in the Aegean Sea has varied in concert with temperature oscillations as recorded in Greenland ice cores (iGISP2 ice core δ18O record) with a periodicity of about 900 years (Schulz & Paull, 2002). Four major SSS events can be identified at about 3.9, 4.7, 6.4, 7.4, and 8.2 ka in the northern Aegean Sea that correlate with increases in GISP2 δ18O (Schulz & Paull, 2002) as well as decreasing percentages of tree pollen studied at the same core expect for 3.9 ka (Kotthoff et al., 2008). The most prominent salinity increase occurred during the short-lived 8.2 kyr cold event (e.g., Rohling & Pälike, 2005), which was most likely triggered by a melt-water related perturbation of the Atlantic Meridional Overturning and associated decrease of ocean heat transport to the North Atlantic. We suggest that the salinity fluctuations in the northern Aegean Sea are related to large-scale changes in the Northern Hemisphere climate system with effects similar to the decadal North Atlantic Oscillation. During times of a negative NAO the amount of precipitation and river runoff increases in the northern Aegean Sea (more fresh water input -> low salinity) whereas the amount of precipitation and river runoff decreases during a positive NAO (less fresh water input -> low salinity) (e.g., Tsimplis & Baker, 2000). The NAO-like SSS fluctuations may also have caused changes in the deep water formation in the northern Aegean Sea and thus affect the oxygenation of bottom water and the evolution of Holocene benthic ecosystem. Bollmann, J., Herrle, J.O., 2007. Morphological variation of Emiliania huxleyi and sea surface salinity. EPSL 255, 273–288. Bollmann, J., Herrle, J.O., Cortez, M., Fielding, S.R., 2009. The effect of sea water salinity on the morphology of Emiliania huxleyi in

plankton and sediment samples. EPSL 284, 320-328. Henderson, G., 2002. New oceanic proxies for paleoclimate. EPSL 203, 1–13. Kotthoff, U., Pross, J., Müller, U.C., Peyron, O., Schmiedl, G., Schulz, H. and Bordon, A. 2008: Climate dynamics in the borderlands

of the Aegean Sea during formation of Sapropel S1 deduced from a marine pollen record. Quaternary Science Reviews 27, 832–45.

Rohling, E.J., 2000. Paleosalinity: confidence limits and future applications. Mar. Geol. 163, 1–11. Rohling, E.J., Mayewski, P.A., Hayes, A., Abu-Zied, R.H., Casford, J.S.L., 2002. Holocene atmosphere–ocean interactions: records

from Greenland and the Aegean Sea. Climate Dynamics 18, 587–593. Rohling, E.J., Palike, H., 2005. Centennial-scale climate cooling with a sudden cold event around 8,200 years ago. Nature 434,

975–979. Schulz, M., & Paul, A., 2002. Holocene Climate Variability on Centennial-to-Millennial Time Scales:1. Climate Records from the

North-Atlantic Realm in Wefer et al. (eds.) Climate Development and History of the North Atlantic Realm. Springer-Verlag Berlin Heidelberg, pp 41-54

Tsimplis M.N., Baker T.F., 2000. Sea level drop in the Mediterranean Sea: an indicator of deep water salinity and temperature changes? Geophys. Res. Let. 27, 1731–1734.


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Age of Siliciclastic-Dominated Fars Group of the Batina Coast, North Oman, Inferred from Bioclastic-Bearing Carbonate Unit O. Salad Hersi1, I.A. Abbasi2, S. Ahmed3, and T. Al-Raisi4 [email protected],; 1Dept. of Geology, University of Regina, Regina, SK, Canada, 2Dept. of Earth Sciences, Soultan Qaboos University, Muscat, Oman, 3Dept of Geology, University of Peshawar, Peshawar, Pakistan, 4Petroleum Development of Oman, Muscat, Oman. Introduction: The Batina Coast of the Gulf of Oman runs along the eastern flank of North Oman Hajar Mountains. The main uplifting phase of the mountain range was related to late Alpine deformation (Hanna, 1995). This was followed by intensive erosion of the elevated land and deposition of siliciclastic-dominated strata, (Fars Group) on the western and eastern flanks of the mountain range. The plain of the Batina Coast preserves a thick succession of these syn- to post-uplifting sediments (Fars Group) but it is covered by Quaternary deposits. Road-cuts within the campus of Sultan Qaboos University (SQU, Fig. 1) expose an almost complete succession of the Fars Group. It is the objective of this project to decipher the lithostratigraphic arrangement and relative ages of the different lithologic units that constitute the group based on foraminiferal content of a thin carbonate tongue that intervene the clastic units (Fig. 2). Integration of the lithostratigraphic stacking nature along with the inferred ages of the lithologic units allows correlation with coeval units in the region and interpretation of the tectono-sedimentary evolution of the Batina coast. Lithostratigraphy of the Fars Group: The Fars Group of the study area includes three lithologic units of lower siliciclastics (Unit I), middle carbonates (Unit II) and upper siliciclastics (Unit III). These strata are tilted and surmounted by Quaternary deposits with angular unconformity. Unit I is the lowest stratigrpahic unit and its lower contact with the MAM Reefs (Asmari Fm.) is concealed under Quaternary deposits and buildings of the southern side of SQU. The exposed section of Unit I is about 46 meters thick and characterized by cycles of fining-upward succession of cobble-size, grey conglomerates through green to red lithic arenite to yellowish brown mudrock facies. Sedimentary structures in the unit include cross bedding, imbricated grains and scour surfaces. Remains of plant debris and root or branch casts are also present. The unit is interpreted as fluvial deposits. Unit II is a carbonate unit which lies unconformably over Unit I with a basal transgressive, conglomeratic lag deposit. The unit is about 15 meters thick, and dominated by massive, coral-built framestone. Other fossils include red algae, bivalves, gastropods, echinoids, calcareous warm tubes and foraminifera. These bioclasts form pockets” of cross laminated, packstone to grainstone lithofacies within the reef body. The unit becomes muddier upward, its uppermost part is partially dolomitized and surmounted by a karstic surface followed by conglomerates of Unit III. Unit II accumulated in a shallow, normal marine setting. Unit III forms the Barzaman Formation which is recognized on the western side of the Omani Mountains (Maizels, 1988)). It is about 85 m thick and divisible into subunit III-A and transitionally overlying subunit III-B (Fig. 2). The two subunits are equivalent to units C and D of Salad Hersi et al (2012). Unit III-A consists of brownish cobble- to pebble-size conglomerates that are relatively well-cemented. It is highly channelized with common graded beds, lateral facies changes (conglomerate to sandstone) and imbricated clasts. Clasts are dominated by weathered mafic rocks but there are also boulder-size coral heads eroded from Unit II. Thin, laterally discontinuous layers of light brown mudrocks with orange-weathering root casts and leaf imprints occur in different stratigrahic horizons. Subunit III-B is characterized by poorly-sorted, massive, grain- to matrix-supported, highly carbonated conglomerates. This facies is identical to the Barzamanite facies of Maizels (1988). Unit III is interpreted as alluvial fan to braided river deposit with subordinate interchannel flood plains (III-A) to fan delta in a lacustrine deposits (III-B). Deposition of Barzaman Formation (Unit III) was followed by tectonic disturbance which caused uplifting and northward tilting (up to 20o) of the strata. Quaternary gravel and sand fill deeply cut channels and blankets over Barzaman Fm. and older strata. Age of the Fars Group: The fossil content of the carbonate body (Unit II) contain a significant number of foraminifera, such as, fairly preserved Rotalids and fragmented or altered Alveolinids, Numulitids and Lepidocyclinids. The latter are considered to be reworked from Eocene to Oligocene strata. One age-diagnostic species of middle Miocene Lepidocyclina (Nephrolepidina) ferreroi Provale, 1909, was recognized. Thus, the middle carbonate unit is Middle Miocene (Langhian to ?Serravallian) in age. This conclusion suggests a lower Miocene age the lower siliciclastic unit of the Lower Fars Group (Unit I) and upper Miocene to possibly Pliocene age for the Barzaman Formation (Unit III). Discussion: The lithostratigraphic arrangement of the Fars Group of the study area reflects the tectono-eustatic evolution of the Batina Coast. Although the carbonates of the MAM Reefs contain siliciclastic beds and thus an exposed source area in the hinterland mountains, the lower siliciclastic unit of the Fars Group (Unit I) suggests a significant late Oligocene – early Miocene elevated source area. This was followed by a relaxation period and relative sea level rise that allowed accumulation of the carbonate beds of Unit II in Middle Miocene. The most intensive uplifting of the Oman Mountains took place at the early Late Miocene heralding deposition of the Barzaman Formation on either side of the mountain range. The studied succession shows close lithostratigraphic correlation with coeval strata of the nearby Arabian region underscoring the regional extent of the tectono-eustatic changes and resulting sedimentary record.


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Fig. 1: A) Location of the Batina Coast and the study area. Satellite image of Sultan Qaboos University (SQU) and studied sections are shown in B. Fig. 2 (right) Stratigraphic chart of the Oligocene to Quaternary strata of the Batina Coast. See text for descriptions of the different lithologic units. Hanna, S., (1995) Field Guide To The Geology Of Oman. The Historical Association of Oman, pp. 143 Maizels, J., 1988. Palaeochannels: Plio-Pleistocene raised channel systems of the western Sharqiyah. In: Dutton, R.W. (Ed.), The

Scientific Results of the Royal Geographical Society’s Oman Wahiba Project 1985–1987. Journal of Oman studies Special Report l.

Salad Hersi, O., Abbasi, I.A., Ahmed, S. and Al-Raisi, T. (2012) Geology of the Sultan Qaboos University campus, Wilayat Seeb, Muscat, Oman. International conference on the geology of the Arabian Plate and the Oman Mountains. Muscat, Oman, pp. 219-220.

Revising Middle Eocene Planktonic Foraminiferal Bioevents, Integrating Bio-Magneto-Chronology Shari L. Hilding-Kronforst, Geology & Geophysics, Texas A&M University, Mail Stop 3115 TAMU, College Station, TX 77843-3115, [email protected] Bridget S. Wade, School of Earth & Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, United Kingdom Planktonic foraminiferal biostratigraphy provides an important tool for constraining the timing of dynamic changes throughout the middle Eocene. Recently the biochronology of the early middle Eocene has undergone significant changes, which have consequently impacted the duration of the planktonic foraminiferal biochrons. We examine planktonic foraminiferal assemblages from Ocean Drilling Project (ODP) Leg 171B, Site 1051, Blake Nose in the western North Atlantic Ocean. Planktonic foraminifera are abundant, with diverse assemblages. Quantitative biostratigraphy was conducted on planktonic foraminifera from 119 to 369 meters below sea floor. This interval corresponds to magnetochrons C18r to C21n. All planktonic foraminifera are well preserved (although recrystallized), and assemblages are diverse with common Acarinina, Globigerinatheka, Morozovella, Subbotina, and Turborotalia with Globigerinatheka, Hantkenina Morozovella and Morozovelloides evolving through this interval. Our quantitative biostratigraphy reveals highest and lowest occurrences of key marker taxa including Turborotalia frontosa, Guembelitrioides nuttalli, Morozovella aragonensis, and Globigerinatheka kugleri. Other distinctive bioevents are also well constrained and recalibrated to the Geomagnetic Polarity Time Scale including Morozovelloides lehneri and several acarininid species. This study allows for significant revision and recalibration of Eocene planktonic foraminifera Zones E7 through Zone E11. The Role of Foraminiferal Biofacies in Developing a Geologically Integrated Stratigraphic Framework for the North Coast Marine Area, Trinidad & Tobago Nicholas Holmes1, Patel Balwant2, Nadine Bedayse2, Mike Curtis3, Roger Kimber3, Tim Needham4, and Andrew Thurlow1 1, Ichron Limited, UK, [email protected] 2, Centrica Energy, Port of Spain, Trinidad


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3, Centrica Energy, UK 4, Needham geosciences, UK Key reservoir intervals from the North Coast Marine Area, north of Trinidad & Tobago, occur predominantly within a shelf setting, and as a consequence, facies variation across the NCMA is considerable. This impacts the biostratigraphy, reducing the presence of chronostratigraphically useful microfossils, as well as resulting in considerable microfossil assemblage variation. In order to provide a biostratigraphic correlative framework at the required scale, to calibrate and constrain seismic and sedimentological data, there is a requirement to interpret and distinguish between regional and field-specific variation in foraminiferal assemblage character. The interval under study predominantly comprises the Late Miocene to Pleistocene, with key reservoir horizons located within the uppermost Late Miocene and Early Pliocene. Due to the predominance of a shelfal setting within much of the Early Pliocene, chronostratigraphic resolution from pelagic microfossils is very limited. Age markers are typically absent or occur as isolated, rare occurrences. The same interval typically contains abundant and diverse benthonic foraminifera. Considerable vertical and lateral variation exists in the species composition of these assemblages. On a local scale, these variations provide excellent field-specific and high resolution biozone schemes (e.g. from fields in NCMA-1 and Block 22). On the regional scale, many of these variations are not correlatable. The approach taken is to assess foraminiferal assemblage character to identify regionally significant trends in biofacies, particularly in the shelf-dominated Early Pliocene. Three repeatable biofacies associations are recognised across the NCMA well database: the lowermost association reflects a deep water basin plain setting (Biofacies Unit 1), followed by shelfal biofacies associations (Biofacies Unit 2), in turn followed by a return to deep marine conditions (Biofacies 3). The break between each Biofacies Unit is interpreted as representing a regional shift in palaeodepth, initially with a widespread shallowing event to establish a shelfal setting (Biofacies 1/2 boundary), followed by a regional drowning of the shelf with the return of a deep water environment (Biofacies 2/3 boundary). Within Biofacies 2, two surfaces of shallowing are used to define the top of Unit 2a and Unit 2b. Biofacies associations are used to define discrete (genetic) units of deposition for the NCMA, which are then calibrated to seismic. Landward/basinward shifts in biofacies are used to constrain the identification of specific seismic ties. NC units provide a framework for further seismic interpretation, mapping of depositional trends and predicting palaeogeography, they also represent time slices within which sandstone deposition can be characterised. NC Unit boundaries document the timing of significant landward or basinward shifts in facies. An example of the biofacies –seismic –sedimentological integration is illustrated for one NC Unit. Microfossils in Tidal Settings as Indicators of Sea-Level Change, Paleoearthquakes, Tsunamis and Tropical Cyclones Benjamin Horton1,2

1 Sea Level Research, 1Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104, [email protected] 2 Institute of Marine and Coastal Sciences, Rutgers, New Brunswick NJ 08901, USA Fine-grained sediments deposited in low-energy, inter-tidal, settings are an archive of sea-level change, and the occurrence of paleoearthquakes, tsunamis and tropical cyclones. Some of the best reconstructions of these coastal processes have been derived from microfossils such as foraminifera that accumulate in salt-marsh and estuarine environments. Early microfossil work in the coastal zone employed pollen as an indicator of vegetation and as a chronostratigraphic marker. Use of diatoms and foraminifera has become increasingly widespread because their distribution is closely linked to tidal elevation. In this paper, I will discuss the use of microfossils in estuarine and salt-marsh sediments to reconstruct sea level along subsiding coastlines in temperate regions (Figure 1). I also describe how microfossils from isolation basins are used to reconstruct sea level along coastlines experiencing uplifting coastlines. Microfossils can also estimate land-level changes along tectonically active coasts associated with paleoearthquakes. I explain the use of transfer functions for calculating quantitative estimates of past environmental conditions from microfossil data. Finally, we reveal how microfossils are used to reconstruct the recurrence of tsunamis and tropical cyclones from the sedimentary deposits these high energy events leave behind.


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Figure 1: Sea-levels of the past 2000 years. The proxy reconstructions are based upon foraminifera preserved in salt-marsh sediments of North Carolina. Organic-Walled Dinoflagellate Cysts as Tracers of Oceanographic Reorganization in the Southern Ocean Before the Onset of Full-Scale Antarctic Glaciation A.J.P. Houben1,3, S.M. Bohaty2, A. Sluijs1, H. Brinkhuis1 1 Biomarine Sciences, Faculty of Geoscsiences, Utrecht University, Utrecht, NL [email protected] 2 National Oceanography Centre, University of Southampton, Southampton, UK 3 Now at: TNO/Geological Survey of the Netherlands, Petroleum Geosciences, Utrecht, The Netherlands During the Eocene – Oligocene Transition (EOT, 34-33.5 Ma), Antarctic ice-sheets abruptly expanded leading to continental-scale glaciation. While quasi-coeval opening of southern ocean gateways has often been associated with this ‘greenhouse-icehouse’ transition, details of their precise role in changing regional oceanography and climate in the late Eocene remain elusive. Scarcity of EOT sediment sections, incomplete successions, and problems with the dating using classic techniques have hampered detailed study of the late Eocene evolution of the Southern Ocean. Here we date and correlate various Southern Ocean EOT successions using organic-walled dinoflagellate cyst (dinocyst) biostratigraphy. The results imply that the typical, and widely occurring glauconite-rich lithological units were all deposited during the late Eocene, starting at ~35.5 Ma. We ascribe this widespread phenomenon to significant invigoration of bottom water circulation. Furthermore, organic biomarker and dinocyst assemblages provide reconstructions of sea surface temperatures (SSTs), patterns of sea surface circulation and environmental change from critical regions in the Southern Ocean, now including the well-dated interval just before the EOT. Our results show that the Southern Ocean progressively cooled, yet the southwest Pacific (ODP Site 1172) experienced late Eocene warming, related to the penetration of low-latitude currents when the Tasman Gateway critically deepened. Dinocyst assemblages document a shift towards more productive, vertically mixed surface waters in areas influenced by Polar wind-driven currents. The results imply that (I) accelerated deepening of the Tasman Gateway, (II) invigorated surface and bottom water circulation at sites affected by polar westward currents, (III) enhanced sea surface productivity at these localities and (IV) cooling of the circum-Antarctic surface waters occurred simultaneously from about 35.5 Ma onwards. These positive feedbacks could have contributed to the preconditioning of the Antarctic continent for glaciation.


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Diatoms and Geochemical Records of Anthropogenic Impacts in Sediments of the Tarna-Satighat Lake, Umrer Taluka, Nagpur District, Maharashtra, India: Implications as Indicator of Trophic Status and Land-Use Change Sumedh K. Humane1*, Thierry Adatte2, Samaya S. Humane1, and Nandeshwar Borkar1 1*Postgraduate Department of Geology, Rashtrasant Tukadoji Maharaj Nagpur University, Rao Bahadur D. Laxminarayan Campus, Law College Square, Nagpur- 440 001(MS) * [email protected] 2 Institut de Géologie et Paléontologie (IGP), Université de Lausanne, Lausanne 1015 The diatom assemblage along with the CHN analysis of lake sediments retrieved in the form of core contains information that helps to reconstruct past environmental changes and to study the impact of anthropogenic activity on the local ecosystem of the Tarna-Satighat Lake of the Umrer Taluka, Nagpur District, Maharashtra, India. There is no industrialization around this lake although deforestation and use of fertilizers in the surrounding agricultural land is significant. The recovered core was analysed for diatom contents at every 10 cm intervals into the seven units i.e. Unit I (bottom) to Unit VII (top). The present research work has revealed the presence of total 34 species belonging to 17 genera of diatoms representing all the units i.e. Unit I to Unit VII (Fig. 1). The diatom inferred total phosphorous (TP) has revealed that the lake water quality has been changing cyclically from good to fair since last few decades and was mostly circumneutral to partially acidophilous and mesoeutrophic in conditions (Units I to III) and subsequently transformed to circumneutral to alkalibiontic and eutrophic in condition (Units IV to VII). High Corg/Ntotal ratios indicate that most of the sediment organic matter in this lake is from vascular land plants, which are protein-poor and cellulose-rich, which creates organic matter that usually has C/N ratios between 10.87 to 26.01. TOC content increases consistently from bottom of core to the top of core ranging between 0.13 to 3.76 suggesting previously the conditions were not much favourable for the preservation of organic matter but with the preceding time there was a change in an environment of the lake that favors preservation of organic matter. Thus, the overall variation of the TOC, C/N ratio and diatom inferred total phosphorous (TP), in the entire core suggest the cyclic fluctuations in the water quality from good to fair in the Tarna-Satighat Lake since last few decades. Despite an increase in external input of nutrients, the trophic state of the lake has remained largely unchanged and the perceived human-induced impacts are limited. Fig. 1 Explaination of Figure a) Navicula bacillum Ehrenberg (TSLC-6); b) Pinnularia cardinalis Cleve (TSLC-6); c) Navicula bacillum Ehrenberg (TSLC-6); d) Navicula bacillum Ehrenberg (TSLC-7); e) Navicula viridis Nitzsch (TSLC-7); f) Pinnularia major Kutzing (TSLC- 6); g) Aulacoseira granulate (TSLC- 7); h) Navicula radiosa Kutzing (TSLC-6); i) Pinnularia cardinalis Cleve (TSLC-7); j) Stauroneis phoenicentron Ehernberg (TSLC -8); k) Amphora libyca Ehernberg (TSLC -5); l) Aulacoseira granulate (TSLC -7); m) Stauroneis phoenicentron Ehernberg (TSLG -1/17); n) Stauroneis sp.(TSLC- 7); o) Stauroneis anceps Ehernberg (TSLC- 8) p) Stauroneis sp. (TSLC- 7) q) Stauroneis phoenicentron Ehernberg (TSLC- 8); r) Amphora normanii (TSLC- 7) ; s) Melosira sp. (TSLC-8); t) Craticula cuspidate Kutzing (TSLC-7); u) Cyclotella sp. (TSLC- 7)


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Detecting Baffle Shales Using Microfossils: An Integrated Working Example from a Miocene Gom Development Project Sarah-Jane Jackett1, Rui Da Gama1, Brendan Lutz1, Zane Jobe2, Heidi Albrecht3 and Tushar Prasad3 1Applied Stratigraphy and Paleontology, Shell International Exploration and Production, 200 North Dairy Ashford, Houston, Texas 77079-1197. [email protected] 2 Clastics Research, Shell International Exploration and Production, Westhollow, Houston, Texas 77082-3101 3 Fluid Evaluation & Sampling, Shell International Exploration and Production, 200 North Dairy Ashford, Houston, Texas 77079-1197 The Auger TLP in the Gulf of Mexico started producing in 1994 from multiple Pliocene amalgamated channel and sheet reservoirs on the north side of the Auger salt dome. Since 2011, operations have targeted the upper Miocene


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sheet sands (below LAD Globigerinoides mitra and Discoaster berggrenii, collectively named U-sand) on the south side of the salt dome, in order to increase the Auger TLP life expectancy. To date biostratigraphy has been a critical tool in developing this field. Drilling the edge of a salt mini-basin, velocity models often require correction and in some cases have errors of up to 7,000ft. In addition, biostratigraphy is used to avoid penetrating an over pressured mid-Miocene formation associated with an unconformity below the U-Sand. This project presents biostratigraphy as another tool to investigate reservoir compartmentalization (Holmes 1999, Payne et al. 1999). In 2011, 180ft of core from the upper and lower U-sand reservoirs was collected primarily in order to define completion procedures. The lower U-sand is underlain by a shale and a 50ft thick shale separates the upper and the lower U-sands. We are interested in the lateral extent of these shales and their potential to form barriers to fluid flow and compartmentalize the reservoir. Thirty five core samples were collected from the two shale intervals and examined for percentage sand content, XRF with full clay analysis, nannofossil content, planktic and calcareous benthic foraminifera abundances and diagnostic agglutinate foraminifer morphogroups (Charnock and Jones 1985, Murray et al. 2011). Combining these data, three distinct environmental signals can be interpreted: 1) Relatively stable, quiescent environment at the base of the cored interval below the reservoirs. There is an even representation of agglutinate morphogroups with equilibrium populations (K-strategists, e.g. Cyclammina spp., Textularia spp., and Trochammina spp.), very little or no nannofossil reworking, a significantly higher percentage of mixed illite/smectite clays, a lower infaunal:epifaunal, higher abundances of in-situ planktic foraminifers and planar laminations. This shale is hemipelagic in nature (similar to a MFS) and is usually more laterally extensive and a more effective barrier to fluid flow. 2) Fast changing, chaotic environment is recorded directly below the lower U sand. This interval shows evidence of transport with a spike in reworked Cretaceous nannofossils, accompanied by an increase in infauna (possibly representing dysoxic conditions), followed by a primary colonizer pulse indicating initial recovery. Above this interval the contact with the overlain U-sand is erosional. 3) Mixed environment with a relatively higher allochtonous component, represented by colonizing/pioneering assemblages (r-strategists, e.g. Bathysiphon spp., Liebusella spp.), a pulse of reworked Cretaceous nannofossils, a higher percent sand content and bioturbation. A vertical gradation from a mixed environment to a more stable setting is recorded within the intra-reservoir shale. This indicates a reduction in energy and a relative increase in hemipelagic influence: an environment conducive to the formation of baffles. Whilst several published and unpublished examples of microfacies work exist, in this example we integrate data with oil finger-printing and WFT pressures. This shows that microfacies analyses is a robust method in thick shales to assess reservoir compartmentalization and hence, impact the reservoir model and the placement of producer wells. This technique is especially applicable to unconventional assets where compartmentalization is currently being overlooked. Holmes, N. A. 1999. The Andrew Formation and ‘biosteering’ — different reservoirs, different approaches. Geological Society,

London, Special Publications 1999, v.152; 155-166. Jones, R.W., and Charnock, M. 1985. `Morphogroups' of agglutinating foraminifera. Their life positions and feeding habitats and

potential applicability in (palaeo)ecological studies. Revue de Paléobiologie, 4: 311-320. Murray, J. W., Alve, E. and Jones, R. 2011. A new look at modern agglutinated benthic formainiferal morphogroups: their value in

paleoecological interpretation. Paleogeography, Paleoclimatology, Paleoecology 309, 22-241. Payne, S. N. J., Ewen, D. F. and Bowman, M. J 1999. The role and value of 'high-impact biostratigraphy' in reservoir appraisal and

development. Geological Society, London, Special Publications 1999, v.152; 5-22. Characterization of Shell Concentration and Taphonomic Analysis of Maniyara Fort Formation in Kutch Basin, India Pankaj Khanna1,2 and Pramod Kumar2 1Rice University, Department of Earth Science, 6100 Main Street, MS-126, Houston, Texas 77005 [email protected] 2University of Delhi, Department of Geology, Delhi, 110007, India Shell concentration is defined as any relatively dense accumulation of coarse (>2 mm) bioclasts or biomineralized remains from any invertebrates1. As a complex repository of biostratigraphic and palaeoenvironmental data, it is


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considered as a potential source of information about a sedimentary basin’s depositional history. On the basis of stratigraphic, sedimentologic, paleontologic and taphonomic attributes4,5, the fossiliferous limestone beds of Maniyara Fort formation are characterized into shell concentration types and help to identify the depositional environment as shallow marine, evolving in the Oligocene from a deepening to a shallowing upward sedimentary successions.. The Kutch basin evolved as a peri-cratonic rift basin during the Mesozoic and evolved as a passive margin sag-basin during the Cenozoic along the western margin of India. Cenozoic sediments lie over the Deccan Traps and are divided into eight formations. Oligocene sediments in the Kutch Basin are represented by the Maniyara Fort Formation which is divided into four members: Basal Member, Lumpy clay Member, Coral limestone Member and Bermoti Member2. Three river sections namely, the Rodasar, Berwali and Waior rivers were measured and described in great details. Fossiliferous limestone bed thickness in these river sections vary from 30 cm to 2 m separated by poorly fossiliferous to barren silty shales/siltstones. Qualitative data sets acquired in the field were used to designate limestone beds into shell concentration types. Quantitative data of individual skeletal elements for their taphonomic attributes were plotted in ternary taphograms to enhance the qualitative taphonomic data acquired from the field. Two types of shell concentration have been identified: event concentration and composite shell concentration (hydraulic and biostromal composite concentration)1,3. The hydraulic composite concentration comprises of 75-100 cm thick limestone bed which show extensive fragmentation and reorientation of Nummulities indicating post-mortem reworking by repeated wave/current action. Biostromal composite concentration is thicker (75 cm to 2 m) with respect to the co-occurring limestones in the formation displaying matrix supported fabric, randomly oriented shells, low to moderate fragmentation, angular edges of shells; major faunal content include corals, Nummulities and Lepidocyclina. Event concentration is included in 30–70 cm thin limestone beds displaying pristine shells, concave up and concave down valves of pecten, low- moderate fragmentation, matrix supported and major faunal content include Pecten and Nummulities. After incorporating taphonomic attributes in a ternary taphogram along with standard sedimentological, paleontological and stratigraphic aspects the depositional environment of the Oligocene succession of the western Kutch is interpreted to represent a shallow marine environment initially representing a deepening succession in early Oligocene and evolving into a shallowing succession in late Oligocene. Kidwell, S.M., 1991. The stratigraphy of shell concentrations. In: Allison, P.A., Briggs, D.E.G. (Eds.), Taphonomy. Releasing the

data locked in the fossils record. Plenum Press, New York, pp. 115-209. Biswas, S.K., 1992.Tertiary stratigraphy of Kutch. Journal of the Palaeontological Society of India 37, 1-29. Kumar, P., Saraswati, P.K. and Banerjee, S. (2009) Early Miocene Shell Concentration in the mixed Carbonate- Siliciclastic System

of Kutch and their Distribution in Sequence Stratigraphic Framework, Journal Geological Society of India, Vol. 74, October 2009, pp. 432-444.

Kowalewski, M., Flessa, K.W., Aggen, J.A., 1994. Taphofacies analysis of Recent shelly cheniers (beach ridges), northeastern Baja California, Mexico. Facies 31, 209-242.

Davies, D.J., Powell, E.N., Stanton, R.J. Jr., 1989. Taphonomic signature as a function of environmental processes: Shell and shell beds in a hurricane-influenced inlet on the Texas coast. Palaeogeography, Palaeoclimatology, Palaeoecology 72, 317-356.

Evolution of the Genus Aspidolithus in the Upper Cretaceous Western Interior Basin Zachary A. Kita and David K. Watkins University of Nebraska – Lincoln [email protected] Anagenesis of Aspidolithus parcus subspecies has been studied previously using light microscopy and scanning electron microscopy (Lauer, 1975; Hattner et al., 1980; Wise, 1983). The genus Aspidolithus is important to Upper Cretaceous biostratigraphy. Aspidolithus parcus subspecies are used as zonal and subzonal markers in the Campanian (Thierstein, 1976; Sissingh, 1977; Perch-Nielsen, 1979; Wise 1983). Three subspecies of Aspidolithus parcus are recognized: A. p. parcus, A. p. constrictus, and A. p. expansus. The first occurrence of A. p. parcus marks the base of the Campanian calcareous nannofossil zone CC18a (Perch-Nielsen, 1985), while the bases of CC18b and CC18c are marked by the first occurrences of A. p. cf. constrictus and A. p. constrictus, respectively. Previous studies (Lauer, 1975; Hattner et al., 1980; Wise, 1983) detailed the linear evolution of Aspidoltihus parcus subspecies from A. p. expansus to A. p. constrictus. Lauer (1975) noted four changes which occurred through time: (1) increase in size, (2) increasing difference in the diameter of the three rim tiers, (3) reduction in the size of the central area, and (4) reduction in the number of pores in the central area. Hattner et al. (1980) recognized changes 1, 3, and 4 but not 2. Observation of pores has been problematic due to overgrowth or dissolution of the central area. The Niobrara Formation in western Kansas contains the entire evolutionary progression from Aspidolithus parcus expansus to Aspidolithus parcus constrictus and exhibits excellent preservation of nannofossils. Measurements of the


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total coccolith length, total coccolith width, central area length, and central area width were taken for biometric analysis of Aspidolithus parcus subspecies throughout its range. Results indicate a statistically significant difference between the three subspecies based on central area width vs. outer rim width (a diagnostic characteristic for subspecies differentiation). In addition, an overall size increase is observed in Aspidolithus through the section in agreement with Lauer (1975). These above results are then applied to a geochronologic framework. Hattner, J.G., Wind, F.H., Wise, S.W., 1980. The Santonian-Campanian boundary: comparison of nearshore-offshore calcareous

nannofossil assemblages. Cahiers De Micropaleont., 3, p. 9-26. Lauer, G., 1975. Evolutionary trends in the Arkhangelskiellaceae (calcareous nannoplankton) of the Upper Cretaceous of Central

Oman, SE Arabia. In. Neol. D., Perch-Nielsen, K. (eds.): Report of the consultant groups on calcareous nannoplankton, Kiel: Archives des Sciences, Geneve, 28, p. 259-262.

Perch-Nielsen, K., 1979. Calcareous nannofossils from the Cretaceous between the North Sea and the Medierranean. In. Wiedmann, J., (ed.): Aspekte der Kreide Europas, International Union of Geol. Sci., Series A, p. 223-272.

Perch-Nielsen, K., 1985. Mesozoic calcareous nannofossils. In Bolli, H.M., Saunders, J.B., Perch-Nielsen, K. (eds.): Plankton Stratigraphy, Cambridge, Cambridge University Press, p. 329-426.

Sissingh, W., 1977. Biostratigraphy of Cretaceous calcareous nannoplankton. Geol. Mijinbouw., 56, p. 37-65. Thierstein, H.R., 1974. Calcareous nannoplankton: Leg 26, Deep Sea Drilling Project. Initial Rep. Deep Sea Drill. Proj., 26, p. 619-

667. Wise, S.W., 1983. Mesozoic and Cenozoic calcareous nannofossils recovered by Deep Sea Drilling Project Leg 71 in the Faulkland

Plateau Region, Southwest Atlantic Ocean. Initial Rep. Deep Sea Drill. Proj. 71, p. 481-550. Planktic Foraminiferal Biostratigraphy and Paleoclimatic Interpretations of Holocene-Late Pleistocene Core MD02-2535, Tunica Mound, Gulf of Mexico Adriane R. Lam1, Kristen St. John1, and R. Mark Leckie2 [email protected] of Geology and Environmental Science, James Madison University, MSC 6903, Harrisonburg, VA 22807; 2Department of Geosciences, University of Massachusetts, 611 N. Pleasant St., Amherst, MA 01003 The primary purpose of this study was to develop an age model for Calypso Core MD02-2535 from Tunica Mound, northern Gulf of Mexico, using planktic foraminiferal biostratigraphy. Twenty-two bulk samples were dried, weighed, and sieved at 150 µm. The >150 µm fraction was split and identified to species level to characterize the assemblage. Biostratigraphic zones were assigned based on zonation schemes and species frequency patterns defined by Ericson and Wollin (1968) as modified for the Gulf of Mexico by Kennett and Huddlestun (1972). The upper 0.19 m of core represent the Z1 planktic foraminifera subzone. The Z1/ Z2 subzone boundary lies at 0.24 mbsf and is assigned an age of 6 ky. The Z/Y boundary is located at 0.94 mbsf, correlating to the beginning of the Holocene at 10 ky. The Y1 subzone captures the Younger Dryas, located between 0.98 and 1.10 mbsf, and the warming trend that preceded it. The Y1/Y2 boundary lies at approximately 1.80 m, and is assigned an age of 16 ky. The base of the Y2 subzone is assigned an age of 24 ky and lies at 2.85 mbsf. The Y2 subzone includes the Last Glacial Maximum, located at 2.30 mbsf, based on the high abundances of G. inflata, G. falconensis, and G. bulloides in this interval. We suspect the age of core section VII does not exceed the Y6 subzone at 68 ky because the first ash layer correlating with MIS 4 was not detected. Sedimentation rates and planktic foraminfera mass accumulation rates were calculated for the purpose of interpreting paleoenvironmental changes and their drivers. Sedimentation rates are highest in the Z2 subzone at 18.4 cm/ky, likely due to the massive influx of sediment flushed into the Gulf by meltwater from the Laurentide Ice Sheet associated with the last deglaciation (Flower and Kennett, 1990). Sedimentation rates slow to 4 cm/ky in the Z1 subzone, owing to rising sea level reducing sediment input into the farther offshore Gulf sites, and to avulsion processes within the Mississippi River delta. Sedimentation rates in this core are much slower than those found from cores drilled in the Pigmy and Orca basins, where they range from 0.21 m/ky to 2 m/ky in the Z zone and 0.5 m/ky to 2.2 m/ky in the Y1 subzone. This is expected due to the drill location being atop a sea mound not influenced by sediments flushed into the Gulf from the Mississippi River. Mass accumulation rates (MARs) of planktic foraminifera are relatively low throughout much of the Pleistocene at 30-134 g/cm3/ky. MARs increase dramatically into the Holocene and peak at 4791 g/cm3/ky in the Z2 subzone at 8.9 ky. This sharp increase in production may be due to increased nutrients brought into the Gulf by runoff and the Mississippi River meltwater spike after the Younger Dryas. MAR declines to 555 g/cm3/ky into the Z1 subzone at 1.75 ky. Modern sediment trap data from the Gulf of Mexico indicate that species of Globigerinoides tend to reach maximum flux during spring and summer months while N. dutertrei reach maximum flux during fall and winter months (USGS, 2011). Varying abundances of these species seen throughout the core could be a paleo-seasonal signal. Neogloboquadrina dutertrei responds greatest to changes in the thermocline, increasing in abundance when shoaling occurs (Thunell and Reynolds, 1984) or when nutrients are input to the surface water system from land runoff. The


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greatest abundances of N. dutertrei occur in the Y1 subzone, correlating with the end of the LGM and transition into the Holocene. In the modern Gulf of Mexico, Globigerinoides sacculifer reaches maximum flux during winter and spring months, and again in the summer (USGS, 2011). In our paleo-record, G. sacculifer reaches maximum abundances between 6.0 mbsf and 7.80 mbsf in the core, at a time when abundances of N. dutertrei are at their lowest. Perhaps the abundance peaks of G. sacculifer indicate meltwater spikes and lower salinity associated with MIS 3.

Stable δ18O and δ13C analyses were carried out to test the hypothesis of Brunner (2007) that local gas hydrates may compromise the utility of stable isotopes for paleoenvironmental interpretations. Contaminated specimens would be expected to exhibit very negative δ13C values, as methane (CH4) is an isotopically light compound. However, isotopic data were compared to the planktic foraminiferal oxygen and carbon isotopic record from other sites in the Gulf of Mexico, and the values were well within “normal” ranges. Measured δ18O isotope values from Globigerinoides ruber (pink) range from -1.59‰ to -1.22‰ in the Holocene, and from -3.67 to -2.19 in the late Pleistocene. Measured δ18O isotope values from N. dutertrei range from -0.05‰ to 0.74‰ in the Holocene, and from 0.22‰ to 3.08‰ in the late Pleistocene. Holocene δ13C values range from 1.56‰ to 2.04‰ in G. ruber (pink), and from 1.86‰ to 2.08‰ in N. dutertrei. Late Pleistocene δ13C values range from 1.09 ‰to 1.59‰ in G. ruber (pink), and from 0.24‰ to 2.44‰ in N. dutertrei. Therefore, we conclude that methane did not contaminate δ18O or δ13C isotopes in calcium carbonate tests from this particular core location. The stable δ18O and δ13C isotopic records of G. ruber and N. dutertrei were compared and two intervals of low productivity were identified as interpreted from low δ13C values and elevated abundances of Globigerinoides spp. The first interval starting at 2.30 mbsf correlates with the end of the LGM and continues to 2.80 mbsf. The second interval from 5.80 mbsf to 7.80 mbsf, possibly correlates with MIS 3. Both intervals display elevated abundances of G. sacculifer and negative δ18O values, possibly indicative of enhanced glacial melt runoff leading to low salinity values within the ocean’s mixed layer. Interestingly, we found that δ13C values are heavier than expected for the thermocline species N. dutertrei, compared to the mixed layer species G. ruber (pink), with abnormal values beginning around 14.2 ky, or 1.55 mbsf. This anomaly could indicate complex seasonal variation in the structure of the water column, since Globigerinoides spp. tend to reach maximum flux rates in spring and summer months while Neogloboquadrina dutertrei reach maximum flux rates during fall and winter months. The heavier δ13C signal of the thermocline species N. dutertrei suggests shoaling of the thermocline and higher productivity during winter months since the LGM. Brunner, C.A. Qualitative planktonic foraminiferal biostratigraphy of core MD02-2570, of late Quaternary age, from the northern Gulf

of Mexico; chapter 11 in Winters, W.J., Lorenson, T.D., and Paull, C.K., eds. 2007, Initial report of the IMAGES VIII/PAGE 127 gas hydrate and paleoclimate cruise on the RV Marion Dufresne in the Gulf of Mexico, 2–18 July 2002: U.S. Geological Survey Open-File Report 2004–1358.

Ericson, D.B., and Wollin, G., 1968, Pleistocene climates and chronology in deep-sea sediments: Science, v. 162, p. 1227-1234

Flower, B.P., and Kennett, J.P., 1990, The Younger Dryas cool episode in the Gulf of Mexico: Paleoceanography, v. 5, no. 6, p. 949-961.

U.S. Geological Survey. Gulf of Mexico Climate and Environmental History. Jan. 10, 2011, U.S. Department of the Interior. Dec. 6, 2012. < www.coastal.er.usgs.gov /gom/research/calibration.html>

Kennett, J.P., and Huddlestun, P., 1972, Late Pleistocene paleoclimatology, foraminiferal biostratigraphy and tephrochronology, Western Gulf of Mexico: Quaternary Research, v. 2, p. 38-69.

Thunell, R.C., and Leslie, A.R., 1984, Sedimentation of planktonic foraminifera: Seasonal changes in species flux in the Panama Basin: Micropaleontology, v. 30, p. 243-262.

The status and evolution of Paragloborotalia during the Oligocene to early Miocene R. Mark Leckie1, Lyndsey Fox2, Andrew Fraass1, Richard Olsson3, Paul Pearson4, Isabella Premoli Silva5, Silvia Spezzaferri6, and Bridget Wade2 [email protected], 1University of Massachusetts, Amherst MA; 2University of Leeds, United Kingdom; 3Rutgers University, Piscataway NJ; 4Cardiff University, United Kingdom; 5University of Milan, Italy; 6University of Fribourg, Switzerland The Paleogene Planktic Foram Working Group is tasked with updating and standardizing the taxonomy and systematics of all Paleogene and early Neogene planktic foraminifera. To date, the Paleocene Atlas (Olsson et al., 1999) and Eocene Atlas (Pearson et al., 2006) have been published, and a digital version of each is available online at the Chronos Portal (website URL) and on the Smithsonian Institution website (URL). Currently, the Oligocene Atlas is in development, with publication anticipated for 2014. This report on the status and evolution of the genus Paragloborotalia is part of that effort. The genus Paragloborotalia is a long-ranging genus that witnessed accelerated evolutionary activity during the transition to icehouse conditions as meridional temperature gradients increased during Oligocene and early Miocene


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time. A number of the Paragloborotalia species are particularly characteristic of the tropics and subtropics, including the nana-opima, siakensis-mayeri, and pseudokugleri-kugleri lineages. Mid-latitude temperate lineages are known as well (nana-semivera-acrostoma; nana-incognita-zealandica). Isotope paleoecology suggests that some species were mixed layer dwellers (e.g., P. pseudokugleri, P. kugleri), while others were upper thermocline dwellers (e.g., P. nana, P. siakensis; Pearson and Wade, 2009). The genus Paragloborotalia evolved in the early Eocene (Pearson et al., 2006). There are 12 Oligocene-Miocene species of Paragloborotalia that are considered valid senior synonyms: P. acrostoma, P. birnageae, P. continuosa, P. incognita, P. kugleri, P. mayeri, P. nana, P. opima, P. pseudocontinuosa, P. pseudokugleri, P. semivera, and P. siakensis. Paragloborotalia is characterized by 4 to 7 chambers in the final whorl, a cancellate (honeycomb), macroperforate wall, low trochospire, rounded or subrounded periphery, and low to arched umbilical-extraumbilical aperture; many of the taxa have thickened rim or lip bordering the aperture. The issue of spinosity in Paragloborotalia (Cifelli, 1982) has been controversial due in large measure to the fact that spines or spine holes are very rarely preserved on these taxa. However, indisputable evidence for the presence of spines has been demonstrated for P. siakensis (Zachariasse and Sudijono, 2012) and P. kugleri (Rögl, 1996; Spezzaferri, 1991) Paragloborotalia nana gave rise to P. siakensis, P. semivera, P. opima, and P. pseudocontinuosa in the mid-Oligocene, followed by P. pseudokugleri in the late Oligocene and P. incognita in the earliest Miocene. P. opima is distinguished from its ancestor by a larger size and less-embracing chambers. The extinction of large P. opima is a reliable marker datum for the base of Zone P22/Zone O6 (27.5 Ma; Wade et al., 2007, 2011). The lowest occurrence of P. pseudokugleri is used to define the base of Zone O7 (25.9 Ma) in the new zonal scheme of Wade et al. (2011). The transition from P. pseudokugleri to P. kugleri marks the base of Neogene in the low latitudes and the total range of P. kugleri (23.73 to 21.81 Ma) defines Zone N4/Zone M1 (Wade et al., 2011). In the upper part of Zone N4/Zone M1b, P. kugleri gave rise to P.? peripheroronda, which is transitional in wall texture between the paragloborotaliids and the smoother-walled and keeled Fohsella of the middle Miocene. P. incognita gave rise to Globoconella zealandica and G. praescitula in the early Miocene. The latter taxa gave rise to the globorotaliid radiation of the middle and late Miocene, including Globorotalia, Hirsutella, Menardella, and the other species of Globoconella. P. pseudocontinuosa gave rise to P. continuosa in the earliest Miocene, which is the ancestor of the late Miocene Neogloboquadrina. Chaisson, W., and Leckie, R.M., 1993. High-resolution Neogene planktonic foraminiferal biostratigraphy of Site 806, Ontong Java

Plateau (western equatorial Pacific). Proceedings of the Ocean Drilling Program, Scientific Results, 130:137-178. Cifelli, R., 1982. Early occurrences and some phylogenetic implications of spiny, honeycomb textured planktonic foraminifera.

Journal of Foraminiferal Research, 12:105-115. Kennett, J.P., and Srinivasan, M.S., 1983. Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., 265 p. Leckie, R.M., Farnham, C., and Schmidt, M., 1993. Oligocene planktonic foraminiferal biostratigraphy of Hole 803D (Ontong Java

Plateau) and Hole 628A (Little Bahama Bank), and comparison with the southern high latitudes. Proceedings of the Ocean Drilling Program, Scientific Results, 130:113-136.

Olsson, R.K., Hemleben, C., Berggren, W.A., and Huber, B.T. (editors) 1999. Atlas of Paleocene Planktonic Foraminifera. Smithsonian Contributions to Paleobiology, 85, 252 p.

Pearson, P.N., Olsson, R.K., Huber, B.T., Hemleben, C., and Berggren, W.A. (editors) 2006. Atlans of Eocene Planktonic Foraminifera. Cushman Foundation Special Publication, 41, 514 p.

Pearson, P.N., and Wade, B.S., 2009. Taxonomy and stable isotope paleoecology of well-preserved planktonic foraminifera from the uppermost Oligocene of Trinidad. Journal of Foraminiferal Research, 39(3):191-217.

Rögl, F., 1996. Paragloborotalia kugleri. An index fossil for the Paleogene/Neogene boundary. Giornale di Geologia, ser. 3, 58:151-155.

Spezzaferri, S., 1991. Evolution and taxonomy of the Paragloborotalia (Bolli) lineage. Journal of Foraminiferal Research, 21:313-318. Spezzaferri, S., 1994. Planktonic foraminiferal biostratigraphy and taxonomy of the Oligocene and lower Miocene in the oceanic

record. An overview. Palaeontographica Italica, 81, 187 p. Wade, B.S., Berggren, W.A., and Olsson, R.K., 2007. The biostratigraphy and paleobiology of Oligocene planktonic foraminifera

from the equatorial Pacific Ocean (ODP Site 1218). Marine Micropaleontology, 62:167-179. Wade, B.S., Pearson, P.N., Berggren, W.A., and Palike, H., 2011. Review and revision of Cenozoic tropical planktonic foraminiferal

biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth-Science Reviews, 104:111-142. Zachariasse, W.J., and Sudijono, 2012. New data on the morphology and classification of the Oligocene-Miocene planktonic

foraminifer Paragloborotalia siakensis (LeRoy, 1939). Journal of Foraminiferal Research, 42(2):156-168.


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Preliminary interpretation of phylogenetic relationships of Oligocene-early Miocene Paragloborotalia. Stratigraphic range data based primarily on Kennett and Srinivasan (1983), Chaisson and Leckie (1993), Leckie et al. (1993), and Spezzaferri (1994). Time scale from Wade et al. (2011).

The Discovery of Tenuitellids from the Uppermost Paleocene to Middle Eocene in the Equatorial Pacific Ocean, Praetenuitella Antica N. Sp.: A Macro to Microperforate Planktic Foraminifer Lizette Leon-Rodriguez1,2, R. Mark Leckie3 and Gerald R. Dickens1

1Rice University; Houston, TX.;2now at ExxonMobil Corp., Exploration Company; Houston, TX., [email protected]; 3University of Massachusetts; Amherst, MA

We describe Praetenuitella antica, a newly identified species of planktic foraminifera that lived during the latest Paleocene to middle Eocene. It is reported after examining sediment at two deep-sea drilling sites in the eastern Pacific Ocean (ODP Site 1215 and IODP Site U1333). Specimens show characteristics of the genus Praetenuitella Li, which is resurrected and emended in this study. The new species has is macroperforate and moderately pustulose in the earliest chambers, and is microperforate and sparsely pustulose in the latest chambers. Morphometric analysis shows this species to be small (~100 µm maximum diameter), with 4 to 5 chambers in the last whorl that slowly increase in size. Intraspecific variability is low, although specimens occasionally have a kummerform last chamber. Considering possible phylogenetic relationships, the genus Praetenuitella is likely related to Tenuitella suggesting that this plexus is 20 Myr older than previously recorded. Stable oxygen isotope data from Praetenuitella antica n.sp. indicate that this species likely lived in shallow waters but with a wide range of temperatures (18 to 24oC). Stable carbon isotope values, from -0.63 to -0.47 ‰, are significantly lower than those of co-existing acarininids and morozovellids. These data may indicate that Praetenuitella antica n.sp. grew rapidly and incorporated isotopically 13C-depleted metabolic carbon into the test. Despite their small size, tests of this species are fairly resistant to dissolution, so specimens are preserved in horizons with low carbonate content. Carbonate and Planktic Foraminiferal Accumulation in the early Paleogene. The record at ODP Site 1215, Eastern Equatorial Pacific Ocean Lizette Leon-Rodriguez1,2, Gerald R. Dickens1, and R. Mark Leckie3 1Rice University; Houston, TX.; 2now at ExxonMobil Corp., Exploration Company; Houston, TX., [email protected]; 3University of Massachusetts; Amherst, MA. Carbonate accumulation and planktic foraminiferal preservation are examined in sediment deposited at ODP Site 1215 before, during, and after four hyperthermal events of the early Paleogene (PETM, ~55.5 Ma; H1/ETM2, ~53.7 Ma; I1, ~53.2 Ma, and K/X, ~52.5 Ma). The hyperthermals are characterized by very low accumulation of carbonate and planktic and benthic foraminifers. Within 200 kyr after each event, there is an overall improvement in carbonate accumulation and foraminiferal preservation. Planktic foraminiferal assemblages follow a predicted pattern for selective dissolution. Species of the genus Acarinina and “Praetenuitella” are preferentially preserved over Morozovella. While, the genera Subbotina, Igorina, and Globanomalina appear to be more susceptible to dissolution. Changes in the oxygen isotope record and foraminiferal assemblages also suggest that warm-‐water dwellers (Acarinina and Morozovella) appear soon after the hyperthermals, but cooler-water dwellers (Praetenuitella) prevail over the long term.

P. pseudokugleri P. kugleri

P. birnageae

P.? peripheroronda P. nana

P.? incognita Globoconella zealandica

G. praescitula

P. nana P. opima

P. continuosa P. pseudocontinuosa

P. siakensis P. semivera

P. acrostoma

P. mayeri

Neogloboquadrina lineage

Fohsella lineage

Globoconella, Hirsutella, Menardella, & Globorotalia lineages?

?


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The Use of Taphonomic Grade and Biovolume Data to Supplement Relative Abundance: Benthic Foraminifera from San Salvador, Bahamas R.D. Lewis*, H.R. Tichenor, O.C. Turner, and J.L. Morgan, * Auburn University, Auburn, AL 36849-5305, [email protected] Biofacies in distributional studies of foraminifera have traditionally been based on counts of 300 specimens per station along transects, analyzed by cluster analysis of relative abundance data. The determination of individuals that were live at the time of collection typically has been and continues to be based on Rose Bengal staining despite well-known problems with this method. Studies vary from those that treat only live specimens to those that examine the total assemblage without attempting to discriminate between live and dead. The smallest screen size is usually 63 mµ, although larger sizes are often used in carbonate-producing ecosystems. Other modifications in reefal environments include the use of natural color (due to symbionts) instead of staining, and the “sieve method” of Marin and Liddell (1988), wherein each size fraction is picked separately and is weighted equally. Attached (encrusting) foraminifera pose additional challenges and are often overlooked or are under-represented in sampling. Standard methods may not yield distinct biofacies even though these may be apparent by qualitative inspection. Reasons for this include (1) the under-emphasis given to rare but significant taxa, (2) the role of dead tests with their range of taxonomic conditions, and (3) differences in relative size (biovolume) of different taxa. These issues are especially evident in shallow-water carbonate-producing environments, where high water energy combined with biologically induced test degradation leads to a wide range of taphonomic states, and sizes of tests commonly differ by orders of magnitude. These aspects are discussed and illustrated in case studies drawn from recent research: seagrass-bed foraminifera (Buchan and Lewis, 2010; Morgan and Lewis, 2010) and attached foraminifera found on cobbles (Tichenor and Lewis, 2011), all of which took place on the island of San Salvador, Bahamas. In the first study (Buchan and Lewis, 2010) investigated the relationships between relatively large (> 1 mm) benthic foraminifera living on vegetation and those found (live and dead) in the sediment in order to evaluate the extent to which foraminiferal assemblages and densities can serve as proxies for taxonomic make up and density of seagrass beds. Live versus dead determinations were made based on the presence or absence of colored cytoplasm when wet, and each dead test was categorized taphonomically in order to determine the level of post-mortem alteration according to the following scheme: pristine, good, altered, or extremely altered. Taphonomic condition of the assemblage as a whole was assessed by the quality of preservation index (QPI): the percent of live, pristine, and good tests in an assemblage. Because 6% or less of the specimens found in the seafloor sediment were live, the data encoded in dead tests were particularly valuable. The composition of foraminiferal assemblages found in the sediment did not accurately reflect the standing populations on the vegetation; thus, they were not found to be a useful proxy for the taxonomic composition of seagrass beds. However, taphonomic analysis showed that the assemblages were indicators of the former existence and relative densities of vegetation beds. For example, the assemblages found in medium- to high-density seagrass beds were dominated by tests in pristine to good condition, typically with QPI values of 70-85%. Morgan and Lewis (2010) did a similar study of substrate control but included filamentous algae attached to cobbles and smaller as well as relatively large foraminifera. The smaller phytal foraminifera, mostly rotaliids, proved to be important and showed a strong preference for vegetation type, apparently reflecting the specific shape of the plant or algal substrate. Live/dead ratios ranged from 0.46 (cobbles) to 0.1 (sand), and QPI values ranged from 92.8% (seagrass and macroalgae) to a low of 79.4% (sand), supporting the earlier finding. Foraminifera cemented to the underside of cobbles were evaluated to examine possible zonation from shoreline to platform margin and in a range of habitats including different reef types (Tichenor and Lewis, 2011). The primary data set consists of counts taken within 10-cm2 quadrats; attached specimens were counted and their taphonomic conditions were recorded as explained above. Traditional methods of cluster analysis based only on abundance data proved unsatisfactory: zonation results not only from differences in relative abundance of the same taxa in different habitats, but also from differences in assemblage taphonomic state (QPI). In addition, unusually large differences in test size were seen because of the presence of Gypsina plana. Attached foraminifera found near shore on the west (lee) and north sides of the island were highly abundant and were dominated by nearly pristine Homotrema/Miniacina; on the east (windward) side, Homotrema/Miniacina was less common in near-shore samples. Mid-shelf assemblages, including patch reefs, varied with locality, although all had abundant Planorbulina. Bank-barrier reef assemblages were similar to those near the shore but showed more diversity and a greater abundance of Gypsina plana. Shelf margin assemblages were the most distinct because they were dominated by the large, sheet-like Gypsina plana; other taxa were sparse and poorly preserved as shown by low QPI values. Data on area covered


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were added to the counts of individuals by the application of ImageJ to photographs. This resulted in further clarification of the biofacies outlined above. Buchan, O.C., and Lewis, R.D., 2010, Recent large benthic foraminifera as indicators of grassbed characteristics, San Salvador,

Bahamas: The addition of taphonomy: in Demchuk, T.D., and Gary, A.C., eds, SEPM Special Publication No. 93, Geologic Problem Solving with Microfossils, p. 83-92.

Martin, R.E., and Liddell, W.D., 1988, Foraminiferal biofacies on a north coast fringing reef (1-75m), Discovery Bay, Jamaica: Palaios, v. 3, p. 298-314.

Morgan, J.L., and Lewis, R.D., 2010, Benthic foraminiferal assemblages at Cut Cay: A microcosm study of the effects of water energy and substrate preference, San Salvador, Bahamas: Proceedings of the 14th Symposium on the Geology of the Bahamas and other Carbonate Region, p. 150-162.

Tichenor, H.R., and Lewis, R.D., 2011, Zonation of attached (encrusting) foraminifera across a small carbonate platform, based on species assemblages and area covered, San Salvador, Bahamas: Geological Society of America Abstracts with Programs, vol. 43, no. 2, p. 71.

Foraminiferal Evidence of Paleoceanographic Transitions in the Cenomanian-Turonian Eagle Ford Shale Across Southern Texas Christopher M. Lowery1; Matthew Corbett2; R. Mark Leckie1; David Watkins2; T. Scott Staerker3 and Art Donovan3 1University of Massachusetts, Amherst, [email protected] 2University of Nebraska, Lincoln 3BP America, Houston The Eagle Ford Shale of southern Texas has seen renewed interest in recent years because of its new importance as a shale gas target. Lost in the petroleum exploration is the fact that this Cenomanian-Turonian dark gray organic-rich shale also occupies an important gateway between the epeiric Western Interior Seaway of North America to the open marine Gulf of Mexico/Tethys. This important transition between two well-studied regions has never been the focus of a comprehensive paleoecological study until the present time. This study consists mainly of quantitative foraminiferal population counts combined with associated sedimentary particles, including inoceramid prisms, sand grains, and pyrite grains, and carbonate and organic carbon isotope data from three main sites: an outcrop in Lozier Canyon in Terrell County, west of Langtry, TX, an outcrop at Bouldin Creek outside of Austin, TX, and the Swift Fasken A #1H well in Webb County, TX. These three sites represent a range of paleo water depths: a shallow water carbonate platform (Lozier Canyon), a submarine plateau of intermediate depth (Swift Fasken) and a proximal, shallow carbonate slope (Bouldin Creek). Supplemental data have been included from several other wells that have been the focus of qualitative industry biostratigraphic efforts. Our data indicate three separate paleoenvironments at the study sites in the Eagle Ford Group. First, an open-ocean, high productivity environment located in the most distal section, on the Rio Grande Submarine Plateau, between two Early Cretaceous reef margins. Second, a normal-marine, low productivity environment to the north in the shallower sites near Austin, Texas. Third, a high-productivity, occasionally stressed environment on the Comanche Platform with a strong Western Interior affinity. Foraminifera assemblages show two distinct groups: a western-interior affinity assemblage that shows faunal trends similar to those found in the seaway to the northwest, and a new, open water assemblage that lacks faunal indicators of a shallow seaway. The carbon isotope excursion associated with Oceanic Anoxic Event 2 (OAE2) is a reliable datum across the Eagle Ford, and records diachronous changes in foraminiferal populations, particularly the highest occurrence of Rotalipora cushmani, which track paleoceanographic changes across south Texas. Planktic foraminiferal biostratigraphic datum events suggest a middle to late Cenomanian age for the lower Eagle Ford, an early Turonian unconformity in the middle Eagle Ford that widens progressively older to the north, and a latest Turonian age for the lower Austin Chalk. This agrees with the regionally reported stratigraphic level of the inoceramid clam Cremnoceramus deformis erectus, recently proposed as a marker for the basal Coniacian. Foraminifera as Proxies for Miocene Sea Level Change and Sequence Boundaries: Observations from the Marion Plateau, ODP Leg 194 Christopher M. Lowery1, Emily Browning1,2, R. Mark Leckie1, and Cedric M. John3 1University of Massachusetts, Amherst, MA, [email protected] 2BP America, Houston, TX 3Imperial College, London, UK


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Foraminifera are best known as carriers of primary paleoceanographic and paleoclimatic information (SSTs, productivity, ice volume, etc.), but often overlooked is their utility as indicators of sea level variability. This presentation summarizes the use of planktic and benthic foraminifera to indicate sequence boundaries on a mixed siliciclastic-carbonate shelf adjacent to the Marion Plateau on the Queensland margin of northeast Australia. Although quantifying global sea level change has been a major research focus since the publication of the first sea level curves by the Exxon research group in the late 1970s, quantifying the glacio-eustatic component of sea level signals has become a priority as recent work has demonstrated that far-field effects like ice-sheet gravitation, isostasy, and changes in the earth’s rotation locally imprint on the “true” eustatic signal of waxing and waning ice sheets, so that coeval signals from disparate sites may show significantly different local sea level variation. To this end, the Miocene slope sediments on the Marion Plateau were drilled by ODP Leg 194 in an attempt to provide an independent, southern hemisphere test of the sea level record of the New Jersey Margin of North America, the most complete and oft-cited record of Late Cretaceous and Cenozoic sea level variability. The carbonate slopes adjacent to the Marion Plateau operate on the highstand shedding model, where sea level rise and highstand cause growth of the carbonate platform, which results in increased sedimentation on the platform slopes. Sea level fall and lowstand result in a decrease in carbonate production and hence a decrease in sedimentation and the formation of condensed intervals and glauconite horizons on the adjacent slopes. Foraminiferal population counts, combined with counts of other major sedimentary components (in this case: neritic fragments, such as bryozoans, echinoderms, and platform benthics, and mineral grains, such as glauconite and quartz sand) can be used to track changes in sedimentation and the formation of sequence boundaries on carbonate margins. The ratio of planktic to benthic foraminifera tracks sea level change: benthic foraminifera are abundant in shallow water environments (e.g., a carbonate platform). When sea level is high and the carbonate platform is productive, many benthic foraminifera are shed off the platform to the slope sites, and so the ratio of planktics to benthics decreases at the slope sites. When sea level falls, planktics become more prevalent, and the ratio rises; this is the opposite of what is typically observed on siliciclastic margins. Neritic fragments, mostly bits of bryozoans here, follow a similar pattern: high sea level shows increased influx of neritics to deeper water, whereas low sea level shows decreased abundances at the slope sites. Glauconite is a diagenetic seafloor mineral commonly formed in areas of low sedimentation. Autochthonous glauconite accumulation on carbonate slope environments indicates a drop in sea level and low sedimentation; we see peaks of glauconite at sequence boundaries. Sand grains only play a significant role in the sediment budget before the Northern Marion Platform (NMP) was established, when our study sites were still a muddy ramp. A large drop in sand and increase in neritic fragments heralds the inception of NMP growth. Taken together, these records show: 1) a few large sea level variations between 20 and 18 Ma, a time corresponding to a pre-platform muddy ramp; 2) short-period, high-amplitude variations between 18 and 14.8 Ma, a period of higher sea levels during the Miocene Climatic Optimum (MCO) and corresponding to the main phase of NMP growth; and 3) a dramatic spike corresponding to Mi3a at 14.8 Ma during the Middle Miocene Climate Transition (MMCT) followed by a slow decrease in the amplitude and frequency of variability during the time of Antarctic ice sheet build-up and the drowning of the Marion Plateau carbonate platform. These variations correspond directly to variations in the oxygen isotope record, suggesting these events are all driven by ice volume variability on Antarctica. Raman Spectroscopic Indicators of Thermal Maturation and Graphitization of Organic Cement in Fossil Agglutinated Foraminifera David H. McNeil1, Emily Matys2,and Tanja Bosak2

1Geological Survey of Canada, Natural Resources Canada, 3303 33rd St. NW, Calgary, AB T2L 2A7 Canada ([email protected]) 2Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, AM 02139, United States We have used Raman spectroscopy to analyze organic cement in Recent and fossil agglutinated foraminifera. Specimens were chosen from a broad range of thermal environments (burial diagenetic to low grade metamorphic) to document progressive graphitization of foraminiferal organic cement. Raman spectra of Recent and fossil agglutinated foraminifera contain classic signatures for carbonaceous matter, i.e., a “G band” for highly ordered graphitic-like carbon (peak wavelength ~1575 cm-1) and a “D band” for disordered carbonaceous material (peak wavelength ~1355 cm-1). In Recent agglutinated foraminifera, these bands are of low intensity and are associated with a strong fluorescence signal. Increasing thermal maturity of fossil samples is associated with a progressive, but non-linear, increase in the intensity of the G and D bands, a decrease in the band width relative to the intensity, and a disappearance of fluorescence. At high levels of thermal maturity (late mature oil


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window and higher), the G and D bands closely resemble the spectral signal of graphite and indicate progressive graphitization. The agglutinated foraminifera used in this study were composed predominantly of quartz grains. In Recent material, the quartz grains were well defined and organically agglutinated. Raman spectroscopy of the tests revealed a peak at ~475 cm-1 indicating silica in all specimens. The intensity of this peak increased with increasing thermal maturation, providing a measure of the silicification and crystallinity in the thermally mature test. A close correlation exists between analytical Raman data; empirical data derived using the Foraminifera Coloration Index (FCI); and vitrinite reflectance data. This correlation substantiates the use of organically agglutinated foraminifera as indicators of thermal maturation. Testing Different Techniques for Microfossil Extraction from Limestone and Marlstone R.M. Mello1,2, K. Elderbak2, C. Lowery2, and R.M. Leckie 1Petrobras Research Center (Brazil) [email protected] 2Geosciences Department, University of Massachusetts Amherst Extracting microfossils from hard carbonate-rich strata has been the focus of various studies and hence different methods have been proposed. Although thin sections are commonly used, they have many drawbacks, not the least of which is the impossibility of direct comparisons to adjacent samples that have been washed from mudrocks. Choosing the ideal method depends on the physico-chemical properties of the treated rock sample and on the type of the microfossil tests. Calcareous and agglutinated foraminiferal assemblages are traditionally extracted from fine clastic sedimentary rocks using hydrogen peroxide [H2O2] and some form of detergent or soap; however, this method is not effective for hard limestone. Three different methods have been tested for extracting foraminifera from hard limestones. These methods are: acetic acid procedure as described by Lirer (2000) and Kariminia (2004); liquid nitrogen by Remin (2012), and diluted hydrochloric acid (personal communication, Claudia Cetean 2011). Micritic limestone samples from the Upper Cretaceous Bridge Creek Limestone and Austin Chalk, USA, as well as indurated marlstones from the Eagle Ford Shale, were treated with glacial acetic acid after the method of Galeotti (pers. comm.). Limestone from the Gramamme Formation, northeastern Brazil, was treated with acetic acid following the procedure described by Kariminia (2004) with some modifications. The Bridge Creek, Eagle Ford, and Austin samples were targeted for planktic and benthic (calcareous and agglutinated) foraminiferal assemblages; the Gramamme Formation samples were mainly targeted for agglutinated benthics. Gramamme Formation samples were also treated with liquid Nitrogen described by Remin et al. (2012) and diluted hydrochloric acid (personal communication, Claudia Cetean 2011) in order to have a better recovery in agglutinated benthic foraminiferal tests. Acid dissolution yielded useable assemblages of foraminifera with minimal dissolution or etching of calcareous taxa from the limstones. Unfortunately, it was unsuccessful in extracting foraminifera from the marlstone samples. We conclude that the acetic acid is an effective procedure to extract microfossils from hard limestone, not only because it yields good recovery in samples from the Bridge Creek Limestone, Austin Chalk, and Grammame Formation, but also this procedure is safe and simple to perform (no special chemical labs). The liquid nitrogen method can produce great results as well but it is not safe and the procedure is more complicated. This method requires a specialized person to handle the nitrogen pump as well a specific aluminum bowl instead of the regular beaker (glass or plastic) used in the other two methods. The liquid nitrogen the liquid nitrogen can cause serious damages to burn skin or when inhaled. The diluted hydrochloric acid method, on the other hand, is very slow but can be very effective if the target is agglutinated foraminifera. Therefore, we recommend the application of the acetic acid method to extract foraminiferal assemblages from indurated carbonate-rich rocks because of its simplicity, safeness, and remarkable results especially for both planktics and calcareous benthics, while the application of the hydrochloric acid method works best for extracting agglutinated foraminifera from limestones. Rig-Site Palynology and Salt Tectonics: An Example from the Oligocene, Offshore West Africa Daniel Michoux Total Exploration. CSTJF, Avenue Larribau, 64000 France. [email protected] In 2008 Total’s biostratigraphy team was approached by a west-African regional office to carry out real time monitoring of an offshore well. The decision to request rig-site biostratigraphy was based on the presence of a salt canopy affecting seismic visibility, and the time it would have taken to ship samples from the rig to our laboratory facilities in southern France. Whenever possible, biostratigraphic studies performed by our group have a multi-disciplinary approach combining micropaleontology, nannofossils and palynology. The zonations used are standard schemes for the foraminifera and


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nannoplankton (Berggren et al. 1995, and Martini 1971, respectively), while the palynological zonation is an internal scheme. In the basin, comparison of the 3 zonations shows that palynology affords the best resolution in the stratigraphic interval of interest. The anticipated logistics and safety issues linked to standard, acid-based palynological processing oriented the project toward non-acid palynology. It was decided to test the technique on material from the same interval from nearby well before committing to the intervention. Samples were sent to Petrostrat, a Wales-UK based company with the relevant expertise, for evaluation. The results were tested against conventional, acid-base processing performed in Total,s laboratory and were found positive the go-ahead was given to the operation. Two interventions were led, on a vertical section, then on a deviated sidetrack. This presentation will concentrate on the sidetrack. The task force was made of a palynologist from Total Exploration and a senior technician seconded by Petrostrat. The “non-acid paly kit” was also assembled by Petrostrat. The monitoring started below the salt canopy and continued down to TD. The operation lasted 12 days. The average processing time was an hour for a 20 µm sieving, 75-90 minutes when an above 20 µm and a 10 to 20 µm fractions where needed. 6 to 7 slides were processed and analyzed in a 12-14 hours shift. 24 hours coverage would have required 2 technicians and 2 palynologists. This is standard North Sea practice but is difficult to implement in West Africa, where POB was found to be an issue. Recovery proved very good throughout the intervention. In the Rupelian, several hundred dinocysts were sometimes counted under a 24mm x 24mm square coverslip. Even in the Chattian, which is much poorer than the Rupelian in the area, the slides contained enough dinocysts to confidently identify the zonal markers and their acmes. Rapid changes in assemblages, reflecting faulting and thrusting linked to salt movements, were immediately picked up by the palynologist on the rig, and the onshore geological team was able to integrate them into their modeling in near real time. The results of this offshore, non acid intervention, a first for Total, were later validated by a standard, shore-based palynological study, which brought only minor improvements as a result of closer sample spacing. This led the affiliate to request a second intervention on a development well in 2011. Using Marine Diatoms to Reconstruct Holocene Climate Events and Ice Shelf History: Multi-Proxy Investigation of Sediment Cores from Herbert Sound, NE Antarctic Peninsula Rebecca Totten Minzoni1, John B. Anderson1, Rodrigo Fernandez2, and Julia Smith Wellner3

1Rice University, Department of Earth Science, 6100 Main Street, MS-126, Houston, Texas 77005 [email protected] 2 University of Texas Institute for Geophysics, Jackson School of Geosciences, J.J. Pickle Research Campus, Bldg. 196,10100 Burnet Road (R2200), Austin, TX 78758-4445 3University of Houston, Department of Earth and Atmospheric Sciences, University of Houston, 4800 Calhoun Road, Houston, Texas, 77204-2693 The Antarctic Peninsula (AP) is currently one of the three most rapidly warming regions on the planet1,2. The southward shift of mean annual isotherms due to regional atmospheric warming may be responsible for recent catastrophic break-up of several ice shelves, including the largest observed break up, Larsen B in March of 20023,4,5,6,7. This is explained by the observation that ice shelves exist in atmospheric temperatures less than -9°C, and become instable and disintegrate when mean annual temperatures rise above that threshold3,6,8. In drainage systems associated with disintegrated ice shelves, glacial flow has accelerated due to loss of protective buttressing, causing concern for the mass balance of the Antarctic Peninsula Ice Cap10. Specifically, Cook and colleagues noted that 87% of the 244 glaciers in the AP region have receded in the last 60 years11. Are the southward shift of isotherms, the loss of ice shelves, and the recession of glaciers part of a natural climate cycle, or unique to the recent? Our research aims to address this question by putting the historic glacial record into a longer-term, geologic context. Here we show high-resolution core and seismic data from the high-accumulation, well-preserved, and chronologically well-constrained sedimentary record of Herbert Sound (HBS) in the northeastern AP. HBS is a large fjord located offshore James Ross Island (JRI), which would be an anchor point for advancing Larsen and Prince Gustav ice shelves, were the -9°C isotherm to shift north of 64°S latitude. Due to its easterly location and unique orography and oceanography, HBS is also an ideal locale for studying the response of glacial and marine systems to climatic events of the Holocene. Of particular interest are responses to the Mid Holocene Warm Period and the Late Holocene Neoglacial events, and how the timing of these responses compares with other AP fjords of different local forcings on glacial stability. High-resolution seismic, sedimentology, geochemistry, and micropaleontology reveal an abrupt transition from ice proximal to distal glacimarine conditions in HBS ~ 8.6 ka. Recently conducted diatom assemblage analysis reveals


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subtleties in the record that have previously been undistinguishable. The assemblages suggest a shift from sub-ice shelf to open marine conditions with high seasonal sea ice concentration following deglaciation ~8.6 ka, followed by a pronounced ocean warming ~7.4 ka during the Mid Holocene Warm Period (MHWP), and an increase in sea ice concentration ~ 2.5 ka during the Late Holocene Neoglacial. Thus, HBS became open marine ~8.6 ka with no evidence of subsequent glacial re-advance, implying that the Larsen Ice Shelf and the -9°C isotherm have remained south of 64°S since the early Holocene. This corroborates with Brachfield and colleagues’ study of the former Larsen A Ice Shelf, which suggests the 1995 collapse was unprecedented in the Holocene10, but not with Pudsey and Evans’ IRD provenance study under the former Prince Gustav Ice Shelf in which they propose mid-Holocene ice shelf collapse11. It is probable the -9°C isotherm oscillated to the south, while never reaching north of 64°S after initial collapse ~8.6 ka. Lastly, the paleoclimate record lends valuable information about HBS that can be compared with the new JRI ice core12. The MHWP was pronounced in HBS with both ocean surface and atmospheric temperatures at or above present day. An increase in sea ice concentration in HBS ~2.5 ka correlates with decreasing atmospheric temperatures, and is evidence for the existence of the Late Holocene Neoglacial in the AP. This implies that the Neoglacial is a global phenomenon rather than a Northern Hemisphere and Patagonian event. Houghton, J. T., Ding, Y., Griggs, D. J., Noguer, M., van den Linden, P. J., Dai, X., Maskell, K., and Johnson, C. A., 2001, "Climate

Change 2001: The Scientific Basis." Cambridge University Press, Cambridge. Vaughan, D. G., Marshall, G. J., Connolley, W. M., Parkinson, C., Mulvaney, R., Hodgson, D. A., King, J. C., Pudsey, C. J., and

Turner, J., 2003, Recent rapid regional climate warming on the Antarctic Peninsula. Climatic Change, v. 60, p. 243-274. Doake, C. S. M. and Vaughan, D. G., 1991, Rapid disintegration of the Wordie Ice Shelf in response to atmospheric warming,

Nature, v. 350, p. 328–330. Vaughan, D. G. and Doake, C. S. M., 1996, Recent atmospheric warming and retreat of ice shelves on the Antarctic Peninsula,

Nature, v. 379, p. 328–331. Morris, E. M., and Vaughan, D. G., 2003, Spatial and temporal variation of surface temperature on the Antarctic Peninsula and the

limit of viability of ice shelves. Antarctic Research Series, v. 79, p. 61-68. Scambos, T., Hulbe, C., and Fahnestock, M., 2003, Climate-induced ice shelf disintegration in the Antarctic Peninsula. Antarctic

Research Series, v. 79, p. 79-92. Scambos, T. A., J. A. Bohlander, C. A. Shuman, and P. Skvarca, 2004, Glacier acceleration and thinning after ice shelf collapse in

the Larsen B embayment, Antarctica, Geophys. Res. Lett., p. 31. De Angelis, H. and Skvarca, P., 2003, Glacier surge after ice shelf collapse. Science, v. 299, p. 1560–1562. Cook, A., Fox, A. J., Vaughan, D. G., and Ferrigno, J. G., 2005, Retreating glacier-fronts on the Antarctic Peninsula over the last 50

years, Science, v. 22, p. 541–544. Brachfield, S., Domack, E., Kissel, C., Laj, C., Leventer, A., Ishman, S., Gilbert, R., Camerlenghi, A., and Eglinton, L.B., 2003,

Holocene History of the Larsen-A Ice Shelf constrained by geomagnetic paleointensity dating. Geology, v. 31, p. 749-752. Pudsey, C.J., and Evans, J., 2001, First survey of Antarctic sub-ice shelf sediments reveals mid-Holocene ice shelf retreat. Geology,

v. 29, p. 787-790. Mulvaney, R., Abram, N. J., Hindmarsh, R. C. A., Arrowsmith, C., Fleet, L., Triest, J., Foord, S. (2012). Recent antarctic peninsula

warming relative to holocene climate and ice-shelf history. Nature (London), v. 489(7414), p. 141-144. The South China Sea: Proto-Warm Pool Development and the East Asian Monsoon Stephen A. Nathan1* and R. Mark Leckie2 1Eastern Connecticut State University 2University of Massachusetts Amherst *[email protected] During the middle to late Miocene, changes in tectonics and sea level profoundly impacted both global climate and ocean circulation. We document the interplay between the constriction of the Indonesian Seaway, the uplift of the Himalaya-Tibetan Plateau, and changes in sea level that brought irrevocable changes to the South China Sea (SCS) and the western equatorial Pacific. Deep sea sediments collected from Ocean Drilling Program Sites 806 (Ontong Java Plateau), 1146 (northern South China Sea), and 1143 (southern South China Sea) were analyzed for planktic foraminiferal assemblages and multi-species planktic and benthic foram stable isotopes. A mixed layer species, Globigerinoides sacculifer, and upper thermocline species, Globorotalia menardii, were used to examine changes in the structure and productivity of the upper water column for the interval ~13.4 Ma to ~5.6 Ma. Eustatic changes of the late middle Miocene to early late Miocene (Miocene isotope event 4 through Mi6) contributed to the initiation of a proto-warm pool and transformed the SCS into a semi-enclosed basin or a basin with restricted flow across the Sunda Shelf. This configuration of the SCS may have lasted until sea level began to rise after ~9.0 Ma or later, as noted by a decrease in Δδ18OTH-ML (THermocline species – Mixed Layer species) and a decrease in δ18OTH. At ~8.5 Ma, an increase in thermocline taxa, coincident with complementary changes in the carbon and oxygen isotope records, may signal the onset/intensification of the East Asian monsoon and possibly non-warm pool conditions in the SCS (i.e., the thermocline may have begun to shoal, as it did at Ontong Java Plateau; Nathan and


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Leckie, 2009). For the northern SCS, the non-warm pool state may have lasted until the end of the record presented here while in the southern SCS the limited record is less conclusive. The figure shows continuous planktic foraminiferal stable isotope and population assemblage data for ODP Sites 806 (Ontong Java Plateau; Panel A, blue), 1146 (northern South China Sea; Panel B, green), and 1143 (southern South China Sea; Panel C, red). For all panels: percent thermocline species abundances shown by solid filled curve along left margin of panel (thermocline assemblage = Neogloboquadrina spp., Globorotalia spp.), continuous records of stable oxygen isotope ratios (δ18O) for upper thermocline species (dark solid diamonds = G. menardii, G. fohsi) and mixed layer species (light open circles = G. sacculifer). Panels A – C also depict five point running averages. Sites 806 and 1146 initially display pre-Indonesian Seaway closure as recorded by relatively low thermocline abundances and narrow isotope gradients (δ18O thermocline species minus δ18O mixed layer species). After 12.5 Ma stable isotope gradients at both sites widen considerably and thermocline populations rise at Site 806, with the former proxy indicating a deepening thermocline at both sites (La Nina-like conditions, the onset of a Proto-Warm Pool) and the later proxy recording the closure of the seaway at Ontong Java. After 8.5 Ma, all three sites show a significant rise in the running averages of thermocline species abundances, with Site 806 showing this increase as early as 9.6 Ma, indicating a shoaling thermocline and the absence of Proto-Warm Pool conditions (El Nino-like conditions; Nathan and Leckie, 2009). These assemblage changes are accompanied by a narrowing of the stable isotope gradient between thermocline and mixed layer species. After 6.6 Ma, Site 806 species abundances decline and the isotope gradient widens, indicating a return to La Nina-like conditions for the remainder of the record, while Sites 1143 and 1146 maintain an El Nino-like state (non-Proto-Warm Pool).

Percent thermocline species and multispecies oxygen isotope data from the western equatorial Pacific (Ontong Java Plateau; ODP Site 806), northern South China Sea (ODP Site 1146), and southern South China Sea (ODP Site 1143). Closed symbols: upper thermocline Globorotalia menardii; open symbols: mixed layer Globigerinoides sacculifer. Arrows depict warming (red) and cooling (blue) in the upper thermocline and near-surface. High Resolution Biostratigraphy and Sequence Stratigraphic Regional Correlation of Ten Wells in the Western Niger Delta Basin, Gulf of Guinea Ogbaa Nnukwu Chevron Nigeria Limited [email protected]


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The Sequence Stratigraphic correlation of the Early Pleistocene to Late Miocene intervals of ten offshore wells drilled in the Western Niger delta, Gulf of Guinea is proposed for this paper. The project confirms the importance of high resolution biostratigraphy as a vital tool in the recognition and correlation of geological sequences provided the correlation between wells is constrained by Seismic data. The Sequences are correlated and dated with selected biostratigraphic marker events. The absolute age dates generated from the high resolution biostratigraphic analysis of the ten wells were used to establish a consistent succession of events that were integrated with seismic. The chronostratigraphic surfaces recognized formed the basis for the calibration of the seismic section. Based on the results of the sequence stratigraphic analysis carried out on the ten wells, a number of chronostratigraphically significant correlatable datums, mostly maximum flooding surfaces (MFS), absolute ages and sequence boundaries (SB) were identified. One lithogenetic unit of the Agbada formation was recognized and there is a general consistency in the lithology, lithofacies and textural characteristics in all the wells. A major depocenter was noted at the study area between the Inner and Outer Trends. The Inner Trend wells were the oldest (Late Miocene to Late Pliocene), while the youngest are the Outer Trend wells (Late Pliocene to Early Pleistocene). Eight Maximum Flooding Surfaces and Sequence Boundaries dated in millions of years were recognized and confirmed on the well logs in the ten wells. The sedimentary package of the area of study is subdivided into two megastructures or depocenters (Northern Depocenter and Southern Depocenter) separated by a shale ridge. Each depocenter is limited by a regional growth fault and an associated counter-regional fault. The Miocene to Recent sedimentary section presents a succession of sub-parallel and sub-horizontal sequences and the seismic data presents only local evidence characteristic reflection terminations. Direct correlation between the depocenters is highly difficult using the available seismic data. The sequence stratigraphic framework established by the biostratigraphic data was presented mainly as absolute ages of the condensed sections because the logs were incomplete. The sequences are tentatively subdivided into ten sequences in the northern depocenter and six sequences in the southern depocenter. The environmental synthesis of the ten wells in the study area suggests environment of deposition that varied between Coastal Deltaic and shallow marine while deeper marine conditions were attained in some of the wells in the Outer Trend. The MFS’s recognized primarily by high resolution biostratigraphy provides the most useful and most reliable regional correlation surfaces that significantly guided the seismic correlation especially in areas of structural complexity. Careful integration of biostratigraphy peaks, interval high gamma ray values and seismic regional low amplitude continuous reflectors is needed to produce consistent correlatable events. The project conclusively shows that with a well integrated biostratigraphy, well log analysis and seismic study, high resolution sequence stratigraphy has the potential to significantly improve the quality of seismic interpretation resulting to the identification of new reservoirs. But to achieve this goal, biostratigraphers must work in collaboration with earth scientists and well log analysts. Challenges

• Incompleteness of well log data provided hampered the quality of seismic to well ties • Local poor seismic quality due to the tectonic complexity in some areas • Old age and poor preservation of ditch cuttings samples • Absence of core data • Errors associated with depth conversion in seismic • Lack of in-depth knowledge of stakeholders in the application of biostratigraphy

Lessons learned • Preserve available cores and ditch cuttings for biostratigraphic analysis. • Work closely with stakeholders during integration of data • Involve key SMEs when using biostratigraphy data • should have basic training on the use of Biostratigraphic software and processing methods • Correlating across major structure building/growth faults building seismic integration work could be very

challenging Best Practices

• For better resolution, analyze every sample, avoid compositing • Regional approach rather than single well analysis should be encouraged • Uniform standard for data presentation within corporation. • Sequence boundaries and maximum flooding surfaces to be considered should have regional consistency • Integrate biostratigraphic data, well logs and sequence stratigraphy into Exploration and Asset team

correlation work.


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SDAR a New Quantitative Toolkit for Analyze Stratigraphic Data John Ortiz1, Carlos Moreno1, Surangi W. Punyasena2, Andrés L. Cárdenas1, and Carlos Jaramillo1 1Smithsonian Tropical Research Institute, Ancón, República de Panamá 2Department of Plant Biology, University of Illinois, USA Since the foundation of stratigraphy geoscientists have recognized that data obtained from stratigraphic columns (SC), two dimensional schemes recording descriptions of both geological and paleontological features (e.g., thickness of rock packages, grain size, fossil and lithological components, and sedimentary structures), are key elements for establishing reliable hypotheses about (a) the distribution in space and time of rock sequences, and (b) ancient sedimentary environmental and paleobiological dynamics. Despite the tremendous advances on the way geoscientists store, plot, and quantitatively analyze sedimentological and paleontological data (e.g., Macrostrat [http://www.macrostrat.org/], Paleobiology Database [http://www.paleodb.org/], respectively), there is still a lack of computational methodologies designed to stratigraphically examine data from a highly detailed SCs. Given this issue, we have developed the sofware ‘Stratigraphic Data Analysis in R’ (SDAR), which stores in a database all sedimentological, stratigraphic, and paleontological information collected from a SC, allowing users to generate a high-quality graphic plot (including one or multiple features stored in the database). SDAR also encompasses quantitative analyses helping users to quantify stratigraphic information (e.g. grain size, sorting and rounding, proportion of sand/shale). Additionally, it enables the users to export biostratigraphic information recorded at specific SCs into a maximum likelihood-based method, which allows for an estimate of the geological age of a sample or sets of samples with defined confidence intervals. Finally, given that the SDAR analysis module, has been written in the open-source high-level computer language “R graphics/statistics language” [R Development Core Team, 2012], it will be possible in the near future to include complex analyses such as lithofacial correlations, by a multivariate comparison between empirical SCs with quantitative lithofacial models established from modern sedimentary environments. The Cenozoic Gonyaulacacean Dinoflagellate Genera Operculodinium Wall, 1967 and Protoceratium Bergh, 1881 and their Phylogenetic Relationships Manuel Paez-Reyes1,2 and Martin J. Head1

1Department of Earth Sciences, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario L2S 3A1, Canada; 2Current Address: Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón, Republic of Panama. e-mail: [email protected] To clarify the systematic positions of the important gonyaulacacean genera Operculodinium Wall, 1967 diagnosis emended by Matsuoka et al., 1997 and Protoceratium Bergh, 1881, we present in detail the tabulation of the Oligocene–Pleistocene, thermophilic, cyst-defined species Operculodinium bahamense Head in Head and Westphal, 1999 diagnosis emended, and the extant, cosmopolitan, theca-defined species Protoceratium reticulatum (Claparède and Lachmann, 1859) Bütschli, 1885. Both species have a sexiform hyposomal tabulation, and L-type ventral organization. Protoceratium reticulatum has dextral torsion of the hypotheca, requiring assignation of the genus to the subfamily Cribroperidinioideae Fensome et al., 1993, whereas Operculodinium bahamense has neutral torsion requiring assignation to the subfamily Leptodinioideae Fensome et al., 1993. The stratigraphic range of this subfamily is now extended upwards to the lower Pleistocene. Paradoxically, Protoceratium reticulatum produces a cyst whose morphology requires attribution to the genus Operculodinium, either implying polyphyletic origins for this genus or that combinations of ventral organization and torsion used to subdivide the family Gonyaulacaceae cannot always be applied rigidly. In detail, Operculodinium bahamense is shown to have an unusual ventral tabulation in which the first apical homolog does not touch the sulcus. The new term “episert” is proposed to describe this plate relationship, which appears to have evolved independently in several lineages of the order Gonyaulacales. Greenhouse Climates, Pelagic Ecosystems, Oxygen Minimum Zones, and the Metabolic Hypothesis Paul N. Pearson and Eleanor H. John School of Earth and Ocean Sciences, Cardiff University, Cardiff CF10 3AT, United Kingdom. [email protected]. The ‘metabolic hypothesis’ suggests that temperature-related increases in the metabolic rates of ocean plankton might account for the relative paucity of organic carbon that was deposited by the greenhouse ocean of the Eocene (Olivarez Lyle and Lyle, 2006, Paleoceanography v. 21, PA2007). According to this idea, faster metabolic rates by heterotrophs in the pelagic water column resulted in more efficient remineralization of carbon at shallower sinking depths than is the case today. We find support for this in a series of reconstructed Eocene carbon isotope depth


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profiles based on well-preserved planktonic foraminifer assemblages from Tanzania and Mexico. We constructed these profiles by fitting the oxygen isotope palaeotemperatures given by an array of species to modeled water column temperatures for their localities extracted from an Eocene General Circulation Model with greenhouse climate forcing. Our results indicate relatively sharper carbon isotope gradients in the upper water column than is commonly the case today, consistent with faster remineralization. More broadly, during times of global warmth, pelagic ecosystems seem to have been generally focused in a narrow depth range above a relatively shallow and intense oxygen minimum zone. As cooling progressed, so the oxygen minimum descended, broadened, and de-intensified which, together with improved food supply at depth, allowed planktonic foraminifera (and presumably other zooplankton) to exploit deeper mesoplanktonic niches. The evolution of the deep-dwelling planktonic foraminifer Hantkenina in the middle Eocene may be one example of this. These results have implications for the distribution and focus of organic carbon deposition in greenhouse climates. Progress in the Accuracy and Resolution of the Late Cretaceous Planktonic Foraminiferal Biozonation: Diversification of Dicarinella and Marginotruncana and Biostratigraphic Implications Maria Rose Petrizzo1, Francesca Falzoni1, Brian T. Huber2 1Dipartimento di Scienze della Terra “A. Desio”, Università degli Studi di Milano, via Mangiagalli 34, 20133 Milano, Italy. 2Department of Paleobiology, MRC NHB 121, Smithsonian National Museum of Natural History, Washington, D.C. 20013-7912, U.S.A. [email protected] A recurrent feature in the evolutionary history of the planktonic foraminifera is the modification from unkeeled and globigeriniform ancestors to keeled and globorotaliform descendants. Single-keeled trochospiral taxa first appear in the Albian and correspond to a pronounced species diversification associated with an increasing degree of calcification and test size. The acquirement of peripheral double-keels is an evolutionary novelty first observed in the uppermost Cenomanian-lower Turonian assemblages. Double-keeled specimens are traditionally included in the genus Dicarinella if all the umbilical sutures are radial and depressed, whereas those forms with raised and sigmoidal to curved umbilical sutures have been included in Marginotruncana. After the extinction of the single-keeled rotaliporids close to the Cenomanian/Turonian boundary, the recovery of keeled planktonic foraminifera was relatively slow in the basal Turonian and then progressively accelerated. This diversification is well documented by the appearance of several species of Dicarinella and Marginotruncana that dominate the Turonian-Santonian assemblages. Superimposed on this evolutionary trend are occurrences of common transitional forms yielding morphological features in between Dicarinella and Marginotruncana (i.e., umbilical sutures initially raised then depressed and/or initially radial then curved, and combined patterns of the sutures), so that some of the diagnostic characters currently used to discriminate genera appear inadequate. In an effort to determine the ancestor-descendant relationships among species of Dicarinella, Marginotruncana and taxa possessing intermediate morphological features, the well preserved and highly diversified planktonic foraminiferal assemblages recovered at Tanzania Drilling Project (TDP) Sites 31 and 39 (coastal Tanzania; see Jiménez Berrocoso et al., 2012) and at Ocean Drilling Program (ODP) Sites 762 and 763 (Exmouth Plateau; see Petrizzo et al., 2011) have been studied. The morphological features displayed by the Turonian to Santonian keeled taxa have been analyzed for reconstructing lineages of descendants based on stratophenetic observations. Results confirm that some of the keeled taxa assigned to Dicarinella and Marginotruncana derive from different ancestral species (i.e., Gonzalez Donoso and Linares in Robaszynski et al., 1990). Moreover, our findings and observations are used to revise the current classification scheme, to derive a more accurate sequence of bioevents that appear to be promising for regional and global correlations, and for refinement of the planktonic foraminiferal biozonation. Jiménez Berrocoso A., Huber B.T., MacLeod K.G., Petrizzo M.R., Jacqueline A. Lees J.A., Ines Wendler I., Helen Coxall H.,

Mweneinda A. K., Falzoni F., Birch H., Singano J.M., Haynes S., Cotton L., Wendler J., Bown P.R., Robinson S.A., Gould J. (2012). Lithostratigraphy, biostratigraphy and chemostratigraphy of Upper Cretaceous and Paleogene sediments from southern Tanzania: Tanzania Drilling Project Sites 27 to 35. Journal of African Earth Sciences, v. 70, p. 36-57.

Petrizzo, M.R., Falzoni, F., and Premoli Silva, I. (2011). Identification of the base of the lower-to-middle Campanian Globotruncana ventricosa Zone: Comments on reliability and global correlations. Cretaceous Research, 32, 387-405.

Robaszynski F., Caron M., Dupuis C., Amedro F., Gonzalez Donoso J-M., Linares D., Hardenbol J., Gartner S., Calandra F., Deloffre R. (1990). A tentative integrated stratigraphy in the Turonian of central Tunisia: formations, zones and sequential


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stratigraphy in the Kalaat Senan area. Bulletin Centres Recherches Exploration-Production Elf Aquitaine 14, 213–384. Correlating Mediterranean Shallow Water Deposits with Global Oligocene–Miocene Stratigraphy and Oceanic Events Werner E. Piller1, Markus Reuter1, Marco Brandano2, Mathias Harzhauser3

1 Institute for Earth Sciences, University of Graz, Heinrichstrasse 26, 8010 Graz, Austria, [email protected] 2 Dipartimento di Scienze della Terra, La Sapienza Università di Roma, P. A. Moro 5, 00185 Roma, Italy 3 Natural History Museum Vienna, Geological-Paleontological Department, Burgring 7, 1010 Vienna, Austria The Oligocene–Miocene transition is of particular interest for the development of the Mediterranean Sea. At this time, the convergence of Africa and Eurasia impacted the Circum-Mediterranean region by a complex pattern of changing seaways and landbridges and caused the reorganization of current patterns. These geodynamic changes were amplified by drastic climate changes in the course of the long-term, stepwise global cooling, which led from the Paleogene greenhouse to the modern icehouse earth. Shallow water sediment records have the strong potential to display sensitive environmental changes in sedimentary geometries and skeletal content. However, the time resolution of most shallow water carbonate records is not high enough to be compared with climatic events as recorded in the deep sea sediment archives. In order to resolve the paleoceanographic and -climatic changes during the Oligocene–Miocene transition in the Mediterranean shallow water carbonate systems with the best possible time resolution, we re-evaluated the Decontra section on the Maiella Platform (central Apennine, Italy), which acts as a reference for the correlation of Oligocene–Miocene shallow water deposits in the Mediterranean region. The widely continuous carbonate succession is composed of larger foraminiferan, bryozoan and corallinacean limestones interlayered with distinct planktonic foraminiferal carbonates representing a mostly outer neritic setting. Integrated multi-proxy and facies analyses indicate that CaCO3 and total organic carbon contents as well as natural gamma radiation display only local to regional processes on the carbonate platform and are not suited for stratigraphic correlation on a wider scale. In contrast, new biostratigraphic data allow correlation of the Decontra stable carbon isotope record to the global deep sea carbon isotope record. This links relative sea level fluctuations, which are reflected by facies and magnetic susceptibility changes, to third-order eustatic cycles. The new integrated bio-, chemo-, and sequence stratigraphic framework enables a more precise timing of environmental changes within the studied time interval and identifies Decontra as a key locality for correlating not only shallow and deep water sediments of the Mediterranean region but also on a global scale. Record of Diatoms During the Middle-Late Miocene in Colombian Pacific Coastal, Ladrilleros-Juanchaco Sector, Valle Del Cauca A. Plata1,2*; M.A. Bárcena1; J.A. Flores1; A. Pardo2; F.J. Sierro1; F. Vallejo1,2 & R. Trejos-Tamayo1,2

1. Grupo de Geociencias Oceánicas (GGO), Departamento de Geología, Facultad de Ciencias, Universidad de Salamanca, Salamanca (Spain). 2.Instituto de Investigación en Estratigrafía (IIES), Departamento de Geología, Facultad de Ciencias Exactas y Naturales, Universidad de Caldas (Colombian) *[email protected], [email protected] Geological studies in the Colombian Pacific basins are scarces, due to few available stratigraphic wells and poor rock exposures. Drilled wells in southwestern Colombia, for example in Tumaco basin, reveal the presence of oil and gas, suggesting an important hydrocarbon potential, still unexplored. The purpose of the Agencia Nacional de Hidrocarburos-ANH, the Instituto de Investigación en Estratigrafía-IIES at Caldas University, in agreement with Salamanca University, is to develop studies for understanding the geological evolution of these areas. The initial target is the definition of a chrono-stratigraphic framework using pollen and spores, calcareous nanofossils, foraminifera and diatoms. In this study we are showing some results obtained with diatoms and silicoflagellates recovered from the northwest Pacific Colombian coast (The Ladrilleros - Juanchaco section). The record of diatoms is restricted to two intervals at the top of the sedimentary sequence (Figure 1). The first interval (414 - 470m) reveals dissolution as well as high abundance of fragmented specimens and domain of dissolution-resistant species (Actinocyclus ingens). The second interval (626 - 683.5m) is characterized by the best preservation. The first interval is characterized by continuous record of Araniscus lewisisanus, Crucidenticula nicobarica, and Actinocyclus ingens, corresponding with the Coscinodiscus lewisianus Biozone (Barron, 1985). This assemblage is correlated CN5a and CN5b nannofossil Zone, based on last common occurrence (LCO) Discoaster kugleri, which


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has its at 11,86 Ma (Raffi et al., 2006). This assemblage suggests an age no younger than 12,92 Ma, according Barron (1985) with of the last occurrence of A. lewisianus (C. lewisianus) to the Candy & Kent (1992) time scale. The second interval is characterized for a continuous record of Craspedodiscus coscinodiscus and Actinocyclus ellipticus var. spiralis and the last occurrence of Denticulopsis punctata f. hustedtii allowing identification of the Craspedodiscus coscinodiscus Biozone of Barron (1985b), suggesting an age older than 11,0 Ma (Candy & Kent, 1992). This assemblage is correlated with the CN6 nannofossil Zone, based on the presence of Catinaster coalithus, which has its first occurrence at 10,8Ma (Raffi et al, 2006). The diatoms report older ages than calcareous nannofossils. These different ages suggest the existence of a diachronous diatom assemblage, indicating that diatoms in the coastal region have different ages than in offshore. The high abundance of Thalassionema nitzschioides, Thalassiothrix longissima and Rhizosolenia spp as well as some specimens of Actinoptychus spp., Leptocilindrus danicus and Melosira sulcata, reveal a coastal upwelling environment and a cold trend at the top of the sequence. Benthic diatoms and a continuous record of silicophytoliths palm indicate an increased in the input of continental material. Figure 1. Diatom biostratigraphy. Diatom biozones tops and bottom are absent. Upper scale represents absolute abundance (solid line) in valvesx104/g. Lower scale corresponds to relative abundance (pointed line) in % of biostratigraphic marker species observed in Ladrilleros-Juanchaco section. Calcareous nanofossils biozones (Okada & Bukry 1990), Diatom biozones (Barron 1985).

Barron, J.A. 1985. Late Eocene to Holocene diatom biostratigraphy of the equatorial Pacific Ocean. Raffi, I., Backman, J., Fornaciari, E., Pälike, H., Rio, D., Lourens, L.J., Hilgen, F.J., 2006. A review of calcareous nannofossil

astrobiochronology encompassing the past 25 Million years.


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Cande, S.C., & Kent, D. V., 1992. A new geomagnetic polarity time scale for the Late Cretaceous and Cenozoic. Diversity of Caribbean Benthic Foraminiferal Assemblages Through the Closure of the Central American Seaway Crystal Pletka and Laurel S. Collins Florida International University, [email protected] The closure of the Central American Seaway had a major impact on marine habitats and organisms in both the Caribbean Sea and the tropical Eastern Pacific Ocean. The Isthmus of Panama began shoaling and affecting deep circulation in the Early Neogene, and shallower depths beginning as early as 13 Ma during the middle Miocene. Collins et al. (1996a) suggested that at approximately 8 Ma, there was some barrier between the surface waters of the equatorial Pacific and the Caribbean based on the oceanic affinities of shallow-water benthic foraminifera. There was then a deepening of the Panama isthmian strait at approximately 6 Ma that allowed deeper interchange between the surface waters of the tropical Eastern Pacific and the Caribbean. It was determined that around 4.7 Ma, a sill of <100 m depth had shoaled to restrict water exchange between the tropical Eastern Pacific and Caribbean based on the subsequent increase in δ18O values in the Caribbean. Another increase at 4.2 Ma showed the stepwise constriction of flow. Samples of benthic foraminifera from the Caribbean deep sea were examined for species composition and diversity, mostly a product of shifting paleobiogeography, over the course of the progressive closure of the Central American Seaway. Benthic foraminiferal assemblages were picked from fifteen samples, spanning 12 million years, of ODP core 999a (Leg 165) in the Colombian Basin. Cluster analyses grouped samples according to their ages, with similar samples being those about 7-15 Ma, a time corresponding to before and during early shoaling of the isthmus (Figure 1). The samples show a diversity low during the early shoaling, a slight rise during pre-closure, and a peak immediately following complete closure (Figure 2). These early results are being investigated further with paleoceanographic indicator taxa and extended back to the early Miocene.

Figure 1. Cluster Analysis of fifteen Caribbean samples, ODP Site 999a.


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Figure 2. Fisher’s α diversity graph for fifteen samples from the Caribbean, ODP Site 999a.

Getting to Grips with a High-Resolution Biostratigraphic Record and the Morphological Evolution of Obscurely-Shaped Planktonic Foraminifera Globigerinoides fistulosus Chris Poole*1, Bridget Wade1, Tom Dignes2, and Erik Anthonissen2

1School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK; 2Chevron Energy Technology Company, 1500 Louisiana, Houston, TX 77002, USA. * [email protected] (Chris Poole) Revision of planktonic foraminifer bioevents is an integral component of Cenozoic chronostratigraphy. A prime example of this critical need for bioevent recalibration is the case of the morphologically ‘obscure’ tropical species Globigerinoides fistulosus (Fig. 1; ranging from the late Pliocene to Pleistocene). G. fistulosus is extensively utilised as a biostratigraphic marker species and has been used to approximately demarcate the former base of the Pleistocene in previous studies (e.g. Parker 1967; Chaisson & Leckie 1993; Chaisson & Pearson 1997; Chaisson & D’Hondt 2000; Sinha & Singh 2008). However, despite its biostratigraphic potential, previous data show inconsistencies in the reported timing of its extinction (last appearance datums; LADs) and calibration to the geomagnetic polarity timescale. To a certain extent, the discrepancies in the LADs may be attributed to differences in taxonomic interpretation of the species definition. The species evolved from Globigerinoides sacculifer in a gradual ‘pseudospeciation’ event; developing a large, flattened final chamber, with spectacular and peculiar finger-like projections (Kennett & Srinivasan 1983). A comparable situation has been documented for the G. fistulosus extinction; a gradual morphological transition involving the demise of intricate forms and returning to G. sacculifer forms (see Chaisson & Pearson 1997). An unanswered question remains: Why did Globigerinoides experiment with such elaborate morphologies during the late Pliocene-Pleistocene? Ocean Drilling Program (ODP) Site 1115 (Woodlark Basin, Papua New Guinea) provides an opportunity to address the biostratigraphic record and morphological evolution of G. fistulosus at high-resolution. The cores across the Pliocene-Pleistocene interval have excellent recovery, with abundant, well preserved planktonic foraminifera and high sedimentation rates. In addition, the cores also yield calcareous nannofossils (from which an initial biostratigraphy has been established; Shipboard Scientific Party 1999); and a magnetostratigraphy has also been interpreted from initial ODP palaeomagnetic measurements. This additional stratigraphic data will supplement the preliminary results


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of this study, aiding with refining the biochronology for the late Pliocene-Pleistocene. The newly established record will be contrasted with different ocean basins in order to assess potential LAD diachrony for G. fistulosus.

Figure 1. Scanning Electron Microscope (SEM) image of the morphologically diverse Globigerinoides fistulosus, highlighting the typical ‘finger-like projections’ which often produce a hand-shaped test. Image source: Worldwide Web Address; www.bgr.bund.de (Federal Institute for Geosciences and Natural Resources, Hannover, Germany).

Chaisson, W. P. & D'Hondt, S. L. 2000. Neogene planktonic foraminifer biostratigraphy at Site 999, Western Caribbean Sea. In:

Leckie, R. M., Sigurdsson, H., Acton, G. D. & Draper, G. et al. (Eds), Proceedings of the Ocean Drilling Program, Scientific Results, 165, 19-56.

Chaisson, W. P. & Leckie, R. M. 1993. High-Resolution Planktonic Foraminifer Biostratigraphy of Site 806, Ontong Java Plateau (Western Equatorial Pacific). In: Berger, W. H., Kroenke, L. W., Mayer, L. A. et al. (Eds), Proceedings of the Ocean Drilling Program, Scientific Results, 130, 137-178.

Chaisson, W. P. & Pearson, P. N. 1997. Planktonic foraminifer biostratigraphy at Site 925: middle Miocene–Pleistocene. In: Shackleton, N. J., Curry, W. B., Richter, C., Bralower, T. J. et al. (Eds) Proceedings of the Ocean Drilling Program, Scientific Results, 154, 3-32.

Kennett, J. P. & Srinivasan, M. S. 1983. Neogene Planktonic Foraminifera, A Phylogenetic Atlas. Hutchinson Ross, Stroudsburg, Pennsylvania. 265pp.

Parker, F. L. 1967. Late Tertiary biostratigraphy (planktonic Foraminifera) of tropical Indo-Pacific deep-sea cores. Bulletin of American Paleontology, 52, 115-203.

Shipboard Scientific Party. 1999. Site 1115. In: Taylor, B., Huchon, P., Klaus, A., et al. (Eds), Proceedings of the Ocean Drilling Program, Initial Reports, 180, 1-226.

Sinha, D. K. & Singh, A. K. 2008. Late Neogene planktic foraminiferal biochronology of the ODP Site 763A, Exmouth Plateau, southeast Indian Ocean. Journal of Foraminiferal Research, 38, 251-270.

Ostracodes and Plate Tectonics: A Case from the latest Cretaceous of the Caribbean Region T. Markham Puckett [email protected] Department of Physics and Earth Science P.O. Box 5130 University of North Alabama Florence, AL 35632-0001 One of the greatest uses of ostracodes is for paleobiogeography. It is well known that the distribution of some ostracode taxa is strongly controlled by geography. This is mainly because some shallow marine ostracodes cannot cross deep water barriers, even across relatively short geographic distances (Babinot and Colin 1988, Babinot and Colin 1992, Seeling et al., 2002). The provincial distribution of the shallow marine ostracodes offers opportunities to study two kinds of problems: plate tectonic and evolutionary/taxonomic. For example, if there are areas now separated by deep water that contain the same coeval, shallow marine species or genera, it suggests the possibility that the areas were together at one time and have since rifted apart. Alternately, if there are geologic terranes in a single landmass that contain different ostracode taxa, it suggests the possibility that the ostracodes evolved on different terranes that have since accreted. The other use is in the fields of evolution, systematics and taxonomy. If faunal barriers can be delineated when studying the paleobiogeographic distribution of ostracodes, then that narrows our search for ancestor-descendent relations, which can be used to more accurately recognize genera.


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Twenty-four new species and three new genera of Late Cretaceous (Maastrichtian) marine ostracodes were recently described from Jamaica (Puckett, in press). Thirty-five samples were collected from five Cretaceous inliers, which include the central, northern and western parts of the island. The best preserved specimens were collected from the Guinea Corn Formation of the Central Inlier. These twenty-four new species were recognized out of thirty-two identified taxa, indicating a high degree of endemism. Whereas some ostracode taxa, such as the genera Cytherella, Bairdia, Krithe and Paracypris, are nearly ubiquitous, many ornamented taxa lived only in shallow water; for these taxa, deep water was a barrier to migration, thus resulting in provincial distributions. The purpose of this study was to determine endemism of the ostracode faunas and its relation to the geologic evolution of the Caribbean region. Ostracodes collected from the Ocozocoautla Formation (Maastrichtian) of Mexico are similar to those of Jamaica, although the poor preservation of the Mexican samples makes determination uncertain at the species level. Common shallow-water taxa occurring in both Jamaica and Mexico include species of Buntonia and Ayselgulina and the new genus Spinicytheridea. None of these genera occur in coeval deposits of North America, whereas many genera of North America, including Fissocarinocythere, Antibythocypris, Ascetoleberis, and Bicornicythereis, among many others, do not occur outside of the North American Gulf Coastal Plain. Paleobiogeographically, these distributions indicate that ostracode faunas in Jamaica and Mexico were in good genetic communication, but communication with those of North America was more tenuous. This observation indicates that, during the Late Cretaceous, Jamaica was close to Mexico, if not in shallow-water continuity. Translation of Jamaica from Mexican proximity to its present relative position was accomplished by a well-known mechanism: movement along the Cayman Trough. Complex left-lateral movement and spreading in the Cayman structure initiated during the Eocene and has translated Jamaica approximately 1500 kilometers to its present relative position. Babinot, J-F., and Colin, J-P., 1988. Paleobiogeography of Tethyan Cretaceous marine ostracods. In: HANAI, T., IKEYA, N. and

ISHIKAZI, K. Eds. Evolutionary Biology of Ostracoda, Its Fundamental and Applications: Proceedings of the Ninth International Symposium on Ostracoda. Amsterdam and Tokyo: Elsevier Scientific Publishing Co., and Kodansha: 823-839.

Babinot, J-F., and Colin, J-P , 1992. Marine ostracode provincialism in the Late Cretaceous of the Tethyan realm and the Austral Province. Palaeogeography, Palaeoclimatology, Palaeoecology, 92:283-293.

Puckett, T., Markham, Colin, J-P., and Mitchell, S., in press, New species and genera of Ostracoda from the Maastrichtian (Late Cretaceous) of Jamaica: Micropaleontology, v. 58, no. 5.

Seeling, J., Colin, J.-P. and Fauth, G. 2004. Global Campanian (Upper Cretaceous) ostracod palaeobiogeography. Palaeogeography, Palaeoclimatology, Palaeoecology, 213:379-398.

Upper Cretaceous Radiolarian Assemblages and Paleoenvironments of the Sverdrup Basin, Ellef Ringnes Island, Nunuvut, Canada A. T. Pugh1, C. J. Schröder-Adams1, E. S. Carter2, J. O. Herrle3, J. W. Haggart4, and J. M. Galloway5

1Dept. of Earth Sciences, Carleton University, Ottawa, Ontario, Canada, K1S 5B6, [email protected]; 2Dept. of Geology, Portland State University, Portland, Oregon, 97207-0751, USA, 3Institute of Geosciences, Goethe University, 60438 Frankfurt, Germany; 4Geological Survey of Canada, Vancouver, British Columbia, V6B 5J3, Canada; 5Geological Survey of Canada, Calgary, T2L 2A7, Canada A late Albian to Campanian sedimentary record on Ellef Ringnes Island, Canadian Arctic Archipelago, records variable paleoenvironmental conditions within the Cretaceous Boreal Sea and Sverdrup Basin. The upper Albian to lower Cenomanian uppermost Christopher and Hassel formations represent a regressive system tract from offshore to shoreface and terrestrial paleoenvironments. The upper Cenomanian to Campanian shales of the Kanguk Formation signify a distal central basin setting controlled by increased subsidence and high global sea levels. Siliceous pelagic faunas and floras dominate the basin and herein, a new radiolarian zonation for the Boreal Sea is proposed. Alternating diversity and abundance patterns are interpreted as a response to sea-level controlled productivity systems. Transgressive phases correspond to low diversity shallow dwelling radiolarian taxa (Spumellaria) with an expanded Oxygen Minimum Zone (OMZ); regressive and lowstand phases are coupled with radiolarian radiations of deeper dwelling species (Nassellaria) and a depressed OMZ. The late Cenomanian to Coniacian is marked by increased preservation of marine-type organic matter, whereas the terrestrial influence is prevalent during the late Coniacian to Campanian. These intervals are then further correlated to the diversity and abundance patterns reflected in the radiolarian biostratigraphy, allowing for further subdivision of the Kanguk Formation. Benthic environments are dominated by anoxic conditions, as suggested by the lack of benthic fauna. Only the Santonian records a return to dysoxic benthic conditions. Radiolarian faunal comparisons to more southern localities suggest migration routes from the east through narrow North Atlantic pathways and from the Pacific realms through the Alaskan-Asian Pathway.


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Biozonation and Biochronology of Cenozoic Calcareous Nannofossils from Low and Middle Latitudes Isabella Raffi1, Jan Backman2, Domenico Rio3, Claudia Agnini3, Eliana Fornaciari3, and Heiko Pälike4 1Dipartimento di Ingegneria e Geologia (InGeo) – CeRSGeo, Università degli Studi “G. dʼAnnunzio” Chieti-Pescara, via dei Vestini 31, 66013 Chieti-Pescara, Italy, [email protected] 2Department of Geological Sciences, Stockholm University, SE-106 91 Stockholm, Sweden. 3Dipartimento di Geoscienze, Università degli Studi di Padova, via G. Gradenigo 6, 35131 Padova, Italy. 4 Center for Marine Environmental Sciences (MARUM), Bremen University, Leobener 8 Strasse, Bremen, 28359, Germany. Calcareous nannofossils are widely used for biostratigraphic classification and age assignement of Cenozoic marine sediments. The two most widely used calcareous nannofossil biozonations were established approximately 40 years ago and are the result of the pioneering works of Erlend Martini and David Bukry, based on studies on marine land sections and Deep Sea Drilling Project rotary-cored sediments. Here we present a new biozonation that incorporates updated biostratigraphic data and methodologies within the known biostratigraphic framework of Martini and Bukry (Martini, 1971; Bukry,1973,1978; Okada and Bukry, 1980). This zonation is derived from biostratigraphic data we generated over nearly three decades, studying calcareous nannofossils in Paleocene through Pleistocene marine land sections and deep-sea sediments in low and middle latitude regions. Our work had and continues to have the aim to pursue a detailed calcareous nannofossil biostratigraphy through the use of semi-quantitative methods in combination with short sample distances. The sampling resolution should be close enough to capture the details of the abundance behavior of individual calcareous nannofossil taxa. A key feature of our biozonation is the use of a limited set of selected biohorizons for the purpose of establishing a relatively coarsely resolved and stable biozonation. A single biohorizon is used for the definition of each biozone boundary. Subzones and auxiliary markers are avoided, in order to maintain stability to the new biozonation. We use a new code system that implies a code letters for each series and a number for each biozone. The “Neogene portion” of our Biozonation has been recently published (Backman et al., 2012). In the interval Miocene through Pleistocene, we presented 31 Biozones: Calcareous Nannofossil Miocene biozones 1 through 20, CNM1 - CNM20, and Calcareous Nannofossil Plio-Pleistocene biozones 1 through 11, CNPL1 - CNPL11. The “Paleogene portion” comprises 36 Biozones: Calcareous Nannofossil Paleocene biozones 1 through 11, CNP1 - CNP11; Calcareous Nannofossil Eocene biozones 1 through 19, CNE1 - CNE19; Calcareous Nannofossil Oligocene biozones 1 through 6, CNO1 - CNO6. The average biostratigraphic resolution is: 0.74 million years in the Miocene-Pleistocene, with biozone duration ranging from 0.15 to 2.20 m.yrs; 0.9 million years in the Paleocene, with biozone duration ranging from 0.43 to 2.04 m.yrs; ~1 million years in the Eocene, with biozone duration ranging from 0.33 to ~2.1 m.yrs; 1.9 million years in the Oligocene, with biozone duration ranging from 0.9 to 3.07 m.yrs. We assigned age estimates to all biozone boundary markers and to several additional biohorizons, and specified the position of the biohorizons with respect to paleomagnetic chrons. Age assignments derive from astronomically tuned cyclostratigraphies in the time interval from 0 to ~41 Ma and from GPTS of Cande and Kent (1995) in the time interval from ~41 to 65 Ma (to the K/Pg boundary). Backman, J., Raffi, I., Rio, D., Fornaciari, E., Pälike, H., 2012. Biozonation and biochronology of Miocene through Pleistocene

calcareous nannofossils from low and middle latitudes. Newsletters on Stratigraphy, 45, 221-244, doi: 10.1127/0078-0421/2012/0022.

Bukry, D., 1973a. Low–latitude coccolith biostratigraphic zonation. In: Edgar, N.T., Saunders, J.B., et al., Initial Reports DSDP 15, Washington (U.S. Govt. Printing Office), 685−703. doi:10.2973/dsdp.proc.15.116.1973.

Bukry, D., 1978. Biostratigraphy of Cenozoic marine sediments by calcareous nannofossils. Micropaleontology 24, 44–60. Martini, E., 1971. Standard Tertiary and Quaternary calcareous nannoplankton zonation. In: Farinacci, A. (Ed.), Proceedings 2nd

International Conference Planktonic Microfossils Roma: Rome (Ed. Tecnosci.) 2, 739−785. Okada, H., and Bukry, D., 1980. Supplementary modification and introduction of code numbers to the low–latitude coccolith

biostratigraphic zonation (Bukry, 1973; 1975). Marine Micropaleontology 5, 321−325. Foraminiferal Biostratigraphy Helps Understanding of the Evolution of a Quaternary Deep-Water Lobe Complex in Campos Basin Brazil Aristóteles de Moraes Rios-Netto1, Daniela Santos Machado Brito2, Fernanda Silva de Araújo2, Carlos Jorge Abreu3

1Laboratório de Bioestratigrafia e Paleoecologia – LabMicro, Departamento de Geologia, Universidade Federal do Rio de Janeiro – UFRJ, Rio de Janeiro (RJ), Brasil. E-mail: [email protected]


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2Laboratório de Bioestratigrafia e Paleoecologia – LabMicro, Departamento de Geologia, Universidade Federal do Rio de Janeiro – UFRJ, Rio de Janeiro (RJ), Brasil. 3Universidade de Brasília – UnB, Instituto de Geociências, Brasília (DF), Brasil.

Aiming to use Quaternary deposits as analogues to the Oligocene turbiditic reservoirs of Campos Basin, Abreu et al. (2004) and Abreu (2005) studied a geomorphologic feature located in the Southeastern Brazilian continental slope which, until then, was known as Almirante Câmara Submarine Fan. Based on 2D and 3D seismic lines, those authors concluded that this feature was not homogeneuos, since it was actually composed by five lobes, and renamed it Almirante Câmara Lobe Complex (ACLC). Abreu (2005) also subdivided the uppermost lobe (Lobe 5) in 9 sublobes. The goal of the present work is the understanding of the evolution of those sublobes, based on the foraminiferal biostratigraphic analyses and interpretation of five piston cores. The studied piston-cores are from 1,06 to 1,54 meters long each, and were colected in the sublobe 5 of the ACLC, under 2,295 to 2,320 meters water depth. The biostratigraphic analyses lead to recognizing of the biozones Z and Y of Ericson & Wollin (1968), and the Subzone Y1 of Vicalvi (1999), which corresponds to the upper part of the Biozone Y of Ericson & Wollin (op.cit.). Integration of bioestratigraphic results and litologic data showed the presence of three discrete sand pulses: the first one occurs in the piston-cores LAC-02, LAC-07 and LAC-08, in the uppermost Subzone Y1; the second pulse was recognized in the piston-core LAC-05, in the lower part of the Zone Z, bellow an oxidized interval earlier described by Vianna (1998) in the same area of Campos Basin; the third sand pulse, which occurs only in the piston-core LAC-07, has eroded the upper part of the Zone Z, above the oxidized interval. Recognizing of these discrete sand pulses showed that the sublobes identified by Abreu et al. (2004) e Abreu (2005) were formed by distinct and successive sand fluxes– they do not corresponds to single events. These results were also integrated with the interpretation of seismic lines proceed by Abreu (2005), allowing the correlation of the spacial distribution of those sand pulses to the presence of submarine channels on the ACLC. Abreu, C.J. 2005. Complexo de Lobos do Sistema Deposicional Moderno de Águas Profundas Almirante Câmara Imageado por

Sísmica de Alta Resolução, Bacia de Campos. Programa de Pós-graduação em Geologia, Universidade Federal do Rio de Janeiro, D.Sc. Thesis, 132p.

Abreu, C. J.; Appi, C. J.; Silva, F. G.; Matos, R. S. 2004. Arquitetura deposicional de um complexo de lobos turbidíticos modernos de águas profundas, bacia de Campos, através do imageamento sísmico de alta resolução. In: CONGRESSO BRASILEIRO DE GEOLOGIA, 42., 2004, Araxá,MG. [Trabalhos apresentados]... São Paulo: Sociedade Brasileira de Geologia, 2004. 1 page, arquivo 32_1235_ABREUCJ.pdf.

Ericson, D.B.; Wollin, G. 1968. Pleistocene climates and chronology in deep-sea sediments. Sciences, v.162, p.1227-1234. Viana, A.R. 1998. Le rôle et l’enregistrement des courants oceaniques dans les depots de marges continentales: la marge du

bassin Sud-Est Bresilien. Université de Bordeaux I, France, Ph.D. Thesis, 364p. Vicalvi, M.A. 1999. Zoneamento Bioestratigráfico e Paleoclimático do Quaternário Superior do Talude da Bacia de Campos e Platô

de São Paulo Adjacente, com Base em Foraminíferos Planctônicos. 184p. (Programa de Pós-graduação em Geociências/ Universidade Federal do Rio de Janeiro, D.Sc. Thesis).

The Palynological Record of South Africa’s Permian Coal Deposits: Clue to Decipher Gondwana’s Climate History on High Time Resolution Katrin Ruckwied1 and Annette E. Götz2 1Shell International Exploration and Production, 200 North Dairy Ashford, Houston, Texas 77079, USA; [email protected]

2Department of Geology, Rhodes University, Grahamstown 6140, P.O. Box 94, South Africa The Permian coal-bearing formations of the South African Karoo Basin play a crucial role in the study and interpretation of Gondwana's climate history and biodiversity in this time of major global changes in terrestrial and marine ecosystems. The coal fields of the NE Karoo sub-basins contain high volatile bituminous coals of low maturity with a vitrinite reflectance ranging from 0.62% to 0.8% and thus yield well-preserved palynomorph assemblages. Here, we report on new palynological data from the No. 2 coal seam of the northern Witbank coal field, documenting the switch from Icehouse to Greenhouse conditions in the Early Permian (Lower Ecca Group). The studied postglacial fluvio-deltaic deposits of a highly proximal setting comprise coarse-grained to pebbly sandstones, partially with an abrupt upward transition into fine-grained sediments and coal, trough cross-stratified medium- to coarse-grained sandstones, and horizontally laminated fine- to medium-grained sandstones and siltstones. The sedimentary organic matter content clearly documents stratal changes in the palynomorph assemblage and variations in the amount and in the type, size and shape of plant debris. Generally, palynofacies is characterized by a high amount of opaque phytoclasts. Amorphous organic matter is characteristic of laminated siltstones and coals. The palynological record indicates a cold climate, fern wetland community, characteristic of lowland alluvial plains, and an upland


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conifer community in the lower part of the coal seam. Up section, these communities are replaced by a cool-temperate cycad-like lowland vegetation and gymnospermous upland flora. Ongoing studies focus on the cyclic architecture of the coal seam, applying palynofacies analysis as high-resolution correlation tool with respect to decipher signatures of prominent climate amelioration on basin-wide, intercontinental and intra-Gondwanic scales. Enhanced Calcareous Nannoplankton Productivity during the Middle Miocene Transition in the Eastern Equatorial Pacific (IODP Site U1338) Leah J. Schneidera1*, Timothy J. Bralowera, Lee R. Kumpa, Ann Holbournb, and Oscar E. Romeroc a Department of Geosciences, The Pennsylvania State University, 503 Deike Building, University Park, PA 16802, USA b Institute of Geosciences, Christian-Albrechts-University, Ludewig-Meyn-Str. 14, D-24118 Kiel, Germany

c Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Ave. de las Palmeras 4, ES-18100, Granada, Spain 1 Present address: Integrated Ocean Drilling Program, Texas A&M University, 1000 Discovery Drive, College Station, TX 77845, USA * [email protected] The middle Miocene climate transition (MMT) at 13.9 Ma is the final shift from a greenhouse climate into a modern-day-like ocean-atmospheric system with cold high latitudes and a strong meridional temperature gradient. The event is marked by the major expansion of the East Antarctic ice sheet (EAIS; Mi-3) as indicated by a 1‰ increase in δ18O values. The MMT is tied to enhanced bottom water formation and the cooling of high latitude regions; however, little is known about its effect on low latitude climate and oceanography. To determine if low latitudes were affected and if the glaciation influenced equatorial upwelling, we examined the calcareous nannoplankton assemblage, opal weight %, and grain size of sediments from IODP Site U1338 in the eastern equatorial Pacific (EEP). These records are compared to the benthic isotope record to determine the timing of the MMT and carbon isotope maximum 6 (CM6) of the Monterey isotope excursion. Our results show a shift in the nannoplankton assemblage associated with the MMT and during CM6. At the MMT, warmer-water, oligotrophic taxa decrease in abundance and are replaced by cooler-water taxa. During CM6, which is coincident with the maximum in Antarctic glaciation, there is a significant increase in small Dictyococcites species (< 3 µm) that have a bloom-like appearance. In the modern ocean this assemblage is indicative of high nannoplankton productivity. In addition, sedimentation rates increase during the first half of the glacial interval. Siliceous plankton are absent from the glaciation interval and were unable to inhabit the EEP during this time possibly due to nutrient limitation. The EEP responded to high latitude forcing as evidenced by the nannoplankton assemblage. These results can help us to better understand the linkage between high latitude forcing and equatorial upwelling dynamics and intensity. Contrasting Paleoenvironments and Paleoproductivity Signals in the Upper Cretaceous Boreal Sea: A Multi-Fossil Approach C.J. Schröder-Adams1, A.T. Pugh1, J. Andrews1, J. O. Herrle2, J. W. Haggart3, M. Hay4, D. Harwood5 and J.M. Galloway6 1Dept. of Earth Sciences, Carleton University, Ottawa, Ontario, Canada, K1S 5B6, [email protected]; 2Institute of Geosciences, Biodiversity and Climate Research Centre (BIK-F), Goethe University Frankfurt, D-60438 Frankfurt am Main, Germany; 3Geological Survey of Canada, Vancouver, British Columbia, V6B 5J3, Canada; 4Département des Sciences humaines,Université du Québec, Chicoutimi, Québec, G7H 2B1 Canada; 5Dept. of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Nebraska, 68588-0340, USA; 6Geological Survey of Canada, Calgary, T2L 2A7, Canada. The Cretaceous Boreal marine system is not well understood and the resolution is hindered by taphonomic loss of proxies such as the solubility of biogenic silica under deep burial and carbonate dissolution as the result of acidic porewater. The Late Cretaceous Arctic Ocean experienced ice-free summers that resulted in high surface productivity dominated by biogenic siliceous microfossils and dinoflagellates. The Cenomanian to Campanian Kanguk Formation of Arctic Canada remains an undivided thick shale package lacking a biostratigraphic framework. This study uses a multi-fossil approach to impose stage boundaries and to contrast the Kanguk Formation and its depositional and paleoecological history as exposed on Ellef Ringnes Island with equivalent strata on Axel Heiberg Island, both part of the Queen Elizabeth Islands.


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The Ellef Ringnes locality represents a central location in Sverdrup Basin during Kanguk deposition and is a bio-silica dominated system. In contrast, the Kanguk Formation as exposed on Axel Heiberg shows no bio-silica preservation. High surface productivity is evidenced at Ellef Ringnes by diatoms and radiolaria in addition to abundant dinocycts. The mix of plankton and mud and silt suggests winter sea-ice, whereas the lack of coarser clastics excludes glacial ice and floating ice as sediment transport mechanisms. Microfossil assemblages respond to transgressive/regressive sea-level phases linking the Boreal Sea to eustatic cycles. Regressions triggered radiations in radiolarian and dinocyct assemblages due to reduced oxygen minimum zones (OMZ) and fertile shelf settings. Transgressive phases provided increased rates of organic matter deposition, in part due to terrestrial flooding coupled with humid conditions and input of Type III organic matter, but also high surface productivity (type II organic matter) which resulted in an expanded OMZ. These systems are prevalent throughout the late Cenomanian to Coniacian. As temperature cooled again primary productivity and carbon flux decreased and slight bottom oxygenation returned in the upper Santonian, where rare benthic foraminifera are observed. No carbonate is preserved in this system. In contrast, at Glacier Fiord, Axel Heiberg Island, the Kanguk Formation is interpreted as an outer shelf setting within the Sverdrup Basin and therefore is more proximal than the Ellef Ringnes locality. The most distal part of this section is represented by the uppermost Cenomanian/lower Turonian interval that is characterized by the newly established OAE 2 interval in the Sverdrup Basin, which provides a reliable marker for correlation to the Ellef Ringnes section. Bottom hypoxia developed during that time and benthic foraminifera are absent in thinly bedded ‘paper shale’. Biogenic silica is absent either due to high suspended sediment turbidity and therefore a limited photic zone or not preserved due to deep burial. As sea level fell during the late Turonian, the proximal setting of this locality was increasingly oxygenated, and capable of supporting abundant and diverse benthic foraminiferal communities from the late Turonian to Campanian. A late Santonian to early Campanian shelf setting at the top of the section is supported by communities of large Inoceramus shells inhabiting the sea floor. Whereas upwelling processes might have played a role at the distal setting of Ellef Ringnes, stratification did not develop in this region, with the exception of the OAE 2 interval. Comparison of Three Preservation Techniques for Slowing Dissolution of Calcareous Nannofossils in Organic-Rich Sediments Ellen L. Seefelt *, Jean M. Self-Trail, and Arthur P. Schultz U.S. Geological Survey, *[email protected] Rapid dissolution of calcareous nannofossils from organic and/or pyrite-rich sediments previously has been documented from Atlantic Coastal Plain sediments (Self-Trail & Seefelt, 2005). Minor amounts of dissolution have been recorded from carbonate-rich deep-sea sediments (Dunkly Jones & Bown, 20067). In an effort to identify a storage system that will halt or slow down dissolution of calcareous nannofossils in organic and/or pyrite-rich sediments, three different methods of short-term storage of calcareous nannofossil bearing sediments were tested. Samples from three cores were chosen for their contrasts in sediment type: siliciclastic marine clays and silts from Cambridge-Dorchester (Cam-Dor, MD), glauconitic, pyritic, and siliciclastic sediments from Dixon (NC), and carbonate-rich packstones and wackestones from Pineora (GA). Each core was systematically sampled on the day of coring, and an onsite smear slide (a) was immediately prepared. Each sample was then split in two; one split was used to prepare control slides at one-month (b1) and six-month (c1) intervals, and the other split was used to test storage methods. Storage samples were placed either in vacuum-packed bags, in vials filled with argon gas, or in vials filled with buffered water in order to neutralize pH. They were sampled at one-month (b2) and six-month (c2) intervals for comparison with the control slides. All slides were examined using a Zeiss Axioplan 2 light microscope at 1250x magnification. Abundance counts of total calcareous nannofossils per 150 fields of view (FOV) were tallied for each slide. The decrease in calcareous nannofossil percent abundance was calculated over six months, and storage samples were directly compared to control samples. Counts showed that none of the three methods were consistently effective in reducing loss due to dissolution (fig. 1). In most cases, the control (a) slides had the best retention of calcareous nannofossils. Although vacuum packed, argon gas, and buffered water samples produced some positive results, the overall decrease of nannofossil abundances suggests that trapped oxygen in sediment pore spaces continued to react with pyrite and organics to drive dissolution. Calcium-carbonate rich sediments in the Pineora core also experienced loss from dissolution, possibly due to the presence of diagenetic pyrite. Dunkley Jones, T., and Bown, P.R., 2007, Post-sampling dissolution and the consistency of nannofossil diversity measures: A case

study from freshly cored sediments of coastal Tanzania: Marine Micropaleontology, v. 62, p. 254- 268. Self-Trail, J.M., and Seefelt, E.L., 2005, Rapid dissolution of calcareous nannofossils: a case study from freshly cored sediments of

the south-eastern Atlantic Coastal Plain: Journal of Nannoplankton Research, v. 27, n. 2, p. 149-157.


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Palynological Analysis of the Terrestrial Deposits of the Ravenscar Group (Middle Jurassic), Northeast Yorkshire, UK Sam Slater1 and Charles Wellman2

1University of Sheffield, United Kingdom, [email protected] 2University of Sheffield, United Kingdom Palynomorphs from Middle Jurassic terrestrial deposits of the Ravenscar Group from the Cleveland Basin in northeast Yorkshire are used to reconstruct the palaeoenvironmental conditions at this time. The assemblage provides new insight into the underrepresented plant record through the Middle Jurassic. Assemblages of abundant, diverse and well preserved spores/pollen have been recovered from numerous horizons throughout the sequence. Palynological samples have been spiked with Lycopodium tablets to determine absolute abundances. Megaspores are found present from the Bathonian Long Nab member of the Scalby Formation. Preservation of megaspores is outstanding and in three-dimensions. Combined analysis using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) reveals the presence of at least three species (Paxillitriletes phyllicus, Minerisporites institus and Reticuspinosporites ravenscarensis gen. et sp. nov.) of lycopsid affinity. The lycopsid affinity of R. ravenscarensis gen. et sp. nov. is based on the wall ultrastructure from TEM analysis. TEM analysis of R. ravenscarensis gen. et sp. nov. shows the presence of three wall layers: an outer layer covering the ornaments (outer exospore); a thick spongy layer (middle exospore); and a thin inner layer comprised of numerous lamellae (inner exospore).

Palaeogeographic reconstructions show upland areas surrounding the coastal plain setting of the inner Cleveland Basin were dominated by coniferous forests whilst the lowland areas were characterised by low-standing vegetation types including sphenotypes and pteridophytes. The assemblage indicates a warm-temperate climate with distinct monsoonal wet and dry seasons. Palaeoenvironmental reconstructions indicate deltaic and fluvial conditions with intermittent marine incursions in the Aalenian and lower Bajocian.


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On the Phylogeny of Paleogene Planktonic Foraminifera: Wall Texture Structure and a New Genus Name for the broedermanni Lineage Dario M. Soldan, Maria Rose Petrizzo, Isabella Premoli Silva Dipartimento di Scienze della Terra “A. Desio”, Università degli Studi di Milano, via Mangiagalli 34, 20133 Milano, Italy; [email protected] The broedermanni lineage has been traditionally placed in the genus Igorina (see Berggren and others, 2006) being characterized by possessing a biconvex globorotaliid morphology, subglobular to subquadrate chambers, and by having a nonspinose wall texture with thin muricae on the test surface. Our analysis of specimens from the Pacific Ocean (ODP Leg 198, Shatsky Rise and ODP Leg 143, Alllison Guyot) suggest that the broedermanni group is phylogenetically related to Acarinina as the calcite structures of the wall are similar to the muricae rather than to the short pustules of the Paleocene igorinids (i. e., I. pusilla, I. albeari). In particular, the oldest species lodoensis shows a typical coarse muricate test similar to Acarinina while in its descendants, broedermanni and anapetes, the muricae are finer on the spiral side, and heavier muricae are developed only around the umbilicus. Moreover, in the broedermanni group the shell is not encrusted as in Igorina because the pustules remained isolated and increased in size to become thick muricae. The analysis of the pore structure in cross section seems to confirm the similarities and affinities between the wall texture of the broedermanni group and Acarinina. Both show an hourglass shape of the pores that become narrow in the outer calcite layer whereas in Igorina species the pores are tight in the inner calcite layer. In addition, the results from parsimony analysis (Soldan and other, 2011) confirm that the broedermanni group evolved in the late Paleocene/early Eocene from the group of round acarininids (A. mckannai and A. soldadoensis). The new genus Pearsonites (named in honor of Professor Paul N. Pearson) with Pearsonites broedermanni as type species,is here proposed to accommodate the early-middle Eocene globorotaliid taxa of the broedermanni lineage with a wall texture bearing muricae. Three species previously considered morphologically and evolutionary related to the Paleocene genus Igorina are here included in Pearsonites nov. gen., P. lodoensis, P. broedermanni, and P. anapetes. Species assigned to Pearsonites nov. gen. are relatively common in the stratigraphic interval from the upper Paleocene (Zone P5) to the middle Eocene (Zone E9). Berggren W.A., Pearson P.N., Huber B.T., Wade B.S., 2006. Chapter 19: Taxonomy, biostratigraphy and phylogenetic affinities of

Eocene Acarinina, in Pearson P. N., Olsson R.K, Huber B.T., Hemleben C., Berggren W.A (eds), Atlas of Eocene Planktonic Foraminifera: Cushman Foundation Special Pubblication, v. 41, p. 257-326.

Soldan D.M., Petrizzo M.R., Premoli Silva I., Cau A., 2011. Phylogenetic relationships and evolutionary history of the Paleogene genus Igorina through parsimony analysis: Journal of Foraminiferal Research, v. 41, p. 260-284.

Depositional Environment of the Lower Hell Creek Formation: Evidence from Lithology and Palynoflora Marissa K. Spencera, Francisca E. Oboh-Ikuenobea, Carl E. Campbellb , Stephanie E. Kusterc, Ashley Olsond

a Missouri University of Science and Technology, Department of Geological Sciences and Engineering, 129 McNutt Hall, Rolla, MO 65409-0410, USA, [email protected]; b Saint Louis Community College-Meramec, Saint Louis, MO 63122, USA; c St. Louis Science Center, 5050 Oakland Avenue, Saint Louis, MO 63139; d701 Stephen Moody St. SE, Apt. 414, Albuquerque, NM 87123, USA The Hell Creek Formation has long interested scientists because it spans an interval of approximately three million years culminating in the Cretaceous/Paleogene extinction event 65.5 million years ago (Hartman et al., 2002; Nichols and Johnson, 2008). The formation is well known for yielding abundant remains of several types of dinosaurs, including ceratopsians and tyrannosaurs (Russell and Manabe, 2002; Horner et al., 2011; Gates et al., 2010; Butler and Barrett, 2008; Lehman, 1987). Although palynology has long played a key role in constraining the biostratigraphy of the formation (Hartman et al., 2002; Bercovici et al., 2009), few studies have focused on the paleoenvironmental relationship between palynofloras and specific dinosaur remains. A multidisciplinary research project integrating lithology, stratigraphy, vertebrate paleontology (dinosaurs) and palynology (dispersed organic matter and palynomorphs) targets two stratigraphic trenches and associated bone beds in the lower Hell Creek Formation in Garfield County, Montana where dinosaur fossil bones of Triceratops, Torosaurus and Tyrannosaurus rex have been recovered (Campbell et al., 2007). This study focuses on the lithological and palynological components of the project. The basal deposit of the lower Hell Creek is a channel-sandstone that is incised into the Fox Hills Formation. Above this sandstone, the sediments comprise alternating layers of sandstone, siltstone, mudstone, and organic-rich silt and clay. Occasional plant fragments and root traces are present.


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Twenty-six samples, including three from the underclay and matrix of a Triceratops femur, were processed for palynology following the technique described by Traverse (2007). Comminuted phytoclasts are the most abundant (>80%) dispersed organic matter components, which also include variable abundances of structured and degraded phytoclasts, opaque clasts, sporomorphs, and fungal remains. A diverse palynomorph assemblage belonging to the Late Cretaceous Wodehousia spinata Assemblage Zone (Nichols, 1994) is present. Key sporomorphs include various species of Aquipollenites, Cranwiella rumseyensis, Erdtmanipollis cretaceous, Taxodiaceaepollenites hiatus, and Wodehousia spinata. The palynomorph assemblage also includes the freshwater colonial green algae Botryococcus and Pediastrum, as well as spores of Azolla and Ghoshispora. The large numbers of conifer pollen recovered in the samples, in particular Pityosporites, may be indicative of dietary preference for Triceratops (Chin and Gill, 1996). This study suggests that warm temperate to subtropical conditions existed during the deposition of the fluvial sediments of the lower Hell Creek. The inferred paleovegetation is indicative of a diverse group of plants consisting of ferns, cycads, conifers, palms, vines, and aquatic plants that likely provided abundant food and cover for a variety of animals including the dinosaurs. Bercovici, A., Pearson, D., Nichols, D., and Wood, J., 2009. Biostratigraphy of selected K/T boundary sections in southwestern

North Dakota, USA: towards a refinement of palynological identification criteria. Cretaceous Research, vol. 30, p. 632-658. Campbell, C.E., Novak, S.E., and Kern, J.M., 2007.Tyrannosaurus and Triceratops in Lower Hell Creek bone bed. Geological

Society of America Abstracts with Programs, vol. 39, No. 6, p. 418 (Paper No. 153-12). Chin, K. and Gill, B.D. 1996. Dinosaurs, dung beetles, and conifers: participants in a Cretaceous food web. Palaios, vol. 11, p. 280–

285. Gates, T.A., Sampson, S.D., Zanno, L.E., Roberts, E.M., Eaton, J.G., Nydam, R.L., Hutchison, J.H., Smith, J.A., Loewen, M.A., and

Getty, M.A., 2010. Biogeography of terrestrial and freshwater vertebrates from the late Cretaceous (Campanian) Western Interior of North America. Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 291, p. 371–387.

Horner, J.R., Goodwin, M.B., and Myhrvold, N., 2011. Dinosaur census reveals abundant Tyrannosaurus and rare ontogenetic stages in the Upper Cretaceous Hell Creek Formation (Maastrichtian), Montana, USA. PLoS ONE, vol. 6 (2), e16574.

Lehman, T.M. 1987. Late Maastrichtian paleoenvironments and dinosaur biogeography in the western interior of North America. Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 60, p. 189–217.

Nichols, D.J., 1994. A revised palynostratigraphic zonation of the nonmarine Upper Cretaceous, Rocky Mountain region, United States, In: Caputo, M.V., Peterson, J.A. and Franczk, K.J., eds., Mesozoic Systems of the Rocky Mountain Region, USA. Rocky Mountain Section, Society for Sedimentary Geology, p. 503-521.

Hartman, J.H., Johnson, K.R., and Nichols, D.J., eds, 2002. The Hell Creek Formation and the Cretaceous-Tertiary Boundary in the Great Plains: An Integrated Continental Record of the End of the Cretaceous. The Geological Society of America Special Paper 361, 520 p.

Nichols, D.J., and Johnson, K.R., 2008. Plants and the K-T boundary. Cambridge University Press, Cambridge, UK, 292 p. Russell, D.A., and Manabe, M., 2002. Synopsis of the Hell Creek (uppermost Cretaceous) dinosaur assemblage. In: J.H. Hartman,

K.R. Johnson and D.J. Nichols, eds., The Hell Creek Formation and the Cretaceous-Tertiary Boundary in the Northern Great Plains: An Integrated Continental Record of the End of the Cretaceous. Geological Society of America Special Paper 361, p. 169-176.

Traverse, A., 2007. Paleopalynology, Second Edition. Springer, Dordrecht, The Netherlands, 813 p. A Late Pliocene to Present Day Diatom Record from the Bering Sea Zuzia Stroynowski Institution: IPMA (Portuguese Institute for Marine and Atmospherics) , Dept of Marine Geology [email protected]; [email protected] Fossil diatoms are the principal component of Bering Sea sediments and reflect the paleoceanographic history of the region. Diatom accumulation rates and relative abundances at IODP site U1340A are presented. Overall, the 4.9 Ma total diatom productivity record reveal a steep reduction at ca. 4.2 Ma from ~45 x 107 – 6 x 107 wet valves/g, signifying a major shift in the upwelling and/or nutrient regime. Further abrupt shifts in the diatom assemblage occur at 1). 2.78-2.55, 2). 2.0-1.8 and 3). 1.0 - 0.88 Ma. 1). At 2.78-2.55 Ma, the appearance of sea-ice related species marks the expansion of Northern Hemisphere ice sheets, subsequent development of stratified, nutrient-depleted waters, and increased influence of western water masses (most likely due to the suppressed inflow of Alaskan Stream). High values of mat-forming species, Thalassiosira longissima suggest a more intense frontal system driven by increased wind strength developed at this time. 2). 2.0-1.8 Ma denotes a rapid cooling as sea ice duration and/or frequency increased. This, coupled with low sea level stands caused prolonged closure of the Aleutian Passes, coupled with increased Western Basin Water inflow. 3). The shift to 100 ka glacial/interglacial cycles at the Mid-Pleistocene Transition (1.0 - 0.88 Ma) marked an increase in surface water mixing (upwelling). However, the basin remained semi-isolated suggested by further diminished Alaskan Stream influence. Reduced summer stratification may have been caused by increased influence of waters from the eastern and northeastern shelf. These records provide evidence that the development and changing dynamics of sea ice in the Bering Sea played a major role in subarctic ocean circulation and is an integral component of global climate change.


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A Global Perspective on Local Biostratigraphy: An Example from the Scotian Shelf Amy Taylor and Zach Ollerton Neftex Petroleum Consultants Ltd., 97 Milton Park (2nd Floor), Abingdon, Oxfordshire, OX14 4RY, United Kingdom [email protected] A vast volume of public domain biostratigraphic data have been identified for the Scotian Shelf. However, the utility of these data, typically summarised in local biostratigraphic schemes or distribution charts, requires calibration against international standards to facilitate precision in wider stratigraphic correlations, critical in hydrocarbon exploration workflows. Despite general standards in nomenclature and referencing, no consistent format is applied in the presentation of published biostratigraphic data. This inconsistent approach potentially limits correlation on a wider scale. Biostratigraphic data are reviewed using current geochronology concepts as defined in the International Time Scale (Gradstein et. al., 2012), while adhering to the original author’s event-ordering. These data are calibrated and reviewed by consultant biostratigraphers in their areas of expertise. The data are presented in a consistent and concise format which can be interrogated and displayed using software endorsed by the International Commission of Stratigraphy, Time Scale Creator Pro. A synthesis scheme can be built based on all the biostratigraphy available for that basin, through identification of key events found within the publically available data. These synthesis zones and events are not restricted to a specific taxon group and focus on key time periods of petroleum interest within a basin. The integration of the biostratigraphy and lithostratigraphy correlated to a sequence stratigraphic model refines the understanding of the regional-scale geological evolution of the region and implications for hydrocarbon prospectivity. Here we will present an application of a synthesis scheme within the Scotian Shelf and demonstrate how this improves the geological understanding in the area. Modern Dinoflagellate Cyst Distribution in the Gulf of Papua M.L. Thomas ([email protected])1, S. Warny1, S.J. Bentley1, A.W. Droxler1, and D.M. Jarzen2 1Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA, U.S.A. 2Department of Earth Sciences, Rice University, Houston, TX, U.S.A. 3Paleobotany and Palynology, Cleveland Museum of Natural History, Cleveland, OH, U.S.A. The modern distribution of dinoflagellate cysts in the Gulf of Papua was evaluated to determine if cyst assemblages could serve as a proxy for current oceanographic conditions, including temperature, salinity, and nutrient concentrations. While researchers have performed palynological analysis of nearby sites in the Torres Strait and the Coral Sea as well as on Papua New Guinea, they focused predominantly on the vegetation component of the record with little attention to dinoflagellate cysts. 40 sediment samples of the top 0-4 cm from the PANASH (2004) and PECTEN (2005) cruises were obtained and processed from 40 core locations throughout the Gulf of Papua. The processing procedure involved digestion with 10% HCL to dissolve carbonates and 70% HF to dissolve silicates, followed by heavy liquid separation with ZnBr2 and oxidation with Schulz solution. Slides were produced for palynological analysis and counted according to widely accepted statistically significant values of at least 300 specimens per slide. Analysis was conducted at Louisiana State University’s CENEX (Center for Excellence in Palynology) laboratory with an Olympus BX43 light microscope. Principal component analysis (PCA) was performed to correlate modern dinocyst distribution with environmental parameters, including temperature, salinity, and nutrient conditions. Preliminary results provide insights into the distribution of dinoflagellate cysts in the Gulf of Papua. Assemblages varied among sample locations, primarily due to salinity differences, as well as distance from the shore. High abundances of reworked dinoflagellate cysts were found at sites near the coastline where fluvial transport brings in elevated siliciclastic sediment discharge, while few reworked dinocysts were present in locations far offshore, particularly in Ashmore Trough east of the Great Barrier Reef.


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Middle - Late Miocene Planktonic Foraminifera Biostratigraphy and Paleoecology in the Ladrilleros – Juanchaco Sequence; (Pacific Coast Of Colombia) Raúl A. Trejos Tamayo1,2, Francisco J. Sierro2, Andrés Pardo Trujillo1, Felipe Vallejo1,2, Angelo Plata1,2, José-Abel Flores2. 1 Institute on Stratigraphic Research – University of Caldas, 275 Manizales, Colombia 2 Department of Geology – University of Salamanca, 37008 Salamanca, Spain [email protected]; [email protected] Few micropaleontological studies have been carried out on Neogene onshore sequences from the northwestern corner of South America (Duque-Caro, 1990 a, b; De Porta, 2003; Coates et al., 2004). These studies have revealed different episodes of instability related to tectonic and climatic events that were mainly caused by the development and accretion of the Panama arc to the northwestern edge of South America. However, these studies lack detailed chronostratigraphy, especially during the early Neogene. In this sense, the continuous sedimentary sequence of Ladrilleros – Juanchaco located along the unknown, southern pacific coast of Colombia, becomes an excellent option to study the process of continental exhumation and constrain the timing of the geological events that triggered an overland route between South and Central America. The Ladrilleros – Juanchaco section is a terrigenous succession, composed mainly of mudstone at the bottom with increasing influence of sandstones bed towards the top. In this study we report the first data from quantitative planktic foraminifer assemblages from Colombia pacific margin, which are correlated with a series of bioevents from middle Miocene that were astronomically dated (by Lourens et al., 2004). As a result we have been able to create an age model that can be used to interpret the sedimentary succession as well as the paleoceanographic change observed in this coastal section. We identified five biostratigraphic zones from N8 to N13? (Lowest Occurrence P. glomerosa; LO O. universa; LO F. peripheroacuta; LO F. foshi and Highest Occurrence F. foshi ?); that allow a correlation of the Ladrilleros section with Langhian and Serravalian stages (Lourens et al., 2004). The sequence shows, abrupt changes on the sedimentary pattern at 12,9 My (N12), indicated by presence of high levels of slump structures and convolute lamination, suggesting tectonic disturbance in the sedimentary sequence. Further, a big regional hiatus (NH3) marked by changes in the sedimentation rate, increase in the coarse fraction, and reduction in the planktonic foraminifera per gram was identified. Change in the ratio of warm–oligotrophic vs. cold-eutrophic planktic foraminifera allowed us to elaborate a paleoclimate record for this section. This index shows a trend towards colder and more eutrophic conditions along the section. Nevertheless, an important change was observed between 14.3 My and 13.6 My and at 12.9 My, when cold species (Gg. bulloides, Gg. glutinata and Neogloboquadrinids) decreased in abundance while the warm – oligotrophic species (Gs. obliquus, Gs. sacculifer, O. universa and Gg, apertura) were dominant (Fig. 1); this event occurs just before the middle Miocene Antarctic ice sheet expansion. The data presented herein have an important implication since they are correlatable with one of the most remarkable rising pulses of Panama arc, restricting the passages of deepwater between the Caribbean Sea and the Pacific Ocean. Coates, A. G., Collins, L. S., Aubry, M-P., Berggren, W. A., 2004. The Geology of the Darien, Panama, and the late Miocene-

Pliocene collision of the Panama arc with northwestern South America. Geological Society ofamerica Bulletin, 116; (11/12), pp. 1327-1344.

De Porta, J., 2003. La formación del istmo de Panamá. Su incidencia en Colombia. Rev. Acad. Colomb. Cienc. 27(103): 191-216. Duque-Caro, H., 1990a. The Choco Block in the northwestern corner of South America: Structural, tectonostratigraphic, and

paleogeographic implications. Journal of South American Earth Science, Vol, 3, (1), pp. 71-84. Duque-Caro, H., 1990b. Neogene stratigraphy, paleoceanography and paleobiogeography in northwest South America and the

evolution of the Panama Seaway. Palaeogeography,Palaeoclimatology, Palaeoecology 77, pp: 203 – 234. Lourens, L., Hilgen, F., Shackleton, J., Laskar, J., Wilson, D., 2004. The Neogene Period in: Gradstein, F.M., Ogg, J.G., Smith, A.G.

(Eds.), Geological Time Scale 2004. Cambridge University Press, pp. 409–440.


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Fig.1. Time scale of planktonic foraminifer zones (by Lourens et al., 2004) correlatable with a Sedimentary sequence of Ladrilleros – Juanchaco; in blue: planktic foraminifera per gram of dry sediment and in green: distribution of the ratio of warm-oligotrophic vs. cold-eutrophic foraminifera.

Middle - Late Miocene Calcareous Nannofossils Biostratigraphy and Paleoceanography of the Ladrilleros – Juanchaco Sequence, Eastern Equatorial Pacific - Colombia Diego-Felipe Vallejo1, 2, José-Abel Flores2, Andrés Pardo1, Francisco J. Sierro2, Raúl Trejos1, 2, Angelo Plata1, 2

1Instituto de Investigaciones en Estratigrafía (IIES)-Universidad de Caldas, Colombia. 2Grupo de Geociencias Oceánicas (GGO)-Universidad de Salamanca, Spain. [email protected], [email protected] Western Colombia is a key region to understand origin, evolution and story of hydrocarbon system. Biostratigraphic investigation in this area has been limited due to dense tropical forests and lack of outcrops. Ladrilleros-Juanchaco is a continuous sedimentary sequence of ~700 meters thick, well preserved and almost no tectonic deformation. This section is located on the Pacific coast of Colombia, southward of the Panama-Choco Block. Several micropaleontological analyses were carried out in the Ladrilleros-Juanchaco sequence, including diatoms, foraminifera, calcareous nannofossils, radiolarian and palynomorphs. In this study we carried out the quantitative analysis of calcareous nannofossils in 200 samples systematically recovered. These analyses allow us to develop a biostratigraphic frame for the middle-late Miocene on the northwest corner of South America. A total of eight biostratigraphic events were recognized, six of them calibrated astronomically. The bioevents were compared to studies in ODP-Leg 138 material, identifying standard zonations of (Martini, 1971; Okada & Bukry, 1990). From the base to the top: last occurrence (LO) of Helicosphaera ampliaperta, first occurrence (FO) of Reticulofenestra pseudoumbilicus (>7µm), LO Sphenolithus heteromorphus, last common occurrence (LCO) of Cyclicargolithus floridanus, first common occurrence (FCO) of Discoaster kugleri, FO Discoaster bollii, LCO Discoaster kugleri and FO Catinaster coalitus (Figure 1). The biohorizons mentioned here suggest that the Ladrilleros-Juanchaco section was deposited during the Langhian and Tortonian (14.91 to 10.88 Myr), between NN4 (CN3) and NN6 (CN5a) zones of Martini (1971) and Okada & Bukry (1990), respectively.


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Paleoecology: At the base of the sequence, during the Langhian (15-14 Myr) the high abundances of Sphenolithus spp., Discoaster spp. and Umbilicosphaera spp., allow us to conclude that the surface water masses were warm and oligotrophic. Moreover, during the Serravallian and Tortonian (after to 12 Myr), a progressive increase towards the top of species such as Reticulofenestra pseudoumbilicus (>5µm) shows that the Equatorial Eastern Pacific was dominated by cold-eutrophic waters. Interestingly, the sedimentary record and micropaleontological analysis during the late Serravallian (12-13 Myr) reveal an abrupt decline of the sedimentation rate as well as major changes in the abundance and state in the nannofossil assemblages. These features have been reported in other sequences and traditionally linked to the Closure of the Isthmus of Panama and/or a general reorganization of Pacific circulation. Martini, E., 1971. Standard Tertiary and Quaternary calcareous nannoplankton zonation. Roma 1970, 2, 739 785. Okada, H., & Bukry, D., 1990. Supplementary modification and introduction of code numbers to the low-latitude coccolith

biostratigraphic zonations. Marine Micropaleontology 5, 321–325.

Figure 1. Abundance patterns of middle and late Miocene selected calcareous nannofossils in the Ladrilleros-Juanchaco sequence. New Structural Observations within Coccolithus, Clausicoccus, Toweius, Prinsius and Reticulofenestra Osman Varol [email protected] Varol Research, 5212 Sagesquare Street, Houston TX 77056 New structural features have been identified in Coccolithus, Clausicoccus, Toweius and Prinsius, and the interpretation of these observed features differ from previous interpretations. Identified features such as locking pores and beaded elements are essential in strengthening the connection between individual units that form specimens from the Coccolithus, Clausicoccus, Toweius and Prinsius. Variations in the construction of the inner and outer tube cycles, interlocking character of the tube cycle/proximal shield and design of the central mesh will be discussed and compared among Coccolithus/Clausicoccus, Toweius/Prinsius and Reticulofenestra. In Toweius and Prinsius, the inner and outer tube cycles are well-developed and exposed distally. The inner tube cycle is also exposed proximally, where it demonstrates bifurcation. The most proximal arm of the bifurcating inner tube cycle interlocks in “jigsaw fashion” with the locking pores on the proximal shield. The central mesh extends from an additional arm of the bifurcating inner tube cycle.


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In Coccolithus and Clausicoccus, only the outer tube cycle is well developed and exposed distally. The inner tube cycle is vestigial, usually fused to the outer tube cycle. Therefore, the inner tube cycle is only exposed proximally, where it also demonstrates bifurcation. As in Toweius and Prinsius, there is a “jigsaw-like” interlocking on the proximal shield between the proximal arm of the inner tube cycle and the locking pores, and similar construction of the central mesh within Coccolithus and Clausicoccus.


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Two central tube cycles exist in Reticulofenestra. The outer tube cycle is only exposed distally, whilst elements of the inner tube cycle are not exposed in a complete specimen. The proximal ends of the inner tube cycle are partially inserted between the elements of the proximal shield, but are not exposed proximally. The inner tube cycle elements are very thin, and are usually fused to the outer tube cycle elements. The outer tube cycle is inserted between the distal shield and the inner tube cycle in a “door peg fashion,” to lock the different units of the specimen together (e.g. proximal shield-inner wall-distal shield). The central mesh extends partly from the inner tube cycle elements, and partly from proximal shield elements.

Taxonomic Revision of Helicosphaera and its Contribution to Cenozoic Biostratigraphy Osman Varol [email protected] Varol Research, 5212 Sagesquare Street, Houston TX77056 Helicosphaera are one of the most important components of the Cenozoic nannofossil assemblages. Their common occurrence, short ranges, distinct inception and extinction points together with easy identification make them ideal zonal or subzonal markers. Helicosphaera is made up of three structural units: the flange, the blanket and the proximal plate. The blanket extends through the central opening of flange. It may be confined to the central opening or partly or entirely cover the distal surface of the flange. In this study variations of blankets are considered to be the primary subdivision of Helicosphaera. Four types of blankets were observed in Helicosphaera. The ampliaperta type and walbersdorfensis type blanket corresponds to blanket type I of Theodoridis (1984) whilst recta type blanket correspond to blanket type II of Theodoridis (1984). The carteri type blankets correspond to the blanket type III of Theodoridis (1984).


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The wing terminations are considered to be the second important criteria for identification of Helicosphaera. There are three main wing terminations observed in Helicosphaera. These are extending, non-extending and truncated*. The extending wing usually terminates above the short axes of the species [Helicosphaera carteri ] whilst non-extending wing always terminates beyond the short axis of the species [Helicosphaera walbersdorfensis ]. The truncated wing terminations have two variations; the wing terminations that do not reach to meta-pterygal side as in Helicosphaera recta and the wing terminations that do reach to meta-pterygal side, as in Helicosphaera bramlettei, Helicosphaera wilcoxonii and Helicosphaera philippinensis. In Helicosphaera, the central area can be closed as in Helicosphaera burkei or open as in Helicosphaera ampliaperta. Open central areas may be spanned by conjunct bar as in Helicosphaera walbersdorfensis or disjunct bar as in Helicosphaera intermedia.

The orientation of the bars is another important feature for the identification of the Helicosphaera species. The bars can be transverse as in Helicosphaera crouchii [conjunct] or in Helicosphaera sp. 3 [disjunct]. The axial disjunct bar is present in Helicosphaera euphratis whilst an oblique conjunct bar is recognized in Helicosphaera wallichii. An inverse conjunct bar is present in Helicosphaera perch-nielseniae and Helicosphaera obliqua. No axial conjunct bars and inverse disjunct bars have been reported so far.


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The identification key and the ranges for the Helicosphaera species will be discussed in detail. Theodoridis, S., 1984. Calcareous nannofossil biozonation of the Miocene and revision of the helicoliths and discoasters. Utrecht

Micropaleontol. Bull. 32, 3–271. Paleoceanographic and Paleoglacial Reconstruction of Barilari Bay, Western Antarctic Peninsula from the Benthic Foraminiferal Record Ryan Verbanaz, Scott E. Ishman

Department of Geology, Southern Illinois University-Carbondale, Carbondale, IL 62901, USA ([email protected]) The Antarctic Peninsula (AP) is one of three regions that have experienced Recent Rapid Regional (RRR) warming in that last 50 years (Vaughn et. al., 2003). Temperature increases of the AP during the 20th century are five times greater than the global mean (Bentley et. al., 2009). The increasing rate of temperatures has led to changes in species distributions, disintegration of ice shelves, accelerated retreat of continental glaciers, and possibly increased rates of global sea-level rise (Bentley et. al., 2009). To determine if the recent ice shelf retreat is unique or has previously occurred within the Holocene, further investigations of the environmental variability of Antarctic Peninsula need to be conducted (Domack et. al., 2003). This study used Jumbo Piston Core 126, collected from the Nathaniel B. Palmer during cruise NBP10-01, to investigate environmental variability in Barilari Bay, western Antarctic Peninsula as part of the LARsen Ice Shelf System, Antarctica (LARISSA) project. A total of 107 samples of 2cm thickness were collected every 20cm from a 21.42m core and washed through a 63µm sieve leaving foraminifera equal or greater than 63µm. Each benthic foraminiferal test was identified to the species level using taxonomic concepts of Loeblich and Tappan (1988), Igarashi et. al. (2001), and Majewski (2005). Benthic foraminiferal biofacies are useful indicators of changes in the benthic environment caused by ice shelf collapse (Ishman and Szymcek, 2003) since water mass characteristics influence foraminiferal distributions of the Antarctic (Anderson, 1975; Ishman and Domack, 1994; Szymcek et. al., 2007). Benthic foraminiferal data from Jumbo


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Piston Core 126 was analyzed using Principal Component (PC) and cluster analyses to assist in the Holocene oceanographic and climatic interpretation of Barilari Bay. The first three principal components explain 79.5% of the variance in the foraminiferal abundance data. PC1 comprises 49.6% of the variance and represents the Bulimina aculeata assemblage. PC2 and PC3 explain 16.3% and 13.6% of the variance and characterize the Fursenkoina fusiformis and Pseudobolivina antarctica assemblages (Figure 1), respectively. Most arenaceous tests decrease downcore, possibly attributed to post-depositional diagenetic alteration. The calcareous taxa in this study are indicative of non-corrosive bottom waters. F. fusiformis assemblage includes the calcareous benthic Astrononion echolsi and represents the presence of Ice Shelf Water (ISW). The P. antarctica assemblage includes agglutinated forms Adercotryma glomeratum and Portatrochammina antarctica and is indicative of Hyper Saline Shelf Water (HSSW). The B. aculeata assemblage is associated with Circumpolar Deep Water (CDW) (Ishman and Domack, 1994) Sediments from ~1100-950 calibrated years Before Present (cal. yr BP) are characterized by the B. aculeata assemblage, indicating the presence of CDW. At ~950 cal. yr BP the CDW receded coincident with glacial conditions observed during the Little Ice Age. The ~950-350 cal. yr BP interval represents glacial conditions interpreted from the high abundance of the P. antarctica assemblage and a drop in foraminifera abundances due to HSSW and a high sedimentation rate from glacial runoff. Intermittent pulses of CDW are observed between the 950-350 cal. yr BP interval, expressed by the peaks in the B. aculeata assemblage. Between ~300 and 100 cal. yr BP the middle of the fjord was dominated by ISW denoted by the high abundance of the F. fusiformis assemblage. At ~375 cal. yr BP CDW began to move back into Barilari Bay causing glacial retreat and initiated ISW production.

Figure 1. Eigen Values for principal components 1-3. The last column on the right depicts benthic foraminifera abundance for each sample. The yellow interval represents non-retrieved samples. The spacing of drop lines indicates sedimentation rate.

Bentley M.J., Hodgson D.A., Smith J.A., Cofaigh C.O., Domack E.W., Larter R.D., Roberts S.J., Brachfeld S., Leventer A., Hjort C.,

Hillenbrand C-D., Evans J., (2009), Mechanisms of Holocene palaeoenvironmental change in the Antarctic Peninsula region, The Holocene, 19, 51-69.

Domack E., Burnett A., and Leventer A. (2003), Environmental setting of the Antarctic Peninsula, Antarctic Research Series, 79, 1-13.

Igarashi A., Numanami H., Tsuchiya Y., and Fukuchi M., (2001), Bathymetric distribution of fossil foraminifera within marine sediment cores from the eastern part of Lutzow-Holm Bay, East Antarctica, and its paleoceanographic implications, Marine Micropaleontology, 42, 125-162.

Ishman S., and Domack E., (1994), Oceanographic controls on benthic foraminifers from the Bellingshausen margin of the Antarctic Peninsula, Marine Micropaleontology, 24, 119-155.


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Ishman S., and Szymcek P., (2003), Foraminiferal distributions in the former Larsen-A Ice Shelf and Prince Gustav Channel region, eastern Antarctic Peninsula margin; a baseline for Holocene paleoenvironmental change, Antarctic Research Series, 79, 239-260.

Loeblich Jr., A.R., and Tappan H., (1988), Foraminiferal Genera and their classification. Van Nostrand Reinhold, New York, 1-970. Majewski W., (2005), Benthic foraminiferal communities: distribution and ecology in Admiralty Bay, King George Island, West

Antarctica, Polish Polar Research, 26, 159-214. Szymcek P., Ishman S., Domack E., and Leventer A. (2007), Holocene oceanographic and climatic variability of the Vega Drift

deduced through foraminiferal interpretation, 10th International Symposium on Antarctic Sciences. Vaughan D.G., Marshall G.J., Connolley W.M., Parkinson C., Mulvaney R., Hodgson D.A., King J.C., Pudsey C.J., Turner J., (2003),

Recent rapid regional warming on the Antarctic Peninsula, Climate Change, 60, 243-274. Biofacies Characterization: The First Step Towards Property Prediction in Shale Gas Exploration - An Example from the Posidonia Shale in the Netherlands Verreussel, R.M.C.H1., Van Bergen, F. 1, Horikx, M1., Munsterman, D.K1., Nelskamp, S1. and Zijp, M.H.A.A. 1, Houben, A.J.P.1 1 TNO/Geological Survey of the Netherlands, Petroleum Geosciences, Utrecht, The Netherlands [email protected] A key factor in shale gas exploration is being able to predict the reservoir properties. Unfortunately, most organic-rich shales are heterogeneous in a vertical and horizontal sense. The first step towards property prediction is biofacies characterization. A palynological and geochemical study is carried out on three wells on an onshore-offshore transect. Based on the results, it is concluded that anoxia last 1.5 million years longer in the proximal location. It appears that the main driver for stratification of the water column is fresh water influx. The most intense water column stratification, associated with the highest organic carbon concentrations, occurs around the so-called Early Toarcian Carbon Isotope Event. The palynological results indicate an abrupt change in climate from warm and arid to humid and a gradual return to arid conditions. Two types of algae dominate the Posidonia: Tasmanites, with a high Hydrogen Index (HI), and “sphericals” with a low HI. Tasmanites mark the transition from normal marine to stratified marine conditions and are more abundant in the distal setting. The “sphericals” dominate the most intensely stratified marine intervals. The “sphericals” are probably better adapted to prolonged low salinity conditions. The next step is to link biofacies to physical properties and construct a predictive property model. Non-Pollen Palynomorphs as Proxies of Cultural Eutrophication of Lake Simcoe, Ontario Olena Volik1, Donya С.Danesh 2, Francine M.G.McCarthy3, Matea Drljepan4

1 Department of Earth Sciences, Brock University, St. Catharines ON, Canada L2S ЗА1, [email protected]; 2 Department of Biology, Queens University, Кingston, ON, Canada K7L ЗN6, [email protected] ; 3Department of Earth Sciences, Brock University, St. Catharines ON, Canada L2S ЗА1, [email protected]; 4 Department of Earth Sciences, Brock University, St. Catharines ON, Canada L2S ЗА1, [email protected] Lake Simcoe, the largest lake in Southern Ontario (area 722 km2), is situated 40 km southeast of Georgian Bay and 70 km north of the Lake Ontario. The watershed has a total land area of a~2,857 km2 and incudes 18 subwatersheds. The lake consists of the main basin and two bays: the narrow and deep (>35 m) Kempenfelt Bay, and the relatively shallow (<15 m) Cook’s Bay (LSSAC, 2008). Since European settlement beginning in the early 1800s, the Lake Simcoe watershed has supported agriculture and industry, provided drinking water for 23 municipalities, and has been used to assimilate waste water. These human activities associated with increased nutrients input have disturbed the ecosystem causing a shift in trophic status of the lake. Due to natural features and differences in the extent of anthropogenic impact within the subwatersheds, the level of eutrophication varies within the lake. In general, total phosphorous (TP) levels are the highest in Cook’s Bay (~22.7 µg/L), followed by Kempenfelt Bay and the main basin (each ~13.3 µg/L), and are lowest in the outflow at the Atherley Narrows (~10.2 µg/L) (Eimers et al., 2005). While simple measurement of TP concentration in water presents only a brief synoptic snapshot, the analysis of non-pollen palynomorphs reflects long-term human impact. In order to assess the response of NPP to anthropogenic change, we analyzed cores from three parts of Lake Simcoe with different levels of eutrophication: Cook’s Bay, the main basin, and Smith’s Bay near the Atherley Narrows. The distribution of NPP in cores from Cook’s Bay and the main basin shows similar trends. Low concentrations of nutrients in samples with little nonarboreal pollen (NAP) in sediments deposited during pollen zones 1 through 3 of McAndrews (1994) record low disturbance prior to early European settlement. Oligotrophic species (Cosmarium spp., Euastrum spp., Staurastrum spp. and Pediastrum integrum) prevail in deposits from the pre-European colonization period, as the Native (Iroquois) population had relatively insignificant impact on the environment. However, the upper


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part of zone 3d is characterized by an increase in thecamoebians (Difflugia obolonga, in particular) and sporadic appearance of dinoflagellates (Peridinium wisconsisnensis) that record incremental growth in nutrients’ influx into the lake because of stronger presence of Native inhabitants. Subsequent European settlement and significant changes in land use are reflected in variations in NPP assemblages. Increased euthrophication is confirmed by a shift from oligotrophic algal assemblages to eutrophic assemblages (Staurastrum chaetoceras, S. pingue, Cosmarium botrytis, C. formosulum, Pediastrum boryanum var. boryanum, P. boryanum var. pseudoglabrum), together with an increase in dinocysts (Parvodinium inconspicuum, Peridinium wisconsinensis, P, willei, P. volzii), thecamoebians (especially Difflugia spp., Centropyxis spp, and Cucurbitella tricuspis), and ciliates (Codonella cratera) up-core. The most prominent changes appear to record peaks of anthropogenic impact, such as Holland Marsh draining and post-WWII urbanization and industrialization. The draining of the Holland Marshes in the 1920’s and 1930’s is recorded by maximum concentration of dinocysts (Parvodinium inconspicuum, Peridinium wisconsinensis, P, willei, P. volzii), Centropyxis aculeatа and С.constricta. Onset of bottom water hypoxia is indicated by the appearance of Codonella cratera and Cucurbitella tricuspis, taxa which can survive because of their planktonic life habits. In addition, a sharp increase in nutrient levels in sediments together with transition from high nitrite to high nitrate concentrations record a sudden increase in BOD leading to depletion of DO associated with the creation of polders. Post-WWII urbanization and industrialization is confirmed by maximum concentration of Cucurbitella tricuspis and Codonella cratera, peaks of Pediastrum spp. and Peridinium spp., abundance of Codonella cratera, and dominance of Сentropixis aculeata and Cucurbitella tricuspis. In the core from Smith’s Bay, the distribution of NPP shows rather gradual changes in trophic status, without dramatic peaks of NPP concentration found in other cores. Sediments deposited prior to European settlement are rich in oligotrophic species (Staurastrum punctulatum, E. insulare, E. binale, Pediastum integrum). Mesotrophic species increase in abundance up-core (Euastrum bidentatum, Cosmarium depressum, C. subcostatum, C. rectangulare, C. angulosum, C. reniforme, Pediastrum simplex). The upper part of the core is characterized by a significant number of eutrophic species (Staurastrum chaetoceras, S. pingue, C.botrytis, C. formosulum, C. protractum, Pediastrum, boryanum var. boryanum, Pediastrum, boryanum var.pseudoglabrum). Cucurbitella tricuspis and Codonella cratera are virtually absent in the samples, indicating a lack of bottom water anoxia at this site. In addition, only sporadic dinocysts were found, but it’s not clear whether this resulted from low nutrient concentration or from taphonomy, as the sediments are very calcareous and alkalinity does not favour cyst preservation. In conclusion, the distribution of NPP in the cores match spatial differences in TP concentrations within the lake, showing that the level of eutrophication decreases gradually from Cook’s Bay to the Attherley Narrows outflow due to differences in the extent of anthropogenic impact as well as to cumulative retention of phosphorous within sediments. Moreover, changes in assemblages and concentration of NPP from the bottom to the top of the cores correspond with the history of settlement within Lake Simcoe basin, recording temporal differences in eutrophication.

Figure 1. Non-pollen palynomorphs from Lake Simcoe: a) Pediastrum boryanum var. boryanum, b) P. integrum, c) P. cornutum, d) P. boryanum var. pseudoglabrum, e) Peridinium volzii, f) P. willei, g) P. wisconsinensis, h) Parvodinium inconspicuum, i) Staurastrum chaetoceras, j) S. pingue, k) Euastrum bidentatum, l) Cosmarium protractum, m) C. botrytis, n) Codonella cratera, o) Centropixis aculeata discoides, p) C. aculeata aculeata, q) C. constricta Danesh, D., McCarthy, F.M.G., Volik, O., Drljepan, M. (accepted). Non pollen palynomorph record of cultural eutrophication in Lake

Simcoe. Palynology.


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Eimers, M. C.; Winter, J. G.; Scheider, W. A.; Watmough, S. A.; Nicholls, K. H. (2005) Recent changes and patterns in the water chemistry of Lake Simcoe. Journal of Great Lakes Research 31(3): 322-332

Lake Simcoe Science Advisory Committee (LSSAC). 2008. Lake Simcoe and its watershed: a report to the Minister of the Environment. The Queen’s Printer, ON, Canada

The Time Has Come: Advances in Cenozoic Tropical Planktonic Foraminiferal Biochronology Bridget S. Wade School of Earth & Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK. [email protected] Department of Earth Sciences, University College London, Gower Street, London, WC1E 3BT, UK. Planktonic foraminifera are extensively utilized in Cenozoic marine biostratigraphy. Dating of biostratigraphic events has been based largely on correlations to the magnetostratigraphy in deep sea cores of the Deep Sea Drilling Project and Ocean Drilling Program, as well as outcrop sections. However many bioevents were calibrated in the 1980s using incomplete rotary cores, while other events have only been calibrated at relatively low resolution. Advances in drilling technology coupled with the development of the astronomical time scale (ATS) for the Neogene and part of the Paleogene now provides the opportunity to re-evaluate Cenozoic bioevents at much higher resolution than previously attempted. Wade et al. (2011) synthesized an amended low-latitude (tropical and subtropical) Cenozoic planktonic foraminiferal zonation with calibrations to the ATS of the Neogene and late Paleogene and geomagnetic polarity time scale (GPTS) of the Cenozoic. This synthesis led to major adjustments to the duration of some biochrons. I present the recent developments, progress, problems and frustrations of Cenozoic planktonic foraminiferal biochronology. Wade, B.S., Pearson, P.N., Berggren, W.A. and Pälike, H., 2011. Review and revision of Cenozoic tropical planktonic foraminiferal

biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth Science Reviews, 104: 111-142. Potential Industrial Applications for Nannofossil Paleoecological Indices on Input to Deepwater Reservoir Characterization: Examples from Miocene Gulf of Mexico Ryan D Weber and Lawrence Febo, BP America, Inc, [email protected] As improved data collection techniques evolve, nannofossil data has not only been ideal for chronostratigraphic and correlative applications, but has shown utility in characterizing deepwater reservoirs when used in conjunction with benthic foraminiferal and palynological data. A detailed comparison between calcareous nannofossil abundances from various penetrations in highly expanded Middle Miocene deepwater Northern Gulf of Mexico hydrocarbon fields suggests that variations in fossilized phytoplankton communities thought to have been caused by cyclical surface water dynamics can be utilized to compliment standard zonations and facies analyses from other fossil and sedimentological data. Genera contributing to these assemblage variations are Coccolithus, Discoaster, Helicosphaera, size and rim-varied Reticulofenestra, Sphenolithus, and Umbilicosphaera. Surface water dynamics are assumed from nannofossil assemblages (summated by Flores et. al., 2005) and are otherwise unmeasured, but could ultimately be controlled by an unidentified depositional facies regime. Nonetheless, the application for paleoecological analyses is to help characterize heterogeneity within reservoirs, and ultimately assist with flow-unit interpretation. Additionally, similar trends in the overburden observed from numerous penetrations suggest cyclical regional controls over geological time, which can be used for local and/or regional correlation to support global standard zonations. Flores, Jose-Abel, et. al., 2005, Surface water dynamics and phytoplankton communities during deposition of cyclic late Messinian

sapropel sequences in the western Mediterranean, MARINE MICROPALEONTOLOGY, v.56, p.50-79.


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Oxygen Isotope Variability in Ordovician & Silurian Conodonts: Validating the Ion-Microprobe Analysis of Individual Conodont Elements J.R. Wheeley1, M.P. Smith2 & I. Boomer1

1School of Geography, Earth & Environmental Sciences ([email protected]), University of Birmingham, Birmingham B15 2TT; 2Oxford University Museum of Natural History, Parks Road, Oxford, OX1 3PW.

Conodonts are potentially robust archives of climate. Previous ion microprobe conodont δ18O studies (e.g. Trotter et al., 2008) have proceeded directly to palaeotemperature interpretation without consideration of variability. We show that ion-microprobe analyses of Ordovician and Silurian conodonts establishes that:

• intra-element crown tissue δ18O typically varies by ≤1‰, is normally ≤2‰ and rarely varies by 2-4‰; • δ18O can vary across elements, suggesting a microstructural and/or diagenetic control; • δ18O can vary between species representatives within a sample by <3‰; • δ18O of pelagic and nekton-benthic taxa can differ by <2.3‰; • Preparation/processing methods and thermal alteration influences δ18O.

Utilization of material with no consideration of geological context or processing history may introduce significant artefacts. A protocol for future conodont oxygen isotope ion microprobe studies (Wheeley et al., 2012) is proposed.

(1) Single elements should be analysed with a minimum of 10 closely spaced points. (2) Within a given sample, multiple elements of any given species should be analysed to ensure a

representative mean δ18O value, and to establish a pattern of population variability. (3) Analyses should avoid conodont elements with Colour Alteration Index (CAI) values of >1 (if at all possible),

corresponding to a maximum burial temperature of 80 °C. (4) There may be potential for the investigation of inter-specific differences owing to the mode of life. (5) The use of conodont elements processed using formic acid should be avoided. (6) The higher surface area to volume in small coniform elements may render them more susceptible to

alteration when organic acids are used in conjunction with heavy liquids. Additional investigation is needed, but if this proves to be the case it would be inadvisable to use small coniform elements in future ion microprobe studies.

(7) Ion microprobe analysis points should be located away from the element margins to eliminate any edge effects.

(8) When using existing collections, only conodont elements from samples with known processing histories should be analysed.

Conodont tissue types in Oulodus (Branson & Mehl) from the Ordovician Harding Sandstone (specimen BU2275).


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Wheeley, J., Smith, M.P. & Boomer, I. 2012. Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic

palaeoclimates and palaeoceanography. Journal of the Geological Society of London. 169: 239-250. Trotter, J., Williams, I.S., Barnes, C.R., Lécuyer, C. & Nicoll, R.S. 2008. Did cooling oceans trigger Ordovician biodiversification?

Evidence from conodont thermometry. Science, 321, 550–554. High Resolution Biostratigraphy and Integrated Seismic Sequence Stratigraphic Analysis of the Oxy Alban X1, Adriatic Sea, Offshore Albania Walter W. Wornardt Ph.D. MICRO-STRAT INC. [email protected] Samples from 250 to 2250 meters T.D. from the OXY Alban-X1 well in Block 3, Adriatic Sea, offshore Albania were analyzed and checklisted for calcareous nannofossils, planktonic and benthic foraminifers. The stratigraphic interval extends from Tortonian Stage, upper Miocene to the Piacenzian Stage, upper Pliocene. Nine (9) Vail Sequences with marker species were recognized from the 10.2 to 2.6 Ma sequences and are recorded on a Stratigraphic chart, a Seismic Sequence Stratigraphic Summary chart, and on Seismic Lines OXAB 91-19/19A and OXAB 91-32/32 EXT. The paleobathymetry varies from upper bathyal in the lower part of the well to outer to middle neritic in the Tortonian stage. Above these sediments a shallowing occurs in the Messinian and lower Zanclean stages followed by a deepening in the upper Zanclean and Piacenzian Stages. Important well developed lowstand shingled turbidite sands are recognized in Turonian 8.8 Ma and 8.2 Ma and in the Messinian 6.3 Ma Third Order Depositional Sequences (Vail Sequences). These potential reservoir sands seem to have a lateral component that are to be parallel to strike. The Third Order Depositional Sequences recognized in this well can be used as a framework to correlate depositional sequences, establish facies relationships, target reservoir sands and source rocks, and interpret seismic ties for the north-east Mediterranean area.

All CAI 1 from a Silurian sample from Onibury, UK, where the same sample was processed using different methods.

Darriwilian Greenland sample (all CAI 4; acetic acid digestion, bromoform separation).


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Genetic Sequence Stratigraphic Analysis: Using Calcareous Nannofossil and Planktonic Foraminifers in the Eagle Ford-Austin, and Bossier-Haynesville Formations Walter W. Wornardt Ph.D. MICRO-STRAT INC. [email protected] When drilling in the Bossier-Haynesville and Eagle Ford-Austin it is important to accurately, consistently identify and correlate the same zone of richness and brittleness in two or more wells. In addition to logs and seismic using calcareous nannofossils and planktonic foraminiferal and age datable maximum flooding surfaces identified in each well, provides a third data set for identification of these zones that are in-between the same age datable time lines, the maximum flooding surfaces (MFS). This methodology reduces risk in these expensive shale wells by verifying that the lateral that is going to be drilled or has been drilled is in the correct richness or brittleness zone. Bossier-Haynesville and Eagle Ford-Austin formations have be divided into a series of chronostratigraphic genetic Sequences between Stage/Age and numerical age datable Maximum Flooding Surface from the base of the Haynesville (top of Smackover) Ox7 SB to the approximate top of the Bossier, Ti5 MFS and from the base of the Eagle Ford (top of Buda) the Cenomanian (Ce3) sequence boundary to the top of the Austin, the Santonian (Sa3) Maximum Flooding Surface. The depositional expression of the MFS, the condensed section, is associated with fossil abundance peaks, Transgressive systems tract, high TOC, increased organic richness and have been correlated to the sequence stratigraphic cycle chart modified after Gradstein, 2012. High Resolution Biostratigraphy and Seismic Sequence Stratigraphic Analysis of the Amoco 24-1, North Darag Block, Gulf Of Suez, Egypt Walter W. Wornardt Ph.D. MICRO-STRAT INC. [email protected] High Resolution Biostratigraphy using calcareous nannofossils, foraminifers and palynomorphs was completed on 7 project wells using 1552 samples. Occurrence and abundance of each species were recorded on a checklist. Abundance intervals were identified to help identify the Maximum Flooding Surface and their MF Condensed sections. Well-log Sequence Stratigraphy was completed on 7 wells and Seismic Sequence Stratigraphy was interpreted on 11 (2-D) seismic lines in the North Darag Block, Gulf of Suez. The sediments range in age from Early Carboniferous to late Miocene. Eight 3rd order Sequences in the Miocene from the 23.8 Ma Sequence Boundary at the base of Nukhul Formation were it rests unconformable on the Cretaceous or Jurassic Five Jurassic Bathonian Sequences with shows in their reservoir sands were age dated and correlated in the seven wells in the North Darag Block. In North Darag block the “upper” and “lower” Nubia Sandstone was subdivided into five (5) second order Sequences instead of “Nubia A, B and C. Figure 1 is a correlation of 17-1A and GS 24-1 wells lower to middle Miocene, Nukhul,

Paleozoic five 2nd

order sequences

and Jurassic six 3rd

order sequences in North Darag Block

17-1A Well GS 24-1 Well


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Rudis, Kareem and Belayim Formation Paleozoic and Jurassic This is an example of Seismic Sequence Stratigraphic and High Resolution Biostratigraphic analysis was performed. A detailed analysis of the Amoco 24-1 well shown in Figure 1 is representative of the seven (7) wells used in this project (Fig. 2). This well was analyzed from 128.0 to 2865.0 meters, the Highstand of the Middle Jurassic, Bathonian 2 Third Order Depositional Sequence, to the middle Miocene 13.60 Ma Sequence Boundary. The Middle Jurassic ranges from 2865.0 meters to the top of the Callovian 3, at 2218.8 meters. The Bathonian 3, Bathonian 4 and Bathonian 5 sequences have very well developed sand packages with oil shows within the Transgressive Systems Tract. The Middle Jurassic sediments were deposited in a terrestrial/lacustrine fluvial to inner shelf environment. The Early Cretaceous, Aptian Stage, is represented by the Aptian 3 and Aptian 6 Third Sequences. The Late Cretaceous is represented by the Cenomanian 2, Cenomanian 3, Turonian 1 and Turonian 3 Sequences and terminate at the early Miocene, the 23.80 Ma Sequence Boundary. The Cretaceous sediments were deposited in an marginal marine to inner shelf environment. The base of the early Miocene, Nukhul Formation is recognized from the 23.80 Ma Sequence Boundary to its lithologic top at 1427.6 meters. It is interpreted as deposited in a marginal marine to outer shelf environment. Early Miocene sediments, from the 21.30 Ma Maximum Flooding Surface, to the 16.40 Ma Sequence Boundary are characterized by Lowstand prograding complex and relatively thin Transgressive and Highstand Systems Tracts in the Rudeis Formation. The middle Miocene sequences from 835.1 meters to 243.8 meters are represented by the 16.40 Ma and 15.60 Ma sequences and are approximately equivalent to the Kareem Formation.

The sediments deposited in the 16.40 Ma and 15.60 Ma Sequences are characterized by a thick Lowstand Systems Tract in the Kareem and Belayim Formations and are assigned to the Langhian to Serravalian Stages.


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Female Reproductive Morphotypes of Cytheridella Ilosvayi Daday, 1905 (Ostracoda, Crustacea) Detected by Morphological Analyses Claudia Wrozyna1, Werner E. Piller1, and Martin Gross2

1 University of Graz, Institute of Earth Sciences, Heinrichstrasse 26, A-8010 Graz, Austria, [email protected] 2 Universalmuseum Joanneum, Department for Geology & Palaeontology, Weinzöttlstrasse 16, A-8045 Graz Ostracods are well-known for their variety of reproductive modes. Nonetheless, there is only limited knowledge about morphological variability of soft and hard parts in relation to the reproduction mode. In particular, intraspecific morphological variation of coexisting parthenogenetic and sexual females lacks a sound documentation. We have investigated the intraspecific limb and shell variability of the neotropical freshwater ostracod species Cytheridella ilosvayi which has been known so far to reproduce only sexually. Limb variability of adult and juvenile individuals (down to A-3) is generally low. Though, highest variation is shown by podomere proportions of the antennas, while thoracopods and setae provide minor influence on the variability. Based on discrimination analyses shell parameters (i.e., shell length, position of the transversal sulcus) emerge to be more important for differentiation of groups than limb ratios. Adult females exhibit a large size range in which two clearly separated morphotypes exist. The presence of two morphologically similar females and only one type of males indicates a mixed reproduction population in which parthenogenetic and sexual reproduction coexists. According to correspondence in limb ratios between smaller females and males these are interpreted as being sexual. Consequently, the large females are assumed to be parthenogenetic.

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