the october 2004 mw=7.1 nicaragua earthquake: rupture process, aftershock locations, and the...

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1992 event slip distribution [Ihmlé, 1996]

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Broadband Seismographs:Tucan SEIZE Permanent

VolcanosSlab isobaths, 50 km interval

In This Issue:Science Articles

Nicaragua Earthquake ......... 1-2

Subduction Factory .............. 3-5

S2S Meetings Update ........... 6-7

From the Chair .........................8-9

CSDMS Infrastructure ..............10

EPO Spotlight........................11-12

MARGINS at AGU .....................14

AGU Sessions ................... 14-16

MARGINS Lecture/Reception 17

Contact Information .................23

Published bi-annually by the

MARGINS OfficeWashington University in St. Louis

1 Brookings Drive, CB 1169

St. Louis, MO 63130 USA

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No. 15, F

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2005

The October 2004 Mw=7.1 Nicaragua

earthquake: Rupture process, aftershock

locations, and the confluence of

SEIZE and SubFac goalsSusan Bilek (New Mexico Tech); Geoffrey Abers (Boston University);

Gustavo Reyes (Boston University); Karen M. Fischer (Brown University);Wilfried Strauch (Instituto Nicaragüense de Estudios Territoriales-INETER);

Victor Gonzalez Salas (OVSICORI)

The subduction zone off the Nicaraguacoastline has been the site of several largeearthquakes in the past decades, includ-ing the 1992 tsunami earthquake that wasanomalous in the size of the tsunami rela-tive to moment release [Kanamori andKikuchi, 1993]. As a focus site for boththe MARGINS-SEIZE and SubFac ini-tiatives, it is an area of keen interest forscientists interested in earthquake ruptureand volcanic processes.

The TUCAN group (Boston Univer-

sity, Brown University, INETER, andOVSICORI) has been funded throughMARGINS to investigate the uppermantle and subducting plate in Nicara-gua and Costa Rica, using an 18 monthdeployment of 48 broadband seismom-eters to sample the arc structure [Aberset al., 2004]. This experiment coinciden-tally recorded a large (M

w=7.1) earth-

quake that occurred along the plateinterface in a region close to the 1992 tsu-nami earthquake, and was the largest that

Figure 1. Map of recent seismic activity and experiments in the Nicaragua region. The 2004M

w 7.1 earthquake (star showing epicenter) occurred in a region close to the TUCAN

seismometers. The rupture area of the mainshock is shown by the black ellipse and aftershocksrecorded by the TUCAN network are shown by white circles. Slip from the mainshock occursdowndip of the slip from the 1992 tsunami earthquake (blue contours), and aftershocks covermuch of the shallow dipping seismogenic zone.

MARGINS Newsletter No. 15, Fall 2005 Science Article

that year (Figure 1). Because of the for-tuitous placement of so many broadbandseismographs, this event may be one ofthe best-recorded events anywhere on aninterplate thrust fault of a subductionzone. The New Mexico Tech group(Bilek) has collaborated with TUCANPI’s on a small project to combine analy-sis of the rupture process of the October2004 earthquake with the aftershocks re-corded by the TUCAN experiment.

Within 48 hours of the event, INETER(the Nicaraguan monitoring agency andTUCAN collaborators) were able to postinitial locations for over 100 aftershockson their web page. With the TUCAN data,retrieved in the following month, we wereable to relocate 120 aftershocks occur-ring in the first 5 days after the earth-quake. Gustavo Reyes did much of thisanalysis as an undergraduate intern atBoston University. Locations are gener-ally comparable to those determined byINETER with slightly less scatter indepth, as expected given the much densernetwork (Figure 2). Strong secondaryarrivals arriving 3-10 s after the P wavewere commonly observed in Costa Rica,at distances > 200 km. These signals mayreflect multipathing in the dipping sub-ducting slab, and suggest that the data setis rich in information about subductingplate structure. Continued work is test-ing the potential effects of three-dimen-

sional structure related to the slab on theaftershock locations, a potentially signifi-cant issue given that the events lie justoutside the array.

A preliminary point-sourcedeconvolution of 11 P and 4 SH wavesresolves an optimal depth for the earth-quake of 26 ± 4 km and a very simplemoment-release history with most mo-ment released within the first 16 s of rup-ture. A more detailed body-waveinversion technique provides informationon the full spatial extent of rupture[Kikuchi and Kanamori, 1991]. Inputsneeded for the inversion include focalmechanism, rise time and duration oftime functions, number of subevents, andgrid spacing; several iterations are per-formed to determine the source param-eters that produce synthetic seismogramsthat best fit the observed data. The focalmechanism from the Harvard CMT cata-log (311° strike, 26° dip, and 98° rake)and a trapezoidal time function (total timeof 6 seconds) provide the best fit to thedata. Using 12 P and 4 SH waves, theoptimal solution suggests a simple mo-ment release history, with primary mo-ment release approximately 10-20 kmnorthwest of the epicenter and second-ary moment release at the epicentral lo-cation and at ~40 km northwest of theepicenter (Figure 1). Depth of momentrelease occurs between 25-35 km. The

resulting source time function showsmoment release occurred within 20 sec-onds, with total moment release of2.8x1019 N•m, similar to the value pub-lished in the Harvard CMT catalog(3.0x1019 N•m).

We find that much of the moment re-lease during the October 2004 event oc-curred downdip of the rgional of largemoment release from the 1992 tsunamievent [Ihml, 1996]; moment release fromOctober 2004 does not overlap with the1992 rupture. Aftershocks recorded bythe TUCAN network occurrws primarilyin the region of high slip, with some lo-cated updip to ~15 km. The aftershocksclearly define the dipping thrust zone inthis region of Nicaragua. In summary,this data set reveals a fairly typical sub-duction zone thrust event that probablydefines the downdip end of theseismogenic zone near 35 km depth inNicaragua. This is somewhat deeper thanthe downdip limit of 26-28 km beneathnorthern Costa Rica near the Nicoya Pen-insula [DeShon et al., in press], indicat-ing that an important change in physicalproperties of the thrust zone may accom-pany the numerous other along-strikecontrasts between the two arc sections[MARGINS Science Plans, 2004]. Thiscollaboration also shows the value-addedcomponent of MARGINS studies: theTUCAN array was deployed to image thedeeper parts of the Subduction Factory,but clearly the data have relevance toSEIZE goals as well.

References

Abers, G.A., L. Auger, E. Syracuse, T. Plank,K.M. Fischer, C. Rychert, A. Walker, J.M.Protti, V. Gonzalez, W. Strauch, and P.Perez (2004), Imaging the subduction fac-tory beneath Central America: TheTUCAN Broadband Seismic Experiment,EOS Trans. AGU, Fall Meet. Suppl.

DeShon, H.R., S.Y. Schwartz, L.M. Dorman,A.V. Newman, V. Gonzalez, M. Protti, T.Dixon, E. Norabuena, and E. Flueh,Seismogenic zone structure along theMiddle America Trench, Nicoya Penin-

“Nicaragua” cont. on Page 22Figure 2. Cross section A-A’ showing relocated aftershocks, using arrivals from TUCAN.Cross section location shown on Fig. 1.

MARGINS Newsletter No. 15, Fall 2005

The Subduction Factory Initiative: Status and Future Directions -

October 2005Mark Reagan (Univ. of Iowa), Geoffrey A. Abers (Boston Univ.), Peter van Keken (Univ. of Michigan)

Initiative Summary

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SEIZE seismic station/OBSPermanent/long-termseismic stationTUCAN seismic stationCrustal imaging sourceGEOMAR seismic station, OBS and OBH deployments (Jaco, 4/02 to 10/02 and Quepos, 10/02 to 4/03)

Research funded by the Subduction Fac-tory Initiative (SubFac) addresses funda-mental questions about the mass flowthrough convergent margins and the rela-tive roles of mantle and subduction-de-rived constituents in building continen-tal crust. The fundamental science themesinclude: 1. How do forcing functions such asconvergence rate and upper plate thick-ness regulate production of magma andfluid from the Subduction Factory? 2. How does the volatile cycle (H

2O and

CO2) impact chemical, physical and bio-

logical processes from trench to deepmantle? 3. What is the mass balance of chemi-cal species and material across the Sub-duction Factory, and how does this bal-ance affect continental growth and evo-lution?

Focus sites for researching thesethemes were chosen by the communityto be the Central American and Izu-Bonin-Mariana (IBM) subduction zones(Figs. 1 and 2). Both have ample volca-nic and seismic activity, accessibility tosamples for geochemical analyses thatdocument inputs and outputs, along-strike variations in forcing functions,cross-arc and historical perspectives, andwide-ranging magma compositions. Cen-tral America has particularly dramaticvariations in forcing functions and lavacompositions along strike from Nicara-gua to Costa Rica. Extensive subductionof organic-carbon bearing siliciclasticand carbonate sediments beneath CentralAmerica enables investigation of the car-bon and water cycles through the sub-duction zone, from slab to surface. TheIBM margin complements CentralAmerica because it is subducting signifi-cantly older lithosphere covered by acrust with relatively thin and carbonate-free sediment. The presence of activeback-arc volcanism and fore-arc mantleserpentinization and fluid venting allows

output to be accessed across strike andthrough time.

The first SubFac integrative effort wasthe MARGINS-funded Theoretical andExperimental Institute (TEI) held at theUniversity of Oregon in 2000, with keycontributions published in the AGUMonograph “Inside the Subduction Fac-tory” (Eiler, 2003). This TEI and volumesummarize our understanding at the on-set of SubFac, and forms the baseline forprogress. In this interim report we willprovide an overview of research spon-sored by the Subduction Factory Initia-tive, focusing in particular on thegeochemical and geophysical field stud-ies at the two focus sites.

Mass fluxes through theCentral American arc

MARGINS-funded projects quantify-ing the input and output of the CentralAmerican arc have produced a numberof significant publications over the pastfew years. Studies of Li isotopes by Chanet al. (2002) and O isotopes by Eiler etal. (2005) have shown that Nicaraguanlavas, which have long been known tohave an exceptionally high proportion ofsubducted constituents (e.g., Carr, 2003),have a combination of heavy Li and lightO. This suggests that most of the trans-ported mass from the slab is in water-richfluids from subducting basaltic crust and

Figure 1. Major seismic experiments in the Subduction Factory/Seismogenic Zone CentralAmerica Focus Site. (Adapted from MARGINS Office Focus Site map available from:http://margins.wustl.edu/ResearchResults.html)


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Initiative Summary

serpentinized mantle. A deep source forthis water in subducted crust wasseismically imaged by Abers et al.(2003), and is consistent with both cal-culated seismic velocities for hydratedsubducted crust in the form of lawsoniteeclogite (or perhaps serpentinizedmantle) and seismic velocities predictedfor subduction zones (Connolly andKerrick, 2002). Pb isotope compositions(Feigenson et al., 2004), U-series and Thisotope data (Thomas et al., 2002), andvariations in O isotope values acrossCentral America (Eiler et al., 2005), to-gether with 10Be data (e.g., Morris et al.,1990) indicate that a separate water-poorcomponent derived from sediment alsois involved in magma genesis beneathNicaragua. Plank et al. (2002) estimatethat 75% of thorium from this sedimentconsistently has been recycled into lavassince 20 Ma, indicating at least 75% ofsediment subducts past the forearc.

Considerable advances also have beenmade in estimating fluxes of magmaticvolatiles out of Central American volca-noes. He-C relationships in gases fromfumaroles and hot springs indicate thatthe flux of carbon from the subductingslab to the surface increases from CostaRica to Nicaragua. This reflects the en-hanced sediment recycling beneath Nica-ragua compared to Costa Rica.Nevertheless, the total flux of carbonfrom the slab to the surface as CO

2 be-

neath Central America is about half thatof other arcs despite the high rate of sub-duction of carbonate and organic carbon,which implies that as much as 85% ofthe carbon in sediments subducts past theCentral American volcanic front to thedeep mantle (Shaw et al., 2003). Nitro-gen recycling from subducting sedimentis unusually low in the Costa Rican seg-ment of the arc compared to Nicaraguaand other arcs, and provides further evi-dence of weak sediment recycling be-neath Costa Rica (Zimmer et al., 2004).

Mass fluxes through theIzu-Bonin-Mariana arc

Volatile contents across the Izu-Bonin-Mariana arc are being investigated

in several novel ways. Studies of porewaters from serpentine mud volcanoes inthe forearc show that carbonate alkalin-ity, sulfate, Na/Cl, K, Rb, Cs, and B allincrease away from the trench as tem-perature increases at the top of the sub-ducting plate, suggesting that the depthof the 150°C isotherm in sediments be-neath the forearc is 17-22 km (Mottl etal., 2004). Studies of volatile concentra-tions and selected isotopic compositionsin glass inclusions in olivine crystals fromactive arc lavas are quantifying volatilefluxes through the IBM arc, as well ascompositions of endmember mantle-de-rived and subduction-derived compo-nents (e.g., Kelley and Plank, 2005; Shawet al., 2005; Fischer et al., 2005; Kentand Crowe, 2004; Kent and Gill 2005).Results suggest a role for decompression

melting of the mantle as well as fluid-fluxed melting to produce the lavas, andmay indicate carbonate contribution fromthe subducting altered oceanic crust.

Ongoing studies of compositions ofsubmarine glasses from the MarianaTrough and other back-arc lavas arequantifying the degree of involvement ofwater and other subducted constituentsin the backarc and the relative roles offluxed versus decompression melting(e.g., Kelley et al., submitted). Additionalconstraints on pressure, temperature, andH

2O content of magmas from the IBM

arc system are being determined throughexperimentation on natural samples (e.g.,Grove et al., 2004).

Geochemical studies of lavas eruptedthroughout the history of volcanism inthe Mariana arc are finding that the

Figure 2. Major seismic experiments in the Marianas portion of the Subduction Factory Izu-Bonin-Marianas Focus Site. (Adapted from MARGINS Office Focus Site map available from:http://margins.wustl.edu/ResearchResults.html)


“SF” cont. on Page 19

change from early boninitic volcanism tomore typical tholeiitic and calcalkalinevolcanism occurred over a several mil-lion year period, documenting the changefrom mantle upwelling at arc initiationcaused by catastrophic sinking of thePacific plate (Hall et al., 2003; Stern,2004) to normal mantle convection as-sociated with steady-state subduction(Reagan et al., 2003). In May 2004, Japa-nese and MARGINS-funded scientistsfrom the USA used the R/V Yokosukaand its Shinkai 6500 submersible to col-lect a late Eocene section ofvolcaniclastic rocks cropping out alongthe eastern escarpment of the OgasawaraTrough near the Bonin Islands (Bloomeret al., 2004; Ishizuka et al. 2005). Addi-tional diving by the same group to inves-

tigate the architecture of the arc crust andunderlying mantle southeast of Guam isscheduled for 2006.

Anatahan Event Response

MARGINS-funded scientists stagedrapid responses in May 2003 and March2004 to eruptions of Anatahan, the south-ernmost volcanic island of the activeMariana arc (see the reports in MAR-GINS Newsletters 12 and 14). Researchon samples and data collected on theeruption in 2003 is presented in a specialissue of Journal of Volcanology and Geo-thermal Research entitled: “The 2003Eruption of Anatahan Volcano, Common-wealth of the Northern Mariana Islands”(Hilton et al., 2005, see p. 22). Publica-tions of MARGINS-funded projects in

this issue included studies of seismicity(Pozgay et al., 2005), degassing (de Mooret al., 2005), and geochemistry of thelavas (Wade et al., 2005; Reagan et al.,2005). The principal implications of thesestudies from a volcano hazards perspec-tive are that significant eruptions ofandesite in arc volcanoes can be precededby very little seismicity, and that the dif-ferentiation from basalt to silicic andes-ite can happen in less than a few thousandyears. In addition, Wiens et al. (2005)were able to extract a rare tilt signal fromthe Anatahan seismic data, which they di-rectly related to magmatic inflation dur-ing the eruption. These studies also haveshown that Anathan’s andesite was gen-erated largely by crystal fractionation ofa parental basalt that was generated in themantle after it received about a third ofthe sediment that is presently subduct-ing beneath Anatahan.

Geophysical investigationsof the focus sites

Geophysical imaging complementsgeochemical studies of input and outputby providing in situ sampling of the Sub-duction Factory at work. Seismic andelectromagnetic measurements provideproxies for temperature, fluid abundance,the geometry of the main interfaces andtheir relationship to the generation ofearthquakes in the slab. Active-sourceseismic experiments also provide basicconstraints on crustal growth, tectonicevolution, and bulk composition of thecrust. At both focus sites, the nominalsuite of experiments include seismic re-flection images of the upper crust, large-offset imaging of the arc crust,earthquake-seismic experiments de-signed to image the subduction systemat mantle depths, magnetotelluric experi-ments designed to map out mantle con-ductivity structure, and heat flowmeasurements (Table 1).

In the Marianas, a joint U.S.-Japanproject is underway and provides a fullsuite of seismic measurements (U.S. PI’s:Taylor, Klemperer, Wiens). The projectincludes reflection imaging of fore-arc

Table 1 MARGINS-funded projects: The Subduction FactoryFocus P.I. Start End Short Title

GeochemistryCentam Carr 8/1/2005 7/31/2006 Volcanic growth rates

Centam Garrison 9/1/2004 8/31/2006 Rhyodacite differentiation

Centam Walker, Hirschmann 6/1/2004 5/31/2005 Centam magmas

Centam Carr 7/1/2002 6/30/2004 CentAm volcanic fluxes

Centam Eiler 8/1/2001 7/31/2004 CentAm O isotopes

IBM Goldstein 5/1/2005 5/31/2007 Eocene-Oligocene IBM

IBM Stern 6/1/2004 5/31/2009 IBM inputs

IBM Kent 7/1/2003 6/30/2006 Izu melt inclusions

IBM Hauri, Fischer, Hilton 6/15/2003 5/31/2006 IBM output fluxes

IBM Hanan, Hickey-Vargas,

Reagan

1/1/2001 12/31/2003 Early Marianas

IBM Grove, Stolper, Plank 9/1/2000 8/31/2003 IBM Volatiles

IBM Stern, Bloomer, Clift 9/1/2000 8/31/2003 IBM inputs

Gaetani 7/1/2001 6/30/2004 Hydrous melt experiments

Chan 9/1/1999 8/31/2002 Li isotopes

GeodynamicsHirth, Evans 5/15/2004 4/30/2007 Lithosphere rheology

Conder 7/1/2003 6/30/2005 Numerical melting models

Kerrick 6/1/2003 5/31/2005 Metamorphic devolatilization

Hirth 5/15/2002 4/30/2004 Mantle wedge convection

Van Keken 10/1/2002 11/1/2002 Workshop on subduction

zone thermal structure

Kincaid 8/15/2001 7/31/2003 3-D lab flow models

Kerrick 8/15/1999 7/31/2002 Metamorphic decarbonation

Geophysics and Marine GeologyCentam McIntosh 6/15/2005 5/31/2007 Nicaragua lakes reflection

Centam Holbrook, Lizarralde,

Kelemen, van Avendonk

11/15/2004 10/31/2009 CentAm crustal imaging

Centam Lonsdale 1/1/2003 12/31/2004 CentAm sea floor mapping

Centam Brown 5/1/2002 12/31/2004 CentAm benthic fluxmeter

Centam Abers, Fischer 4/1/2002 3/31/2006 CentAm broadband seismic

Centam Fisher, Stein, Harris, Wheat 10/1/2000 9/30/2004 CentAm marine heat flow

Centam McIntosh, Silver 1/1/2000 12/31/2002 CentAm marine reflection

IBM Chave 6/1/2004 5/31/2008 IBM Magnetotellurics

IBM Fouch 7/1/2003 6/30/2005 IBM anisotropy and flow

IBM Taylor, Wiens, Klemperer,

Hildebrand

10/1/2001 9/30/2005 IBM multi-scale seismic

MARGINS Newsletter No. 15, Fall 2005 Meetings Update

Waipaoa Source to Sink Participants Hold

Science and Planning MeetingsClark Alexander, Phil Barnes, Kelvin Berryman, Kate Bodger, Hannah Brackley, Lionel Carter, Lila Gerald,

Tommy Gerber, Steve Kuehl, Nicola Litchfield, Jesse McNinch, Alan Orpin, Alan Palmer, Jarg Pettinga,Lincoln Pratson, Noel Trustrum and J.P. Walsh contributed data to this summary of Waipaoa research pre-

sented at the New Zealand Marine Sciences Society MARGINS session.

Within the MARGINS Program, theSource to Sink (S2S) Initiative is foster-ing greater understanding of completesedimentary systems, extending fromupland sediment sources to deep-seasediment sinks. The Waipaoa Sedimen-tary System (WSS) located on the eastcoast of the North Island, New Zealand,is one of two S2S focus sites, and sawMARGINS-funded field work begin onthe continental margin in January andFebruary 2005 (see focus area map andstudy regions at the MARGINS Website< m a r g i n s . w u s t l . e d u / R e s e a r c hResults.html>). Because of the solid sci-entific background developed by NewZealand researchers in the area and theinitial cruise observations and measure-ments, significant new insights into theWSS are already beginning to be avail-able and strategic planning based on theseresults is ongoing. These results are be-ing disseminated beyond the individualinternational MARGINS collaborators atinternational conferences and througheducational websites (e.g., http://coastal.geology.ecu.edu/nz/index.php).

In August 2005, results from theWaipaoa focus site were presented at theinternational “Human Impacts in the Ma-rine Environment” meeting run by theNew Zealand Marine Sciences Societyin Wellington, NZ. Julie Morris of the USMARGINS Office opened the dedicatedsession by giving an overview of theMARGINS Initiative. Steve Kuehl (Vir-ginia Institute of Marine Science - VIMS)presented the Keynote talk in the session,introducing the MARGINS S2S Initia-tive and the specific characteristics of theWSS that make it a highly suitable sitefor addressing S2S research questions. Tostart off the disciplinary session, ChuckNittrouer summarized the state of knowl-edge for the second S2S Focus Site, theFly River/Gulf of Papua, Papua New

Guinea, so that details of the WSS pre-sented later could be compared and con-trasted, in line with the MARGINSphilosophy.

Major sources of new data for theWSS included two cruises to the Waipaoamargin in January and February 2005 onthe RV Kilo Moana, focusing on shelf andslope sedimentary processes, respec-tively. Radiochemical and sedimentologi-cal results confirm the presence of threemodern sediment depocenters on theshelf: two on the midshelf, one north andone south of the river mouth; and a thirdon the outer shelf that had been previ-ously identified. In each of thesedepocenters, accumulation rates approxi-mate 1 cm/y. Interestingly, the strati-graphic character of the depocentersdiffers such that the midshelf depocenterspreserve physical stratification and ter-rigenous input signals, whereas the outershelf depocenter is more homogeneous.Modern sediment is also escaping theshelf to accumulate in some submarinecanyons on the upper slope, at rates simi-lar to those in the shelf depocenters. Al-though sedimentary organic matter isdischarged from the river along with thelithogenic particles that transit the mar-gin, there is a depletion in terrestrial or-ganic carbon seaward across the marginand a commensurate increase in marineorganic carbon content. Dispersal mecha-nisms through the WSS are still poorlyunderstood and require additional studyto identify relevant sources of materialto and transport pathways within thestudy area.

Upcoming MARGINS fieldwork todocument shoreline progradation andsediment exchange between the coastalplain and inner shelf has recently beenfunded by NSF and will extend the in-vestigation of the WSS from the conti-nental slope across the land/sea boundary.

As the study moves up into the drainagebasin, increasing knowledge of the influ-ence of tectonic setting on sediment sup-ply (e.g., via tectonic erosion, regionaltilting and nickpoint retreat) will growin importance.

The session ended with a compara-tive discussion of the Waipaoa and Flysystems, drawing on the new results pre-sented earlier in the day and the pre-ex-isting information that initially identifiedthe WSS as an appropriate S2S FocusSite. Several characteristics were com-mon to all potential focus sites, includ-ing: a closed system; strong forcingproducing strong signals; active sedimen-tation within and transfer between com-partments of the dispersal systemsproducing a high-resolution record; ad-equate background data and infrastruc-ture; and manageable logistics. Inaddition, the WSS exhibits characteris-tics of: a strong upland input signal fromnatural sources, particularly earthquake-triggered landslides, and anthropogenicsources (i.e., European colonial defores-tation); strong cyclonic meteorologicalforcing and basin response; a well-con-strained point source for input of this flu-vial material to the sea; frequent andspatially extensive volcanism that pro-vides outstanding geochronological con-trol through uniquely identifiable andwell-dated tephra horizons; and signifi-cant lake and paleo-lake deposits contain-ing records of climatic and tectonicactivity spanning the past 30 ka, whichcan be compared to continental marginsedimentation over the same time period.The WSS was also characterized as ananalogue to the Eel River System in theUS, which will be the proposed site of aMARGINS S2S TEI in late 2006.

The day following the open scientificsession, the National Institute of Waterand Atmospheric Research (NIWA)


hosted a one-day workshop at their GretaPoint facility to assess the state of theWaipaoa S2S Initiative and to identifygaps in the Science Plan based on dis-cussions from the previous day. Presen-tations were made highlighting theprogress and goals for each of the fourS2S sectors (i.e., uplands source, floodplain/coast transition, continental shelfand continental slope sinks).

For the uplands source, much is al-ready known from previous researchabout shallow landslide and gullying pro-cesses, although the timing and durationof these processes are less well under-stood. The major issues for source termfield researchers and modelers is the char-acter and timing of major landslides:How often do they occur? Do they pro-vide a pulse, steady perturbation or apost-event pulse that moves through thesystem? How do they affect sedimentdelivery? This information will becomeeven more critical when extending thetimescale of interest to the Last GlacialMaximum (LGM) and beyond, as the cli-matic conditions change significantly.

Work has only recently been fundedto investigate the region of the floodplain/coastal transition. The major goals withinthat sector will be to more precisely de-termine coastal progradation history, todetermine the effect of natural and hu-man changes in the river geometry andto prepare for and carry out rapid re-

sponse cruises to better understand thedispersal of material from Poverty Bayonto the shelf.

The continental margin, specificallythe shelf and slope sectors, have beenresearch foci in the past year. Identifi-cation of discrete shelf depocenters, someof which are preserving a terrestrial sig-nal, illustrates the need for longer coresin the three depocenters and an under-standing of biological markers in therecord (i.e., palynomorphs, microplank-ton and organic carbon). Additionally,analysis of existing sidescan data needsto be performed to help determine shelftransport pathways. For the slope sector,discovery of significant off-shelf trans-port to the upper slope highlights the needto understand circulation and transportprocesses near the shelfbreak. With sig-nificant material accumulating on thecomparatively steep slope, the roles ofmass wasting and lower slope sedimenttransport also need to be addressed.

As illustrated by the discussion above,the gaps in our current science plan forall four of the sectors in the WSS focuson two topics: tectonics and transport.Although these two topics are relevantto all four sectors of the WSS, differentspecific needs exist within each sector.For all sectors, a thorough understand-ing of the detailed tectonic history of theWaipaoa drainage and margin is neces-sary in order to unravel the signatures of

sediment supply, changing basin geom-etry and shelf/slope mass wasting. Forthe upland sector, filling gaps requires asynthesis of existing terrace age datasetswith other existing paleorecords, the pro-duction of river discharge histories inrelation to changing climate and land-scape, and a synthesis modeling effort.For the floodplain/coastal transition, shelfand slope sectors, filling gaps will requireboth observations and modeling of cir-culation and sediment transport processesat the coast and on the continental mar-gin.

During general discussions, the groupwas apprised by Geoffroy Lamarche thatthe French RV Marion Dufresne II wouldbe in NZ waters in January 2006. Thisship is capable of retrieving piston coresup to 58 m long, which could provideopportunities to examine the LGM sedi-ment record on the slope and shelf. It wasagreed that Kuehl and Alexander wouldwrite supplemental proposals to NSF topursue this opportunity, requesting sup-port to collect 5 cores, one from each ofthe shelf depocenters and two from theslope (for which funding has subse-quently been awarded). In addition, aconsensus was reached to quickly de-velop an event response plan for theWSS, to be executed in the event of acyclone during the MARGINS study pe-riod.

MARGINS Rupturing Continental Lithosphere Workshop

“Lithospheric Rupture in the Gulf of California-Salton Trough Region”

Ensenada, Mexico, January 9-13, 2006

After receving enthusiastic international response, the final stages of planning are currently progressing for this MAR-GINS-sponsored workshop to be held January 9-13, 2006, in Ensenada, Mexico. The workshop will focus on lithos-pheric extension, crustal deformation, seafloor spreading, magmatism, basin formation, and upper-mantle processesthat ave operated through time to shape the active oblique-rift system of the Salton Trough Region.

Although applications closed a couple of months ago, post-meeting additions to the workshop website (www.rcl-cortez.wustl.edu) will include: presentation PowerPoints; a workshop report; and information on major outcomes ofdiscussion on synthesis and future directions.

Workshop abstracts will also soon be posted on the meeting website.


It’s with a certain sense of irony that Inote two things affecting MARGINS,which are happening almost simulta-neously. MARGINS science is floweringacross all the initiatives, and synthesiswork within each of the focus sites is wellunderway. At the same time, flat funding± at NSF together with increased fuelcosts and the retirement of the R/V Ewingis significantly limiting continuing MAR-GINS research as MARGINS heads intoits seventh year of funding. I’ll talk aboutthe status of the initiatives in a minute,but let me turn first to the funding situa-tion as I understand it.

NSF Funding Levels

The increasing cost of ship operationsmakes the Ocean Sciences Division par-ticularly vulnerable to the negative im-pacts of flat funding. In an attempt to dealwith this issue, NSF asked UNOLS toprepare a series of recommendations fortheir consideration (see www.unols.org,UNOLS Recommendations on how toAddress the Impact of Declining BudgetLevels on Fleet Operations). The reportclearly notes that budget cuts severelylimit researcher access to the sea and arehighly detrimental to effective research.That said and universally agreed, the re-port contains a series of recommenda-tions. One is intended to keep ships andcrews together and functioning as muchas possible through partial rather thantotal lay-ups. Another is to continue de-veloping new capability for the fleet (e.g.,complete the refitting of the R/VLangseth, with its 3-D seismic capabil-ity), but slow the pace of development tospread costs over additional years. A con-sequence for MARGINS researchers isthat high quality and important propos-als may be declined or ship time with-held until further in the future. From mydiscussions with program officers andvarious PIs, I believe that investigatorsin core programs and other special ini-tiatives such as R2K are sharing the same

fate.Are there any bright spots or solutions

for MARGINS? I’m afraid that we’re infor at least several more lean years, whichwill require patience and persistence. TheU.S. Commission on Ocean Policy Re-port (www.oceancommission.gov), de-livered to the President and Congress lastyear, highlights many aspects of mostlyapplied research that are important to thehealth and well-being of the oceans andthe country. Among these are hazards andresources, which have been explicit partsof the MARGINS Science Plans from theget-go. While our focus will not be onmapping hazards or quantifying reserves,any number of relevant topics grow outof our science (e.g, investigations ofearthquake triggering and fracture propa-gation mechanisms by the SEIZE initia-tive). It’s perhaps worth asking your NSFprogram officer about the level of inter-est in proposals that include hazards orresources. More importantly, all of theinitiatives are ripe for more theoreticaland experimental investigations. TheMARGINS panel has always recom-mended these types of proposals, but nowmay be an especially good time for fi-nancial reasons (reduced ship time) andto make use of the large amount of sci-ence now becoming available from ear-lier MARGINS funding. In addition to amore integrated understanding of theproblem at hand, such efforts could high-light the essential missing data types nec-essary to resolve critical issues.

NSF-MARGINS Panel

You may know that as MARGINSChair, at NSF invitation I have presentedbrief summaries of MARGINS activitiesbefore the start of last two MARGINSpanels, without any knowledge of theproposals submitted or their content. Mypresentations have been based on MAR-GINS Steering Committee (MSC) dis-cussions, information provided by thePIs, and what I learn through attending

workshops and special sessions. As such,my viewpoints are informed, but alsoshaped by the perceptions and judgmentsof the MSC and myself. However, theseform only a small part of the input thatthe panel and program officers receivefrom multiple sources, which they weighand use as they see fit. As backgroundfor the panel, we update the MARGINSfocus area maps (www.margins.wustl.edu/ResearchResults.html) and compilelists of funded proposals in each of thefocus areas, together with their abstracts(published in the Spring Newsletter eachyear and available at www.margins.wustl.edu/NSF-MARGINS/AwardNum.html).In the presentation itself, I present a fewsnippets of new science in each of theinitiatives, culled from what you provide,what I see at meetings or in journals, andwhat comes to the MSC. I also summa-rize recognized research gaps in each ofthe initiatives and highlight upcoming ac-tivities. The research gaps are those iden-tified by the MSC in preparation for theNSF-MARGINS review last year(www.marginsreview.wust l .edu/InitiativeSumm.html, and look for thesubsection headed Research Gaps),modified by the publicly available infor-mation about proposals funded since thattime. Two articles in this Newsletter(SubFac Initiative status and future di-rections, p. 3; and a report on S2S NewZealand science and planning meetings,p. 6) speak to this topic, and are discussedbelow. I iterate all this for several rea-sons: I believe in transparency; I want toencourage your cooperation in updatingthe MARGINS Office and MSC on yourresearch accomplishments; and I want togive you the opportunity to let the MSCknow if you feel that having the Chairspeak to the MARGINS panel is inap-propriate. However, I’m completely con-fident in myself that this is an extremelyuseful activity, is well appreciated by theNSF panel, and violates no confidential-ity, but I’d like to hear from you

From the MARGINS Chair - Fall 2005Julie Morris, Dept. of Earth and Planetary Sciences, Washington University in St. Louis, MO 63130, USA

E-mail: [email protected]

From the Chair


([email protected]) if you thinkdifferently.

Status of the Initiatives

We began including a regular updatein the Newsletter on the status of the ini-tiatives a year ago. Our reasoning is thatyou should also hear the discussions onhow work is progressing in each initia-tive that are available to NSF programofficers. Each Newsletter, a subset of theMSC is asked to write a short article onprogress within an initiative, and we ro-tate through the four areas of study.

Subduction Factory. A substantive ar-ticle in this Newsletter reviews progressin the SubFac Initiative (see p. 3). Sincethe NSF-MARGINS review of a yearago, proposals have been funded for ac-tive and passive source seismic studiesof Central American crustal structure, andfor additional studies of the incomingplate, with work well underway. Studiesof hydration of the shallow incomingoceanic plate off Costa Rica are under-way through ODP Leg 205 and IODPExpeditions 301T and 312. Amagnetotelluric study of the IBM systemwill commence in Dec. 2005. As notedpreviously, most of the big-ticket marinesurveys have now been funded and par-tially completed for the SubFac Initiative.Observationally, modern systematic heatflow studies that extend across the arcremain to be done, along with furtherstudies of magma and volatile fluxes andselected petrological and geochemicalstudies. Conceptually, topics such as ini-tiation of subduction, development of theintrusive part of the arc system, and theextent of serpentinization of the deep partof the incoming plate are becoming in-creasingly important. As noted by theMSC, integration and synthesis and theo-retical modeling are now very high pri-orities for SubFac; the AGU specialsession on the IBM system (Izu-Bonin-Mariana Subduction Factory Studies,T44A, T53A) is a step in that direction.

Seismogenic Zone. The SEIZE experi-ment is also progressing nicely, withIODP proposals for riser- and riserless-drilling off Nankai and off Costa Ricamoving through the advisory structure.

A joint Japan-US study will carry out 3-D seismic work in the Nankai region in2006. In 2004, a proposal was funded toestablish a sparse continuous GPS back-bone for Central America.Observationally, a long-term OBS de-ployment remains to be done in CentralAmerica. The MSC notes the importanceof additional laboratory studies of mate-rial properties, frictional heating,physico-chemical processes for rate-de-pendent friction, consolidation and meta-morphism, and theoretical orexperimental studies of earthquake nucle-ation and propagation. Another very im-portant topic is thermal modeling andintegrated thermal-hydrological, -chemi-cal, and -deformation modeling, includ-ing temporal variations through theseismic cycle. The MARGINS specialsession at AGU (Fluids at SubductionZones: Integrating Models and Observa-tions Within MARGINS and RelatedStudies, T11E, T12B, T13B) speaks tosome aspects of this topic.

Rifting of Continental Lithosphere.Much of the observational work plannedfor the Gulf of California (GoC) site isunderway or nearing completion and willbe presented at a MARGINS workshopin Ensenada, Mexico, Jan. 9-13, 2006,convened by Becky Dorsey, Raul Castro,John Fletcher and Dan Lizarralde. Oct.2005 saw installation of a 15 month OBSdeployment in the GoC. Beyond what hasalready been done, there is currently noactive source seismic work for the north-ern Gulf, a result of marine mammalcomplications. High-resolution seismicwork is needed in the S. Gulf. Some as-pects of the neo-tectonics remain to beworked out, along with the extended his-tory of rifting in the region (12-13 Myrhistory, and locally as long as 15-20 Myrhistory). At the workshop in January, oneunderlying goal will be to evaluate thecomplete package of achievable work inthe region (taking into account permit-ting issues) and assess the quality andimport of the science that can be accom-plished. Another concern will be to inte-grate as much as possible withEarthscope efforts in adjoining regions.The great beauty and natural significance

of the Gulf of California was recentlyformally recognized in the creation of theUNESCO Islands and Protected Areas ofthe Gulf of California World HeritageSite (http://whc.unesco.org/en/list/1182).We hope that this designation will in-crease public, visitor and governmentinterest in understanding the history andorigins of the region’s unique features,but also recognize that it remains criticalthat researchers not only maintain aware-ness of enviro-political concerns, but alsobe conspicuously seen to do so.

In the Red Sea, a Euro-MARGINScruise in Dec. 2004 - Jan. 2005, withEnrico Bonatti as chief scientist, was ableto do some bathymetry mapping anddredging in the central region. US fundedefforts include a thermochronology studyin Saudi Arabia, a GPS study in SaudiArabia and Eritrea, with stations to bedeployed in Egypt soon, and a tomo-graphic study using results from Saudiseismic stations, IRIS permanent stationsand a 1996 PASSCAL deployment.Source to Sink. S2S investigators aremoving very quickly in both the Gulf ofPapua (Papua New Guinea) and Waipaoa(New Zealand) focus areas. An extensivearray of coordinated cruises was carriedout in Papua in 2004 and in the Waipaoaregion earlier this year. Results have beensummarized at a number of special ses-sions at GSA 2004, AGU 2003 and 2004,and the New Zealand Marine Conference2005, with upcoming sessions at the 2006AAPG meeting and AGU Ocean Sci-ences meeting. Specific progress and re-search needs for the Waipaoa region arenicely summarized in the article entitled“Update on Waipaoa Source to Sink Sci-ence and Planning Meetings” on p. 6 ofthis Newsletter. Recent work in Waipaoahighlights the importance of tectonicsedimentation in the region, and the ex-istence of long stratigraphic records onland and at sea of changing climate andtectonic conditions, well constrained bytephrochronology. In the Gulf of Papua,work continues on topics such as the sedi-ment fluxes from the Fly River vs. the

“Chair Report” cont. on Page 21


Over the last decade NSF has sponsoredseveral workshops of the sediment dy-namics and sedimentary geology com-munity to develop a unified vision for thecreation of a surface dynamics modelingsystem with the capability to predict theerosion, transport and accumulation ofsediments and solutes from the source ofthe sediments in the uplands to their ulti-mate sink in the deep sea. The commu-nity has concluded that they need to de-velop a community wide surface-dynam-ics modeling “environment” containinga suite of interconnected and integratedsoftware modules capable of predictingthe transport and accumulation of sedi-ment and solutes in landscapes and sedi-mentary basins over a broad range of tem-poral and spatial scales. The science planof the MARGINS Program’s Source-to-Sink initiative underscores this need andadvocates a community sediment mod-eling effort that deals with the source tosink system of environments in its en-tirety. On-going MARGINS experimentsmay provide the necessary observationalunderpinnings for testing the resultantsystem of integrated models. An earlier“Future of Marine Geology and Geo-physics” report of the Earth Science com-munity to NSF also decried the lack oflinkages between models dealing withvarious components of the system andidentified this as a major barrier to theadvancement in surface processes re-search. The report strongly recommendedthe development of integrated sedimentmodels at a range of time scales involvedin surface processes, covering all sedi-ment features and morphologies by a se-ries of linked models into a unified wholethat would lead to a general theory ofsedimentation based on the fundamentalprinciples. Supporting documents forthese recommendations can be found infollowing websites and reports:• The Community Surface-DynamicsModeling System Strategy and Rationale

http://instaar.colorado.edu/deltaforce/workshop/version4_04.pdf• Community Surface-Dynamics Model-ing System Science Plan

http://instaar.colorado.edu/deltaforce/workshop/CSDMS_science_ plan_v6.pdf

• Community Surface-Dynamics Model-ing System Implementation Plan

http://instaar.colorado.edu/deltaforce/workshop/CSDMS-implementation-final.pdf

• “The Future of Marine Geology andGeophysics” Report of a workshop toNational Science Foundation, pp. 47-70,1997.

• “MARGINS Science Plans, 2004” pp.131-157, also available on website of theMARGINS Program

http://www.marginsreview.wustl.edu/SPHome.html

In response to these needs and com-munity recommendations NSF will ac-cept proposals from the community forjoint consideration by the Divisions ofEarth and Ocean Sciences for the estab-lishment of an organizational infrastruc-ture (OI) to be considered within theirexisting GeoInformatics (administeredby the Instrumentation and Facilities Pro-gram) (GI) and MARGINS Program so-licitation frameworks, respectively.

The organizational infrastructure (OI)will form a nucleus responsible for theconstruction of the overarching architec-ture of the surface-dynamics modelingenvironment and must meet several chal-lenges that include: a multiplicity offields, scales, interests and applications;a central role of testing the modulesagainst data; the coverage of a widebreadth of surface processes; productdelivery in a timely manner; and nationalcommunity reach. It will house the coreserver and some of the essential manage-ment, computational and educationalstaff necessary to advance the CSDMS

initiative. Other active participants maybe distributed elsewhere in other institu-tions.

It is envisioned that the OI will be re-sponsible for: 1) Creating and maintain-ing the computational system, 2)Ensuring compatibility, portability andinteroperability of modules, 3) Ensuringclarity/consistency of documentation,interfaces, code, 4) Ensuring computa-tional efficiency of system code, 5) Sup-porting working groups/nodes andindividual scientists with on-site and off-site (virtual) training, topical workshops,and other meetings, 6) Linking to othernational computational resources, and 7)Education and knowledge transfer to thecommunity and public. The OI may alsopropose demonstration project(s) vital totheir overall mission.

The OI will also have a central role inenabling working group nodes that willrepresent the knowledge base, and willbe responsible for creating and manag-ing the various process modules and pro-viding continuity to meet long-termproject objectives. The working groupswill be set up to solve integrated prob-lems outlined in the science plan, iden-tify gaps in knowledge, and fosterinter-disciplinarity within and betweengroups. As “keepers of the code” thesegroups will identify the tools and/or pro-cesses that populate the various disciplin-ary toolkits. They will be responsible forquality control for the algorithms andprocesses that are included for their areaof expertise. They will set the prioritiesfor modeling within a discipline, and fa-cilitate the movement of these prioritiesup the hierarchy from technology groupsto OI and the Steering Committee. Thus,the responsibilities of the working groupsinclude: technical quality control; ad-equacy of testing; evaluating the codesaccording to interoperability criteria; set-ting scientific priorities for the group;

N.S.F to accept Proposals for the Development of “CSDMS”

Organizational InfrastructureBilal Haq, National Science Foundation

“CSDMS” cont. on Page 22

CSDMS


This summer, Dr. Rosemary Hickey-Vargas enthusiastically agreed to serveon the newly formed MARGINS Educa-tion and Public Outreach (MEPO) Com-mittee. As a MARGINS scientist who hasshown her mettle in the field of educa-tional outreach and as a Subduction Fac-tory Principal Investigator (PI), we weredelighted when she agreed to be inter-viewed for this edition of the MARGINSNewsletter.

A long-timeinvestigator ofconvergent mar-gin magmatism,Rosemary star-ted as a facultymember at Flor-ida InternationalUniversity (FIU)after completingher doctorate andpost- doctorate atMIT. From 2001to 2004 she wasFIU DepartmentChair. Her NSF-Geosciences fun-ded research hasespecially focu-sed on the earlyIzu-Bonin-Mar-ianas (IBM) Arcand the southernAndes, includinga recently com-pleted MARGINS-funded collaborativeresearch project: OCE 00-01826: Magmageneration in the early Mariana Arc sys-tem revisited, with co-PIs Mark Reagan(U. Iowa) and Barry Hanan (San DiegoState).

Having a son in Miami public educa-tion is what first drew Rosemary intoexpanding her outreach activities. See-ing how he benefited when other scien-tists and professionals made the effort tocommunicate with his school and teach-

ers inspired her to run an annual onlinegeoscience contest for local high schoolscience students during AGI’s Earth Sci-ence Week. That was 1998, and the con-test is still running. As FIU DepartmentChair, the practical motivation to recruitnew geoscience majors further openedher perspective on outreach opportuni-ties.

It was during Rosemary’s term as De-

rel Collins, Michael Gross, AndrewMacfarlane, Rene Price and DeanWhitman.

These faculty recognized that manyincoming undergraduates overlook theFIU geoscience major simply becausethey have not been exposed to the diver-sity of the field, or do not know that itcan open up a range of relatively highpaying, socially useful careers. Thus

GeoSCOPEwould focuson attractingscience-ori-ented fresh-man andsophomoresfrom under-representedgroups intothe geoscien-ces at FIUand MiamiDade Com-munity Col-lege.

Each sum-mer, the pro-gram openswith aroundtwenty in-terns, drawnfrom sciencecourses, par-ticipating inshort two-

week faculty-taught workshops that (cru-cially) bring them up to speed ongeoscience topics and research methods.These workshops lead directly into in-ternships working in research labor-atories in the FIU Earth SciencesDepartment for about six weeks. At theend of the internships, a dedicated sym-posium allows the interns to present andshare their research results from acrossthe breadth of GeoSCOPE faculty spe-cializations. The program also brings lo-

EPO Spotlight: Rosemary Hickey-Vargas,

Principal Investigator of GeoSCOPEPaul Wyer interviewed Dr. Rosemary Hickey-Vargas, Florida International University

partment Chair that she and other facultypooled their experiences with FIU stu-dents, and assembled an ambitious NSF-OEDG (Opportunities for EnhancingDiversity in the Geosciences) proposalfor “GeoSCOPE” (Geo Science CareerOPportunity Exploration). Funded in2003 for three years, the project currentlyinvolves eight department faculty, withRosemary as Principal Investigator. Theother faculty are co-PI Grenville Draperand co-investigators Bill Anderson, Lau-

Two GeoScope interns melt rocks for entertainment, science, experience, and a living

EPO Spotlight


cal high school science teachers in for asummer workshop that engages them inexciting, cutting edge research that theycan take back to their classes.

A dedicated website acts as an onlineresource for those interested in learningmore about the program, internships andteacher workshops: www.fiu.edu/orgs/geology/template2/geoscope/

At a time when minority students canstill choose to pursue a major or gradu-ate geoscience degree, GeoSCOPE raisestheir awareness of the opportunities thatthe subject offers. There is certainly noshortage of interested students at FIU,where the undergraduate community isroughly 52% Hispanic, 21% white/non-Hispanic, 15% African-American, 3%Asian, and 1% Native American. Thedemography of Miami-Dade County,where FIU is situated, is similar, ensur-ing a comparable impact for outreachaimed at local high school teachers.

As is essential for any such project,the success of GeoSCOPE is bench-marked in a systematic way, in this casevia carefully structured questionnairesreturned by the student participants at theend of their internships. From the feed-back received thus far, Rosemary and hercollaborators appear to be making a tan-gible impact, with most students enjoy-ing the experience and stating that it hasimproved their understanding of geo-science and likelihood of pursuing a sci-entific career. Notably, one intern wenton to get a McNair Fellowship forpaleobiological research, and anothernow has a Florida Georgia LSAMP(Louis Stokes Alliances for MinorityParticipation) Fellowship in physics.

At two years in, a GeoSCOPE-drivenpath from internship to geoscience ma-jor is not yet evident, but may becomeclearer as students encounter contempo-rary pressures on other science majors,or at the graduate level. About 10% ofGeoSCOPE interns to date have eitherbecome geoscience majors or intend toapply to geoscience graduate programsafter completing other science degrees.Even for those who don’t go on to a geo-science career, the program providesthem with paid research that broadens

their experience and supports theircompletion of college.

At FIU, the graduate students alsobenefit from their work alongsideGeoSCOPE interns, especially when theinterns bring in mutually beneficial com-puter, math or other technical skills. Asfor the participating faculty, the programallows them to work and interact withundergraduates at a research level, po-tentially furthering their own researchgoals in the process.

By way of example, Rosemary’s ownSubduction Factory research has directlybenefited from the program. In supportof her MARGINS-funded research on theIzu-Bonin-Marianas Arc, two under-graduate majors and two interns collec-tively processed glass and mineral shardsfrom a volcaniclastic sediment sequence,and were able to present their results atthe Spring 2005 AGU Joint Assembly.Her most recent interns worked along-side two graduate students, igniting andfusing rock powders (they greatly en-joyed informing their peers about “melt-ing rocks for a living!”), and runningmajor element analyses in support of anNSF-EAR funded project.

From a personal perspective, how-ever, Rosemary finds the greatest rewardsare her interactions with interns andteachers, especially at that moment ofunderstanding when the meaning andscope of what “geoscience” can be sud-denly become clear.

Asked what aspects of runningGeoSCOPE are harder or easier thanoriginally expected, Rosemary’s first re-sponse is that the enthusiasm of the in-terns goes a long way, and is part of whatmakes the program such a rewarding ex-perience. By contrast, the most difficultaspect has been the administrative over-head that comes with recruitment, regis-tration, finances and symposia for aroundtwenty interns and the high school teach-ers the project serves. Rosemary suggeststhat budgeting for a non-scientist coor-dinator from the start would have been agood way to take these burdens awayfrom the participating scientists.

From Rosemary’s viewpoint, the keyto obtaining support and making a suc-

cess of an education or outreach programis to demonstrate that it will make animpact on the target group (K-12, teach-ers, general public, etc.) in a way thatcomplements the research activities of theproponents. That way, proponents guar-antee not only to NSF that they have theexpertise needed to guide the participantactivities, but also to themselves that theproject will have a facet that they willespecially enjoy. Rosemary notes that anyNSF proposal submission can benefit byincluding specific elements addressedthrough education or public outreach, andthat activities can also be appended toexisting proposals through the NSF-REU(Research Experiences for Undergradu-ates) program.

In meeting and communicating withRosemary by e-mail, what really comesthrough is her enthusiasm and imagina-tion when it comes to opportunities formaximizing the benefits of outreach. Theexpertise and energy she brings to theMARGINS Education and Public Out-reach Committee are greatly appreciatedby the MARGINS Chair, Steering Com-mittee and Office. With the input that sheand the rest of the EPO Committee pro-vide, and a proposal for a communityworkshop on the subject in preparation,we look forward to development of astructured plan for education and out-reach objectives across the breadth of theMARGINS Program. We expect Rose-mary to be a key contributor along theway.

There are many ways to obtain fund-ing from NSF for undergraduate re-search: GeoSCOPE’s funding camefrom a natural synthesis with OEDG(Opportunities for Enhancing Diver-sity in the Geosciences), which is, “de-signed to address the fact that certaingroups are underrepresented in thegeosciences relative to the proportionsof those groups in the general popula-tion.” GeoSCOPE has benefitedgreatly from advice provided by thesponsoring OEDG Program Officers:Dr. Jewel Prendeville initially, and lat-terly Dr. Jacqueline Huntoon.

EPO Spotlight

MARGINS Newsletter No. 15, Fall 2005 AGU 2005

Sessions Related to MARGINS Science

at the Fall 2005 AGU Meeting

The diversity and range of MARGINS research and goals make it increasingly difficult to select a shortlist that captures all AGUsessions of special interest to the MARGINS community. However, comments from last year suggest that - although not comprehen-sive - the list and brief summaries (derived from the full abstracts on the AGU website: www.agu.org/meetings/fm05/) can be a handyguide to have at the meeting.

AGU Code Key: Section: Day of Week (1-5): Session Time (1X-2X: 08:00 and 10:20; 3X-4X: 13:40 and 16:00). E.g., T11E =Tectonics, Monday, Session 1E (13:40). Please refer to the AGU meeting program to verify session times and locations.

MARGINS SessionsT: Fluids at subduction zones: Integratingmodels and observations within MAR-GINS and related studiesPore fluids and fluid flow play defining rolesin subduction zone processes, over a widerange of depths and scales. Such processesinclude rock diagenesis and alteration, faultzone stability and seismogenesis, upper andlower plate deformation, dehydration reac-tion in downgoing crust and mantle, magmaformation and migration, dynamics of themantle wedge, and earthquake nucleation.For this reason, characterizing the occurrenceand role of fluids at subduction zones hasbeen a key component of both theSeismogenic Zone Experiments (SEIZE) andSubduction Factory (SubFac) Initiative of theNSF MARGINS Program. Unfortunately,direct observations of fluids and fluid pro-cesses have been limited. Further progressin understanding the role of fluids can begained from integrated fluid flow, thermal,chemical, and deformational modeling, cali-brated by observations and measurements ofsubduction zone processes and properties.This session is intended to bring numericalmodelers together with those who collect andinterpret geophysical, geodetic, seafloor, anddrilling data relevant to subduction zone flu-ids. T11E, T12B (MCC 3011), T13B (MCCLevel 1, 0453-0481).

T: Izu-Bonin-Mariana Subduction FactorystudiesThe Izu-Bonin-Mariana (IBM) system is per-haps the best-studied example of an intra-oceanic arc and a primary focus region forsubduction factory studies in the MARGINSprograms of several countries. Recently ma-jor advances have been made in understand-ing the geological history and geochemicalcycling of the IBM system, and revealing thecrust and mantle structure of the IBM arc andbackarc. These results have important impli-cations for understanding subduction zone

dynamics, mantle flow and magma produc-tion in arcs and backarcs, and the formationof arc crust. This session will be comprisedof papers on IBM subduction zone studies,including the formation of arc magma andcrust, studies of the geological history or cur-rent tectonics of the arc, constraints on geo-physical structure and mantle flow, and mod-eling studies with implications for the IBMsystem. T44A (MCC 3024), T53A (MCCLevel 2, 1393-1416)

Sessions relevant toMARGINS scienceED: Integrating education and outreachwith large-scale experimentsLarge-scale, long-term experiments, such asEarthScope, Cassini, and IODP, frequentlycapture the public’s imagination, providingunique education and outreach opportunities.This session focuses on such efforts and thespecial issues inherent to large scale experi-ments, with emphasis on developing andmaintaining high levels of public interest andinteraction. ED11E (MCC Level 2, 1126-1131), ED14A (MCC 3007)

ED: Research Experiences for Under-graduates (REU) at 25: Its impact on un-dergraduate education in the sciencesIn recognition of 25 years of the NationalScience Foundation-Research Experiencesfor Undergraduates (NSF-REU) Program,this session will highlight REU initiatives,examine best practices for research with un-dergraduates in different scientific disci-plines, and assess the role of REU inBachelor’s degree programs today. ED31A(MCC Level 2, 1195-1203), ED41A (MCC3009)

ED: Undergraduate research in the earthand environmental sciences: shaping thecutting edge of our disciplineThis session will explore the role of under-graduate research in establishing the future

direction of the Earth and EnvironmentalSciences. Contributors will showcase ex-amples of the diverse research projects inwhich undergraduate students are involved.ED31B (MCC Level 2, 1204-1214), ED41B(MCC 3009)

G: Aseismic deformation transients andtheir relationship to earthquakesTransient deformation is often detected aftermoderate or large earthquakes nearby, andincludes triggered slip on other faults,afterslip on or near the co-seismic rupture,and viscous and poroelastic deformation inthe lower or upper lithosphere, or it can beassociated with other static or dynamic stresschanges. Much of this deformation isaseismic or seismically small, but non-seis-mic measurements and modeling of causesand effects can provide information on thematerial properties of fault zones and adja-cent lithosphere. G43A, G44A (MCC 3005),G51B (MCC Level 2, 0811-0836)

H: Beyond steady state: The dynamics oftransient landscapesThe last decade has witnessed significantprogress in understanding the linkages amongclimate, surface processes, and tectonics.Contributions to this session pertain to thetransient evolution of landscapes at all scales,from hillslope to orogen, and how transientconditions influence interpretation of data.H31A (MCC Level 2, 1261-1288), H33F,H34A (MCC 3000)

H: Impacts of hydrology on landscape evo-lutionHydrologic processes play important roles inmany aspects of long-term landscape evolu-tion, but also depend on the landscape mor-phology, introducing a feedback mechanismin the system. This session explores linksbetween climatology, basin hydrology, andlong-term landscape evolution via theoreti-cal, observational, and experimental contri-


butions. H42B (MCC 3002), H43D (MCCLevel 1, 0516-0530)

H: Constructional landscapes: From del-tas to leveed channelsChannels that build their own banks are thedominant conduits for water and sedimenttransport in many subaerial and subaqueouslandscapes from lakes to the deep-marinecontinental slope. This session shares ad-vances in understanding the initiation andgrowth of leveed channels and deltas, as wellas the landforms they construct, based onfield, laboratory or numerical studies acrossmultiple disciplines. H44D (MCC 3011),H51D (MCC Level 1, 0393-0404)

H: Coupling sediment transport and chan-nel morphologyMuch remains to be learned about how flowand sediment transport interact to produce themorphology of natural channels. Contribu-tions relate sediment transport to the streammorphology across a range of scales, includ-ing studies linking field or laboratory basedmeasurements of sediment transport to chan-nel adjustment processes. H51H, H52A(MCC 3000), H53B (MCC Level 1, 0455-0476)

H: The hydrogeomorphic interface: Tem-poral and spatial scales of interaction be-tween hydrology and geomorphologyHydrology, geomorphology and aspects ofriverine ecology strongly interact within thecontext of a stream channel network. High-lights of this session include: 1) interactionbetween a changing hydrologic regime, sedi-ment supply and/or stability of channel mor-phology; 2) interaction between stream flowregulation, riparian vegetation and channeldynamics; and 3) temporal and spatial varia-tion of channel forming flows in drainagenetworks. H41I (MCC 3003), H43C (MCCLevel 1, 0506-0515)

H: Quantitative studies of the sources, fate,and transport of dissolved and suspendedmaterials in streamsRivers and streams are conduits for naturallyderived solutes and anthropogenically-pro-duced contaminants in dissolved and particu-late forms. Topics include: 1) weathering,erosion and denudation, and riverine trans-port of particulate and dissolved materials;2) quantitatively identifying or budgetingsediment sources; 3) novel statistical meth-ods to estimate contaminant loads from in-

termittent concentrations data and continu-ous stream flow data. H42B (MCC 3000),H31D (MCC Level 2, 1325-1341)

IN: Building a global geosciencecyberinfrastructure: International col-laboration in geoinformaticsThe emerging cyberinfrastructure for geo-science must be an international effort in or-der to successfully promote advances in geo-science research and enable new approachesto addressing scientific problems that in turnlead to new discoveries and an improvedunderstanding of the Earth. This sessions fo-cuses on collaboration and integration of in-ternational digital data, information, analy-sis and visualization tools. IN43C, IN44A(MCC 3018), IN51A (MCC Level 1, 0305-0316)

S: Fault-zone properties and earthquakerupture dynamicsRecent studies show that fault zone materi-als, fault structures, and stresses applied tothe fault significantly affect earthquake rup-ture dynamics and near-fault ground motions.Contributions include integration of seismicreflection profiles, drilling of active faultzones, in-situ measurements in boreholes, andstructural and microstructural studies thatdefine the prevailing deformation processesaffecting the faulting process. S31B, S32B,S33C, S34A (MCC 3020), S41B, S43A(MCC Level 2, 0977-1002, 1039-1068)

T: Subduction-zone paleoseismology onthe Pacific RimA forum on long records of great earthquakesat Pacific Rim subduction zones, includingearthquake sizes and recurrence intervals,comparisons with the ‘04 and ‘05 Sumatranearthquakes, and applications to seismology,geodesy, engineering, and tsunami simula-tion. T11A (MCC Level 1, 0346-0362)

T: Static and dynamic strengths of faults:Merging field, laboratory and numericalapproachesThe nature of slip on active faults is stronglycontrolled by shear resistance which dependson factors such as accumulated slip, rough-ness, presence of fluids, temperature, pres-sure and transport properties. This sessionexamines relationships between specificmicromechanical processes as observed in thelaboratory, field and imaged inmicromechanical models, and their macro-scopic mechanical response. T13E, T14B

(MCC 3011), T21B (MCC Level 1, 0460-0487)

T: Dynamics, structure, and compositionof subduction zonesUnderstanding the interplay between dynam-ics, structure and composition is crucial todeveloping a comprehensive model of theshallow portions of the subduction zone sys-tem. This session focuses on research intothe critical parameters affecting subductionzone creation, evolution and behavior, includ-ing observations and modeling in novelmultidisciplinary studies. T31D (MCC3011), T33B, T33C (MCC Level 1, 0528-0582), T41F, T42A (MCC 3011)

T: Comprehensive testable predictions ofgeodynamic modelsRecent advanced geodynamic models oper-ate with large number of parameters whoseadjustment may allow fitting of geologicaland geophysical constraints, but do not nec-essarily prove their validity. The aim of thissession is to attract attention of thegeodynamic modelers to the importance ofverification and testing of their models andto involve geologists and geophysicists indiscussion of how to accomplish this. T12A,T13F, T14A (MCC 3024), T21C (MCCLevel 1, 0488-0521)

T: Extensional tectonics and metamorphiccore complexes: Their metamorphic, pet-rographic, and kinematic evolutionWithin the last quarter century, our under-standing of continental extensional tectonicsand associated metamorphic core complexeshas improved substantially, but there are stillmany important questions and debates. As acatalyst for new research, this session bringstogether researchers working on these prob-lems in the well studied extensional terranesof the Basins and Ranges of western NorthAmerica and the Aegean region of southeast-ern Europe. T13C (MCC Level 1, 0482-0493), T24C (MCC 3022)

T: Mechanisms of continental extensionduring basin and rifted-margin formationThe mechanisms by which continentalcrust thins from >30 km to <6 km prior tobreak-up are not well understood, and thereis no consensus on the rheological behav-ior of the lower crust during extension. Thissession considers observational data andnumerical models that give insights intoprocesses such as fault array evolution and


strain localization, strain partitioning withdepth, evolving rift (a)symmetry, and con-jugate margin subsidence patterns. T43B(MCC Level 2, 1389-1415), T51E, T52B,T53E (MCC 3011)

V: Will the real phenocryst please standup?Fractional crystallization is the dominantprocess promoting magma differentiation,but many erupted magmas contain solidphases that are complexly zoned and/or de-monstrably out of equilibrium with theirhost melts. This session addresses the im-portant challenge of converting the infor-mation carried by magma’s ‘crystal cargo’into process-related and component-spe-cific constraints on magma evolution.V11A, V12A (MCC 3007), V13B (MCCLevel 1, 0523-0557)

V: The agent of mass transfer in subduc-tion zones: Fluid, melt, or supercritical?Thermal and chemical exchange betweensubducting oceanic lithosphere and theoverlying mantle wedge at convergentmargins produces what is arguably the mostphysically and compositionally complexmelting regime in the upper mantle. Thissession brings together evidence bearing onthe physical and chemical nature of the sub-duction component and the mass transferprocess in subduction zones. V31C (MCCLevel 1, 0618-0641), V33C, V34A (MCC3009)

V: From the mantle to the surface andback again: Deep storage, degassing, andsubduction of terrestrial volatilesThis session examines terrestrial volatilesin the Earth’s interior, including their char-acteristics in different mantle phases/res-ervoirs, their role during melting, and theircycling to/from the exosphere.Multidisciplinary contributions encompassall aspects of deep Earth volatile cycles.V41A (MCC Level 2, 1416-1437), V51F,V52A, V53F (MCC 3009)

V: Development and evolution ofintraoceanic arc crust: The record fromcrustal sections and xenolithsThe goal of this session is to bring togetherstudies of well-exposed arc crustal sectionsto gain a better understanding of the growthand evolution of intraoceanic arcs and thedevelopment of continental crust. The ses-

sion also includes abstracts on continentalarc lower crust and xenolith studies frommodern arc settings. V44C (MCC 3007),V51D (MCC Level 2, 1513-1526)

V: Temperature, chemistry, and dynam-ics of the mantleTo provide stronger constraints on mantleconvection, volcanism, and plate tectonics,an improved understanding of the major el-ement, trace element, isotopic, and thermalstructure of the mantle is required. This in-terdisciplinary session will address all as-pects of the variations of temperature andchemistry of the mantle and their implica-tions for mantle dynamics and the conten-tious debate on mantle plumes. V31F,V32B, V33D (MCC 3007), V41C (MCCLevel 2, 1453-1473), V41E (MCC Level2, 1503-1522), V43E (MCC 3007)

Other sessions of interest

G: Plate Boundary Observatory andCrustal Deformation. G21B (MCC Level2, 1263-1284)

GP: New insights into Earth’s propertiesand processes from electrical conductivitystudies. GP34A (MCC 3008), GP41B(MCC Level 2, 0867-0882)

H: Exploring the response of high-latitudelandscapes and processes to global change.H51G (MCC Level 1, 0440-0450), H53I(MCC 2002)

IN: Emerging better, or best, practices forDistributed Data Systems and Virtual Ob-servatories. IN23C, IN24A (Marriott Sa-lon 10), IN31B (MCC Level 2, 1143-1159)IN: Data fusion. IN31A (MCC Level 2,1137-1142)

OS: Sedimentation, overpressure, andslope stability along deepwater continen-tal margins. OS21A (MCC Level 2, 1505-1522), OS24A (MCC 2010)

S: Earthquake hazards forecasting: Real-ity, potential, and applications. S42B,S43D, S44B (MCC 3020), S51D, S53B(MCC Level 2, 1027-1048, 1092-1110)

S: The earthquake source. S11C, S12A(MCC 3022), S13B (MCC Level 1, 0188-0209)

S: Earthquakes, active sources and tecton-ics. S21C, S22A (Marriott Salon 3), S23B(MCC Level 1, 0232-0263)

S: Fault-zone properties and earthquakerupture dynamics. S31B, S32B, S33C,S34A (MCC 3020), S41B, S43A (MCCLevel 2, 0977-1002, 1039-1068)

T: Links between ophiolites and the lostlarge igneous provinces record. T11C(MCC Level 1, 039-0403), T21E(Marriott Salon 5)

T: Crustal construction, tectonic, alteration,microbiological, and transport processes onthe flanks of mid-ocean ridges. T23F(MCC 3022), T33A, T33D (MCC Level1, 0509-0527, 0583-0597)

T: Geothermal systems: Fantastic naturallaboratories and a valuable energy resource.T22A (Marriott Salon 5), T23B (MCCLevel 1, 0538-0562)

T: Continental margins: Geodynamic con-straints and implications for the legal con-tinental shelf under UNCLOS. T21C(Marriott Salon 5), T13D (MCC Level1, 0494-0510)

U: Interdisciplinary studies of the 26 De-cember 2004 Great Sumatra-AndamanEarthquake and Tsunami. U11A, U11B(MCC Level 2, 0801-0842), U13A, U14A,U21C, U22A (Marriott Salon 7)

U: Frontiers of geophysics lecture: The2004 Sumatra mega earthquake: Lessonsfrom a monster. U22B (13:00, MarriottSalon 9)

U: Beyond plate tectonics. U43B (MCCLevel 2, 0828-0837), U51B, U52A, U53A(MCC 3001)

V: Massive collapse of volcanoes in islandarcs and continental volcanic arcs: Struc-ture, mechanics, and implications of insta-bility. V13F (Marriott Salon 10), V21B(MCC Level 1, 0598-0607)

V: Seamount hydrothermal systems: Vol-canology, biology, geochemistry andoceanography. V44A (MCC 3009), V51C(MCC Level 2, 1489-1512)

AGU 2005


Time: 6 - 8 pm

Date: Tuesday, 6 December, 2005

Location: San Francisco Marriott, across from the Moscone Center

Room: Golden Gate B2

MARGINS will be hosting a “Lecture and Reception” at this year’s AGU Fall Meeting. This event includes twoinvited lectures from esteemed scientists conducting MARGINS research. Their presentations will be targeted at abroad scientific audience, and will highlight recent advances in the MARGINS Subduction Factory and Source-to-Sink Initiatives.

Prof. Charles Nittrouer is a Professor of Earth and Space Sciences and Coordinator of Strata FORmation on Mar-gins (STRATAFORM). His MARGINS research focuses on sediment transport and accumulation in relation toclinoform development at continental margins. He is extremely active in the Source to Sink community, havingcoordinated one of the Science Plan workshops and served on the MARGINS Steering Committee.

Prof. Douglas Wiens is a Professor in the Department of Earth and Planetary Sciences at Washington University inSt. Louis. Amongst his many roles in scientific research and planning, he is a member of National Academy Inter-national Polar Year Planning Committee, and has served on several committees for Incorporated Research Institu-tions in Seismology (IRIS) and on the Steering Committees for RIDGE2000 and MARGINS.

Both speakers have extensive field and cruise experience as chief scientists and as scientific party members.

margins.wustl.edu agu.org

MARGINS Lecture and Reception

AGU Fall Meeting 2005

The lectures will be followed by updates on MARGINS funding and other issues from NSF Program Officer BilalHaq, and MARGINS Chair Julie Morris.

Washington University in St. Louis, current host of the MARGINS Office and Chair, is co-sponsoring the Recep-tion, which will include ample time for mingling, questions and discussion. Refreshments and light food will beprovided.

Lectures:

The Ties that Bind Source to Sink, within and between New Guinea and New ZealandDr. Charles A. Nittrouer, University of Washington, School of Oceanography.

Geophysical Imaging of the Mantle Wedge: Temperature, Melt, Fluids, and Mantle FlowDr. Douglas A. Wiens, Washington University in St. Louis, Department of Earth and

Planetary Sciences.


ADVERTISEMENT

The Seismogenic Zone of Subduction Thrust FaultsMARGINS Theoretical and Experimental Earth Science Series, Volume 2Columbia University Press, 2006.

Table of Contents

• Timothy H. Dixon and J. Casey Moore, The SeismogenicZone of Subduction Thrust Faults: Introduction

• Roy D. Hyndman, The Seismogenic Zone of SubductionThrust Faults: What We Know and What We Don’t Know

The Incoming Plate

• Michael B. Underwood, Sediment Inputs to SubductionZones: Why Lithostratigraphy and Clay Mineralogy Matter

• M. Hutnak, A. T. Fisher, C. A. Stein R. Harris, K. Wang, E.Silver, G. Spinelli M. Pfender, H. Villinger, R. Macknight, P.Costa Pisani, H. DeShon, and C. Diamente, The ThermalState of 18-24 Ma Upper Lithosphere Subducting Below theNicoya Peninsula, Northern Costa Rica Margin

• Susan L. Bilek, Influence of Subducting Topography onEarthquake Rupture

Convergent Margin Structure, Fluids and

Subduction Thrust Evolution

• Barbara A. Bekins and Elizabeth J. Screaton, Pore Pressureand Fluid Flow in the Northern Barbados AccretionaryComplex: a Synthesis

• Demian Saffer, Pore Pressure Within Underthrust Sedimentsin Subduction Zones

• Julia K. Morgan, Elizabeth B. Sunderland, and Maria V. S.Ask, Deformation and Diagenesis at the Nankai SubductionZone: Implications for Sediment Mechanics, DecollementInitiation and Propagation

• Kirk D. Mcintosh, Eli A. Silver, Imtiaz Ahmed, ArnimBerhorst, Cesar R. Ranero, Robyn K. Kelly, and Ernst R.Flueh, The Nicaragua Convergent Margin: Seismic Reflec-tion Imaging of the Source of a Tsunami Earthquake

• J. Casey Moore, Christie Rowe, and Francesca Meneghini,How Accretionary Prisms Elucidate Seismogenesis inSubduction Zones

Laboratory Studies

• Chris Marone and Demian Saffer, Fault Friction and theUpper Transition From Seismic to Aseismic Faulting

• N.M. Beeler, Laboratory-observed Faulting in Intrinsicallyand Apparently Weak Materials: Strength, Seismic Coupling,Dilatancy and Pore Fluid Pressure

• Diane E. Moore and David A. Lockner, Friction of theSmectite Clay Montmorillonite: a Review and Interpretationof Data

Seismic and Geodetic Studies

• Akira Hasegawa, Naoki Uchida, Toshihiro Igarashi, ToruMatsuzawa, Tomomi Okada, Satoshi Miura, and Yoko Suwa,Asperities and Quasi-static Slip on the Subducting PlateBoundary East off Tohoko, Northeast Japan

• Thorne Lay and Susan Bilek, Anomalous EarthquakeRuptures at Shallow Depths on Subduction ZoneMegathrusts

• Kosuke Heki, Secular, Transient and Seasonal CrustalMovements in Japan From a Dense GPS Array: Implicationfor Plate Dynamics in Convergent Boundaries

• Kelin Wang, Elastic and Viscoelastic Models of CrustalDeformation in Subduction Earthquake Cycles

• Susan Y. Schwartz and Heather R. DeShon, Distinct Up-dipLimits to Geodetic Locking and Microseismicity at theNorthern Costa Rica Seismogenic Zone: Evidence for TwoMechanical Transitions.

Regional Scale Deformation

• Tetsuzo Seno, Collision Versus Subduction: the Importanceof Slab Dehydration

• Jonas Kley and Tim Vietor, Subduction and MountainBuilding in the Central Andes.

• Inside the Subduction Factorywww.agu.org/cgi-bin/agubookstore?book=SEGM1389973&search=subduction%20factory

• Rheology and Deformation of the Lithosphere at Continental Margins www.columbia.edu/cu/cup/catalog/data/023112/0231127383.HTM

Additional MARGINS Volumes Currently AvailableOrder through the web addresses given, or additional information may be found at www.margins.wustl.edu/Books.html


“SF” cont. from Page 5

structures, large-offset crustal imaging ofthe entire arc and backarc crust, and pas-sive (earthquake) imaging of the mantlebeneath arc and backarc. Data collectionwas completed by mid-2004 when OceanBottom Seismometers were recovered;active-source data were collected over thethree prior years. Initial findings havebeen presented at a workshop in Japanin June, 2005, attended by all project sci-entists. Initial results from the earthquakeexperiment have shown significantanisotropy beneath the arc and the pres-ence of a double seismic zone. They alsoshow that thrust zone earthquakes areabsent in the vicinity of forearcserpentinite mud volcanoes, thought tobe the surface expression of extensivehydration of the shallow lithosphericmantle of the upper plate. In December2005, a magnetotelluric experiment willbe deployed along the same transect,which should facilitate tests of hypoth-eses regarding fluid pathways in the slaband wedge. Many of the results will bepresented at a special session on the Izu-Bonin-Mariana subduction factory at the2005 Fall AGU meeting and at the MAR-GINS lecture and reception (see pp. 14and 17, respectively).

The Central America geophysicalprojects benefit from a synergy betweenSEIZE and SubFac, particularly in thecharacterization of the incoming plate(see article, p. 1). The Cocos plate ap-pears unusual in having quite low heatflow associated with vigorous hydrother-mal circulation (Fisher et al., 2003) anddeep bending-related faults that mayserve as significant conduits of fluids intothe subducting mantle (Ranero et al.,2003). Results from ODP Leg 205 andIODP Expedition 301T are showing vig-orous fluid flow in the shallow igneoussection of the incoming plate. Work con-tinues to characterize the incoming plateand in particular to test the hypothesis ofmassive serpentinization of its mantle.The German GEOMAR group has plansfor a series of marine seismic experi-ments in 2005-2006, and a large activesource US-led experiment will take place

when the new multi-channel ship be-comes available.

Along the volcanic arc there are first-order changes in lava chemistry betweenCosta Rica and Nicaragua (Carr, 2003)despite relatively weak differences in theincoming plate (Peacock et al., 2005).Hence, there should be significant differ-ences in how the slab or mantle wedgeprocesses material bound for the arc. Forexample, preliminary analysis of regionalwave propagation indicates that the slabbeneath Nicaragua may be unusuallyhydrated by global standards (Abers etal., 2003). The 48 station TUCAN broad-band experiment, which will be in thefield until March 2006, provides the dataneeded for imaging the downgoing plateand arc mantle (Abers et al., 2004). Thepassive seismic experiment is comple-mented by an active-source crustal im-aging experiment, transecting the arc inCosta Rica and paralleling the TUCANalong-strike transect. The terrestrial partof this experiment was shot during 2 fieldseasons in 2005 (Holbrook, Lizarralde etal., PI’s), and will provide primary dataon the problems of crustal architectureand growth rates. The off-shore compo-nent is awaiting the refitting of the R/VLangseth.

The future of the Subduc-tion Factory Initiative

The maturity of the Subduction Fac-tory Initiative is clearly shown in thenumber of projects that have generatedpublications over the past few years andthe breadth of ongoing research. Manyof the gaps in research identified in thefocus sites by the MARGINS commu-nity and Steering Committee are beingcovered. The 2004 MARGINS ReviewCommittee recognized this maturity andindicated that the SubFac initiative wouldbenefit greatly by having an integrativemeeting. On the other hand, much of thebasic data collection (particularly thegeophysical efforts) are still ongoing, soit may be a bit premature to reach clo-sure on many aspects of the program.Over the next few years, it is expectedthat these studies will reach fruition while

synthesis and programmatic evaluationtakes place.

In order to facilitate such a synthesis,the MARGINS Steering Committee in itsspring meeting this year suggested thatproposals should be solicited for a newintegrative TEI, nominally in 2007 (see“From the MARGINS Chair”, Spring2005 MARGINS Newsletter 14). Al-though focus site work vigorously con-tinues, it is not too early to beginconsidering the future of SubFac. In par-ticular, are there compelling reasons toseek a renewed round of work in thesefocus areas, with goals informed by ear-lier successes, or would change to newfocus sites be something to consider, par-ticularly to sites where cross-programsynergies may be attained (e.g.,Earthscope, IODP, OOI)? At what pointshould basic SubFac science goals be re-evaluated in light of what has beenlearned so far? Answers to these ques-tions will require extensive communityinvolvement and will take some time. Asignificant TEI would be a first step.

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Stern, R.J. (2004) Subduction initiation:spontaneous and induced, Earth andPlanetary Science Letters, Volume 226,275-292.

Thomas, R.B., M.M. Hirschmann, H. Cheng,M.K. Reagan, and R.L. Edwards (2002)(231Pa/235U)-(230Th/238U) of youngmafic volcanic rocks from Nicaragua andCosta Rica and the influence of flux melt-ing on U-series systematics of arc lavas,Geochimica et Cosmochimica Acta, 66,4287-4309.

Wade, J.A., T. Plank, R.J. Stern, D.L.Tollstrup, J.B. Gill, J.C. O’Leary, J.M.Eiler, R.B. Moore, J.D. Woodhead, F.Trusdell et al. (2005) The May 2003 erup-tion of Anatahan volcano, Mariana Is-lands: Geochemical evolution of a silicicisland-arc volcano, Journal of Volcanol-ogy and Geothermal Research, 146, 139-170.

Wiens, D. A., S. H. Pozgay, P. J. Shore, A.W. Sauter, and R. A. White (2005), Tiltrecorded by a portable broadband seis-mograph: The 2003 eruption of AnatahanVolcano, Mariana Islands, GeophysicalResearch Letters, 32, art. no. L18305.

Zimmer, M.M, T. Fischer, D.R. Hilton, G.E.Alvarado, Z.D. Sharp, and J.A. Walker(2004) Nitrogen systematics and gasfluxes of subduction zones; insights fromCosta Rica arc volatiles, Geochemistry,Geophysics, Geosystems, 5, DOI 0.1029/2003GC000651.


“Chair Report” cont. from Page 9

short steep rivers draining the York Pen-insula; tectonic, climatic and ocean cir-culation controls on clinoform construc-tion; the distribution of clastic and car-bonate sediments in the deep part of theGoP; and the fate of terrestrial organiccarbon as it traverses the shallow shelf.A recently funded project focuses atten-tion on the tidally dominated delta of theFly River, from a modeling perspective.Areas needing additional attention in-clude sediment supply from the uplandsas a function of changing climate andtectonics through time, including thestratigraphic record archived in LakeMurray and the sediment dispersal andstorage in the shallow (<20m) shelf. Re-cent work has also highlighted the im-portance of the ENSO record archivedoffshore and the exemplar the region pro-vides as a modern foreland basin. Forboth focus areas, work on land (bothobservational and theoretical) remains animportant need. Integration betweenMARGINS S2S and the CommunitySurface Dynamics Modeling System (seepage 10, this Newsletter) is a high pri-ority.

MARGINS DistinguishedLecturer Series

Response to the MARGINS lectureseries has been exceptional, and with alarge number of requests coming in eachcontaining an enthusiastic endorsementof the scientific impact the speakers willhave on the hosting colleges and univer-sities. For our inaugural year, speakersare Neal Driscoll, Susan Schwartz, JoannStock and Terry Plank. Titles for theirtechnical and public lectures are shownin the box below. Our thanks to all thespeakers for the time and energy they willcontribute, and congratulations on the ex-cellent response they’ve generated. If youwould like to nominate speakers (includ-ing yourself) for consideration for nextyear’s distinguished lecturers, pleasedrop us a line.

MARGINS Education Plan-ning

An ad hoc organizing committee fora future workshop on educational initia-tives to accompany MARGINS researchmet at the MARGINS Office in mid-Oc-tober. The group spent two days brain-storming on a series of efforts that willbe the focus of an education and outreachworkshop to be held in mid-2006. Poten-tial discussions at the workshop may in-clude the development of undergraduateresearch projects and mentorships, exten-sions of the Distinguished Lecture Series

to include the production of DVDs forwidespread distribution to institutions,and multimedia products for classroomuse that take advantage of the MARGINSdatabase, to name but a few.

MARGINS at AGU

If you look to p. 17 you’ll see thatwe’re doing something a little differentthis year at AGU. We’re very pleased thatAGU have allocated after-hours meetingspace for a “MARGINS Lecture and Re-ception,” to be held at 6 pm on Tuesday,December 6th, in the Marriott GoldenGate Room B2. This event will offer twoMARGINS lectures of broad interest,along with Program and funding newsfrom me and from our MARGINS Pro-gram Officer, Dr. Bilal Haq. We are for-tunate to have two widely renowned andengaging speakers for the event, ChuckNittrouer and Doug Wiens have kindlyagreed to deliver lectures (see p. 17 fordetails). If you’re at AGU, please join usfor what we expect to be a top notchevent! During AGU we will also be run-ning the $1000 MARGINS Student Prize,now in its third year. The MARGINSOffice (Paul and Meredith) and I will bein and around the meeting all week, andare always ready to listen to your com-ments or questions. We look forward toseeing you there.

Distinguished Lectureship Series - Technical and Public Lectures(Dates and venues to be determined)

Neal Driscoll (Scripps Institution of Oceanography) - Source to SinkPublic Lecture: Reading Earth history from the geologic recordTechnical Lecture: Dispersal systems in actively deforming regions: Papua New Guinea has it all!

Terry Plank (Boston University) - Subduction FactoryPublic Lecture: Recycling within the Subduction FactoryTechnical Lecture: The effect of water on mantle melting at subduction zones

Susan Schwartz (University of California, Santa Cruz) - Seismogenic ZonePublic Lecture: Great Earthquakes and Tsunamis: Causes and EffectsTechnical Lecture: Seismic, Geodetic& Fluid Flow Constraints on Seismogenic Zone Procsses in Costa Rica

Joann Stock (California Institute of Technology) - Rupturing of Continental LithospherePublic Lecture: Plate tectonics and how continents split apartTechnical Lecture: Defining the continent/ocean boundary: Insights from active rifts

For more information on the MARGINS Distinguished Lectureship Program visitwww.margins.wustl.edu/DLProgram/


scientific oversight from a CSDMSSteering Committee and will report toNSF and other funding agencies involvedin the project. Working groups/nodes willliaise with each other and report to OIand the Steering Committee, as needed.

It is envisioned that after the estab-lishment of the OI and when deemed ap-propriate, individual PI(s) proposals maybe invited for modeling studies of vari-ous components of the system within theoverall CSDMS framework. TheCSDMS Steering Committee will pro-vide planning and guidance concerningthe development of individual modulesthat will populate various components ofthe system and help stimulate proposalsand input from the community. Propos-als from individual PIs for the develop-ment of these modules under the umbrellaof CSDMS may be funded from the coreas well as special programs. Groups in-terested in submitting proposals for thedevelopment of the OI for CSDMS arerecommended to consult the Division ofEarth and Ocean Sciences websites forrules of proposal submittal under the GIand MARGINS initiatives.

“CSDMS” cont. from Page 10

making recommendations for resourceprioritization; scientific review; and tech-nical documentation. Several environ-mental and logistical/technical workinggroups may be established, as needed.The OI will receive advice, guidance and

“Nicaragua” cont. from Page 2

Journal of Volcanology and Geothermal Research Special Issue -

“The 2003 Eruption of Anatahan Volcano, Commonweath of the

Northern Mariana Islands”

sula, Costa Rica from 3D local earthquaketomography using P- and S-wave data,Geophys. J. Int., in press.

Ihmlé, P. M. (1996), Monte Carlo slip inver-sion in the frequency domain: Applica-tion to the 1992 Nicaragua slow earth-quake, Geophys. Res. Lett., 23 913-916.

Kanamori, H., and M. Kikuchi (1993), The1992 Nicaragua earthquake: A slow tsu-nami earthquake associated with sub-ducted sediments, Nature, 361, 714-716.

Kikuchi, M., and H. Kanamori (1991), In-version of complex body waves III, Bul-letin of the Seismological Society ofAmerica, 81, 2335-2350.

A special issue of Journal of Volcanology and Geothermal Research is now available (vol-ume 146, issue 1-3, on-line 15 August 2005) and is dedicated to the first historical eruptionof Anatahan Volcano in the Commonwealth of the Northern Mariana Islands (CNMI) inMay 2003. Thirteen research papers cover (a) geological studies of Anatahan carried outprior to the May, 2003 event, including mapping of both the submarine and subaerial por-tions of the volcano and monitoring of the local seismicity following activity in 1990, (b)geophysical signals of the 2003 eruption, (c) petrology and geochemistry of the eruptiveproducts of the 2003 eruption, and (d) hazard impacts associated with the 2003 eruption.Edited by David Hilton (a MARGINS-funded PI), John Pallister (USGS) and Rudi Pua(EMO), this special issue includes contributions arising from samples and other data col-lected from Anatahan in the course of NSF-MARGINS-funded research.

Anatahan has twice been a MARGINS Event Response site since the May 2003 eruption. Updates on the latestMARGINS event response to the island can be found in MARGINS Newsletter No. 14, Spring 2005.

www.elsevier.com/locate/jvolgeores

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MARGINS Steering Committee

Bilal HaqMarine Geology and Geophysics Program

Division of Ocean SciencesTel: (703) 292-8582Fax: (703) 292-9085

e-mail: [email protected]

Rodey BatizaOcean Drilling Program

Division of Ocean SciencesTel: (703) 292-8581Fax: (703) 292-9085


William LeemanPetrology and GeochemistryDivision of Earth Sciences

Tel: (703) 292-7411Fax: (703) 292-9025


NSF Program DirectorsNational Science Foundation, 4201 Wilson Boulevard, Arlington, Virginia 22230

This information is also posted on the MARGINS website, where it is continuously updated.

Contact Information

Julie Morris, ChairDepartment of Earth and Planetary SciencesWashington University in St. LouisCampus Box 1169One Brookings DriveSaint Louis, MO 63130Tel: (314) 935-6926e-mail: [email protected]

Geoffrey AbersDepartment of Earth SciencesBoston University685 Commonwealth AvenueBoston, MA 02215Tel: (617) 353-2616e-mail: [email protected]

Paul J. UmhoeferDepartment of Geology, Box 4090Northern Arizona UniversityFlagstaff, AZ 86011Tel: (928) 523-6464e-mail: [email protected]

Uri S. ten BrinkU.S. Geological Survey384 Woods Hole Rd.Woods Hole, MA 02543Tel: (508) 457-2396e-mail: [email protected]

Rudy SlingerlandDepartment of GeosciencesPenn State University503 Deike BldgUniversity Park, PA 16802Tel: (814) 865-6892e-mail: [email protected]

John MillimanVirginia Institute of Marine ScienceCollege of William and MaryP.O. Box 1346Cloucester Point, VA 23062Tel: (804) 684-7105e-mail: [email protected]

Lincoln PratsonDivision of Earth and Ocean SciencesDuke University203 Old Chem Bldg, Box 90230Durham, NC 27708-0277Tel: (919) 681-8077e-mail: [email protected]

Don ReedDepartment of GeologySan Jose State UniversitySan Jose, CA 95192-0102Tel: (408)924-5036e-mail: [email protected]

Liz ScreatonDepartment of Geological SciencesUniversity of Florida241 Williamson, Box 112120Gainesville, FL 326111Tel: (352) 392-4612e-mail: [email protected]

Peter van KekenDepartment of Geological Sciences425 East University AvenueUniversity of MichiganAnn Arbor, MI 48109-1063Tel: (734) 764-1497e-mail: [email protected]

Julia K. MorganDepartment of Earth Science, MS-1266100 Main StreetRice UniversityHouston, TX 77005-1892Tel: (713) 348-6330Houston, TX 77005-1892email: [email protected]

W. Roger BuckLamont-Doherty Earth ObservatoryRt. 9WPalisades, NY 10964Tel: (845) 365-8592e-mail: [email protected]

Mike BlumDepartment of Geology and GeophysicsE235 Howe-Russell Geosciences ComplexLouisiana State UniversityBaton Rouge, LA 70803Tel: (225) 578-5735e-mail: [email protected]

Mark ReaganDepartment of GeoscienceUniversity of IowaIowa City, IA 52242Tel: (319) 335-1802e-mail: [email protected]

Jeff RyanDepartment of GeologyUniversity of South Florida4202 East Fowler Ave., SCA 528Tampa, FL 33620-5201Tel: (813) 974-1598/6287e-mail: [email protected]

MARGINS OfficeWashington University in St. Louis, Department of Earth and Planetary Sciences

1 Brookings Drive, CB 1169, St. Louis, MO 63130Tel: (314) 935-9367, Fax: (314) 935-7361, E-mail: [email protected],Website: www.margins.wustl.edu

This newsletter is supported by the National Science Foundation underGrant No. OCE 03-25002. Any opinions, findings, and conclusionsexpressed in it are those of the authors and do not necessarily reflect theviews of the National Science Foundation.

Upcoming Meetings:

AGU Fall Meeting 2005San Francisco, California, December 5-9, 2005

www.agu.org/meetings/fm05/

2006 Ocean Sciences MeetingHonolulu, Hawaii, February 20-24, 2006

www.agu.org/meetings/os06/

AAPG 2006 Annual ConventionHouston, Texas, April 9-12, 2006

aapg.org/houston/index.cfm

The 2006 AGU Joint AssemblyBaltimore, Maryland, May 23–26, 2006

www.agu.org/meetings/ja06/

More information about MARGINS-related meetings is posted on the Meet-ings page at the MARGINS web site:

www.margins.wustl.edu/Meetings.html

MARGINS OfficeWashington University in St. Louis

1 Brookings Drive, CB 1169

St. Louis, MO 63130 USA

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This newsletter is produced on behalf of MARGINS by the MARGINS Office:Editors: J. Morris <[email protected]> and P. Wyer <[email protected]>Composition, graphics, and sub-editing: M. Berwick <[email protected]>