development of a regional stratigraphic framework for upper … · 2019. 7. 17. · with sequence...

Perth, WA, 18–21 August 2013 West Australian Basins Symposium 2013 1

1 Chevron Energy T echnology Company, 1500 Louisiana St., Houston, Texas, 77002, USA; [email protected]

2 Geological Survey of Western Australia, Department of Industry and Resources, 100 Plain St., East Perth, Western Australia, 6004, Australia

3 Chevron Upstream Europe, Seafield House, Aberdeen, Scotland, AB15 6XL, United Kingdom

4 University of W estern Australia, School of Earth and Geographical Sciences M004, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia

5 University of W ashington, Department of Biology , Seattle, Washington, 98195, USA

6 Chevron Energy T echnology Company , 6001 Bollinger Canyon Rd., San Ramon, California, 94583, USA

7 Curtin University, Department of Chemistry, Perth, Western Australia, 6845, Australia

8 Institute for T ibetan Plateau Research, 18 Shuangqing Rd., Haidian, Beijing, China, 100085

9 California Institute of T echnology, Division of Geological and Planetary Sciences, 1200 East California Blvd., Pasadena, California, 91125, USA

10 University of St. Andrews, Department of Earth Sciences, St. Andrews, Scotland, KY16 9AL, United Kingdom

11 Chemostrat Ltd., Unit 1, Ravenscroft Court, Buttington Cross Enterprise Park, Welshpool, Powys, England, SY21 8SL, United Kingdom

12 University of Greenwich, School of Science, Chatham Maritime, Kent, England, ME4 4TB, United Kingdom

Abstract

Questions regarding heterogeneity and architecture of reefal carbonate platform systems may be resolved by well-constrained chronostratigraphic frameworks, developed from the integration of multiple independent signals in the rock record. This makes possible a meaningful

comparison of coeval stratigraphy and facies in different settings. For the Canning Basin Chronostratigraphy Project (CBCP), key outcrop transects and shallow cores were logged for lithofacies and sampled at sub-meter scale for magnetostratigraphy, stable isotope chemostratigraphy, conodont-fish biostratigraphy, biomarker geochemistry, and elemental chemostratigraphy. The dataset entails nearly 4 km of measured stratigraphy and 6800 samples of Middle and Upper Devonian (Givetian, Frasnian and Famennian) carbonate platform-top, reef, foreslope, and basinal deposits along the Lennard Shelf, Canning Basin, Western Australia. The extracted rock signals were integrated in conjunction with sequence stratigraphic concepts to generate a multi-facetted, regional chronostratigraphy and predictive lithofacies model across 250 km of the exposed Devonian reef complexes.

Final results from the ongoing project will include:

• high-resolution, high-confidence correlations across different carbonate settings that were not achievable before using traditional biostratigraphy or sequence stratigraphic concepts;

• unprecedented examination of Lennard Shelf carbonate heterogeneity and architecture within the constrained framework;

• an integrated workflow for establishing robust chronostratigraphic frameworks that can be tailored for the subsurface;

• a magnetostratigraphic framework for parts of the Late Devonian (a period of uncertainty in the polarity reversal record), calibrated to biostratigraphic zones; and

Development of a Regional Stratigraphic Framework For Upper Devonian Reef Complexes Using Integrated Chronostratigraphy: Lennard

Shelf, Canning Basin, Western Australia

T.E. Playton1, R. Hocking2, P. Montgomery3, E. Tohver4, K. Hillbun5, D. Katz6, P. Haines2, K. Trinajstic7, M. Yan8, J. Hansma4, S. Pisarevsky4,

J. Kirschvink9, P. Cawood10, K. Grice7, S. Tulipani7, K. Ratcliffe11, D. Wray12, S. Caulfield-Kerney12, P. Ward5 & P. Playford2

Keywords: Lennard Shelf, chronostratigraphy, Devonian, carbonate, reefs

THIS PAPER PRESEnTS THE SUMMARY o F A PLEnARY PRESEnTATIon on LYAnD IS no T A PEER-REvIEWED TECHnICAL PAPER

2 West Australian Basins Symposium 2013 Perth, WA, 18–21 August 2013

T.E. PLAYTon ET AL.

Scope, Dataset, and Collaboration

The aim of the CBCP is to develop and demonstrate the workflow and proof of concept of an integrated chronostratigraphic approach via the world-class, well-preserved Middle to Upper Devonian (Givetian, Frasnian, and Famennian) carbonate outcrops of the Lennard Shelf, northeastern Canning Basin, Western Australia (Fig. 1). This outcrop belt was chosen due to 1) minimal structural and diagenetic overprinting since deposition, 2) well-exposed platform-top, reef, slope, and basinal depositional settings, and 3) a well-established pre-existing groundwork to leverage from. This foundation of previous work consists of more than five decades of research (see Playford et al., 2009 for comprehensive compilation) that provided a framework for basin development, structural setting, evolution of the reefal carbonate platforms, facies models, and numerous other characteristics of the depositional system. Another key leveraging point for the CBCP is a robust biostratigraphic framework from conodonts (e.g. Klapper, 2007) and cephalopods (e.g. Becker & House, 1997), among others. Examples of some key works on the margins and slopes of the Lennard Shelf include Playford (1984), Kerans (1985), George et al. (1997), and Playton (2008), however are still limited in terms of slope sequence stratigraphy and margin to slope anatomy due to the inability to correlate across localities or from coeval platform-top successions.

The scope of the CBCP is to collect data 1) over the 30+ Ma (Gradstein and Ogg, 2004) of reefal platform development from the Givetian to Famennian to generate a regional chronostratigraphic framework for the system, 2) in platform-top, reef, slope, and basinal environments for correlation of depositional profiles, and 3) across different paleogeographic settings to demonstrate regional correlation capability. Thus, key outcrop transects with an appropriate degree of overlap were chosen to fulfill these coverage requirements, and shallowWinkie cores or subsurface mineral cores were incorporated to infill gaps in outcrop measured section availability (Figs. 1, 2, and 3). In addition to detailed logging for rock identification and sedimentology, outcrop sections or cores were sampled or measured for magnetostratigraphy (polarity reversals and magnetic susceptibility), stable isotope chemostratigraphy (inorganic carbon and oxygen), elemental chemostratigraphy, conodont-fish biostratigraphy, biomarker geochemistry, and natural gamma ray (Figs 4 & 5). Samples collected include oriented outcrop plugs and hand samples (required for paleomagnetics), unoriented hand samples, and large slabs that were tied to stratigraphic logs. Shallow Winkie coring provided up to 40 m of oriented stratigraphic coverage from the surface, while subsurface mineral cores made available up to 700 m of stratigraphy, however unoriented. Five field seasons and over 125 person-weeks of fieldwork were required to complete data collection, totaling nearly 6800 samples and 4 km of measured stratigraphy (Table 1). A vigilant and detailed field safety protocol was established and executed to

• geochemical and elemental profiles that reflect sea level fluctuations, water column stratification/circulation, and biotic crises during deposition of the reef complexes.

The integrated framework and predictive depositional model for the Devonian reef complexes will be a comprehensive product that serves as an analogue for carbonate researchers and petroleum geoscientists worldwide.

Introduction

Carbonate depositional systems are notoriously difficult to predict, characterize, and correlate, especially reefal carbonate platforms that entail 1) complex shelf-reef-slope transitions and 2) slope to basin settings with diverse deposit types and considerable lateral variability. Playton et al. (2010) provided a classification of end-member carbonate slope deposits, margin styles, spatial heterogeneity types, and conceptual margin-slope-basin models that provided a framework for characterizing these systems. However, gaps still remain, including: 1) correlation of platform-top to slope settings through heterogeneous reefal environments, 2) the manifestation of sequences recognizable through platform-top stacking patterns in slope environments, and 3) the differential development of slopes as a function of paleogeography and long-term accommodation change, among many others. The applied need for these improved characterization and prediction capabilities is omnipresent, with significant carbonate reservoirs or plays such as 1) Tengiz and Karachaganak Fields, Kazakhstan (e.g. Collins et al., 2006: Katz et al., 2010) that involve margin-upper slope productive facies, 2) Poza Rica Field, Mexico and numerous examples in the Midland Basin, west Texas (e.g. Montgomery, 1996; Janson et al., 2011) that are conventional basin floor reservoirs, and 3) the ‘Wolfberry’ play in the Midland Basin, west Texas (e.g. Ejofodomi et al., 2010) which is an unconventional lower slope to basin reservoir trend.

Typical subsurface datasets do not provide the constraints necessary to correlate and characterize carbonate margin-slope-basin reservoir facies with certainty or at an adequate scale, as seismic data and biostratigraphic control are seldom at a desirable resolution, and rock data available through core has predictive limitations because sequence stratigraphic rules and stacking patterns are not yet developed for reef, slope, and basinal settings. Other data that exist in the rock record, including paleomagnetic, isotopic, and elemental signals, can be extracted from core and cuttings and incorporated with historical subsurface data to increase the number of constraints and reduce the number of decisions during correlation. This notion defines the premise and vision of the Canning Basin Chronostratigraphy Project (CBCP), where high-confident, high-resolution chronostratigraphic frameworks are generated through integration of multiple independent data types.


LEnn ARD SHELF DEvon IAn CHRono STRATIGRAPHY

and support roles. Table 2 summarizes this integrated partnership which involves a number of 1) Australian, American, and British universities, 2) Australian government entities, 3) Australian, American, and British organizations within the petroleum industry, and 4) Australian and British private vendors. Groups with specialized technical disciplines

result in zero safety incidents during the five-year fieldwork effort.

Considering the breadth of the CBCP in terms of discipline and expertise, a cross-functional collaboration was required across academia, government, industry, and private enterprises, ranging from technical, logistical, administrative,

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after Playford et al., 2009, and Frost & Kerans, 2010). Red labels indicate data collection localities of the CBCP.

WNA-B = Windjana North A-B measured sections. WS = Windjana Slope measured section. WV = Windjana V alley measured section. SO = South Oscars measured section. PRQ = Pillara Road Quarry measured section. VHS = Horse Spring measured section. HD14 = Horse Spring mineral core. UD2 = Horseshoe Range mineral core. NHW = Henwood W est measured section. PGH = Guppy Hills measured section. WK1 = W ade Knoll Winkie core. CL = Casey Falls measured section. MR1 = McWhae Ridge Winkie core.


T.E. PLAYTon ET AL.

progress, and although final interpretations will undoubtedly change upon introduction of additional constraints, we here present the collaborative approach, dataset, and proof of concept of integrated chronostratigraphy that is the purpose of the CBCP.

Integrated Chronostratigraphy of the Lennard Shelf

The integrated chronostratigraphic approach entails utilizing multiple independent signals embedded in the rock record in conjunction with sequence stratigraphic concepts to interpret and correlate time-significant surfaces within a dataset while honoring as many constraints as possible. The end product is a predictive sequence stratigraphic framework that abides by all constraints, but is ultimately tied to and interpreted based on the sedimentology of the rocks. The real

and particular roles (i.e. paleomagnetics) each developed their own protocols for sample processing, quality control, and data validation (details not discussed herein). These substantiation steps, including reproduction of data signals through comparison of parallel sections and robust ties to well-accepted global secular curves, assure unadulterated data signals and verify the robustness of the CBCP sample dataset to demonstrate the integrated chronostratigraphic approach.

Currently, 85–90% of samples collected have been processed and analyzed for paleomagnetics, isotopes, and biostratigraphy, yielding enough data to generate a preliminary regional correlation framework for the Lennard Shelf based from conodont biozone, magnetic polarity, and global to regional stable isotopic constraints. Data from the remaining 10–15% of samples under analysis, and magnetic susceptibility, elemental, outcrop gamma, and biomarker data, have yet to be incorporated. Thus, this manuscript represents a work-in-

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Figure 2. Diagram showing CBCP sampling coverage in terms of age (y-axis), depositional environment (x-axis), and sample transect

type (colors). F/F boundary = Frasnian-Famennian extinction boundary . U, M, and L indicate Upper, Middle, and Lower subdivisions of

Stages, respectively, and are arbitrarily spaced. Single sections or cores can record multiple environments over time, as indicated by

dashed lines.



Figure 3. Examples of outcrop localities sampled for the CBCP. a) Frasnian platform interior cycles of the Windjana North B Section

(WNB). b) Frasnian reef flat cycles of the Windjana North A Section (WNA). c) Middle to upper slope strata of the Windjana Slope

Section (WS). d) Middle slope strata of the South Oscars Section (SO). e) Upper slope strata of the Casey Falls Section (CL). See Fig. 1 for

locations along the Lennard Shelf.

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T.E. PLAYTon ET AL.

Figure 4. Example of CBCP measured section with associated data. Green arrows and labels along depth scale indicate conodont picks

(see Klapper, 2007, for more detail). a) Stratigraphic log for South Oscars (SO) middle slope locality (see Fig. 1 for location). See Fig. 5

for facies color scheme. Textural classes at base of log are as follows: M = mudstone, W = wackestone, P = packstone, G = grainstone,

R = rudstone/fine breccia, Br = megabreccia, B = boundstone. b) Geomagnetic polarity profile. See Fig. 5 for scheme. c) Magnetic

susceptibility profile. Units in SI. d) Stable inorganic carbon isotope profile. Units in ‰ VPDB. (e) Natural gamma ray profile from

handheld outcrop device. Units in CPS. (f) Example of trace element ratio profile (normalized, unitless). Over 50 element concentrations

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Figure 5. Legend applicable to Figures 4, 6, & 7, including schemes for CBCP universal facies (left), sequence stratigraphic interpretations,

geomagnetic polarity reversals, conodont picks, correlation surfaces, and depositional settings for Figure 7 inset.

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T.E. PLAYTon ET AL.

Devonian timescale (see Gradstein & Ogg, 2004). Thus, the CBCP is the first to develop such a magnetic timescale for this time period, and requires additional constraints to do so.

• A global secular stable carbon isotope curve is available for the Middle-Upper Devonian (Buggisch & Joachimski, 2006), and allows for linkage of CBCP data to global δ13C excursions. However, the primary marine isotopic signal, which is required to identify globally-significant excursions for correlation, is compromised in platform-top settings due to meteoric diagenetic overprint and alteration (Hillbun et al., 2012). Thus, only isotope profiles from slope and basin settings can be utilized with confidence.

• Conodont biostratigraphy is very well-established from decades of excellent work (e.g. Klapper, 2007), and allows

differentiator in our proposed approach is not the use of novel data types and techniques, but the integrated incorporation of well-established tools that are not conventionally employed in outcrop studies or subsurface characterization efforts, and furthermore seldom applied in conjunction. As stated, the focus of this manuscript is the use of geomagnetic polarity reversals, stable carbon isotope geochemistry, conodont biostratigraphy, and ultimately sequence stratigraphy to develop a Lennard Shelf correlation framework over great distances that links physically disconnected localities of different depositional facies and oceanographic settings (Figs. 1 & 2). These correlation constraints each have associated strengths and limitations, as the following bullets highlight.

• Geomagnetic polarity reversals have global significance and are environment independent, however a global reference chart is not available for linkage to the Middle to Upper

Section/Core Name

Type Location Age Depositional Environment

Thickness (m)

Samples Collected

Windjana North A (WNA)


north of Windjana Gorge

M-U Fras platform-top/reef flat

143 314

Windjana North B (WNB)



M-U Fras platform-top/reef flat

171.3 368

Windjana Slope (WS)



M Fras- L Fam reef/middle- upper slope

258.5 369

Windjana Valley (WV)



U Fras- U Fam middle-upper slope

510 535

South Oscars (SO)*


southern Oscar Range

M Fras- U Fam middle-upper slope

666.6 905

Horse Spring (VHS)


west of Horseshoe Range

M Fras- M Fam lower-middle slope

102 312

Casey Falls (CL)* outcrop measured section

Mimbi area U Fras- U Fam lower-upper slope 520.2 833

Guppy Hills (PGH)*


south of Horseshoe Range

Giv- L Fras platform-top/reef flat/slope

496.1 797

Henwood West (NHW)


near Horseshoe Range

U Fras- L Fam reef to platform-top

66.6 120

Pillara Quarry (PRQ)

quarry-cut measured section

Pillara Mine Giv reef flat/upper slope

14 89

McWhae Ridge (MR1)

shallow Winkie core

Mimbi area M Fras- L Fam lower slope/Basin 42.2 155

Wade Knoll (WK1)

shallow Winkie core

north of Mimbi area

Giv?- L Fras lower slope/Basin 37.95 73

UD2 subsurface mineral core

Horseshoe Range M Fras- U Fam middle slope to platform-top

703 1358

HD14 (Horse Spring)

subsurface mineral core

west of Horseshoe Range

Giv- L Fras platform-top/reef flat/slope

250.6 546

Table 1. Table of CBCP dataset by section or core, including data type, location (see Fig. 1), age, depositional environment, stratigraphic

thickness, and samples collected. Total thickness of measured stratigraphy and total samples collected also provided.



Tinker, 1997), however is limited in terms of age control and regional stratigraphic context (i.e. unclear which sequence within the sequence set). Conversely, slope and basin stratigraphic data is easily dated due to well-preserved indicator biota and isotope signals, however the determination of sequence stratigraphic surfaces and systems tracts is problematic as rules and stacking patterns lack in these settings. Physical linkage of measured sections to key outcrop localities with regional stratigraphic context and confirmed systems tracts (i.e. margin relationships are observable), such as the ‘Classic

for linkage of stratigraphic sections to Stages, substages, and biozones, and correlation of physically disconnected stratigraphy. However, the resolution and overlap of biozones in some cases is not sufficient for high-resolution sequence stratigraphy. Furthermore, Devonian conodonts are only found in slope to basin settings, thus platform-top or reefal environments lack biostratigraphic control.

• Sedimentologic information in platform-top settings is useful in determining sequences and systems tracts through stacking pattern analysis (sensu Kerans &

Organisation Personnel Role

Chevron Energy Technology Company (San Ramon, CA; Houston, TX)

T. Playton, D. Katz, S. Meyer, J. Hsieh project coordination; sedimentology/stratigraphy; field safety/logistics; field data collection; funding

Chevron Upstream Europe (Aberdeen, UK)

P. Montgomery project strategy/vision; field data collection

University of St. Andrews (St. Andrews, UK)

P. Cawood project strategy/vision; field data collection

Chevron Australia Business Unit (Perth, WA)

W. Robinson, S. O’Connell, U. Singh, G. Beacher, A. Duffy, A. Vonk, M. Thorp

safety/logistical support; funding; field data collection

Geological Survey of Western Australia (Perth, WA)

R. Hocking, P. Haines, R. Addenbrooke, T. Holland, H. Allen, L. McEvoy, P. Playford

project coordination; sedimentology/stratigraphy; field safety/logistics; field data collection; field area access

University of Western Australia (Perth, WA)

E. Tohver, J. Hansma, S. Pisarevsky, L. Lanci, F. Wellmann, F. Pardini, K. Liebe

project coordination; paleomagnetics; grant administration; field data collection

Institute for Tibetan Plateau Research (Beijing, China)

M. Yan paleomagnetics; field data collection

University of Washington (Seattle, WA, USA)

K. Hillbun, P. Ward, T. Tobin, S. Schoepfer

stable isotope geochemistry; field data collection

Curtin University (Perth, WA) K. Trinajstic, K. Grice, S. Tulipani, E. Maslen, K. Williford

biostratigraphy; biomarkers; field data collection

California Institute of Technology (Pasadena, CA)

J. Kirschvink, S. Peek, M. Diamond, T. Raub, S. Slotznick

paleomagnetics; Winkie coring; field data collection

Chemostrat Ltd. (London, UK) K. Ratcliffe, E. Davies, M. Wright, G. Rotberg, J. Sano

elemental chemostratigraphy; field data collectionel

University of Greenwich (Kent, UK) D. Wray, S. Caulfield-Kerney elemental chemostratigraphy

University of Arizona (Tucson, AZ) M. Ducea, D. Dettman radiogenic & stable isotope geochemistry

Wundargoodie Aboriginal Safaris (Wyndham, WA)

Morgan family & crew field outfitting/logistics/safety

Australian Research Council (Linkage Program)

n/an/a funding

Minerals & Energy Research Institute of Western Australia

P. Smith funding

Commonwealth Scientific & Industrial Research Organization

I. Gonzalez-Alvarez support

Buru Energy Ltd. A. Cook support

Table 2. Table of CBCP organizations, participants, specialties, and roles.


T.E. PLAYTon ET AL.

stacking patterns and repeatable stable isotopic trends, many of which were considered regional in extent (not necessarily present on the global secular curve, but present across the Lennard Shelf ). These rules and conceptual models allowed for sequence stratigraphic interpretation of slope and basin successions in portions of the dataset without coeval platform-top equivalents.

The result of these steps is a regional sequence stratigraphic framework across the dataset that is constrained by multiple parameters, which are independent of one another yet in agreement, and calibrated to key areas such as the ‘Classic Face’ (Fig. 7). The framework connects shelf to basin depositional environments and variable paleogeographic settings along strike encompassing more than 250 km of outcrop belt –correlations that were not achievable prior. This result, albeit preliminary, demonstrates the proof of concept of an integrated chronostratigraphic approach with an ancient carbonate outcrop dataset, and makes possible the examination of coeval facies, settings, and stratigraphy at higher resolutions and with greater confidence.

Implications

The resultant integrated framework generated through this multi-faceted chronostratigraphic approach (Fig. 7) allows for unprecedented examination of Lennard Shelf carbonate heterogeneity, depositional architecture, and sequence stratigraphy, and emphasizes the improvement in correlation and characterization that was not previously achievable using only traditional sequence stratigraphic or biostratigraphic techniques. In addition to a workflow for higher-resolution, higher-confidence stratigraphic correlation, and advances in the understanding of Lennard Shelf-specific carbonate development, this study contributes substantially to global references for Middle-Upper Devonian chronostratigraphy and provides conceptual models for carbonate reefal systems that are applicable to academic and applied studies around the globe. Products and concepts as a result of this study include:

• rules and conceptual models for carbonate slope sequence stratigraphy, including facies stacking patterns with respect to position within long-term sequence sets;

• predictive concepts for carbonate margin and slope development relative to paleogeographic setting and basement configuration;

• insights on platform interior stratigraphic architecture and stacking patterns, including limitations;

• a high-resolution Famennian sequence stratigraphic framework for the Lennard Shelf;

• the first-ever global geomagnetic polarity timescale for the Middle-Upper Devonian, to be used as a reference for chronostratigraphy worldwide;

Face’ in Windjana Gorge (Playford, 1980; Playford et al., 2009), can be critical pinning points in the integrated chronostratigraphic workflow as they provide age context for platform-top settings and systems tract calibration for slope to basin settings.

Given these sets of limitations and utilities, an iterative workflow was developed for the generation of an integrated chronostratigraphic, and sequence stratigraphic, framework for the Lennard Shelf (refer to Fig. 6 for this section).

1. A natural starting point for CBCP dataset integration was linking the existing conodont biostratigraphic framework to slope and basin sections, thereby setting up an age-constrained template to interpret paleomagnetic reversals and global isotope excursions within.

2. Another critical first step was physically connecting key platform-top sections to the ‘Classic Face’ in Windjana Gorge, where the transition from Middle Frasnian aggrading sequences to Upper Frasnian prograding sequences can be observed (Playford et al., 2009). This linkage provided coarse age control and stratigraphic context to interpret the placement of stacking pattern-based surfaces and systems tracts of platform-top sections within the regional sequence framework.

3. In biostratigraphically-constrained slope and basin sections, paleomagnetic reversals and mixed polarity intervals were correlated to establish a Middle-Upper Devonian geomagnetic reference, as well as a set of slope/basin correlation constraints across the dataset of higher resolution than those from conodonts.

4. Likewise, in biostratigraphically-constrained slope and basin sections, where the primary marine inorganic carbon isotopic signal is well-preserved, global isotope excursions were identified using the global secular curve (Buggisch & Joachimski, 2006), correlated, and validated through magnetostratigraphy.

5. At this stage, slope and basin sections are correlated together at high confidence and resolution, however have no sequence stratigraphic significance or interpretation. Thus, platform-top sections were correlated to slope/basin sections using the established polarity reversal framework and the coarse age control and regional stratigraphic context provided by the linkage to the ‘Classic Face’. The stacking pattern-based interpretations and systems tract calibration of the platform-top sections were then extrapolated to the slope and basin.

6. Once systems tracts were calibrated to slope and basin settings, rules and conceptual models for slope/basin sequence stratigraphy were generated using sediment



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T.E. PLAYTon ET AL.

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Figu

re7



References

BECKER, R.T. & HOUSE, M.R., 1997, Sea level changes in the Upper Devonian of the Canning Basin, Western Australia, Courier F orschungsinstitut S enckenberg, 199, 129–146.

BUGGISCH, W. & JOACHIMSKI, M.M., 2006, Carbon isotope stratigraphy of the Devonian of central and southern Europe, Palaeogeography, P alaeoclimatology, Palaeoecology, 240, 68–88.

COLLINS, J.F., KENTER, J.A.M., HARRIS, P.M., KUANYSHEVA, G., FISCHER, D.J. & STEFFEN, K.L., 2006, Facies and reservoir quality variations in the Late Visean to Bashkirian outer platform, rim, and flank of the Tengiz Buildup, Pricaspian Basin, Kazakhstan, in HARRIS, P.M. & WEBER, L.J. (Eds), Giant hydrocarbon reservoirs of the wor ld: F rom r ocks to r eservoir char acterization and modeling: American Association of Petroleum Geologists Memoir, 88, 55–95.

EJOFODOMI, E.A., YATES, M.E., DOWNIE, R., ITIBROUT, T., & CATOI, O.A., 2010, Improving well completion via real-time microseismic monitoring: a west Texas case study, Society of Petroleum Engineers Tight Gas Completions Conference, San Antonio, Texas, USA, 137996/14.

FROST, III, E.L. & KERANS, C., 2010, Controls on syndepositional fracture patterns, Devonian reef complexes, Canning Basin, Western Australia, Journal of Structural Geology, 32, 1231–1249.

GEORGE, A.D., PLAYFORD, P.E., POWELL, C.MCA. & TORNATORA, P.M., 1997, Lithofacies and sequence development on an Upper Devonian mixed carbonate-siliciclastic fore-reef slope, Canning Basin, Western Australia, Sedimentology, 44, 843–867.

GRADSTEIN, F.M. & OGG, J.G., 2004, Geologic Time Scale 2004; Why, how, and where next! Lethaia, 37, 2, 175–181.

HILLBUN, K., KATZ, D.A., PLAYTON, T.E., LEWARCH, E., TRINAJSTIC, K., TOHVER, E., HAINES, P., HANSMA, J., HOCKING, R., KIRSCHVINK, J., YAN, M., RATCLIFFE, K., PISAREVSKY, S., DUCEA, M., MONTGOMERY, P., HARRIS, P.M., & WARD, P., 2012, Stable isotope variations in Upper Devonian slope settings of the Lennard Shelf, Canning Basin, Western Australia: Implications for global environmental changes and impacts on carbonate development (abs), AAPG Annual Conference and Exhibition, Long Beach, California, USA.

KATZ, D.A., PLAYTON, T.E., BELLIAN, J.A., HARRIS, P.M., HARRISON, C. & MAHARAJA, A., 2010. Slope heterogeneity and production results in a steep-sided Upper Paleozoic isolated carbonate platform reservoir, Karachaganak Field, Kazakhstan, Society of P etroleum Engineers C aspian C arbonates Technology Confer ence, Atyrau, Kazakhstan, 139960/7.

• a composite stable inorganic carbon isotope curve for the Givetian through Famennian of the Lennard Shelf, to be compared with other semi-global Devonian composite curves (i.e. Europe, Buggisch & Joachimski, 2006) and incorporated into an overarching global secular reference curve; and

• a workflow for integrated chronostratigraphic correlation tailored to subsurface characterization, utilizing discontinuous core and cuttings.

Important components of the dataset have not yet been fully incorporated, such as magnetic susceptibility, elemental, biomarker, and outcrop gamma ray data. These data types can be generalized as either less understood in terms of controls on signal, or may be affected by highly localized phenomena – thus, naturally require a surrounding robust framework to examine within. The polarity-, conodont-, and global isotopic excursion-based framework provides a well-constrained template to examine and interpret these data within, and upon incorporation will undoubtedly add correlation resolution. Furthermore, inspection of regional versus local elemental and magnetic susceptibility signals will potentially advance our understanding of Devonian climate, and analysis of biomarkers and organics will generate conclusions on ocean circulation as linked to sea level changes and marine biotic crises.

Ergo, the geological implications of this study are vast, ranging from applied workflows for enhanced petroleum reservoir characterization, to unprecedented global chronostratigraphic references, to new carbonate shelf to basin predictive models, and finally, to better understanding of paleoclimate, paleo-oceanography, and extinctions. This study is an excellent example of an industry-academia-government-vendor collaboration that was successfully executed and produced significant results, for both applied and purely research purposes.

Acknowledgments

This high-level summary represents a large effort involving many groups over the course of several years. Funding was supplied by the Australian Research Council Linkage Program, MERIWA, WAERA, CSIRO, Buru, Chevron Australian Business Unit, Chevron Energy Technology Company, the University of Greenwich, and Chemostrat, Ltd. Field support and safety was provided by Wundargoodie Aboriginal Safaris (Colin and Maria Morgan and family/crew), the Geological Survey of Western Australia, and Steve Meyer and Sean O’Connell of Chevron. Thanks to Windjana Gorge National Park, Napier Downs, the Mimbi Community, Mount Pierre Station, Fossil Downs Station, Brooking Downs Station, the Pillara Mine, and the Cadjebut Mine for field area access and resources.


PLAYFORD, P.E., 1980, Devonian ‘great barrier reef ’ of the Canning Basin, Western Australia, AAPG Bulletin, 64, 814–840.

PLAYFORD, P.E., 1984, Platform-margin and marginal-slope relationships in Devonian reef complexes of the Canning Basin, in PURCELL, P.G. (Ed.), The Canning Basin: Proceedings of the Geological Society of Australia and Petroleum Exploration Society of Australia Symposium, Perth, WA, 1984, 189–214.

PLAYFORD, P.E., HOCKING, R.M., & COCKBAIN, A. E., 2009, Devonian reef complexes of the Canning Basin, Western Australia, Geological Survey of Western Australia Bulletin, 145/444.

PLAYTON, T.E., 2008, Characterization, variations, and controls of reef-rimmed carbonate foreslopes, PhD. thesis, The University of Texas at Austin, Austin, Texas.

PLAYTON, T.E., JANSON, X. & KERANS, C., 2010, Carbonate slopes,, in JAMES, N.P. & DALRYMPLE, R.W. (Eds), Facies Models 4: GEOtext 6, Geological Association of Canada, St. Johns, NL, Canada, 449–476.

KERANS, C., 1985, Petrology of Devonian and Carboniferous carbonates of the Canning and Bonaparte Basins, Western Australian Mining and Petroleum Research Institute Report, 12/203.

KERANS, C. & TINKER, S.W., 1997, Sequence stratigraphy and characterization of carbonate reservoirs, Society for Sedimentary Geology, Short Course Notes, 40/130.

KLAPPER, G., 2007, Frasnian (Upper Devonian) conodont succession at Horse Spring and correlative sections, Canning Basin, Western Australia, Journal of Paleontology, 81, 513–537.

JANSON, X., KERANS, C., LOUCKS, R., MARHX, M.A., REYES, C. & MURGUIA, F., 2011 Seismic architecture of a Lower Cretaceous platform-to-slope system, Santa Agueda and Poza Rica Fields, Mexico, AAPG Bulletin, 95, 105–146.

MONTGOMERY, S.L., 1996, Permian ‘Wolfcamp’ limestone reservoirs, Powell Ranch Field, eastern Midland Basin, AAPG Bulletin, 80, 1349–1365.

T.E. PLAYTon ET AL.



Ted P layton earned a BSc at the Colorado School of Mines, Golden, Colorado, USA, in Geological Engineering in 1998. There he studied Permian deep-water siliciclastic systems in West Texas outcrops. He then refocused on carbonates, earning MSc & PhD degrees from the University of Texas at Austin, Austin, Texas, USA, in 2003 & 2008, respectively, studying carbonate margin, slope, & basinal systems with Charlie Kerans. Since 2008, Ted has been with the Carbonate Stratigraphy R&D group at Chevron Energy Technology Company in Houston, Texas, USA. His projects at Chevron have included carbonate shelf-to-basin integrated chronostratigraphy (including Devonian Canning Basin outcrops), characterization of giant oil fields in Kazakhstan, reservoir modeling of carbonate ramps, classification of unconventional carbonate systems, and digital carbonate outcrop database development.

Biographies

Paul Montgomery graduated from the University of Birmingham with an honours degree in Geological Science in 1987 and a master degree in Engineering Geology from Durham University in 1988. He went on to gain his PhD on the Magnetostratigraphy of Cretaceous Chalk of southern England from the University of Southampton in 1995. After conducting stratigraphic research at the University of East Anglia and the University of Kansas, Paul joined Chevron as stratigrapher in 2002 working in the USA, Australia and the UK on carbonate and clastic reservoirs. He is currently located in Aberdeen working as a stratigrapher for the Chevron Upstream Europe and is an Adjunct Research Fellow in the Department of Geological Sciences & Geography, University of Western Australia.

Peter Haines graduated with Honours (1982) and PhD (1987) degrees in geology from the University of Adelaide, specialising in sedimentology and stratigraphy. He has previously held positions at the Northern Territory Geological Survey and Universities of South Australia, Adelaide and Tasmania. He joined the Geological Survey of Western Australia in 2003, currently holding a senior geologist position with the Basins and Energy Geoscience team where he has worked on the stratigraphy, sedimentology and petroleum potential of the Canning, Officer and Amadeus basins. He is a member of PESA, the Geological Society of Australia and the American Geophysical Union.

Ken Ratcliffe graduated from Imperial College in London with a BSc (Hons) in geology and subsequently gained a PhD from the University of Aston in Birmingham. Following a period working as a lecturer at Kingston University, Ken moved in the oil and gas industry, where in 2002 he co-founded Chemostrat, the company that Ken has continued to develop until the present day. In addition to running a successful consultancy company, Ken’s maintains a high rese4rach profile, with his main areas of interest being the development of innovative stratigraphic techniques and how they are best applied to the oil and gas industry. He has over 20 peer reviewed publications, regularly presenting papers at scientific conferences and is a member of the AAPG, SEPM and PESA

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