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Volume 3, No. 2June 2005

INSIDE: NEW APPROACHES TO UNDERSTANDING THE MECHANICSOF BURGESS SHALE-TYPE DEPOSITS

PLUS: PRESIDENT’S OBSERVATIONSCOMMENTS FROM THE COUNCILCALGARY ACTIVITIES

A publication of SEPM Society for Sedimentary GeologyA publication of SEPM Society for Sedimentary Geology

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Carbonate Sedimentology and Sequence StratigraphyBy: Wolfgang SchlagerSedimentology and stratigraphy are neighbors yet distinctly separate entities within theearth sciences. Sedimentology searches for the common traits of sedimentary rocksregardless of age as it reconstructs environments and processes of deposition and erosionfrom the sediment record. Stratigraphy, by contrast, concentrates on changes with time, onmeasuring time and correlating coeval events. Sequence stratigraphy straddles the bound-ary between the two fields. This book, dedicated to carbonate rocks, approaches sequencestratigraphy from its sedimentologic background. Carbonate sedimentation, in contrast tosiliciclastic, is largely governed by chemistry and biota of the ocean and thus intimately tiedto the ocean environment. Therefore, the presentation starts with essentials of physical andchemical oceanography and biology. It then proceeds to principles of marine carbonateproduction (and erosion) and the geometry of carbonate accumulations, using the conceptof carbonate production systems, or factories, to illustrate the variations among thecarbonate rocks. Next it turns to carbonate facies and the sedimentologic part closes withan overview of the rhythms and events governing carbonate depostion in time and space.Sequence stratigraphy starts with Chapter 6 with an overview then develops carbonatesequence stratigraphy on the basis of processes and principles presented in the sedimento-logic part. This book attempts to communicate by combining different specialities anddifferent lines of reasoning, and by searching for principles underlying the bewilderingdiversity of carbonate rocks. It provides enough general background, in introductorychapters and appendices, to be easily digestible for sedimentologists and stratigraphers aswell as earth scientists at large.

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The Sedimentary Record (ISSN 1543-8740) is published quarterly by theSociety for Sedimentary Geology with offices at 6128 East 38th Street,Suite 308,Tulsa, OK 74135-5814, USA.

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4 New Approaches to Understanding theMechanics of Burgess Shale-type Deposits:From the Micron Scale to the Global Picture

9 President’s ObservationsA Year in Review: A Society Moving Forward

10 Comments from the CouncilFirst Joint SEPM/GSL Research Conference inSeismic Geomorphology is a Huge Success

CONTENTS

EditorsLoren E. Babcock, Department of Geological Sciences, The Ohio State University, Columbus, Ohio 43210 <babcock.5@osu.edu>Stephen A. Leslie, Department of Earth Science, University ofArkansas at Little Rock, Little Rock, Arkansas 72204<saleslie@ualr.edu>Marilyn D. Wegweiser, Bucking Dinosaur Consulting; P.O. Box 243; Powell, WY, 82435; <thedoc@180com.net> <wegwmari@isu.edu>

SEPM Staff6128 East 38th Street, Suite #308,Tulsa, OK 74135-5814Phone (North America): 800-865-9765 Phone (International): 918-610-3361

Dr. Howard Harper, Executive Director<hharper@sepm.org> Theresa Scott, Business Manager<tscott@sepm.org>Bob Clarke, Publications Coordinator<rclarke@sepm.org>Michele Woods, Membership Services Associate<mwoods@sepm.org>

SEPM CouncilJ. Frederick Sarg, President<ricksarg1@aol.com>William A. Morgan, President-Elect<w.a.morgan@conocophillips.com>Lesli J. Wood, Secretary-Treasurer<lesli.wood@beg.utexas.edu>Serge P. Berne, International Councilor<sberne@ifremer.fr>Stephen A. Leslie, Councilor for Paleontology<saleslie@ualr.edu>Maria Mutti, Councilor for Sedimentology<mmutti@geo.uni-potsdam.de>Vitor Abreu, Councilor for Research Activities<vitor.abreu@exxonmobil.com>Kitty Lou Milliken, Co-editor, JSR<kittym@mail.utexas.edu>Colin P. North, Co-editor, JSR<c.p.north@abdn.ac.uk>Christopher G. Maples, Editor, PALAIOS<chris.maples@dri.edu>Laura J. Crossey, Editor, Special Publications<lcrossey@unm.edu>Tim Carr, President, SEPM Foundation<tcarr@kgs.ku.edu>

www.sepm.org

SEPM Members, please note that Judy Tarpley and Kris Farnsworth have

both left SEPM for other opportunities.We thank them for their dedicated serviceand for making their departure a smoothtransition. SEPM also looks forward tohaving Bob Clarke join the staff as the

new Publications Co-ordinator.

On the Cover: Bedding plane assemblage of sponges belonging to theGenus Choia from the middle Cambrian Wheeler Formation ofUtah, a Burgess Shale-type deposit. The host mudrocks may reveal awealth of data about the paleoenvironements of such deposits, theecology of the organisms, and the conditions which faciltiated theexquisite preservation. (Scale: The central disc of each sponge is 9-16 mm in diameter.) Photo by R. Gaines.

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BURGESS SHALE-TYPEDEPOSITS:THE GLOBALPICTURECambrian lagerstätten (Conway Morris, 1989)provide a fortuitous window into one of themost dramatic episodes in evolutionary histo-ry. Represented most famously by the BurgessShale (middle Cambrian of British Columbia),these deposits are noteworthy for two majorreasons. First, they provide an excellent recordof ancient biodiversity because they containfossils that are not preserved under normal cir-cumstances. Whereas the “normal” fossilrecord is almost exclusively a record of hard,mineralized skeletal parts, these deposits pre-serve some labile, nonmineralized tissues oforganisms, including those lacking hard skele-tal parts. Secondly, these deposits, which arerare in the geologic record as a whole, aremoderately abundant in lower and middleCambrian strata, an interval spanning the

time of the “Cambrian explosion.” In therock record, this interval is marked by the rela-tively sudden appearance of fossils represent-ing most animal phyla, the acquisition ofskeletal hard parts by a number of animalgroups, and the advent of predation and com-plex metazoan in ecosystems (e.g., Seilacher,1997; Zhuravlev and Riding, 2001; Babcock,2003). In this paper, we present a unifiedframework for understanding the dynamicinterplay of sedimentological, paleoecological,and paleoenvironmental factors that con-trolled the preservation and distribution offossils in a single Burgess Shale-type deposit,the Wheeler Formation (middle Cambrian) ofwestern Utah.

NEW APPROACHESMany BST deposits, including the WheelerFormation and the Burgess Shale, representdeposition just offshore of broad carbonate

platforms, at sharp shelf-slope breaks (ConwayMorris, 1998; Rees, 1986). Classic models forthe Burgess Shale have considered the deposi-tional environment to be fully anoxic, due tothe exquisite preservation of fossils, and thedark color of the mudrocks (e.g., ConwayMorris, 1986). This implies that the faunaswere transported, yet some assemblages of fos-sils, such as the well-known Ogygopsis trilobitebeds in the Burgess Shale and horizons thatcontain delicate sponges, clearly occur in situ.Important questions, key to a first-orderunderstanding the biotas in an ecologicalsense, have remained: Can discrete, paleoeco-logically meaningful assemblages be resolvedfrom within the homogeneous sediments?Were bottom water oxygen conditions suffi-cient to permit episodic, frequent, or sustainedbenthic colonization by in situ faunas?Because of the extraordinary importance ofthese biotas, a better knowledge of the rela-tionships of the organisms to the paleoenvi-ronments that they inhabited and/or facilitat-ed their preservation is desirable.

In order to begin to address these interrelat-ed problems, we focused on the middleCambrian Wheeler Formation of westernUtah, which contains abundant Burgess Shale-type preservation of nonmineralized fossils,including common macroscopic algae and adiverse fauna of more than 20 genera of morerarely occurring arthropods, priapulids,sponges, and cnidarians (Robison, 1991). Italso contains a well-described and diverseskeletal fauna (Robison, 1964, 1991). The for-mation is well exposed and readily accessibleover a broad area in the House Range (39°15’N, 113°20’ W) and immediate vicinity. Thestudy area is arid and also has not been sub-jected to extensive compressive stress. As aresult, mudrocks of the Wheeler Formationare less strongly altered by the effects of tec-tonics and weathering than are other impor-tant BST deposits.

Mudrocks present unique challenges tostudy. Unlike other types of sedimentary rocksthat are more readily interpreted in the field,mudrocks most often appear featureless andmassive. Thus, in a stratigraphic context,mudrocks are commonly interpreted to repre-sent static, monotonous conditions, or areoccasionally subdivided on the superficial basisof color. Mudrocks comprise the bulk (60%)of the sedimentary record, yet remain poorlyunderstood (Potter et al., 1980). However,recent methodological advances in the studyof mudrocks have demonstrated that inten-sive, fine-scale approaches can yield muchinformation about depositional processes andpaleoenvironments (e.g., Schieber 2003). The

New Approaches toUnderstanding theMechanics of BurgessShale-type Deposits:From the Micron Scale tothe Global PictureRobert R. Gaines, Department of Geology, Pomona College, Claremont, CA 91711;

robert.gaines@pomona.eduMary L. Droser, Department of Earth Sciences-036, University of California,

Riverside, CA 92521

ABSTRACTCambrian Burgess Shale-type (BST) deposits are among the most significant deposits forunderstanding the “Cambrian explosion” because they contain the fossilized tissues ofnonmineralized organisms and provide a substantially different window on the radiationof the Metazoa than is afforded by the more “typical” fossil record of skeletal parts ofbiomineralized organisms. Despite nearly a century of research, BST deposits remainpoorly investigated as sedimentologic entities largely because they comprise fine-grainedmudrocks. Here, we describe a new, integrative approach to understanding a single BSTdeposit, the middle Cambrian Wheeler Formation of Utah, which reveals a dynamicinterplay of paleoenvironmental, paleoecologic, and sedimentologic/diagentic factorswithin a superficially homogeneous lithofacies.This millimeter-scale microstratigraphicand paleontologic approach is augmented by both outcrop and microscopic study.Thesetypes of data are applicable to issues of quite different scales, including micron-scale dia-genetic processes involved in fossil preservation, organism-environment interactions andpaleoecology of the early Metazoa, and regional and global controls on the distributionof BST deposits.

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suite of depositional environments representedby mudrocks is typically characterized by low-energy deposition, relatively continuous sedi-mentation, and, often, little current reworkingin comparison to coarser-grained deposits.Furthermore, mudrocks often contain in situfossil assemblages, making them particularlygood candidates for paleoecological and pale-oenvironmental study.

An integrative, millimeter-scale, methodol-ogy, incorporating aspects of sedimentologyand paleontology was applied. In the field,short (1-5 m) intervals were targeted for inten-sive study and sampled continuously in dupli-cate. In the laboratory, these short sectionswere reconstructed and slabbed parallel tobedding, then etched lightly with dilute HClto reveal primary and secondary sedimentaryfeatures. Using direct analysis of the slabbedsamples in combination with thin sectionstudy, the sections were logged on a millimeterscale. The duplicate sets of samples were splitalong bedding planes for paleontologicalanalysis, and the microstratigraphic positionsof fossils were incorporated into the logs.These techniques were complemented bycompositional (XRD, EDX, coulometry), geo-chemical (δ13C; δ18O), microscopic (SEM, flu-orescent light, cathodoluminescent), andimaging (X-ray) analyses.

PALEOENVIRONMENTSAND BOTTOM-WATEROXYGENThe Wheeler Formation accumulated in whathas been interpreted as a fault-boundedtrough, termed the House Range embayment,at the edge of an expansive carbonate platform(Rees, 1986). At most localities, the WheelerFormation is composed of homogenous, fine-grained mudrocks, with smaller thicknesses ofthin-bedded, fine-grained carbonates. BurgessShale-type biotas occur only in the mudrockfacies. Wheeler mudrocks, which represent thelowest energy deposits found in the region,represent deposition in a basin adjacent to thedistal end of a carbonate ramp (Rees, 1986).The thin-bedded carbonates and interbeddedmudrocks comprising the distal ramp facies ofthe House Range embayment consist of sub-millimeter-thick micro-graded beds, interpret-ed to represent down-ramp gravity flowsdeposited below the influence of storm waves(Elrick and Hinnov, 1996). The basinalmudrock facies typically grades upwards intodistal ramp deposits. Basinal mudrock sedi-ments of the Wheeler Formation are charac-terized by: 1, exclusively fine grain size (<50µ);2, mixed carbonate-clay composition (17-47wt. % carbonate); 3, color-graded gray-black

“couplets” ranging from 1 to 12 mm in thick-ness, with no apparent size or compositionalgrading; and 4, uninterrupted vertical persist-ence for tens of meters of section, indicatingsustained low-energy deposition below theinfluence of storm waves. The “couplets” ofthe Wheeler Formation are interpreted as thedistal expression of gravity-dominated deposi-tional events spilling off of the adjacent ramp-however, they also may contain a hemipelagiccomponent. Some evidence for bottom-flow-ing currents is present, including transported(see below) and current aligned fossils (Rees,1986), and rare tool marks.

The availability or lack of dissolved oxygenin bottom waters during deposition is a criti-cal issue. In order to assess paleo-redox condi-tions, an ichnological model was applied(Savrda and Bottjer, 1986), which correlatesincreasing depth and extent of bioturbation toincreasing availability of dissolved oxygen ofbottom waters. In modern environments,anoxic conditions are characterized by a com-plete absence of bioturbation (ichnofabricindex (i.i.)1), whereas well-oxygenated envi-ronments are characterized by well-developedichnofabrics (i.i.4-5), and destruction of most

primary sedimentary structures (Savrda et al.1984). Extrapolating ichnological models toCambrian sediments requires caution, becausethe infaunal habitat was incompletely devel-oped at this time (Droser and Bottjer, 1988).Thus, this model was used as a relative tool, tocompare oxygen levels among beds within theWheeler Formation. This model was appliedon a bed-to-bed basis in order to develop rela-tive oxygen curves at a millimeter scale foreach of the continuously sampled intervals.The Wheeler Formation is inferred to havehad a complex redox history during deposi-tion, characterized largely by oxygen-deficientbottom water conditions that, at times, weresufficient to permit benthic colonization byepifaunal and infaunal organisms. Many sam-pled intervals show sustained bottom wateranoxia, whereas others show dynamic shiftsfrom inferred anoxic to dysoxic conditions at acentimeter to decimeter scale (Figure 1).

PALEOECOLOGYIn the >3000 individual beds analyzed,Burgess Shale-type preservation occurs exclu-sively in the absence of bioturbation (i.i.1).Thus, it is inferred that in the Wheeler

Figure 1. Microstratigraphic logs from the Wheeler Formation illustrating the context of nonmineralizedpreservation. A. 10-cm interval with complete absence of bioturbation and Burgess Shale-typepreservation in most beds, typical of sustained anoxic benthic conditions in the Wheeler Formation. B.20-cm interval showing cm-scale oscillations in bioturbation, bottom water oxygen, and, accordingly,fossil content. Most nonmineralized metazoan fossils occur where favorable preservational environmentsare closely interbedded with other types of beds.

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Formation, this style of preservation occursonly under anoxic bottom waters, uninhabit-able by benthic metazoans. Whereas this find-ing offers little hope for the possibility ofresolving distinct ecological assemblages with-in the nonmineralized faunas, microstrati-graphic patterns provide some insight.Nonmineralized fossils occur along a gradientranging from abundant fragmented anddiminutive forms to larger and more completeforms, which occur in lower densities.Microstratigraphic proximity of any givenhorizon bearing nonmineralized preservationto bioturbated (oxic) horizons is a reliableindicator of what type of nonmineralizedassemblages will be present. Intervals repre-senting accumulation under sustained bottomwater anoxia contain nonmineralized preserva-tion of small and/or disarticulated forms,dominated by algae with rare metazoans, ineach individual bed, often through hundredsof sequential beds (Figure 1A). Intervals bear-ing nonmineralized preservation that areinterbedded closely (<10 cm) with bioturbated

horizons reflect oscillating bottom water oxy-gen content, and contain larger and morecomplete nonmineralized fossils, including asignificant proportion of metazoans (Figure1B). Thus, the observed gradient in size andarticulation of nonmineralized fossils isinferred to be related to distance of transport.Intervals characterized by sustained anoxiarepresent accumulation sites distal to theanoxic-oxic boundary, and thus, to habitablebenthic environments from which the non-mineralized fossils were sourced. Intervalsoccurring in close microstratigraphic proximi-ty to habitable benthic environments areinferred to represent accumulation sites proxi-mal to oxic benthic environments, and thuscontain larger and more complete forms (seeFigure 2). This proximal-distal gradient inBurgess Shale-type preservation ranges fromdistal environments to the edge of oxic benth-ic environments, where, most rarely, in situpreservation of nonmineralized forms doesoccur, when abrupt shifts to bottom wateranoxia coincide with burial of benthic forms.

Such occurrences provide the best hope ofunderstanding elements of the Burgess Shalebiota in an ecological context, and may besought for further study by targeting suchenvironments for search.

Although BST deposits are best known forthe nonmineralized fossils they preserve, mostalso contain diverse faunas of skeletonizedforms. In the Wheeler Formation, skele-tonized faunas are dominated by trilobites,and also include acrotretid brachiopods andechinoderms. The best-known fossil from theWheeler Formation is the trilobite Elrathiakingii, which is found in collections aroundthe world. Despite a narrow geographic range,E. kingii is sufficiently abundant to be distrib-uted commercially because it occurs in denseassociations of up to 500 complete individualsper m2, and it is typically coated with cone-in-cone calcite on the ventral side, allowing easyextraction from the rock. Microstratigraphicanalyses revealed that E. kingii occurs inmonospecific associations, although E. kingiicommonly occurs in hand samples with otherfaunas that occur on other bedding planes(Gaines and Droser, 2003). Microstratigraphicdata also reveal that most (93.6%) E. kingiioccurrences are in unbioturbated beds that arein close vertical proximity (mm-cm) to bedsbearing nonmineralized preservation, and alsoclosely adjoin beds that contain weak to mod-erate levels of bioturbation. Because it occursprominently at the transitions from bedsdeposited under anoxic conditions to thosedeposited under oxic conditions, it is inferredthat E. kingii occupied a niche habitat at theedge of oxygenated bottom waters, below theoxygen levels required to support an infauna(Gaines and Droser, 2003). This manner ofoccurrence is consistent with an “exaerobiczone” lifestyle (Savrda and Bottjer, 1987),indicating that E. kingii may have used sulfurbacteria as a primary food source.Chemoautotrophic sulfur bacteria occur inabundance at this boundary today, where freesulfides in anoxic bottom waters mix withminimally oxygenated bottom waters (Figure3). The ready availability of sulfur bacteria as afood source provides the most plausible expla-nation for adaptation to a marginal, oxygen-stressed habitat. Sulfur bacteria have been pro-posed as a primary food source for other trilo-bites (Fortey, 2000), and the morphology ofE. kingii is consistent with these interpreta-tions, as E. kingii possesses a number of attrib-utes considered advantageous for life in oxy-gen-depleted environments. This finding indi-cates that non-phototrophic-based ecosystemswere in place early in the history of animallife. E. kingii also serves as an excellent pale-

Figure 2. Paleoecological reconstruction of the Wheeler Formation showing bottom water oxygen controlover the distributions of fossils found in the basinal mudrock facies. Distal nonmineralized assemblagesare characterized by A, bedding planes covered in algae (fragmentary or small), some belonging to thegenera Marpolia and Morania. B. Peronopsis, and other agnostoid trilobites occur in all assemblages,indicative of a pelagic mode of life, unrelated to benthic conditions. Proximal nonmineralizedassemblages are characterized by larger and more complete fossils: C. Articulated carapace of aphyllocarid arthropod. D. Yuknessia simplex, a nonmineralized alga. E. Brachyaspidion microps, apelagic trilobite. F. Marpolia spissa, a nonmineralized alga. G. Undetermined metazoan showing guttract. Exaerobic assemblages contain Elrathia kingii (H), in addition to occasional pelagic fossils.Dysaerobic assemblages contain a more diverse skeletonized fauna, including: I. Asaphiscus wheeleri. J.Acrothele?, K. Alokistocare. L. Gogia spiralis (eocrinoid). M. Olenoides. Rarely, nonmineralizedpreservation occurs in situ when sharp shifts in bottom water oxygen content occur: N. Association ofChoia. All scale bars are 5 mm.

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oenvironmental indicator in the WheelerFormation, marking the transition betweenoxic and anoxic benthic conditions, otherwiseirresolvable in the field. The possibility thatthe exaerobic niche may have been occupiedin other Cambrian environments holds greatpaleoecological significance.

Both nonmineralized fossil assemblagesand E. kingii associations are characteristic ofspecific, yet different, bottom water oxygenconditions, and both occur in unbioturbated(i.i.1) beds. A third assemblage type, micros-tratigraphically distinct from horizons bearingnonmineralized preservation as well as fromthose bearing E. kingii, is characterized by thepresence of weak to moderate levels of biotur-bation (i.i. 2-3), interpreted to signify dysoxicconditions (Figure 2). This assemblage is dom-inated by large (>3 cm) trilobites, most promi-nently Asaphiscus wheeleri, and also includesacrotretid brachiopods and the eocrinoidGogia. Orientation and evidence from moltassemblages indicates that these faunas occurin situ, however in lower densities than eitherthe E. kingii or nonmineralized fossil associa-tions. Further bed-to-bed-scale work holds thepromise of resolving discrete paleoecologicalassociations within this assemblage. A signifi-cant fauna of pelagic trilobites is also found inthe Wheeler Formation, including a diverseassemblage of agnostoids (Robison, 1964).The diminutive non-agnostoid trilobitesJenkinsonia varga and Brachyaspidion micropsare also interpreted as pelagic on the basis ofbiofacies-crossing distributions and their com-mon presence in beds representing depositionunder uninhabitable (anoxic) benthic condi-tions.

We infer that benthic redox conditionsacted as a first-order control over fossil contentin the Wheeler Formation, regulating the pri-mary distributions of organisms as well astheir preservation (Figure 2). Importantly,while all three types of assemblages (nonmin-eralized, E. kingii, dysaerobic) may occurwithin a single, narrow microstratigraphicinterval (millimeters-centimeters) at the scaleof a hand-sample, they represent discrete asso-ciations that occurred under demonstrably dif-ferent benthic conditions.

PRESERVATIONSpecific mechanisms of nonmineralized fossilpreservation are a subject of some debate.Whereas mineral-replacement of some non-biomineralized tissues occurs in some deposits(e.g., Emu Bay Shale of Australia; Briggs andNedin, 1997; and Chengjiang deposit ofChina; Zhu et al., 2005), the most commontype of preservation of nonmineralized tissues

in BST deposits may be “Burgess Shale-typepreservation” (Butterfield, 1995, 2003) of fos-sils as two-dimensional carbon films, althoughassociated mineral films also may be present(Orr et al., 1998). Curiously, this type ofpreservation is insignificant as a means of pre-serving benthic faunas after the middleCambrian. While some types of mineralreplacement of non-biomineralized tissueshave been explained using actualistic models(e.g., Briggs and Kear, 1994), the causes of“Burgess Shale-type” preservation have typical-ly been addressed using theoretical models.

Butterfield (1995) proposed that highlyreactive clay minerals may have been com-monplace on continental margins during someintervals of time and facilitated Burgess Shale-type preservation through adsorption ofdecay-inducing enzymes. This hypothesis wasnot supported by a metamorphic study of theBurgess Shale (Powell, 2003), which conclud-ed that the original mineralogic compositionof that unit was not unusual, and did notinclude any highly-reactive mineral species.Petrovich (2001) suggested that, under sub-oxic conditions, iron ions (abundant in clay-rich marine sediments) are strongly adsorbedonto chitin and other organic biopolymers,and may have prevented decay of these selecttissues by coating them and thereby physicallyblocking the enzymatic action of microbialdecomposers. However, this model predictsthat such preservation should be common inclay-rich, oxygen-deficient strata throughoutthe Phanerozoic. Both models, which invokemolecular-scale chemical interactions, do notprovide comprehensive explanations of thisphenomenon, and are problematic for the rea-sons described above.

Data obtained though intensive study of theWheeler Formation were also applied towardsthe development of a new hypothesis for

Burgess Shale-type preservation (Gaines et al.,2005). This model unites micron-scale diage-netic processes involved in preservation withprimary physical features of the depositionalenvironment, allowing predictions to be readi-ly applied to testing in other deposits. BurgessShale-type preservation in the WheelerFormation uniformly occurs in exclusivelyfine-grained sediments, lacking silt, fecal pel-lets, skeletal microfossils, and coarser particles.The close proximity of the depositional envi-ronment to a carbonate platform resulted inmixed carbonate–clay sediments, and facilitat-ed ubiquitous early diagenetic carbonatecements characteristic of Wheeler mudrocks(Gaines et al., 2005). These cements occur asmicron-sized pore filling cements and cone-in-cone cements around pre-existing carbonates,including trilobite carapaces or micritic hori-zons. Isotopic (δ13C) and petrographic evi-dence indicates that cements were emplacedearly in the diagnetic history and were derivedfrom a detrital carbonate precursor (Gaines etal., 2005). This model proposes that preserva-tion of nonmineralized tissues in the WheelerFormation resulted from a combination ofinfluences that reduced permeability and thuslowered oxidant flux, which in turn may haveacted to restrict microbial decomposition ofsome nonmineralized tissues. The absence ofcoarse grains (>50 µm) and skeletonizedmicrofossils provided very low original porosi-ty. Near-bottom anoxia prevented sedimentirrigation by restriction of bioturbation.Reducing conditions near the sediment-waterinterface also may have acted to deflocculateaggregations of clay minerals, resulting in lowpermeability face-to-face contacts (Moon andHurst, 1984). Abundant early diagenetic pore-occluding carbonate cements are suggested tohave contributed significantly to occlusion ofremaining porosity, halting oxidant flux into

Figure 3. A. Schematic diagram illustrating the “exaerobic” concept of Savrda and Bottjer (1987).Movement of the anaerobic/dysaerobic boundary across the seafloor over time result in close interleavingof exaerobic beds with beds accumulated under anaerobic conditions, as well as under more oxicconditions, as shown in B, a 10-cm microstratigraphic log. (Triangles=cone-in-cone calcite;arrows=nonmineralized preservation; blue ovals = E. kingii nodules; “Squiggles”=burrows).

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the sediments, restricting microbial decompo-sition and facilitating carbonaceous preserva-tion of macrofossils. Fe-organic interactions(Petrovich, 2001) or clay-organic interactions(Butterfield, 1995) may have also operated at amolecular scale within the Wheeler sedimentsand thereby provided a favorable early burialenvironment at the micron scale and above.

TOWARDS A GLOBALPICTURE: REMAININGCHALLENGESIn the Wheeler Formation, several regionaland global factors were important in promot-ing the conditions described above, and thus,these factors may be relevant to the global dis-tribution of Burgess Shale-type deposits. First,the depositional environment occurred off-shore of a broad (~300 km) carbonate plat-form, which sequestered coarse siliciclasticsinboard, and resulted in exclusively fine-grained, mixed carbonate-siliciclastic sedi-ments with low original porosities and thepotential for early carbonate cementation.Relatively high sea levels and broad passivemargins of the middle Cambrian (Brasier andLindsay, 2001) were clearly an important fac-tor, resulting in the migration of this distaldepositional environment onto continentalcrust, where sediments have long-term preser-vation potential. Secondly, oxygen-limitedbottom waters that lay just outboard of theplatform margin were important in providinga close juxtaposition of anoxic and oxic benth-ic environments. The location of this bound-ary on the slope is also important as it pro-motes downslope transportation of organismsfrom the living environment to the (uninhab-itable) preservational environment, and, inthis case, it places the boundary over sedi-ments favorable to preservation, describedabove. The incursion of oxygen-deficientwater masses onto the slope at this time hasbeen linked to restricted seaways, tropical con-ditions, and transgressive episodes (Landing,2001). A third important aspect is the absenceof skeletal microfossils from the locus of depo-sition. In the Holocene, skeletal micro-organ-isms are particularly abundant in shelf edgesettings, and their abundance is positively cor-related with both porosity and permeability ofsediments (Kraemer et al., 2000), however, theoldest microfossil oozes do not occur until thelate Cambrian (Tolmacheva et al., 2001), indi-cating a rise in abundance only at this time.While these conclusions are drawn from a sin-gle deposit, these aspects of the WheelerFormation’s primary depositional environmentare the result of regional and global phenome-

na, and may be common to the Burgess Shale,as well as to other BST deposits.

Field-based and lab-intensive investigationsof other BST deposits, conducted at an appro-priate scale, may provide insight not availablefrom studies of individual taxa alone. Furtherstudies at this scale are needed. Additionally,the root causes of widespread oxygen deficien-cy in early and middle Cambrian slope envi-ronments warrant further investigation. Didthese conditions result from periodicallyenhanced flux of organic matter to theseafloor, restricted circulation under climaticoptima (Landing, 2001), low-lying continentsat tropical latitudes, or some combination ofthese and other factors? Finally, the paleoecol-ogy of these most diverse Cambrian faunasdeserves further study. These results suggestthat discrete associations of fossils withinapparently homogenous, fine-grained depositsmay be resolved at a fine scale and linked tospecific paleoenvironmental conditions. Whileresults from the Wheeler Formation indicatethat most nonmineralized faunas are trans-ported assemblages of limited ecologic utility,these results provide framework criteria fortheir evaluation and suggest that associatedassemblages of skeletonized fossils may pro-vide significant opportunity for in situ paleoe-cologic study. As Burgess Shale-type depositsshould be characterized by occurrence at ornear the benthic redox (anoxic-dysoxic)boundary, they also present an environmentalwindow in which to evaluate the possibilitythat the non-phototrophic, exaerobic lifestylemay have been widespread during the“Cambrian explosion.”

ACKNOWLEDGMENTSWe thank M. Kennedy and N. Hughes, whowere involved in discussions throughout thecourse of this work. Additionally, we thank S.Finnegan for assistance in the field, discussion,and comments on a previous draft of thismanuscript. This work benefited considerablyfrom helpful discussions with D. Briggs, N.Butterfield, S. Jensen, S. Peters, M.Prokopenko, C. Savrda, and J. Schieber, andfield advice from T. Abbott and G. Gunther.Additional thanks to G.H. Johnson, J. Filer,and C. Kneale. This paper was reviewed byJ.W. Hagadorn and one anonymous reviewer.

REFERENCES:Allison, P.A., and Briggs, D.E.G., 1993, Exceptional fossil record:

Distribution of soft-tissue preservation through the Phanerozoic:Geology, v. 21, p. 527-530.

Babcock, L.E., 2003, Trilobites in Paleozoic predator-prey systems, andtheir role in reorganization of early Paleozoic ecosystems, in Kelley,P.H., Kowalewski, M., and Hansen, T.A., eds., Predator-PreyInteractions in the Fossil Record, Kluwer Academic/PlenumPublishers, New York, p. 55-92.

Babcock, L.E., Zhang, W., and Leslie, S.A., 2001, The Chengjiang Biota:

Record of the Early Cambrian diversification of life and clues toexceptional preservation of fossils: GSA Today, v. 11, p. 4-9.

Brasier, M.D., and Lindsay, J.F., 2001, Did supercontinental amalgama-tion trigger the “Cambrian Explosion”?, in Zhuravlev, A.Y., andRiding, R., eds., The Ecology of the Cambrian Radiation, ColumbiaUniversity Press, New York, p. 69-89.

Briggs, D.E.G., and Kear, A. J., 1994, Decay and mineralization ofshrimps: Palaios, v. 9, p. 431-456.

Briggs, D.E.G., and Nedin, C., 1997, The taphonomy and affinities ofthe problematic fossil Myoscolex from the Lower Cambrian Emu BayShale of South Australia: Journal of Paleontology, v. 71, p. 22-32.

Butterfield, N.J., 1995, Secular distribution of Burgess Shale-type preser-vation: Lethaia, v. 28, p. 1-13.

Butterfield, N.J., 2003, Exceptional fossil preservation and the Cambrianexplosion: Integrative & Comparative Biology, v. 43, 166-177.

Conway Morris, S., 1986. The community structure of the MiddleCambrian phyllopod bed (Burgess Shale): Palaeontology, v. 29, p.423-467.

Conway Morris, S., 1989, The persistence of Burgess Shale-type faunas:implications for the evolution of deeper-water faunas: Transactions ofthe Royal Society of Edinburgh: Earth Sciences, v. 80, p. 271-283.

Conway Morris, S., 1998, The Crucible of Creation: Oxford UniversityPress, Oxford, 242 p.

Droser, M.L., and Bottjer, D.J., 1988, Trends in depth and extent of bio-turbation in Cambrian carbonate marine environments, westernUnited States: Geology, v. 16, p. 233-236.

Elrick, M., and Hinnov, L.A., 1996, Millennial-scale climate origins forstratification in Cambrian and Devonian deep-water rhythmites,western USA: Palaeogeography, Palaeoclimatology, Palaeoecology, v.123, p. 353-372.

Fortey, R., 2000, Olenid trilobites: The oldest known chemoautotrophicsymbionts?: Proceedings of the National Academy of Science, v. 97,p. 6574–6578

Gaines, R.R., and Droser, M.L., 2003, Paleoecology of the familiar trilo-bite Elrathia kingii: an early exaerobic zone inhabitant: Geology, v. 31,p. 941-944.

Gaines, R.R., Kennedy, M.J., and Droser, M.L., 2005, A new hypothesisfor organic preservation of Burgess Shale taxa in the middle CambrianWheeler Formation, House Range, Utah: Palaeoclimatology,Palaeogeography, Palaeoecology, v. 218.

Hagadorn, J.W., 2002, Burgess Shale-type localities: The global picture,in Bottjer, D.J., Etter, W., Hagadorn, J.W., and Tang, C.M., eds.,Exceptional Fossil Preservation, Columbia University Press, NewYork, p. 91-116.

Kraemer, L.M., Owen, R.M., and Dickens, G.R., 2000. Lithology of theupper gas hydrate zone, Blake Outer Ridge: a link between diatoms,porosity, and gas hydrate: Proceedings of the Ocean Drilling Program,Scientific Results, v. 164, p. 229-236.

Landing, E., 2001, “Burgess Biotas” and episodic slope and epiric seadysaerobia in the Late Precambrian-Paleozoic: Geological Society ofAmerica Abstracts with Programs, v. 33, p. 38.

Moon, C.F., and Hurst, C.W., 1984, Fabric of mud and shales: anoverview, in Stow, D.A.V., and Piper, D.J.W. (Eds.), Fine-grainedSediments, Geological Society Special Publication v. 15, p. 579-593.

Orr, P.J., Briggs, D.E.G., and Kearns, S.L., 1998, Cambrian BurgessShale animals replicated in clay minerals: Science, v. 281, p. 1173-1175.

Petrovich, R., 2001, Mechanisms of fossilization of the soft-bodied andlightly armored faunas of the Burgess Shale and of some other classi-cal localities: American Journal of Science, v. 3001, p. 683-726.

Potter, P.E., Maynard, J.B., and Pryor, W.A., 1980, Sedimentology ofShale. Springer-Verlag, New York, 306 p.

Powell, W., 2003, Greenschist-facies metamorphism of the Burgess Shaleand its implications for models of fossil formation and preservation:Canadian Journal of Earth Sciences, v. 40, p. 13-25.

Rees, M.N., 1986. A fault-controlled trough through a carbonate plat-form: the middle Cambrian House Range embayment: GSA Bulletin,v. 97, p. 1054-1069.

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Robison, R.A., 1991, Middle Cambrian biotic diversity; examples fromfour Utah lagerstätten: in Simonetta, A.M., and Conway Morris, S.,eds., The Early Evolution of the Metazoa and the Significance ofProblematic Taxa, Cambridge University Press, Cambridge, p. 77-98.

Savrda, C.E., and Bottjer, D.J., 1986, Trace-fossil model for reconstruc-tion of paleo-oxygenation in bottom waters: Geology, v. 14, p. 306-309.

Savrda, C.E., and Bottjer, D.J., 1987, The exaerobic zone, a new oxygen-deficient marine biofacies: Nature, v. 327, p. 54-56.

Savrda, C.E., Bottjer, D.J., and Gorsline, D.S., 1984, Development of acomprehensive oxygen-deficient marine biofacies model: evidencefrom Santa Monica, San Pedro, and Santa Barbara Basins, Californiacontinental borderland: American Association of PetroleumGeologists Bulletin, v. 68, p. 1179-1192.

Schieber, J., 2003, Simple gifts and buried treasures- Implications of find-ing bioturbation and erosion surfaces in black shales: TheSedimentary Record, v. 1, p. 4-8.

Seilacher, A., 1997, The meaning of the Cambrian explosion: Bulletin ofthe National Museum of Natural Science, Taiwan, v. 10, p. 1-10.

Tolmacheva, T.J., Danelian, T., and Popov, L.E., 2001, Evidence for 15m.y. of continuous deep-sea biogenic siliceous sedimentation in earlyPaleozoic oceans: Geology, v. 29, p. 755-758.

Zhu, M.Y., Babcock, L.E., and Steiner, M., 2005, Fossilization modes inthe Chengjiang Lagerstätte (Cambrian of China): testing the roles oforganic preservation and diagenetic alteration in exceptional preserva-tion: Palaeogeography, Palaeoclimatology, Palaeoecology, 218.

Zhuravlev, A.Y., and Riding, R., eds., 2001, The Ecology of theCambrian Radiation: Columbia University Press, New York, 525 p.

The Sedimentary Record

Now that I am completing my term as yourPresident, I would like to take this last letter tobring you all up to date on the Society’sprogress over the past year. I think that SEPMhas had a good year, and there is much posi-tive to report. It has been a privilege andhonor to serve as SEPM President, and Iwould like to thank all of you who have vol-unteered to help the Society. It has been grati-fying to see how many of you have been will-ing to step up to serve. Headquarters is acommitted group and they have done a greatjob this past year. Our strength, however, is inour member volunteers who give the Society atruly strong presence in the SedimentaryCommunity.

Financially, these are challenging times forall professional societies, and Headquartersand the HBC Committee, chaired by JohnRobinson, have teamed up to achieve a year inthe black for SEPM. In the uncertain worldof revenues and publishing, this is a significantachievement.

We, as a Society, have made significantstrides in the last year on a number of ongoingefforts that past Councils and Headquartershave initiated. We have seen the successfullaunch of GSW (GeoScience World) in thefirst quarter of this year. Thirty geosciencejournals have partnered to create a singleresource for geoscience researchers. It shouldbe coming to your local geoscience library orcompany soon. I am optimistic that that ourparticipation in this publishing aggregate willgive us a growing, and stable source ofincome. The aggregate approach to publica-tion should allow significant savings forlibraries, and ensure that SEPM journalsremain in geoscience libraries. This has takenup a great deal of Howard’s time over the lasttwo years and he is to be commended on a jobwell done. As the internet continues tochange the world around us, more changes arecoming in the publishing world. Digital pub-lishing is here to stay. Open access is, I pre-dict, going to come faster than we think. Ourjournals are considering moving to an all-elec-tronic venue. It is time now to express yourviews to your editors. This will be a topic ofdiscussion at the next Council meeting in

Calgary, this June.We have continued to strengthen our global

community. The Sedimentary Record hasreceived excellent feedback from members,and continues to grow into an effective venuefor keeping you all informed and connected toSEPM. Our partnerships with AAPG andGSA have been strengthened. We had astronger presence at GSA in Denver last fall,and I expect our participation will grow. Theprogram for Calgary this year, in partnershipwith the CSPG, is shaping up to be an excel-lent one. In addition to strong technical ses-sions, I think we will have the strongest line-up of short courses and field trips that I haveseen in some time. Don’t forget to check themembership box when you register forCalgary, so that SEPM can get credit andreceive funds from AAPG to help defer themeeting costs. Under the leadership of JohnSnedden and Brad Prather, next year’s AnnualMeeting in Houston looks strong as well.Highlights will include a core workshop ongiant fields from around the world, and ashort course workshop on Quaternary reefsand platforms – bridging the gap between theancient and the modern. On the internationalfront, SEPM has agreed to sponsor events attwo upcoming meetings. We will be sponsor-ing student participants at the 8thInternational Conference on FluvialSedimentology, to be held in the Netherlandsin August of this year. At the AAPG/PESAInternational Meeting in Perth in 2006, wewill sponsor two technical sessions, an oral ses-sion on carbonate platforms and a poster ses-sion on coastal and shelf processes, a sequencestratigraphy short course for students, andpossibly a field trip to the Great Barrier Reef.I see this as a start to bringing more value toour members around the world.

Lastly, I’d like to mention our ResearchConferences. These are, of course, a vital ele-ment in our efforts to disseminate our science,and I am happy to report that we are in themidst of an excellent year. Due to the effortsof Howard, and Vitor Abreu and the ResearchCommittee, we have been able to increase thenumber conferences, and the diversity of con-ference topics. Since last year’s annual meet-

ing in Dallas, SEPM has conducted three verysuccessful research conferences, all of whichwill result in special publications.Conferences have included: (1) RecentAdvances in Shoreline – Shelf Stratigraphy,organized by Gary Hampson, Ron Steel, PeteBurgess, and Bob Dalrymple; (2) SeismicGeomorphology, organized by Lesli Wood,Vicki Sare, Richard Davies, Joe Cartwright,and Henry Posamentier; and (3) GeologicProblem Solving with Microfossils, hosted andorganized by NAMS, and led by TomDemchuk, and Ron Waszczak. I was able toattend the Seismic GeomorphologyConference, and was impressed with the quali-ty of oral presentations and posters, and thelively discussions among participants. TheSeismic Geomorphology special publicationwill be published in partnership with theGeological Society of London, who co-spon-sored the conference. Our next research con-ference will be held in May, in SpringfieldMissouri, on The Sedimentary Record ofMeteorite Impacts. Future topics that havebeen approved or are in review include, 1)External Controls on Deep Water Deposition;2) Ichnological Applications toSedimentologic and Stratigraphic Problems; 3)Application of Earth System Modeling toExploration; 4) Paleogeography,Paleoclimatology and GIS; 5) Sea Levels; and6) Source2Sink – Mississippi River System(Quaternary). I want to thank all the organiz-ers for their efforts this past year, and wishsuccess to all our upcoming conveners. Whenyou consider the list above, it is clear that wehave a very diverse and healthy sedimentarycommunity.

I encourage you all to stay involved, and ifyou haven’t volunteered yet, please considerhelping out. It has been fun for me, and I canhighly recommend it. Once again, I want tothank you, the members, for allowing me toserve as your President. I am looking forwardto staying involved with SEPM as your Past-President.

Rick Sarg, President SEPMricksarg1@aol.com

PRESIDENT’S OBSERVATIONS

A YEAR IN REVIEWA Society Moving Forward

June 2005 | 9

COMMENTS FROM THE COUNCIL

The Sedimentary Record

10 | June 2005

The first joint SEPM Society forSedimentary Geology & Geological Societyof London (GSL) Research Conference inSeismic Geomorphology was held February10 and 11 at the Westchase Hilton inHouston, Texas. Over one hundred andforty attendees enjoyed two days of key notespeakers, technical talks and posters and net-working lunches that brought together theindustry, government and academic scien-tists who are exploring this new direction insedimentary systems study. Dr. HenryPosamentier (Chief Geologist, Anadarko)kicked off the conference with a key noteaddress reviewing the history and future ofseismic geomorphology. His talk was wellreceived by all, setting the tone of the con-ference as a move toward the future that isbuilt upon the strong historic scientificdirections of seismic stratigraphy, sequencestratigraphy and sedimentary geomorpholo-gy. Other key note speakers included Dr.

Frank Ethridge (Colorado State University,USA), Dr. John Anderson (Rice University,USA) and Dr Fridtjof Riis (NorwegianPetroleum Directorate). The sessionsfocused on deep marine, shallow marine andfluvial systems and carbonates. In addition,sessions with specific exploration and devel-opment case studies and new methods inseismic analysis and visualizations roundedout the two-day program. Participants com-mented that “the conference was superb. Itwas good to see that SeismicGeomorphology has moved on from a col-lection of fancy pictures to some quantitativeanalysis.” Several attendees observed that itwas good to see this number of talks illus-trating how seismic techniques/seismic geo-morphology can actually be applied to “real-life” exploration and production issues. Apublication from the conference is slated tocontain at least 18 papers and be out by early2006. It will be jointly produced by SEPM

and GSL and be officially published as aGSL Special Publication.

Conference co-conveners includedRichard Davies and Joe Cartwright (CardiffUniversity), Lesli Wood (Bureau ofEconomic Geology, University of Texas atAustin), Henry Posamentier, and Vicki Sare(ChevronTexaco). The conference organiz-ers SEPM and GSL would like to thank theconference sponsors, Paradigm Geophysics,BP, Anadarko Algeria Company LLC andthe Quantitative Seismic GeomorphologyResearch Group at the University of Texas atAustin for their financial support of thisimportant scientific collaborative effort bySEPM and GSL. We hope that these typesof collaborations will continue in the future.

Lesli Wood, SEPM Sectretary-Treasurerlesli.wood@beg.utexas.edu

First Joint SEPM/GSL Research Conference inSeismic Geomorphology is a Huge Success

SEPM SOCIETY FOR SEDIMENTARY GEOLOGY 2005NEW COUNCIL MEMBERS

PRESIDENT-ELECT: ROBERT DALRYMPLE, Queens University, Ontario, CanadaSEDIMENTOLOGY COUNCILOR: RONALD STEEL, Univ. of Texas-Austin, Texas, USAPALEONTOLOGY COUNCILOR: STEVEN HOLLAND, Univ. of Georgia, Georgia, USASPECIAL PUBLICATIONS CO-EDITORS: LAURA CROSSEY, Univ. of New Mexico, New Mexico, USA

DONALD McNEILL, Univ. of Miami, Florida, USA

…and thanks to the outgoing council members for their serviceRick Sarg (Exxonmobil-retired) Maria Mutti (Univ. of Pottsdam)Stephen Leslie(Univ. of Arkansas, Little Rock)

….and welcome to potential volunteer members

SEPM is always in need of member volunteers for standing committees and ad hoc special assignments.If you are interested in helping SEPM in its activities please contact: Bill Morgan (SEPM President – w.a.morgan@conocophillips.com) or Howard Harper (Executive Director, hharper@sepm.org).

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

The Society for Organic Petrology (TSOP), 22nd Annual Meeting, September 11-14, 2005, Louisville, Kentucky USA. Information: Dr. James Hower, E-mail: hower@caer.uky.eduFurther details: http://igs.indiana.edu/tsop2005

The Sedimentary Record

June 2005 | 11

SiliciclasticsStratigrapher/Sedimentologist Houston TexasFocus: Fluvial, Lacustrine, Aeolian, Coastal, Shallow

Marine Siliciclastics • 0-15 years industry experience with MS/PhD

degree in Clastic Sedimentology/Stratigraphy. • Strong geoscience interpretation and workstation

skills (core, well log, regional scale analysis, seismic interpretation)

CarbonateStratigrapher/Sedimentologist Houston TexasFocus: Carbonates

and Diagenesis • 0-15 years industry experience with MS/PhD in

Carbonate Sedimentology/Stratigraphy • Demonstrated competence in understanding

carbonate deposition and diagenesis in asequence stratigraphic context.

e l e v a t e o p p o r t u n i t y

ConocoPhillips is seeking 3 geological specialists who will:Support global teams through application of stratigraphic principles to address questions of reservoir architecture and continuity; guide industrial andacademic research programs. Successful candidates need to quickly fit into multi-disciplinary teams, manage multiple projects, and influence businessdecisions as collaborative team players. Strong capability in integration of diverse geoscience data required. Some domestic/foreign travel required.

Petrographer/Petrologist Houston TexasFocus: Sedimentology, Diagenesis and Stratigraphy of Carbonate

and Siliciclastic Rocks • 0-15 years industry experience with MS/PhD in

Sedimentology/Stratigraphy• Knowledge of thin-section petrography, UV/cathodoluminescent

microscopy, XRD, SEM, electron probe, fluid inclusion, stableisotope and trace element analysis. Familiarity with coredescription and diagenetic software modeling packages.

Attractive salary and full-scale benefits program. Agency need not apply. An equal opportunity employer.Submit resumes via: Open Positions on http://www.conocophillips.com/careers

External controls on deep water depositional systems:climate, sea-level, and sediment flux.

Tentative dates: March 27-29, 2006, London, UK

Conveners: Ben Kneller (Aberdeen), Ole Martinsen (Norsk Hydro),Bill McCaffrey (Leeds) & Henry Posamentier (Anadarko Canada)

Deep marine clastic systems represent the planet’s ultimate sediment sink. As such, they are susceptible to allthe processes that govern sediment supply throughout the transport pathway, from uplift and erosion, throughfluvial transport, shoreline transition, storage and remobilization, each affected by tectonics, climate and sealevel. The deep marine system thus contains a record of these controls in its distribution of sediment typesand depositional architectures, which is more complete than that provided by any other depositionalenvironment. Moreover, it extends into the distant geological past, providing a record of climate change ontime scales two orders of magnitude greater than that of the Pleistocene, and including records of a verydifferent Earth from that of today.

The continuing importance of hydrocarbon reservoirs hosted by deep marine clastic systems also demands anunderstanding of the interplay of these external controls in generating suites of architectures that can bepredicted in the subsurface. Also existing oil and gas fields provide a wealth of stratigraphic and contextualinformation from which these controls can be elucidated.

The aim of the meeting is to promote cross-fertilization between workers on modern, subsurface and outcropsystems, and to highlight the application of concepts from climatology, the study of Quaternary variations insediment flux and type in rivers and on shelves etc, by having keynote speakers from these ‘outside’disciplines. There will also be invited speakers from within the discipline and a host of submitted topicalpresentations. Go to www.sepm.org or www.geolsoc.org.uk for additional information.

Upcoming GSL/SEPM Joint Research Conference

SEPM ACTIVITIES AT THECALGARY ANNUAL MEETING

(Please check at The Westin for specific room assignments – there is limited shuttle service to and from The Westin and Stampede Park as well as train service)

Sunday, June 19: SEPM Council Meeting – 8:00 am – 5:00 pm-The Westin CalgarySunday, June 19: SEPM Research Group – Hydro & Enviro Geology – 2:00 pm – 4:00 pm – Lake Louise RoomSunday, June 19: SEPM Research Group – Clastic Diagenesis – 2:00 pm – 4:00 pm – Rideau RoomSunday, June 19: SEPM Booth Ice Breaker – 5:00 pm – 7:30 pm – Stampede Park

Monday, June 20: SEPM Student Reception – 6:00 pm – 7:00 pm –The Westin CalgaryMonday, June 20: SEPM Research Group – Chronos/MMRG - 7:00 pm – 10:00 pm – To Be AnnouncedMonday, June 20: SEPM Research Group – Carbonate Research – 7:00 pm – 10:00 pm – Mayfair RoomMonday, June 20: SEPM Research Group – Paleosals – 7:00 pm – 10:00 pm – Lake Louise RoomMonday, June 20: SEPM Research Group – Sequence Stratigraphy – 7:00 pm – 10:00 pm – Lakeview RoomMonday, June 20: SEPM Research Group – Deep Water – 7:00 pm – 10:00 pm – Banff Room

Tuesday, June 21: SEPM Lunch with Dr. John Grotzinger (ticket required) – 11:30 am – 1:30 pm – The Westin CalgaryTuesday, June 21: SEPM Foundation Reception (by invitation) – 6:00 pm – 7:00 pm –The Westin CalgaryTuesday, June 21: SEPM President’s Awards Reception – 7:00 pm – 8:30 pm – The Westin Calgary

Please stop by the SEPM Booth #1509 at Stampede Park ! THANKS TO ALL OF THESEPM ANNUAL MEETINGSPONSORS

A & R Resources, LLCBPBurlington ResourcesChemostratConocoPhillipsDuvernay Oil Corp.ExxonMobil/Imperial Oil ResourcesGenesis Executive CorporationHuron Energy CorporationMidnight Oil Exploration - DaylightEnergy TrustPetroleum Place EnergyPriority Oil & Gas LLCRakhit Petroleum Consulting Ltd.Real Resources Inc.Suncor Energy Inc.Zargon Oil & Gas Ltd

A SPECIAL THANKS TO THE CALGARY SEPM ANNUAL MEETING COMMITTEEBrian Zaitlin -SEPM Vice ChairBob Dalrymple-SEPM Co-Vice ChairBrian Jones-SEPM Oral Session Co-ChairGuy Plint- SEPM Oral Session Co-ChairJames MacEachern-SEPM Poster Session ChairCindy Riediger-SEPM Short Course ChairDave Eberth-SEPM Field Trip ChairJeff Lukasik-SEPM Core Display ChairBruce Schulz-SEPM Sponsorship Chair A NEW SEPM SPONSORSHIP RECORD!

The committee would like to give there thanks to their colleagues on theAAPG Annual Meeting Committee and especially to Sarah Venance (CSPGAssistant Convention Manager), who has been a source of constant help.