Sequence Stratigraphy

Annual Reviews www.annualreviews.org/aronline Annu.Rev. EarthPlanet. Sci. 1995.23:451-78 Copyright(~ 1995by AnnualReviewsInc. All rights reserved Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCE STRATIGRAPHY Nicholas Christie-Blick and Neal W. Driscoll Departmentof Geological Sciences and Lamont-DohertyEarth Observatory of ColumbiaUniversity, Palisades, NewYork 10964-8000 KEYWORDS: sedimentation, unconformity, tectonics, seismic stratigraphy, sea level INTRODUCTION Sequencestratigraphy is the study of sedimentsand sedimentaryrocks in terms of repetitively arranged facies and associated stratal geometry(Vail 1987;Van Wagoneret al 1988, 1990; Christie-Blick 1991). It is a technique that can be traced back to the workof Sloss et al (1949), Sloss (1950, 1963), and Wheeler (1958) on interregional unconformitiesof the NorthAmericancraton, but it becamesystematizedonlyafter the advent of seismicstratigraphy, the stratigraphic interpretation of seismicreflection profiles (Vail et al 1977, 1984, 1991;Berg &Woolverton1985; Cross &Lessenger 1988; Sloss 1988; Christie-Blick et al 1990; Van Wagoneret al 1990; Vail 1992). Sequencestratigraphy makesuse of the fact that sedimentarysuccessions are pervadedby physical discontinuities. Theseare present at a great range of scales and they arise in a numberof quite different ways:for example,by fluvial incision and subaerial erosion (abovesea level); submergenceof nonmarineor shallow-marinesediments during transgression (flooding surfaces and drowningunconformities), in somecases with shoreface erosion (ravinement); shoreface erosion during regression; erosion in the marineenvironmentas a result of storms, currents, or mass-wasting;and through condensation under conditions of diminished sediment supply (intervals of sedimentstarvation). The mainattribute shared by virtually all of these discontinuities, independentof origin and scale, is that to a first approximation they separate older deposits from youngerones. The recognition of discontinuities is therefore useful because they allow sedimentarysuccessions to be divided into geometrical units that have time-stratigraphic and hence genetic significance. Precise correlation has of course long been a goal in sedimentarygeology, and the emergenceof sequence stratigraphy does not imply that existing techniques or data oughtto be discarded. Instead, sequencestratigraphy provides a 451 0084-6597/95/0515-0451$05.00 Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 452 CHRISTIE-BLICK& DRISCOLL unifying frameworkin whichobservationsof intrinsic properties such as lithology, fossil content, chemistry, magneticremanence,and age can be compared, correlated, and perhaps reevaluated. Withthe possible exception of sedimentar), units characterized by tabular layering over large areas and by the absence of significant facies variation (for example,somedeep-oceanicsediments), is hard to imagineattemptingto interpret the stratigraphic record in any other context. Wemakethis point because criticisms leveled at sequencestratigraphy havetended to lose sight of the essence of the technique. In this regard, it is unfortunate that the developmentof sequencestratigraphy has coincided with the reemergenceof the notion that in marine and marginal marine deposits sedimentary cyclicity is due primarily to eustatic change (Vail et al 1977; Haq et al 1987, 1988; Posamentieret al 1988; Sarg 1988; Dott 1992). Eustasy (global sea-level change) mayin fact have modulated sedimentationduring muchof earth history but, as a practical technique and in spite of terminologycurrently in use, sequencestratigraphy does not actually require any assumptionsabout eustasy (Christie-Blick 1991). Indeed, one of the principal frontiers of this discipline today is the attempt to understandpatterns of sediment transport and accumulation as a dynamic phenomenongoverned by a great manyinterrelated factors. In mostcases, specific attributes of sedimentarysuccessions(for example,the lateral extent and thickness of a sedimentaryunit, the distribution of included facies, or the existenceof a particular stratigraphic discontinuity) cannot be ascribed confidentlyto a single cause. In particular, the roles of"tectonic events," eustatic change, and variations in the supply of sediment can be partitioned only with difficulty (Officer &Drake1985, Schlanger1986, Burtonet al 1987, Cloetingh 1988, Kendall & Lerche 1988, Galloway 1989, Cathles & Hallam 1991, Christie-Blick 1991, Reynoldset al 1991, Sloss 1991, Underhill 1991, Kendallet al 1992, Karneret al 1993, Steckler et al 1993, Driscoll et al 1995). Eachof these factors operates at a broad range of time scales (cf Vail et al 1991), and none is truly independent owing to numerousfeedbacks. For example, the accumulation of sediment produces a load, which in manycases significantly modifies the tectonic componentof subsidence (Reynoldset al 1991, Steckler et al 1993, Driscoll & Karner 1994). The space available for sedimentto accumulateis therefore not simplya function of somepoorly defined combinationof subsidence and eustasy (the now-popularconcept of "relative sea-level change") because that space is influenced by the amountof sediment that actually accumulates. As a result of feedbacks, there are also inherent leads and lags in the sedimentary system; these influence the timing of the sedimentary response to any particular driving signal in waysthat are difficult to predict quantitatively (Jordan & Flemings 1991, Reynolds et al 1991, Steckler et al 1993). This phenomenon is particularly significant for efforts to sort out the role of eustasy Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCESTRATIGRAPHY 453 (e.g. Christie-Bliek 1990, Christie-Blick et a11990,Watkins&Mountain1990, Loutit 1992). If the phaserelation betweenthe eustatic signal and the resulting stratigraphic record varies from one place to another, then the synchronyor lack thereof of observedstratigraphic events mayprove to be less useful than previouslythought as a criterion for distinguishing eustasy fromother controls on sedimentation. At the very least, the.comparisonof sites needsto take into accountthe other importantvariables. Recognitionof these inherent difficulties has led to a gradualshift in research objectives awayfrom such goals as deriving a "sea-level curve," and toward studies designedto investigate the effects of specific factors ki~ownto have been important in governing sedimentation in a particular sedimentary basin or at a particular time in earth history. Among the most important factors are the rates and amplitudesof eustatic change,subsidencepatterns in tectonically active and inactive basins, sedimentflux or availability, the physiographyof the depositional surface (for example,rampsvs settings with a well-developed shelf-slope break), and scale. The subdiscipline of high-resolution sequence stratigraphy has emergedin the course of this research partly in response to the need for detailed reservoir stratigraphy in maturepetroleumprovinces and partly becausemanyof the interesting issues needto be addressedat an outcrop or boreholescale (meters to tens of meters) rather than at the scale of a conventional seismic reflection profile (Plint 1988, 1991; VanWagoneret al 1990, 1991; Jacquin et al 1991; Leckie et al 1991; Mitchum& Van Wagoner1991; Posamentier et al 1992a; Flint &Bryant 1993; Garcia-Mond6jar&Fern~indezMendiola 1993; Johnson 1994; Posamentier & Mutti 1994). Another frontier in sequencestratigraphy is the application of sequencestratigraphic principles to the study of pre-Mesozoic successions (e.g. Sarg &Lehmann1986; Lindsay 1987; Christie-Blick et al 1988, 1995; Grotzinger et al 1989; Sarg 1989; Ebdonet al 1990; Kerans &Nance 1991; Levy & Christie-Blick 1991; Winter & Brink 1991; Bowring& Grotzinger 1992; Holmes& Christie-Blick 1993; Lindsay et al 1993; Sonnenfeld & Cross 1993; Southgate et al 1993; Yang& Nio 1993). In spite of its roots in Paleozoicgeology(Sloss et a11949),sequence stratigraphy has been undertaken primarily in Mesozoicand Cenozoicdeposits owingto the greater economicsignificance, more complete preservation, and amenabilityto precise dating of sedimentsand sedimentaryrocks of these eras. However,applications to older successions within the past decadehave provided important new perspectives about the developmentof individual sedimentary basins, as well as data relevant to manyof the issues outlined above. Standard concepts and the basic methodologyof sequence stratigraphy are describedin numerous articles, especially those by Haqet al (1987), Vail (1987), Baum&Vail (1988), Loutit et al (1988), Van Wagoneret al (1988, 1990), Posamentieret al (1988), Sarg (1988), Haq(1991), and Vail et ai (1991). this review, we have chosento emphasizeareas of disagreementor controversy, Annual Reviews www.annualreviews.org/aronline 454 CHRISTIE-BLICK& DRISCOLL especially with respect to the origin of stratigraphic discontinuities, whichwe think is one of the mostinteresting general issues in sedimentarygeology. Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. CHOICE OF A FRAMEWORKFOR SEQUENCE STRATIGRAPHY The objective of sequencestratigraphy is to determinelayer by layer howsedimentarysuccessionsare put together, from the smallest elementsto the largest. Weare thus interested in all of the physical surfaces that at different scales separate one depositional element from another, and it could be argued that disagreements about how elements are defined and combinedare secondary to the overall task at hand. Indeed, different perceptions are in part a product of real differences that haveemergedin the study of contrasting examples. However,it is clear that stratigraphy represents morethan a series of random events. In manycases there exists a definite hierarchy in layering patterns. In choosing a frameworkfor sequence stratigraphy, it is therefore important to select elements that are as far as possible genetically coherent and not merely utilitarian. Currently, at least three schemesare being used (Figure 1). Here we briefly makethe case for the form of sequence stratigraphy that emerged from Exxonin the 1970s and 1980s (Vail et al 1977, 1984; Vail 1987; Sarg 1988; VanWagoneret al 1988, 1990), in preference to "genetic stratigraphy" (Galloway1989) and "allostratigraphy" (NACSN 1983, Salvador 1987, Walker 1990, Blum1993, Mutti et al 1994). Sequencestratigraphy and genetic stratigraphy differ primarily in the waythat fundamentaldepositional units are defined (Figure 1). In the case of sequence stratigraphy, the depositional sequenceis defined as a relatively conformable succession of genetically related strata boundedby unconformities and their correlative conformities (Mitchum1977, Van Wagoneret al 1990, ChristieBlick 1991). In the most general sense, an unconformityis a buried surface of erosion or nondeposition.In the context of sequencestratigraphy, it has been restricted to those surfacesthat are related (or are inferred to be related) at least locally to the loweringof depositional base level and henceto subaerial erosion or bypassing(Vail et al 1984, VanWagoneret al 1988). Accordingto this definition, intervals boundedby marineerosion surfaces that do not pass laterally into subaerial discontinuities are not sequences. The fundamentalunit of genetic stratigraphy, the genetic stratigraphic sequence,is boundedby intervals of sediment starvation (Galloway1989). Thesecorrespond approximatelywith times of maximum flooding and their significance is therefore quite different fromthat of subaerial erosion surfaces. Both kinds of sequence are recognizable in seismic reflection and borehole data. The principal argumentfor adoptingthe genetic stratigraphic approachis utilitarian: Intervals of sedimentstarvation are laterally persistent andpaleontologically useful. However,the boundariesof genetic stratigraphic sequencesare Annual Reviews www.annualreviews.org/aronline SEQUENCE STRATIGRAPHY A Genetic Stratigraphlc 455 Sequence Set Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. EXPLANATION Fluvial and Coastal Plain Shoreface and Deltaic Shelf and Slope Bas(nwardLimit of AIIoetratlgraphic Unit Submarine "Fan" CompositeInterval of Sediment Starvation Depositional SequenceBoundary B Genetic Stratigraphic ¯ Sequence Bounclery X Depositional SequenceBoundary Subaerial Hiatus ~ DISTANCE Figure 1 Conceptual cross sections in relation to depth (A) and geological time (B) showing stratal geometry, the distribution of siliciclastic facies, and competing schemes for stratigraphic subdivision in a basin with a shelf-slope break (from NACSN 1983, Galloway 1999, Vail 1987, Christie-Blick 199l, Vail et al 1991). Boundaries of depositional sequences are associated at least in places with subaerial hiatuses, and they are the primary stratigraphie disec~atinuities in a succession. Boundaries of genetic strafigraphic sequences are located within intervals of sediment starvation, and they tend to onlap depositional sequence boundaries toward the basin margin (point X). Allostratigraphic units are defined and identified on the basis of bounding discontinuities. Allostratigraphic nomenclature is not strictly applicable where a bou~tiing unconformity passes laterally into a conformity or where objective evidence for a stratigraphic discontinuity is lacking (basinward of points labeled Y ). located somewhat arbitrarily within more-or-less continuous successions. In somecases, no distinctive surfaces are present. In others, intervals of starvation may contain numerous marine disconformities or hardgrounds (lithified crusts, commordycomposed of caxbonate). Objective identification of the maximum flooding surface is usually difficult, and so genetic stratigraphy is especially limited in high-resolution subsurface and outcrop studies. Unduefocus on intervals of starvation also makesit possible to ignore the presence of prominent unconformities and to conclude (perhaps incorrectly) that sedimentary cyclicity is due primarily to variations in sediment supply (Galloway 1989), when the very existence of subaerial unconformities probably requires some additional mechanism (Christie-Blick 1991). The sequence stratigraphic approach can Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 456 CHRISTIE-BLICK& DRISCOLL also be problematic: The boundaries of depositional sequences tend to be of variable character, subject to modificationduring transgression, and difficult to recognize once they pass laterally into fully marinesuccessions. Yet sequence stratigraphy is preferable to genetic stratigraphy becausein manysettings sequence boundariesrelated to subaerial erosion are the primary stratigraphic discontinuities and therefore the key to stratigraphic interpretation (Figure 1B; Posamentier & James 1993). Allostratigraphy differs from sequencestratigraphy and genetic stratigraphy by taking a more descriptive approach to physical stratigraphy (NACSN 1983, Salvador 1987, Walker 1990, Blum1993, Mutti et al 1994). As formalized in the North AmericanStratigraphic Code, allostratigraphic units are defined and identified on the basis of boundingdiscontinuities; in this respect they are fundamentallysimilar to those of sequencestratigraphy (Figure 1). Different terminology is justified by Walker(1990) on at least two counts. Sequence stratigraphic concepts are regarded as imprecise, especially with respect to scale and the meaningof such expressions as "relatively conformable" and "genetically related." It is also arguedthat sequencestratigraphy is not universally applicable--for example, in unifacial or nonmarinesuccessions or where uncertainty exists about the origin of a particular surface. Allostratigraphic nomenclature is, however,rejected here for several reasons, including historical priority. The designations of "alloformations," "allomembers,"etc are unnecessary and overly formalistic; and these terms are not strictly applicable wherea boundingunconformitypasses laterally into a conformity (Baum& Vail 1988) or whereobjective evidence for a discontinuity is lacking (basinwardof points labeled Yin Figure 1). Aswith sequencestratigraphy, allostratigraphy involves makingjudgmentsabout the relative importanceof discontinuities (and hence the degree of conformabilityor genetic relatedness), but it does not require an attemptto distinguish surfaces of different origin. Nordoes this nongeneticterminologyhelp muchwheresequence stratigraphic interpretation is admittedly difficult (for example,in deposits lacking laterally traceable discontinuities). DEPARTURES FROM THE STANDARD MODEL In the standard modelfor sequence stratigraphy (Figure 2), unconformityboundedsequences are composedof"parasequences" and "parasequence sets," whichare stratigraphic units characterized by overall upward-shoalingof depositional facies and boundedby marineflooding surfaces and their correlative surfaces (Vail 1987; Van Wagoneret al 1988, 1990). These depositional elements are themselves assembled into "systems tracts" (Brown&Fisher 1977) according to position within a sequenceand the mannerin whichparasequences or parasequence sets are arranged or stacked (Posamentier et al 1988, Van Wagoneret al 1988). Boundingunconformities are classified as type 1 or type 2 accordingto such criteria as the presenceor absenceof incised valleys, the Annual Reviews www.annualreviews.org/aronline 457 Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCE STRATIGRAPHY prominence of associated facies discontinuities, and whether or not lowstand deposits (LST in Figure 2) are present in the adjacent basin. This particular view of stratigraphy is best suited to the study of siliciclastic sedimentation at a differentially subsiding passive continental margin with a well-defined shelf-slope break, and under conditions of fluctuating sea level. As with any sedimentary model, it represents a distillation of case studies and inductive reasoning, and modifications are therefore needed for individual examples, for other depositional settings, and as concepts evolve (Posamentier & James 1993). Parasequences Upward-shoalingsuccessions boundedby flooding surfaces (parasequences) are best developedin nearshoreand shallow-marine settings in both siliciclastic A I <SMST Ill EXPLANATION Fluvial andCoastalPlain ShorefaceandDeltaic Shelf andSlope Submarine"Fan" sb2 Intervalof Sediment Starvation (Maximum Flooding) Maximum a iv SubaerialHiatus ~~STbff _~,; ...... :~ ’" : ........ , . ¯ -DISTANCE Figure2 Conceptualcross sections in relation to depth (A) and geological time (B) showingstratal geometry,the distribution of silieielastie facies, and standard nomenclaturefor unconformityboundeddepositional sequences in a basin with a shelf-slope break (nmdified from Vail 1987 and Vail et ai 1991, specifically to include offlap). Systemstracts: SMST,shelf margin; HST, Itighstand; TST, transgressive; LST,[owstand. Sequenceboundaries: sb2, type 2; sbl, type 1. Other abbreviations: iss, interval of sedimentstarvation (condenseds~ction and maximum flooding surface of Vail 1987); ts, transgressive surface (top lowstandsurface and top shelf-marginsurface of Vail et al 1991);iv, incised valley; lsw, lowstandprogadingwedge;sf, slope fma; bff, basinfloor fan. Notethat in the seismic stratigraphie literature, the term submarine"fan" includes a range of turbidite systemsand sediment-gravity-flewdeposits that are not necessarily fan-shaped. Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 458 CHRISTIE-BLICK & DRISCOLL and carbonaterocks (James1984;VanWagoner et al 1988,1990;Swift et al 1991;Pratt et al 1992),andtheir recognitionis undoubtedly usefulin sequence stratigraphic analysis. However, the tendencyfor pigeonholingin sequence stratigraphytends to obscurerather than to illuminatethe rangeof facies arrangementsand processes involved. Sedimentarycycles vary from markedly asymmetricalto essentially symmetrical,with the degree of asymmetry decreasingin an offshoredirection anddepending also on whetherparasequences are arrangedin a foresteppingmotif (whichfavors asymmetry) or a backstepping one. (Thetermforesteppingmeansthat each parasequence in a succession representsshallower-water conditionsoverall than the parasequence beneathit. Backsteppingrefers to the opposite motif: overall deepeningupward.)Althoughnot strictly includedin the definitionof the termparasequence, similar sedimentarycycles with the samespectrumof asymmetry are observedin many lacustrine successions(Eugster& Hardie1975;Steel et al 1977;Olsen1986, 1990). Moreover,shoalingupwardsis not the only expressionof depositional cyclicity(for example, in alluvial andtidal depositsanddeep-marine turbidites). Objectiverecognitionof a parasequence, as opposedto someother depositional elementwith sharpboundaries,is thereforetenuousin nonmarine andoffshore marinesettings unless bounding surfacescan be shownto correlate withmarine floodingsurfaces. Theconceptof parasequences andparasequence sets as the buildingblocksof depositionalsequences is also largelya matterof convention rather thana statementabouthowsedimentsaccumulate at different scales. Thereis clear overlap in the lengthscales andtimescales representedby parasequences andhigh-order sequences (VanWagoneret al 1990, 1991; Kerans & Nance1991; Mitchum & VanWagoner1991; Vail et al 1991; Posamentier & Chamberlain1993; Posamentier& James1993; Sonnenfeld& Cross 1993; Christie-Blick et al 1995). The distinction betweensequencesand parasequencesis therefore primarilya function of whether,at a particular scale of cyclicity, sequence boundariescan or cannotbe objectivelyidentified andmapped. Anunfortunate by-productof the quest for sequencesand sequenceboundariesis to impose sequence nomenclaturewhenparasequenceterminologywouldbe moreappropriate. Floodingsurfacesare sometimes interpreted as sequenceboundaries whenno objective evidencefor such a boundaryexists (e.g. Lindsay1987, Prave1991,Lindsayet al 1993,Montafiez& Osleger1993)or, if a sequence boundary is present,it is locatedat a lowerstratigraphiclevel. Systems Tracts Thethreefoldsubdivisionof sequences into systemstracts is basedon the phase lag between transgressive-regressive cycles andthe development of corresponding sequenceboundaries(Figure2B). In the standardmodelfor siliciclastic sedimentation with a shelf-slopebreak, regressionof the shorelinecontinues Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCESTRATIGRAPHY 459 after the developmentof the sequenceboundary,so that the regressive part of any cycle of sedimentationis divisible into two systems tracts: the highstand belowthe boundary(HSTin Figure 2) and the lowstand(or shelf margin) tems tract above it (LSTand SMST in Figure 2). The designation of systems tracts has becomestandardprocedurein sequencestratigraphy as if this werean end in itself but, as with parasequences,subjective interpretation and pigeonholing tend to obscurethe natural variability in sedimentarysystems. There is no requirementfor individual systems tracts to have any particular thickness or geometry,or evento be representedon a particular profile or in a particular part of a basin (Posamentier & James1993). It is commonin deep water for lowstandunits to be stacked, with intervening transgressive and highstandunits representedby relatively thin intervals of sedimentstarvation. In shelf areas, the stratigraphy tends to be composed primarily of alternating transgressive and highstandunits, but these vary greatly in thickness and they are not necessarily easy to distinguish. Still farther landward,highstandsmaybe stacked with no other systemstracts intervening, a situation that is likely to challenge those intent on assigning systems tract nomenclaturein nonmarinesuccessions. The most troublesom, e systems tract is the lowstand, which according to the original definition of the term represents sedimentationabovea sequence boundaryprior to the onset of renewedregional transgression (Figure 2). is characterized by remarkablyvaried facies and in manycases by a complex internal stratigraphy that in deep-marineexamplescontinuesto be the subject of vigorous debate (Weimer1989, Normarket al 1993). The lowstandis also the one element of a depositional sequencethat separates it from a transgressiveregressive cycle (e.g. Johnsonet a11985,Embry1988),It is perhapsnatural that sequencestratigraphers have attemptedto identify lowstandunits, even where the presence of such deposits is doubtful (for example, manyshelf and ramp settings), becausethis helpsto deflect the criticism that sequencestratigraphyoffers nothing morethan newterminologyfor long-established concepts. In shelf and rampsettings, the term lowstandis routinely applied to any coarse-grained and/or nonmarinedeposit directly overlying a sequence boundary, especially wheresuch deposits are restricted to an incised valley (e.g. Baum&Vail 1988, VanWagoneret al 1991, Southgate et al 1993). However,sedimentological and paleontological evidencefor estuarine sedimentationwithin (fluvially incised) valleys (e.g. Hettinger et al 1993)in manycases precludesthe lowstandinterpretation, because such estuaries develop as a consequenceof transgression. JC Van Wagoner(personal communication,1991) has defended the use of the term lowstandfor estuarine valley fills on the groundsthat the differentiation of sandstones within incised valleys from those of the underlying highstand systemstract is of practical importancefor the delineation of reservoirs for oil and gas. However,such commercialobjectives can surely be achieved without fundamentallyaltering the systemstract concept. Annual Reviews www.annualreviews.org/aronline 460 CHRISTIE-BLICK& DRISCOLL Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. Variations in SequenceArchitecture Case studies in a great variety of settings have led to attempts to develop modified versions of the standard sequencestratigraphic model. Examplesinclude settings wheresedimentationis accompaniedby growthfaulting, terraced shelves and siliciclastic ramps, carbonateplatforms and ramps,nonmarineenvironments(fluvial, eolian, and lacustrine), and environmentsproximalto large ice sheets (Vail 1987; Sarg 1988; Van Wagoneret al 1988, 1990; Boulton 1990; Olsen 1990; Vail et al 1991; Greenlee et al 1992; Posamentier et al 1992a; Walker &Plint 1992; Dam& Surlyk 1993; Handford & Loucks 1993; Kocurek & Havholm1993; Schlager et al 1994; Shanley & McCabe1994). Attempts have also been madeto integrate geological studies in outcrop and the subsurface with seismic profiling and shallow sampling of modernshelves and estuaries (Demarest & Kraft 1987; Suter et al 1987; Boyd et al 1989; Tessonet al 1990, 1993; Allen &Posamentier 1993, Chiocci 1994), flume experiments(Woodet al 1993, Kosset al 1994) and small-scale natural analogues (Posamentier et al 1992b), and computersimulations (Jervey 1988, HellandHansenet al 1988, Lawrenceet al 1990, Ross 1990, Reynolds et al 1991, Steckler et al 1993, Bosenceet al 1994, Ross et al 1994). The main emphasis of these studies has been to documentvariations in the arrangementof facies and associated stratal geometry,but amongthe moreinteresting results has been the emergenceof somenewideas about the origin of sequence boundaries and other stratigraphic discontinuities. ORIGIN OF SEQUENCEBOUNDARIES The conventional interpretation of sequenceboundariesis that they are due to a relative fall of sea level (Posamentieret al 1988, Posamentier&Vail 1988, Sarg 1988, Vail et al 1991). For example,a boundarymight be said to develop whenthe rate of relative sea-level fall is a maximum or whenrelative sea level begins to fall at somespecified break in slope, thereby initiating the incision of valleys by headwarderosion. The concept of relative sea-level change accounts qualitatively for the roles of both subsidenceand eustasy in controlling the space available for sediments to accumulate.However,existing modelsare fundamentallyeustatic because it is invariably the eustatic componentthat is inferred to fluctuate; the rate of subsidenceis assumedto vary only slowly, if at all. Here wedrawattention to several waysin whichthe conventionalexplanation of sequenceboundariesneeds to be modified, particularly in tectonically active basins. Gradual vs Instantaneous Developmentof Sequence Boundaries It is widely assumedthat sequence boundaries develop more or less instantaneously(Posamentieret al 1988, Vail et al 1991). Themainevidencefor this Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCESTRATIGRAPHY 461 the markedasymmetryof depositional sequences, which in seismic reflection profiles are characterized by progressive onlap at the base and by a downward (or basinward)shift in onlapat the top (Figure 2; Vail etal 1977, 1984;Haqet 1987). (Theterm onlap refers to the lateral terminationof strata against an underlying surface.) Abruptdownward shifts in onlap are taken to imply rates of relative sea-level changesignificantly higher than typical rates of subsidence, and that the sea-level change must therefore be due to eustasy, presumably glacial-eustasy (Vail et al 1991). Whileit is undoubtedlytrue that glacial-eustasy has played an important role in modUlatingpatterns of sedimentationsince Oligocenetime (Bartek et al 1991, Miller et al 1991), and probably during other glacial intervals in earth history, such explanationsare not plausible for periods such as the Cretaceous for whichthere is very little evidencefor glaciation (Frakes et al 1992). Nor are such explanatioiis required by available stratigraphic data. In manycases, the highstand systemstract is divisible into twoparts: a lower/landwardpart characterized by onlap and sigmoidclinoforms(clinoforms are inclined stratal surfaces associated with progradation), and an upper/seawardpart characterized by offlap and oblique clinoforms (Figure 2; Christie-Blick 1991). Offlap (the upwardterminationof strata against an overlying surface) is not likely be due solely to the erosional truncation of originally sigmoidclinoforms, The progressive onlap implied by this interpretation is not possible during a time of increasingly rapid progradation without a markedincrease in the sediment supply. Moreover,the inferred erosion is unlikely to havetaken place in the subaerial environmentbecausesubaerial erosion tends to be focused within incised valleys, and the amountof erosion required in manycases exceeds what can reasonably be attributed to shoreface ravinementduring transgression. A more reasonable interpretation is that offlap is due fundamentallyto bypassingduring progradation (toplap of Mitchum1977), implyingthat sequenceboundaries developgradually over a finite interval of geologic time (Christie-Blick 1991). Supportfor this idea is providedby recent high-resolution sequencestratigraphic studies in outcrop. A remarkable series of forestepping high-order sequences is exposedin the upper part of the San Andres Formation, a carbonate platform of Permian age in the GuadalupeMountainsof southeastern NewMexico (Figure 3A; Sonnenfeld & Cross 1993). Individual high-order sequencesconsist of two half-cycles. Thelowerhalf-cycle (primarily transgressive) is predominantlysiliciclastic and onlaps the underlying sequenceboundary. The upper half-cycle (regressive) is composedmainly of carbonate rocks and is characterized by onlap and downlap(downward termination of strata) the base and in someinstances by offlap at the top. Thesehigh-order sequences are themselves oblique to a prominentlow-order sequenceboundaryat the top of the San AndresFormation (top of sequences uSA4and uSA5). On the basis of karstification, this surface is interpreted by Sonnenfeld&Cross (1993) Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 462 CHRISTIE-BLICK& DRISCOLL have been exposedsubaerially. At the resolution of conventional seismic data, only the low-order sequence boundaries in the San Andres Formation would be identified (Figure 3B) and the oblique truncation of high-order sequences wouldbe interpreted as offlap (cf figure 11 of Brinket al 1993). However,the siliciclastic half-cycles of the high-ordersequencesindicate that the platform was bypassed episodically during overall progradation. The sequence boundary at the top of the San Andreswas therefore not producedby an instantaneous downward shift in onlap but is instead a compositesurface. Anotherpertinent exampleof high-resolution sequencestratigraphy is drawn from the work of Van Wagonerand colleagues in a late Cretaceous forelandbasin ramp setting in the BookCliffs of eastern Utah and western Colorado (Van Wagoneret al 1990, 1991). Numeroussequence boundaries have been documentedin the strongly progradational succession betweenthe Star Point Formation and Castlegate Sandstone (Figure 4A). Twoof the most prominent boundaries are present at the level of the Desert Memberof the Blackhawk Formationand Castlegate Sandstone (Figure 5). Theseboundaries are characterized by valleys as muchas several tens of meters deepincised into underlying A ~ SA4/5 EXPLANATION ~ ....... ~ 300m Sequence Boundary High-OrderSequenceBoundary Other Stratal Surfaces Stratal Termination SedimentDepositedAbove ~ Storm WaveBase Sediment Deposited [~ Storm Wave Base B Approx. Location of Detail ~ _,, ,~,~ o e Sa des 100 Below 1 m ..... 5 km ==,,, ~---------Cutoff~~ uSA3 Grayburg ne;o~n ~ Brushy ~Canyon Figure3 (A) Simplified stratigraphiccrosssectionof the upperpart of SanAndres Formation (Permian) in the Guadalupe Mountains, New Mexico. (B)Schematic representation of the broader stratigraphic contextof theSanAndres Formation at the scaleof conventional seismicreflection data. Individualhigh-ordersequences withinsequences uSA4(numbered 1-12)anduSA5 (numbered13-14)are characterized bystratal onlapandofflapandare themselves obliqueto a still lower-order sequenceboundary at the top of the SanAndresFormation. Thedatumfor cross sectionAis the baseof the Hayes sandstone oftbeGrayburg Formation. Alsoshown in Bare the names of otherassociated lithostratigraphic units. (Modified fromSonnenfeld &Cross1993.) Annual Reviews www.annualreviews.org/aronline SEQUENCE STRATIGRAPHY 463 A Thistle Price ~1 ~ Sunnyside GreenRiver I I I ~/~.NorthHorn(Part) .......... Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. ~ BTurkeyCreek S Palisade L ~///~T~$dl~r, 1 FarroW’, ~l~sien ~~’~ ~ ........ ~xX~~--~ &~~~esed oe ~ ..~o ~~ ~~ and UtahI Colo. ,, _ ~_. Mbr Blac~awk ~ Op~ Marine ~ ~asp ~ Forelapd- ~ Ll~oral Deltal 50 km Fort Collins Mowry Shale (~ Skull Creek........... ......... Plalnview,~ :’ ......... ’ " CastlegateSandstone o~ ~ Fm. . Shelf ................... ~ LowerCoastalPlain andIncisedValley Fill UpperCoastalPlain ~ Piedmont ~ ~ Mostly Nonmarine ~ ...... -- Sequence Boundary Max. Flooding Surface Other Stratal Surface Figure4 Simplifiedstratigraphiccross section andlithostratigraphic nomenclature for mid-to upperCretaceousstrata in the BookCliffs, eastern UtahandwesternColorado(A; fromNummedal &Remy 1989),witha detail of the Albiansequencestratigraphy(DakotaGroup)of noah-central Colorado(B; fromWeimer 1984and RJ Weimer,personal communication, 1988). A detail of the DesertMember of the Blackhawk FormationandCastlegate Sandstone(box in A) is illustrated in Figure5. Thebaseof the foreland-basinsuccessionis markedapproximately by a regional sequenceboundary ai or near the base of the DakotaSandstone(in A) andat or near the base the Muddy (or J) Sandstoneof the DakotaGroup(in B). FCrefers to the Fort Collins Member, portionof the Muddy Sandstone that locally underliesthe sequenceboundary. littoral sandstones,by the offlap of successiveparasequences, andby a marked basinwardshift of facies. In the conventionalinterpretation, the incision of valleys by headward erosion from a break in slope near the shoreline ought to deliver a significant volume of sediment tothe adjacent shelf, and prominent lowstand sandstones would be expected (Van Wagoner et al 1988, 1990). Instead, each sequence boundary passes laterally into a marine flooding surface and eventually into the MancosShale (Figure 4A) with little or no evidence for lowstand deposits as this term is defined above.1 Our solution to this apparent paradox is that the valleys were not incised as a result of headward erosion. ID Nummedal (personal communication, 1994)has recently identified a possible lowstand depositbasinward of the Castlegatelowstandshorelineonthe basis of well-loginterpretation.The depositis perhapsanalogous to the relativelythin lowstandunits fromthe Albertabasindescribed byPlint (1988,1991)andPosamentier et al (1992a). Annual Reviews www.annualreviews.org/aronline 464 CHRISTIE-BLICK & DRISCOLL Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. A consequence of the idea that sequence boundaries develop gradually during highstand progradation is that incised valleys at the Desert and Castlegate sequence boundaries initially propagated downstream, and that most of the eroded sediment accumulated at the highstand shorelines. If sequence boundaries do not after all develop instantaneously, it is not necessary to call upon rapid eustatic change for which there is no plausible mechanism during nonglacial times. Forward modeling indicates that sequence West Thompson ’ Thompson Pass Canyon Tusher Canyon W Sagers Canyon East Bull Canyon Strychnine Wash Flooding Surface at baseof Buck Tongue SF/E Castlegate Sequence OT OT SequenceBoundary PassesLaterally into FloodingSurface LSF OT 20 m OT f 10 \ ~ ~-~ DesertSequence Boundary o ~ ~ W m Marine Shale Littoral Sandstone Shale Coal EXPLANATION ...... Max.~:loodlng Surface OtherStratal Surface Para,llel Lamination Current Ripples ~ Estuarine~--Cross-stratification Sandstone ~ conglomerate ~ cross.stratification Figure 5 Stratigraphic cross section of the Desert Member of the Blackhawk Formationand Castlegate Sandstoneshowingdepositional facies andsequencegeometry(simplified fromVan Wagoneret al 199l, Nummedal &Cole 1994). See Figure 4 for location. The two sequence boundariesillustrated are characterizedup-dip (west)by well-developed incisedvalleys.TheDesert sequenceboundary passesdown-dip (eastward)in the vicinity of SagersCanyon into a marineflooding surfacethat wasprobablymodifiedby ravinement duringtransgression.Asimilartransition is observedin the CastlegateSandstone as it is tracedfarther eastward.Notethe presenceof offlappingparasequences beneatheachsequenceboundary.Abbreviationsfor generalizedpaleoenvironmerits:BF,braidedfluvial; SF/E,sinuousfluvial/estuarine;FS, foreshore;USF,uppershoreface; LSF,lowershoreface;OT,offshoretransition. Systems tracts (modifiedfromthe interpretationsof VanWagoner et al 1991and Nummedal &Cole 1994): HST,highstand; TST,transgressive. Some uncertaintyexists aboutthe locationof the interval of maximum floodingin the Desertsequence owing to the difficultyof interpretingparasequence stackingtrendsin thin sections:It is at or slightly abovethe dashedline labeled RavinementSurface(D Nummedal, personal communication, 1994). Annual Reviews www.annualreviews.org/aronline SEQUENCESTRATIGRAPHY 465 Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. boundaries can be produced by eustatic fluctuations at rates comparableto typical rates of tectonic subsidenceand that they do so by gradual basinward expansionand subsequentburial of zones of bypassingand/or erosion (ChristieBlick 1991, Steckler et al 1993). Consequently,if the rate of eustatic change required to generate a sequenceboundaryis small, there is no reason to assume that sequenceboundariesare necessarily due to eustatic change. Tectonically Active Basins In the light of these considerations, howdo sequence boundaries develop in tectonically active settings such as extensional,foreland, and strike-slip basins? Oneview, whichis almost certainly incorrect, is that the local developmentof sequenceboundariesin such basins maybe entirely tectonic in origin (Underhill 1991). Anotherview is that tectonic processes control long-term patterns of subsidenceand that short-term depositional cyclicity is due to eustatic change (e.g. Vail et al 1991, Devlin et al 1993, Lindsayet al 1993). Again, this an assumptionthat in manycases is probably not warrantedfor times in earth history whenrates of eustatic change were comparableto rates of tectonic subsidence (e.g. Cretaceous). Sequenceboundaries are not merelyenhanced obscuredby tectonic activity (cf Vail et al 1984, 1991). Boththeir timing and their very existence are due to the combinedeffects of eustasy and variations in patterns of subsidence/uplift and sedimentsupply. The roles of these factors and the mannerin whichthey interact are admittedlyvery difficult to sort out, but recent studies provide someuseful first-order clues. Animportantattribute of tectonically active basinsis that it is possiblefor the rate of tectonic subsidenceto increase and decrease simultaneouslyin different parts of the samebasin (Figure 6). Sequenceboundariesthat are fundamentally of tectonic rather than eustatic origin cannotthereforebe attributed satisfactorily to the conceptof a relative sea-levelfall or evenan increasein the rate of relative sea-level fall, becauserelative sea-level mayhavebeenboth rising and falling at an increasingrate in different places. In this regard, patterns of subsidenceand uplift in foreland and extensional basins are actually very similar during times of active deformationas well as quiescence(Christie-Blick &Driscoll 1994). In the case of a foreland basin, loading by the adjacent orogenleads to regional subsidenceand to uplift in the vicinity of the peripheral bulge, with a wavelengthand amplitudethat are governedby the flexural rigidity of the lithosphere (Figure 6A; Beaumont 1981, Karner &Watts 1983). Uplift mayalso occur locally at the proximal margin of the basin as a result of the propagationof thrust faults at depth. Similarly,in extensional basins, subsidenceand tilting of the hanging-wallblock (abovethe fault in Figure 6) are accompaniedby uplift of the footwall (belowthe fault; Wernicke &Axen 1988, Weissel & Karner 1989). During times of tectonic quiescence, these patterns are reversed, although the amplitudesare small in Annual Reviews www.annualreviews.org/aronline 466 CHRISTIE-BLICK& DRISCOLL A ACTIVE DEFORMATION Foreland basin j ~ ~ B QUIESCENCE Foreland basin PeripheralBulge Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. Thrusting Extensional basin NormalFaulting ~ Footwall Extensionalbasin EXPLANATION Hanging Wall [~ Sediment Thermal Subsidence NNNNWater Figure 6 Schematicdiagrams comparingpatterns of uplift and subsidence in foreland and extensional basins during times of active deformation(A) and quiescence(B). See text for discussion. comparisonwith the deflections engenderedby active deformation(Figure 6B; Heller et al 1988, Jordan & Flemings 1991). Erosional unloading leads to regional rebound of the orogen and adjacent depocenter and to depression of the peripheral bulge. At the same time, the accumulationof terrigenous sedimentderived fromthe orogenresults in additional subsidenceat the distal side of the basin and to lateral migrationof the peripheral bulge awayfrom the orogen (Jordan &Flemings1991). A similar pattern of uplift and subsidence mayarise during times of tectonic quiescencein extensional basins, through a combinationof erosional unloadingof the footwall block and thermally driven subsidence,especially whenthe latter is offset fromthe original depocenter(as illustrated in Figure,6B). Morecomplicated scenarios can also be envisaged. For example, foreland basins are commonlysegmentedby block-faulting, and lithospheric extension maybe accommodated by a series of tilted fault blocks or distributed inhomogeneously as a function of depth and lateral position within the lithosphere. Subsidenceand uplift mayalso be complicatedin three dimensionsby the presence of salients in the orogenor of accommodation zones in extensional basins. Patterns of subsidenceand uplift in strike-slip basins tend to be evenmorecomplicated and subject to markedchanges on short time scales (Christie-Blick Biddle 1985). The developmentand characteristics of sequenceboundaries in tectonically active basins are directly related to patterns of subsidenceand uplift of the sort outlined here and to the fact that the patterns vary betweentimes of active deformation and quiescence. At a regional scale, the progradation of Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCESTRATIGRAPHY 467 sedimentary systems, the filling of available accommodation with sediment, the loweringof depositional base level, and the incision of valleys are favored duringtimes of tectonic quiescence(e.g. Heller et al 1988).In contrast, active deformationis associated with regional subsidence and tilting, flooding and backsteppingof sedimentarysystems, an increase in topographicrelief along the faulted basin margins, and a narrowingof the depocenter(e.g. Underhill 1991). In both foreland and extensional basins, the most prominentsequence boundariestherefore are expected to correspondwith the onset of deformation. Theseboundariesconsist of subaerial exposuresurfaces that pass laterally into marine onlap/downlapsurfaces of regional extent (Jordan &Flemings 1991, Underhill 1991, Driscoll 1992, Christie-Blick &Driscoll 1994, Driscoll et al 1995). In contrast to the standard model, the formationof a sequenceboundary is not necessarily associatedwith a basinwardshift in facies, and wherepresent, such facies shifts maybe restricted to areas that weresubaerially exposed.The developmentof topographic relief mayin somecases lead to the accumulation of thick successions of turbidites in deep water. However,contrary to the conventionalinterpretation, these deposits are not strictly "lowstands"if they accumulateduring a time of regional flooding [see Southgate et al (1993) and Holmes&Christie-Blick (1993) for a possible examplefrom the Devonian the Canningbasin, Australia]. Several of these points can be illustrated with reference to the late Cretaceous foreland basin of Utah and Colorado (Figure 4). The base of the foreland-basin succession in eastern Utah and Coloradocorresponds approximately with a regional sequence boundaryat or near the base of the Dakota Sandstone(Figure 4A) and at or near the base of the Muddy(or J) Sandstone of the DakotaGroup(Figure 4B). The succession abovethis surface is characterized by a markedincrease in the rate of sediment accumulationand by an abrupt transition from nonmarineto relatively deep marinesedimentaryrocks (Mancos/Mowry Shale; Heller et al 1986, Vail et al 1991). These features are fundamentallyattributable to the onset in late Albiantime of a phaseof crustal deformationand accelerated subsidence; the contribution of eustatic change is indeterminate but is presumedto have been small. Wedo not preclude the possibility of slightly earlier (late Aptianto Albian, pre-Dakota)foreland-basin developmentto the west (Yingling &Heller 1992), but the strata are entirely nonmarineand the evidence is equivocal. Within the foreland-basin succession, the origin of other sequenceboundariesis less firmly established, but the BlackhawkFormation and Castlegate Sandstoneexhibit features that are consistent with our model. The Blackhawkand lower/distal part of the Castlegate (belowthe Castlegate sequence boundary; Figure 5) are characterized strong progradation and the developmentof offlap, consistent with erosional unloading of the orogenduring a time of tectonic quiescence (cf Posamentier & Allen 1993). The upper/proximalpart of the Castlegate (above the sequence Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 468 CHRISTIE-BLICK& DRISCOLL boundary)is transgressive and, as datumedfroma floodingsurface at the base of the BuckTongueof the MancosShale, it thickens towardsthe orogen(Figure 5). At a regional scale, it appears to pass laterally into syn-orogenicconglomerate (Price River Formation) and to overstep the BlackhawkFormation, which was uplifted and bevelled to the west (Figure 4). Thesefeatures makeit hard to argue that the Castlegate sequence boundarydevelopedsolely or even primarily as a result of eustatic change. A seismic exampleof sequence developmentrelated to episodic block faulting in an extensional setting is providedby a seismic reflection profile (line NF-79-108)from the Jeanne d’Arc basin of offshore eastern Canada(Figure 7). The basin records a series of extensional events betweenlate Triassic and early Cretaceous time (Jansa &Wade1975, Tankard et al 1989, McAlpine1991); Figure 7 illustrates the last of these prior to the onset in late Aptiantime of seafloor spreading betweenthe GrandBanks of Newfoundlandand the Iberian peninsula. Reflections below the late Barremian unconformity are approximately parallel and concordantwith the unconformity.Abovethis surface, the onlap of reflections and their divergencetowards the border fault documentthe onset of crustal extension. Similar reflection geometryis evident at the early Aptian and late Aptian unconformities, although reflections are approximately parallel abovethe latter. This is taken to indicate that extensionhad ceased by late Aptian time (Driscoll 1992, Driscoll et al 1995). Evidencefromavailable core indicates that the onlap surfaces are associated with upwarddeepening of depositional facies, but the surfaces are interpreted as sequenceboundaries becausethey are inferred to pass laterally into subaerial exposuresurfaces. The observedgeometryrequires rifting betweenlate Barremianand late Aptiantime. Our preferred interpretation is that each of the mappedsequence boundaries records times of accelerated block tilting. Analternative interpretation, that the early and late Aptian boundariesare due primarily to eustatic fluctuations duringa time of moreor less continuousblocktilting, is not consistelat with the absence of anticipated lowstanddeposits in closed paleobathymetriclows (for example,at the MercuryK-76 well, Figure 7). Role of In-Plane Force Variations Sequence Boundaries in the Origin of High-Order Oneof the mainargumentsfor interpreting high-order depositional sequences in terms of eustatic changeis the absence of another suitable mechanism.We have seen in the Jeanne d’Arc basin examplethat episodic tilting mayprovide such a mechanism in extensional basins. However,difficulties arise in foreland basins because,in such settings, subsidenceis driven primarily by the integrated vertical load of the orogen. This can changeonly slowly through a combination of internal deformation,the propagationof thrust faults into the syn-orogenic sediments, and the erosion of topography(Sinclair et al 1991). Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCESTRATIGRAPHY 469 An imaginative and somewhatcontroversial solution to this dilemmahas emergedfrom the recognition and modelingof in-plane force variations in the lithosphere (Lambeck1983, Cloetingh et al 1985, Karner 1986, Braun &Beaumont1989, Karner et al 1993). The best evidence for the existence of such forces is the incidence of intraplate earthquakes (e.g. Lambeck et al 1984, Bergman&Solomon1985). Changes in in-plane force are thought to result from changesin the plate-boundaryforces associated with, for example, ridge-push, slab-pull, and collisional tectonics (Sykes &Sbar 1973, Cloetingh &Wortel 1985, Zobacket al 1989). Althoughuncertainty exists about both the magnitudeof the forces and the time scale over which they might vary, it is not unreasonable to think that such forces maybe relevant to the developmentof somesequence boundaries. The response of the lithosphere to in-plane compressionconsists of two components,one elastic (flexural) and the other inelastic (brittle; Goetze &Evans 1979, Karner et al 1993). The brittle component,whichis associated with deformationin the upper part of the lithosphere, is influenced by the preexisting structure of the crust and the orientation of faults with respect to the applied tectonic force. It includes the well-knownphenomenon of extensional basin inversion. The flexural response to in-plane compressiondependson the shape of any preexisting deflection of the lithosphere, the amplitudeof the applied force, and the flexural strength of the lithosphere at the time the force wasapplied. In the case of foreland basins, the predicted flexural response to compressionconsists of enhancedsubsidence in the depocenter,uplift of the peripheral bulge, and a reductionin the flexural wavelength. The amplitude of subsidence and uplift producedin this wayare approximatelythe same because the wavelengthsof features being selectively modified are approximatelyequal (Karner et al 1993). The predicted flexural responsefor extensional basins is quite different. In-plane compressionresults in uplift of the depocenterand increased subsidenceof the basin margins. Inplane tension leads to uplift of the basin marginsand to enhancedsubsidenceof the depocenter (Braun & Beaumont1989, Karner et al 1993). The amplitude and wavelengthof the flexural deformationare a strong function of the extensional basin geometryand, in the case of basins undergoingpost-rift thermal subsidence, of the spatial relationship betweenrift basins and any associated passive continental margin. In view of these considerations, our concepts of active deformation and tectonic quiescence need to be modified. With respect to this second-order effect, panels that in Figure 6 are labeled "active deformation"include times of increased in-plane compressionin the foreland basin exampleand decreased in-plane compression(increased tension) in the extensional basin example. Owingto the relatively short length scales relevant to extensional basins (tens of kilometers), it is anticipated that the stratigraphy of such basins oughtto be influencedstronglyevenat short timescales by episodicblock tilting (the brittle Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. CHRISTIE-BLICK & DRISCOLL Annual Reviews www.annualreviews.org/aronline 470 E m 0 u- ? W Y h b IL z aJ .-C -I Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. Annual Reviews www.annualreviews.org/aronline : Ill/I II SEQUENCE STRATIGRAPHY 471 Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 472 CHRISTIE-BLICK& DRISCOLL componentof the deformation). In contrast, because the integrated vertical load of an orogen changesonly slowly (millions to tens of millions of years; Sinclair et al 1991), the stratigraphy of foreland basins oughtto be muchmore sensitive on short time scales to the flexural effects of changesin in-plane compression, providing that the forces involvedare sufficiently large. A possible test of this idea is to comparethe stratal geometryof sequencesof different scale in the samebasin. If high-order sequencesare due to eustatic change, as manyhave inferred (e.g. Posamentier &Allen 1993), their geometryought reflect overall patterns of subsidence.If they are instead a result of changesin in-plane compression,high-order transgressive systems tracts ought to thicken preferentially towardthe orogenrelative to associated highstandunits (as appears to be the case in the Castlegate example), and backstepping sequences ought to thicken toward the orogen relative to forestepping sequences. The complicationsassociated with lateral changesin facies, compaction,and water depth can be reduced by studying transects parallel to shorelines across foreland basins with axial drainage (for example, the DunveganFormation of the Alberta basin; Plint 1994). CONCLUSIONS Sequencestratigraphy is concernedwith the analysis of sedimentsand sedimentary rocks with reference to the mannerin whichthey accumulatelayer by layer. Asa practical techniqueand in spite of existing terminology,it requires no assumptionsabout eustasy. Oneof the principal frontiers of the discipline is an effort to developan understandingof the manyinterrelated factors that govern sedimenttransport and accumulationin a great range of depositional settings and environments. The conventional interpretation of sequence boundaries is that they are due to a relative fall of sea level and that they developmoreor less instantaneously. In this paper we argue that in manycases such boundaries form gradually over a finite interval of geologic time. The widely employed concept of relative sea-level change provides few insights into howsequence boundariesactually develop, especially in tectonically active basins. ACKNOWLEDGMENTS This paper is an outgrowth of more than a decade of research in sequence stratigraphy in a widevariety of depositional and tectonic settings. Weare indebted to numerouscolleagues for stimulating discussions of the issues, and we thank MSteckler and L Sohl for reviewing the manuscript. Weacknowledge support from the National Science Foundation (Earth Sciences and OceanSciences); Office of NavalResearch; the Donorsof the PetroleumResearch Fund, administered by the American Chemical Society; and the Arthur D Storke MemorialFund of the Departmentof Geological Sciences, ColumbiaUniversity. This paper is Lamont-Doherty Earth Observatory Contribution No. 5257. Annual Reviews www.annualreviews.org/aronline SEQUENCE STRATIGRAPHY 473 AnyAnnual.Review chapter,as well as anyarticle cited in an AnnualReviewchapter, maybe purchasedfromthe Annual ReviewsPreprintsandReprintsservice. 1-800-347.8007;415-259-5017;emaiharpr@class.org Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. Literature Cited Allen GP, Posamentier HW.1993. Sequence stratigraphy and facies modelof an incised valley fill: the GirondeEstuary, France. J. Sediment. Petrol. 63:378-91 Bartek LR, Vail PR, Anderson JB, EmmetPA, Wu S. 1991. Effect of Cenozoic ice sheet fluctuations in Antarcticaon the stratigraphic signature of the Neogene.J. Geophys.Res. 96:6753-78 BaumGR, Vail PR. 1988. Sequence stratigraphic concepts applied to Paleogene outcrops, Gulf and Atlantic basins. See Wilgus et al 1988, pp. 309-27 BeaumontC. 1981. Foreland basins. Geophys. J. R. Astron. Soc. 65:291-329 Bergman EA, Solomon SC. 1985. Earthquake source mechanismsfrom body-waveforminversion and intraplate tectonics in the northern Indian Ocean. Phys. Earth Plant. Inter. 4:1-23 Berg OR, Woolverton DG, eds. 1985. Seismic Stratigraphy H: An Integrated Approachto HydrocarbonExploration. Am. Assoc. Petrol Geol. Mem.39. 276 pp. BlumMD.1993. Genesis and architecture of incised valley fill sequences: a late Quaternary example from the Colorado River, Gulf coastal plain of Texas. See Weimer& Posamentier 1993, pp. 259-84 Bosence DWJ, Pomar L, Waltham DA, Lankester HG. 1994. Computer modeling a Micocene carbonate platform, Mallorca, Spain. Am.Assoc. Petrol. Geol. Bull. 78:24766 Boulton GS. 1990. Sedimentary and sea level changesduring glacial cycles and their control on glacimarine facies architecture. In Glacimarine Environments: Processes and Sediments, ed. JA Dowdeswell,JD Scourse, pp. 15-52. Geol. Soc. LondonSpec. Publ. 53. 423 pp. BowringSA, Grotzinger JP. 1992. Implications of newchronostratigraphyfor tectonic evolution of Wopmay orogen, northwest Canadian shield. Am. J. Sci. 292:1-20 BoydR, Suter J, PenlandS. 1989. Relation of sequence stratigraphy to modernsedimentary environments. Geology 17:926-29 Braun J, BeaumontC. 1989. A physical explanation of the relation betweenflank uplifts and the breakupunconformityat rifted continental margins. Geology 17:760-64 Brink GJ, KeenanHG, BrownLF Jr. 1993. Deposition of fourth-order, post-rift sequences and sequence sets, lower Cretaceous (lower Valanginianto lower Aptian), PletmosBasin, southern offshore, South Africa. See Weimer &Posamentier 1993, pp. 393-410 BrownLF Jr, Fisher WL.1977. Seismic stratigraphic interpretation of depositional systems: examplesfrom the Brazilian rift and pull-apart basins. See Payton1977, pp. 21348 Burton R, Kendall CGStC,Lerche I. 1987. Out of our depth: on the impossibility of fathomingeustasy from the stratigraphic record. Earth-Sci. Rev. 24:237-77 Cathles LM, Hallam A. 1991. Stress-induced changes in plate density, Vail sequences, epeirogeny, and short-lived global sea level fluctuations. Tectonics 10:659-71 ChiocciFL. 1994. Veryhigh-resolution seismics as a tool for sequence stratigraphy applied to outcrop scale---examples from eastern Tyrrhenian margin Holocene/Pleistocene deposits. Am.Assoc. Petrol. Geol. Bull. 78:37895 Christie-Blick N. 1990. Sequencestratigraphy and sea-level changesin Cretaceous time. In Cretaceous Resources, Events and Rhythms, ed. RNGinsburg, B Beaudoin, pp. 1-21. Dordrecht: Kluwer, NATO ASI Series C, 304. 352 pp. Christie-Blick N. 1991. Onlap, offlap, and the origin of unconformity-bounded depositional sequences. Mar. Geol. 97:35-56 Christie-Blick N, Biddle KT, eds. 1985. StrikeSlip Deformation,Basin Formation, and Sedimentation. Soc. Econ. Paleontol. Mineral. Spec. Publ. No. 37. 386 pp. Christie-Blick N, Driscoll, NW.1994. Relative sea-level change and the origin of sequence boundariesin tectonically active settings. Am. Assoc. Petrol. Geol. Annu.Conv., Denver,Abstr. 121 Ctu’istie-Blick N, DysonIA, von der Borch CC. 1995. Sequencestratigraphy and the interpretation of NeoproterozoicEarth history. In Terminal Proterozoic Stratigraphy and Earth History, ed. AHKnoll, MRWalter. Precambrian Res. (Special issue). In press Christie-Blick N, Grotzinger JP, yon der Botch CC. 1988. Sequencestratigraphy in Proterozoic successions. Geology16:100-4 Christie-Blick N, Mountain GS, Miller KG. 1990. Seismic stratigraphic record of sealevel change. In Sea-Level Change,pp. 116140. Natl. Acad. Sci. Stud. Geophys.234pp. CloetinghS. 1988.Intraplate stresses: a newelement in basin analysis. In NewPerspectives in Basin Analysis (Pettijohn Volume),ed. Kleinspehn, C Paola, pp. 205-23. NewYork: Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 474 CHRISTIE-BLICK & DRISCOLL Springer-Verlag. 453pp. bridgeUniv.Press. 274pp. CloetinghS, McQueen H, Lambeck K. 1985. On Galloway WE.1989.Geneticstratigraphic sea tectonic mechanism for regionalsea-level quencesin basinanalysisI: architectureand variations,EarthPlanet.Sci. Lett. 75:157-66 genesis of flooding-surfacebounded deposiCloetinghS, WonelR. 1985. Regionalstress tional units. Am.Assoc.Petrol.Geol.Bull. field of the IndianPlate. Geophys. Res.Letts. 73:125-42 12:77-80 Garcfa-Mond6jarJ, Femfmdez-Mendiola PA. CrossTA,LessengerMA.1988.Seismicstratig1993. Sequencestratigraphy and systems raphy.Annu.Rev.EarthPlanet.Sci. 16:319- tracts of a mixedcarbonateandsiliciclastic 54 platform-basinsetting: the albian of Lunada DamG, SurlykF. 1992. Forcedregresssionsin andSoba,northernSpain.Am.Assoc.Petrol. a large wave-and storm-dominatedanoxic Geol.Bull. 77:245-75 lake, Rhaetian-Sinemurian KapStewartFor- GoetzeG, EvansB. 1979. Stress andtemperamation,F.ast Greenland.Geology20:749-52 ture in the bendinglithosphereas constrained DemarestJMII, Kraft JC. 1987.Stratigraphic by experimentalrock mechanics.Geophys.J. recordof Quaternary sea levels: implications R. Astron. Soc. 59:463-78 for moreancientstrata. In Sea-LevelFluctua- GreenleeSM,DevlinWJ, Miller KG,Mountain tion andCoastalEvolution,ed. 13 Nummedal, GS,FlemingsPB. 1992. Integrated sequence OHPilkey, JD Howard,pp. 223-39. Soc. stratigraphy of Neogene deposits, NewJerEcon.Paleontol.MineralSpec. PubLNo.41. sey continentalshelf and slope: comparison 267pp. with the Exxonmodel.Geol.Soc. Am.Bull. Devlin WJ, Rudolph KW,ShawCA, Ehman 104:1403-1l KD.1993.Theeffect of tectonicandeustatic Grotzinger JP, AdamsRD,McCormick DS,Mycycles on accommodationand sequencerowP. 1989.Sequencestratigraphy,correlastratigraphic frameworkin the UpperCretions betweenWopmay orogenand Kilohigok taceous foreland basin of southwestern basin, andfurther investigationsof the Bear Wyoming. See Posamentieret al 1993, pp. Creek Group(GoulburnSupergroup),Dis501-20 trict of Mackenzie, N.W.T.Geol.Surv. Can. DottRHJr, ed. 1992.Eustasy:The Historical Pap. 89-1C:107-19 Upsand Downsof a MajorGeologicalCon- Handford CR, Loucks RG, 1993. Carbonate cept. Geol.Soc. Am.Mem.180. 111pp. depositionalsequencesandsystemstracts-Driscoll NW.1992. Tectonicanddepositional responsesof carbonateplatformsto relative processesinferredfromstratal relationships. sea-level changes.SeeLoucks&Sarg 1993, pp. 3-41 PhDdissertation. Columbia Univ., NewYork. 464pp. HaqBU.1,99I. Sequence stratigraphy,sea-level DriscollNW,HoggJR, Christie-BlickN, Karner change,andsignificancefor the deepsea. In GD.1995.Extensionaltectonicsin the Jeanne Sedimentation,TectonicsandEustasy. Sead’ArcBasin:implicationsfor the timingof Level Changesat Active Margins,ed. DIM break-upbetweenGrandBanksand Iberia. In Macdonald, pp. 3-39. Int. Assoc.Sedimentol. Opening of the NorthAtlantic, ed, RAScrutSpec.Publ.12. 518pp. ton. Geol.Soc. London Spec.Publ.In press HaqBU,HardenbolJ, Vail PR. 1987.ChronolDdscollNW,KarnerGD.1994. Flexuraldeforogyof fluctuating sea levelssincetheTriassic. mationdue to Amazon Fan loading: a feedScience235: 1156-67 backmechanism affecting sedimentdelivery HaqBU,HardenbolJ, Yall PR. 1988. Mesozoic to margins.Geology22:1015-18 and Cenozoicchronostratigraphyandcycles EbdonCC, Fraser A J, Higgins AC,Mitchof sea-level change.SeeWilguset al 1988, pp. 71-108 ener BC,Strank ARE.1990. The Dinantian stratigraphy of the East Midlands:a seis- Helland-HansenW,KendallCGStC,Lerche I, mostratigraphic approach.J. Geol.Soc. Lon, NakayamaK. 1988. A simulation of condon 147:519-36 tinental basin marginsedimentationin reEmbryAE1988. Triassic sea-level changes: sponse to crustal movements, eustatic sea evidence from the CanadianArctic Arlevel change, and sediment accumulation chipelago.SeeWilguset al 1988,pp. 249-59 rates. Math.Geol.20:777-802 EugsterHP,HardieLA.1975.Sedimentation in Heller PL, AngevineCL, WinslowNS, Paola an ancient playa-lakecomplex:the Wilkins C. 1988. Two-phase stratigraphic modelof Peak Member of the GreenRiver Formation foreland-basinsequences.Geology16:501-4 of Wyoming. Geol. Soc. Am.Bull 86:319-34 Heller PL, BowdlerSS, ChambersHP, Coogan Flint SS, BryantID, eds. 1993.TheGeological JC, HagenES, et al. 1986.Timeof initial Modellingof HydrocarbonReservoirs and thrustingin the Sevierorogenicbelt, IdahoOutcropAnalogues.Int, Assoc. Sedimentol, Wyoming and Utah. Geology14:388-91 Spec.Publ. 15. 269pp. Hettinger PD, McCabe PJ, ShanleyKW.1993. FrakesLA,FrancisJE, SyktusJI. 1992.Climate Detailedfacies anatomy of transgressiveand Modesof the Phanerozoic.Cambridge:Cam- highstandsystemstracts fromthe UpperCre- Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCE STRATIGRAPHY 475 taceousof southernUtah,U.S.A.SeeWeimer Weimer&Posamentier1993, pp. 393-410 &Posamentier1993, pp. 43-70 KossJE, EthddgeFG, Schumm SA. 1994. An experimental studyof the effectsof base-level HolmesAE, Chdstie-Blick N. 1993. Origin changeonfluvial, coastalplainandshelf sysof sedimentarycycles in mixedearbonatesiliciclastic systems: an examplefrom tems.J. Sedimentol,Res. B64:90-98 the Canningbasin, WesternAustralia. See LambeckK. 1983. The role of compressive forces in intracratonic basinformationand Loucks&Sarg 1993, pp. 181-212 Jacquin T, Arnaud-VanneauA, AmandH, mid,plate orogenics. Geophys.Res. Lett. Ravenne C, Vail PR.1991.Systemstracts and 10:845-48 depositionalsequences in a carbonatesetting: LambeckK, McQueenHWS,Stephenson RA, D. 1984. Thestate of stress within a studyof continuousoutcropsfromplatform Denham to basin at the scale of seismiclines. Mar the Australian continent. Ann. Geophys. Petrol Geol.8:122-39 2:723-41 JamesNP.1984. Shallowing-upward sequences Lawrence DT,DoyleM,AignerT. 1990.Stratiin carbonates. In Facies Models,ed. RG graphicsimulationof sedimentarybasins: conceptsandcalibration, Am.Assoc,Petrol. Walker,pp. 213-28.Toronto:Geosci.Can. ReprintSer. 1. 317pp. 2nded. Geol. Bull 74:273-95 JansaLF,Wade JA. 1975.Geology of the conti- LeckieDA,PosamentierHW,Lovell RWW, eds. nental marginoffNovaScotia andNewfound- 1991. NUNA Conf. on High-ResolutionSeland. Geol.Surv.Can.Pap.74-30:51-105 quenceStratigraphy.Toronto:Geol.Assoc. JerveyMT.1988.Quantitativegeologicalmod- Can.186 pp. elingof siliciclastic rocksequences andtheir LevyM,Chdstie-BlickN. 1991.Late Proteroseismicexpression.SeeWilguset a11988,pp. zoic paleogeographyof the eastern Great Basin. In PaleozoicPaleogeography of the 47-69 WesternUnitedStates--ll,ed. JDCooper,CH JohnsonJG, Klapper G, SandbergCA.1985. Devonian eustatic fluctuationsin Euramerica. Stevens,pp. 371-86.Pacific Section, SEPM, Geol.Soc. Am.Bull. 96:567-87 Book67, Vol.1. 461pp. JohnsonSD. 1994. HighResolution Sequence LindsayJF. 1987.Sequence stratigraphyanddeStratigraphy:InnovationsandApplications. positionalcontrolsin LateProterozoic-Early Liverpool:Univ.Liverpool.410pp. Cambriansedimentsof the Amadeus basin, Jordan TE, FlemingsPB. 1991. Large-scale central Australia, Am.Assoc.Petrol. Geol. stratigraphicarchitecture,eustatic variation, Bull. 71:1387--403 andunsteadytectonism:a theoretical evalu- LindsayJF, KennardJM,SouthgatePN.1993. ation. J. Geophys.Res. 96:6681-99 Application of sequence stratigraphyin an inKamerGD.1986. Effects of lithospherie in.tracratonie setting, Amadeus basin, central planestress on sedimentary basin stratigraAustralia. See Posamentieret al 1993,pp. phy. Tectonics5:573-88 605-31 KarnerGD,Driscoll NW,WeisselJK. 1993.Re- LoucksRG,Sarg JF, eds. 1993. Carbonate Sesponseof the lithosphereto in-planeforce quenceStratigraphy.Am.Assoc.Petrol.Geol. variations.EarthPlanet.Sci. Lett. 114:397- Mere.57. 545pp. 416 Loutit TS,ed. 1992.Sea-LevelWorking Group. Karner GD,Watts AB.1983. Gravity anoma- JOIDES J. 18(3):28-36 lies andflexureof the lithosphereat mountainLoutit TS, HardenbolJ, Vail PR, BaumGR. ranges. J. Geophys.Res. 88:10,449-77 1988. Condensed sections: the key to age KendallCGStC, LereheI. 1988.Therise andfall determinationsandcorrelationof continenof eustasy.SeeWilguset al 1988,pp. 3-17 tal marginsequences.SeeWilguset al 1988, KendallCGStC,MooreP, WhittleG, CannonR. pp. 183-213 1992.Achallenge:Is it possibleto determine McAlpineKD.1990. Mesozoicstratigraphy, eustasyanddoesit matter?SeeDott1992,pp. sedimentaryevolution,andpetroleumpoten93-107 tial of the Jeanned’Arcbasin,GrandBanksof Kerans C, NanceHS. 1991. High frequency Newfoundland. Geol. Surv. Can. Pap.89-17 cyclicityandregionaldepositionalpatternsof Miller KG,WrightJD, FairbanksRG.1991.Unthe GrayburgFormation,GuadalupeMoun- locking the ice house: Oligocene-Miocene tains, NewMexico.In SequenceStratigraoxygenisotopes,eustasy,andmarginerosion. J. Geophys.Res. 96:6829-48 phy, Facies,andReservoirGeometries of the San Andres, Grayburg,and QueenForma. Mitchum RMJr. 1977.Seismicstratigraphy and tions, GuadalupeMountains,NewMexico globalchangesof sea level, part 11: glossary and Texas, ed. S Meader-Roberts,MGCanof termsusedin seismicstratigraphy.SeePaydelada, GEMoore,pp. 53-69. PermianBasin ton 1977,pp. 205-12 section, SEPM (Soc. Sediment.Geol.)Publ. MitchumRMJr, Van WagonerJC. 1991. 91-32.141pp. High-frequency sequencesand their stackKocurekG, HavholmKG.1993. Eolian event ing patterns: sequence-stratigraphic evidence stratigraphy--a conceptualframework.See of high-frequency eustatic cycles. Sediment. Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 476 CHRISTIE-BLICK & DRISCOLL Geol. 70:131-60 Montafiez IP, Osleger DA.1993. Parasequence stacking patterns, third-order accommodation events, and sequence stratigraphy of Middle to Upper Cambrian platform carbonates, BonanzaKing Formation, southern Great Basin. See Loucks & Sarg 1993, pp. 305-26 Mutti E, Davoli G, MoraS, Sgavetti M, eds. 1994. The Eastern Sector of the SouthCentral Folded Pyrenean Foreland: Criteria for Stratigraphic Analysis and Excursion Notes. Second High-Resolution Sequence Stratigraphy Confi 83 pp. North American Commissionon Stratigrapbic Nomenclature. 1983. North AmericanStratigraphic Code.Am. Assoc. Petrol. Geol. Bull. 67:841-75 NormarkWR,Posamentier HW,Mutti E. 1993. Turbidite systems: state of the art and future directions. Rev. Geophys.31:91 - 116 Nummedal D, Cole RD. 1994. The Book Cliffs--again: relative sea level fail and depositional systems response. See Posamentier & Mutti 1994, pp. 147-51 NummedalD, RemyR, eds. 1989. Cretaceous Shelf Sandstonesand Shelf Depositional Sequences, Western Interior Basin, Utah, Colorado and NewMexico. 28th Int. Geol. Congr. Field Trip GuidebookTl19. Washington,DC: Am. Geophys. Union. 87 pp. Officer CB, Drake CL. 1985. Epeirogeny on a short geological time scale. Tectonics 4:60312 Olsen PE. 1986. A 40-million-year lake record of early Mesozoicorbital climatic forcing. Science 234:842-48 Olsen PE. 1990. Tectonic, climatic, and biotic modulations of Lacustrine ecosystems-examples from NewarkSupergroup of eastern North America. In Lacustrine Basin Exploration--Case Studies and Modern Analogs, ed. BJ Katz, pp. 209-24. Am. Assoc. Petrol. Geol. Mem.50. 340pp. Payton CE, ed. 1977. Seismic Stratigraphy-Applications to HydrocarbonExploration. Am. Assoc. Petrol. Geol. Mem.26. 516 pp. Plint AG. 1988. Sharp-based shoreface sequences and "offshore bars" in the Cardium Formationof Alberta: their relationship to relative changesin sea level. See Wilguset al 1988, pp. 357-70 Plint AG. 1991. High-frequency relative sealevel oscillations in UpperCretaceous shelf elastics of the Alberta foreland basin: possible evidence for glacio-eustatic control? In Sedimentation, Tectonics and Eustasy, Sea Level Changesat Active Margins, ed. DIM Macdonald,pp. 409-28. Int. Assoc. Sedimentol. Spec. Publ. 12. 518pp. Plint AG.1994. Sheep from goats: separating eustatic from tectonic controls on 4th order sequence development: CenomanianDunve- gan Formation, Alberta foreland basin. See Posamentier & Mutti 1994, pp. 153-58 Posamentier HW,Allen GP. 1993. Siliciclastic sequencestratigraphic patterns in foreland ramp-type basins. Geology21:455-58 Posamentier HW,Allen GP, James DP. 1992b. High resolution sequence stratigraphy--the East Coulee Delta, Alberta. J. Sediment. Petrol. 62:310-17 Posamentier HW,Allen GP, James DP, Tesson M. 1992a. Forced regressions in a sequence stratigraphic framework: concepts, examples, and exploration significance. Am. Assoc. Petrol. Geol. Bull 76:1687-709 Posamentier HW,Chamberlain CJ. 1993. Sequencestratigraphic analysis of VikingFormation lowstand beach deposits at Joarcam Field, Alberta, Canada.See Posamentieret al 1993, pp. 469-85 Posamentier HW,James DP. 1993. Anoverview of sequence-stratigraphic concepts: uses and abuses. See Posamentieret al 1993, pp. 3-18 Posamentier HW,Jervey MT, Vail PR. 1988. Eustatic controls on clastic deposition I-conceptual framework.See Wilguset al 1988, pp. 109-24 Posamentier HW,Mutti E, convenors. 1994. Second High-Resolution Sequence Stratigraphy Conference. Int. Union Geol. Sci. and Global Sed. Geol. Prog. 221 pp. Posamentier I-IW, SummerhayesCE Haq BU, Allen GP, eds. 1993. Sequence Stratigraphy and Facies Associations. Int. Assoc. Sedimentol. Spec. Publ’18. 644 pp. Posamentier HW,Vail PR. 1988. Eustatic controls on clastic deposition II--sequence and systems tract models. See Wilguset al 1988, pp. 125-54 Pratt BR, James NP, CowanCA. 1992. Peritidal carbonates. In Facies Models,ed. RGWalker, NPJames, pp. 303-22. Toronto: Geol. Assoc. Can. 409 pp. Prave AR. 1991. Depositional and sequence stratigraphie frameworkof the LowerCambrian Zabriskie Quartzite: implications for regional correlations and the Early Cambrian paieogeographyof the Death Valley region of California and Nevada.Geol. Soc. Am. Bull. 104:505-15 Reynolds DJ, Steckler MS, Coakley BJ. 1991. The role of the sediment load in sequence stratigraphy: the influenceof flexurai isostasy and compaction. J. Geophys. Res. 96:693149 Ross WC.1990. Modelingbase-level dynamics as a control on basin-fill geometriesand facies distribution: a conceptual framework.In Quantitative DynamicStratigraphy, ed. TA Cross, pp. 387-99. EnglewoodCliffs, NJ: Prentice-Hall. 625 pp. Ross WC,Halliwell BA, May JA, Watts DE, Syvitski JPM. 1994. Slope readjustment: a newmodel for the developmentof submarine Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. SEQUENCE STRATIGRAPHY fans and aprons. Geology22:511-14 Salvador A. 1987. Unconformity-boundedstratigraphie units. Geol. Soc. Am.Bull, 98:23237 Sarg JF. 1988. Carbonatesequencestratigraphy. See Wilguset al 1988, pp. 155-81 Sarg JF. 1989. Middle-late Permiandepositional sequences, Permian basin, west Texas and NewMexico. In Atlas of Seismic Stratigraphy, ed. AWBally, pp. 140-54. Am.Assoc. Petrol. Geol. Stud. Geol. No. 27, Vol. 3.244 PP. Sarg JF, Lehmann PJ. 1986. Lower-Middle Guadalupianfacies and stratigraphy, San Andres/Grayburg formations, Permian basin, Guadalupe Mountains, New Mexico and Texas. In Field Trip Guidebook, San Andres/Grayburg Formations, Guadalupe Mountains, NewMexico and Texas, ed. GE Moore, GLWilde, pp. 1-35. Permian basin section. Soc. Econ. Paleontol. Mineral. Publ. 86-25. 144 pp. Schlager W, Reijmer JJG, Droxler A. 1994. Highstand shedding of carbonate platforms. J. Sedimentol, Res. 64:270-81 Schlanger SO. 1986. High-frequency sea-level fluctuations in Cretaceoustime: an emerging geophysical problem. In History of Mesozoic and Cenozo&Oceans,ed. KJ Hsii, pp. 61-74. Am. Geophys. Union Geodyn. Ser. 15 Shanley KW,McCabePJ. 1994. Perspectives on the sequence stratigraphy of continental strata. Am. Assoc. Petrol. Geol. Bull, 78:54468 Sinclair HD, CoakleyB J, Allen PA, Watts AB. 1991. Simulationof foreland basin stratigraphy using a diffusion modelof mountainbelt uplift and erosion: an examplefrom the central Alps, Switzerland. Tectonics 10:599-620 Sloss LL. 1950. Paleozoic stratigraphy in the Montanaarea. Am. Assoc. Petrol. Geol. Bull. 34:423-51 Sloss LL. 1963. Sequencesin the eratonic interior of North America. Geol. Soc. Am. Bull 74:93-114 Sloss LL.1988. Forty years of sequencestratigraphy. Geol. Soc. Am. Bull, 100:1661-65 Sloss LL.1991. Thetectonic factor in sea level change: a countervailing view. J. Geophys. Res. 96:6609-617 Sloss LL, KrumbeinWC,Dapples EC. 1949. Integrated facies analysis. In SedimentaryFacies in Geologic History, ed. CR Longwell, pp. 91-124. Geol. Soc. Am. Mere.39. 171 pp. Sonnenfeld MD,Cross TA. 1993. Volumetric partitioning and facies differentiation within the Permian Upper San Andres Formation of Last Chance Canyon, Guadalupe Mountains, NewMexico. See Loucks & Sarg 1993, pp. 435-74 Southgate PN, Kennard JM, Jackson MJ, O’Brien PE, Sexton MJ. 1993. Reciprocal lowstandclastic and highstandcarbonate sed- 477 imentation, subsurface Devonianreef complex, Canningbasin, WesternAustralia. See Loucks & Sarg 1993, pp. 157-79 Steckler MS, Reynolds DJ, Coakley B J, Swift BA,Jarrard R. 1993. Modellingpassive margin sequencestratigraphy. See Posamentieret al 1993, pp. 19-41 Steel R J, MaehleS, Nilsen H, Roe SL, Spinnangr A. 1977. Coarsening-upward cycles in the alluvium of Homelenbasin (Devonian), Norway:sedimentary response to tectonic events. Geol. Soc. Am. Bull. 88:1124-34 Suter JR, Berryhill HL, Penland S. 1987. Late Quaternarysea-level fluctuations and depositional sequences, southwest Louisiana continental shelf. In Sea-Level Fluctuation and Coastal Evolution, ed. D Nummedal, O Pilkey, J Howard,pp. 199-219. Soc. Econ. Paleontol. Mineral. Spec. Publ. No. 41. 267 PP. Swift DJP, Phillips S, ThorneJA. 1991. Sedimentationon continental margins, V: parasequenees. In Shelf Sandand SandstoneBodies. Geometry,Facies and SequenceStratigraphy, ed. DJP Swift, GF Oertel, RWTillman, JA Thome,pp. 153-87. Int. Assoc. Sedimentol. Spec. Publ. 14. 532 pp. Sykes LR, Sbar ML.1973. Intraplate earthquakes, lithospheric stresses and the driving mechanismof plate tectonics. Nature 245:298-302 Tankard AJ, Welsink HJ, Jenkins WAM. 1989. Structural styles and stratigraphy of the Jeanne d’Arc basin, Grand Banks of Newfoundland. In Extensional Tectonics and Stratigraphy of the North Atlantic Margins, ed. AJ Tankard, HRBalkwill, pp. 265-82. Am. Assoc. Petrol. Geol. Mem.46. 64l pp. Tesson M, Allen GP, Ravenne C. 1993. Late Pleistocene shelf-perched lowstand wedges on the Rh6necontinental shelf. See Posamentier et al 1993,pp. 183-96 Tesson M, Gensous B, Allen GP, Ravenne C. 1990. Late Quaternary deltaic lowstand wedges on the Rh6ne continental shelf, France. Mar. Geol. 91:325-32 Underhill JR. 1991. Controls on late Jurassic seismic sequences, Inner MorayFirth, UK North Sea: a critical test of a key segment of Exxon’soriginal global cycle chart. Basin Res. 3:79-98 Vail PR. 1987. Seismicstratigraphy interpretation using sequencestratigraphy. Part I: Seismic stratigraphy interpretation procedure. In Atlas of Seismic Stratigraphy, ed. AWBally, pp. 1-10. Am.Assoc. Petrol. Geol. Stud. Geol. No. 27, Vol. 1. 125 pp. Vail PR. 1992.The evolution of seismic stratigraphy and the global sea-level curve. See Dott 1992, pp. 83-91 Vail PR, Audemard E Bowman SA, Eisner PN, Perez-Cruz C. 1991. The strati- Annual Reviews www.annualreviews.org/aronline Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only. 478 CHRISTIE-BLICK & DRISCOLL graphicsignaturesof tectonics, eustasyand of WesternInterior, USA.In lnterregional sedimentology--anoverview.In Cyclesand Unconforraities and Hydrocarbon AccumuEvents in Stratigraphy, ed. G Einsele, W lation, ed. JS Schlee,pp. 7-35. Am.Assoc. Ricken,A Seilacher, pp. 617-59. Berlin: Petrol.Geol.Mere.36. 184pp. Springer-Verlag. 955pp. Weimer P. 1989. Sequencestratigraphy of the Vail PR,Hardenbol J, ToddRG.1984.Jurassic MississippiFan(Plio-Pleistocene),Gulf unconformities, chronostratigraphy, andseaMexico.Geol.Mar.Lett. 9:185-272 level changesfromseismicstratigraphyand WeiraerP, PosamantierHW,eds. 1993.Silicibiostratigraphy.In InterregionalUnconfor- clastic Sequence Straligraphy:RecentDevelmities and Hydrocarbon Accumulation,ed. opmentsandApplications.Am.Assoc.Petrol. JS Schlee, pp. 129-44.Am.Assoc. Petrol. Geol.Mere.58. 492pp. Geol.Mere.36. 184pp. WeisselJK, KarnerGD.1989.Flexural uplift unloadingof Vail PR, MitchumRMJr, ToddRG,Widmier of rift flanks dueto mechanical JM, Thompson S III, et al. 1977. Seismic the lithosphereduringextension.J. Geophys. stratigraphyandglobalchangesof sea level. Res. 94:13,919-50 See Payton1977, pp. 49-212 WemickeB, AxenGJ. 1988. On the role of VanWagonerJC, MitchumRM,CampionKM, isoStasyin the evolutionof normalfault sysRahmanian VD.1990.Siliciclastic Sequence tems. Geology16:848-51 Stratigraphyin WellLogs, Cores,and Out- WheelerHE.1958.Time-stratigraphy.Am.Ascrop.v: Conceptsfor High-Resolution Corresoc. Petrol.Geol.Bull. 42:1047-63 lation of gimeandFacies.Am.Assoc.Petrol. WilgusCK,HastingsBS, KendallCGStC,PosaGeol.Methodsin ExplorationSeries, No. Z mentier HW,RossCA,VanWagoner JC, eds. 55 pp. 1988.Sea-LevelChanges:AnIntegratedApproach.Soc. Econ.Paleontol.Mineral.Spec. Van WagonerJC, NummedalD, Jones CR, Publ.No.42. 407pp. Taylor DR,Jennette DC,Riley GW.1991. Sequencestratigraphyapplications to shelf Winter H de la R, Brink MC.1991. Chronosandstonereservoirs.Am. Assoc.Petrol.Geol. stratigraphic subdivisionof the Witwatersrand basin based on a WesternTransvaal FieMConf. Van WagonerJC, Posamentier HW,Mitchum compositecolumn.S. Afr. J. Geol.94:191RMJr, Vail PR, Sarg JF, et al. 1988. An 203 overviewof the fundamentalsof sequence WoodLJ, Ethridge FG, Schumm SA. 1993. stratigraphyandkeydefinitions. SeeWilgus Theeffects of rate of base-levelfluctuation et al 1988,pp. 39-45 on coastal plain, shelf and slope deposiWalker RG.1990. Facies modelingand setional systems:an experimentalapproach. SeePosamentieret al 1993,pp. 43-53 quence~tratigraphy. J. Sediment.Petrol. 60:777-86 YangC-S, NioS-D.1993.Applicationof highWalkerRG,Plint AG.1992. Wave-and stormresolutionsequence stratigraphyto the upper dominated shallowmarinesystems.In Facies Rotliegandin the Netherlandsoffshore. See Models,ed. RGWalker,NPJames,pp. 219Weimer&Posamentier1993, pp. 285-316 238. Toronto:Geol.Assoc.Can.409 pp. Yingling VL, Heller PL. 1992. Timingand recordof forelandsedimentationduringthe WatkinsJS, MountainGS, convenors. 1990. Role of ODPdrilling in the investigation initiation of the Sevierorogenicbelt in cenof global changesin sea level. Reportof tral Utah.BasinRes. 4:279-90 JOI]USSACWorkshop ZobackML,ZobackMD,AdamsJ, Assumpcao S, et al. 1989.Globalpatternsof Weimer RJ. 1984.Relation of unconformities, M,Bergrnan tectonics, andsea-levelchanges,Cretaceous tectonic stress. Nature341:291-98 Annu. Rev. Earth. Planet. Sci. 1995.23:451-478. Downloaded from arjournals.annualreviews.org by Columbia University on 09/17/05. For personal use only.