May All 2006

Marine and Petroleum Geology

ed

Jo

BP Exploration, Chertsey road, Sunbury-upon-Thames, Middlesex, TW16 7LN, UKbBP Exploration and Production, 14 Road 252, Maadi, Digla, Cairo, Egypt

cBP Amoco Exploration 501 Westlake Park Boulevard, Houston, TX 77253-3092, USA

r 2006 Elsevier Ltd. All rights reserved.

Broucke et al., 2004; Clemenceau et al., 2000; Deptuck etal., 2003; Fonnesu, 2003; Fugitt et al., 2000; Humphreys etal., 1999; Kendrick, 2000; Kolla et al., 2001; Mayall and

carbon industry has substantially driven forward ourunderstanding of these depositional systems. Much of ourincrease in knowledge has come from the observations and

ARTICLE IN PRESSinterpretations made possible by the increasingly availablehigh quality 3D seismic data, particularly from WestAfrica (e.g. Navarre et al., 2002). Interpretation of the

0264-8172/$ - see front matter r 2006 Elsevier Ltd. All rights reserved.

doi:10.1016/j.marpetgeo.2006.08.001

Corresponding author. Tel.: +441932 762 000.E-mail address: [email protected] (M. Mayall).Keywords: Turbidite system; Channel; Reservoir

1. Introduction

Turbidite channels are recognised as very importanthydrocarbon reservoir types in almost all areas and settingswhere deep-water facies are being explored, appraised orproduced (Beydoun et al., 2002; Brami et al., 2000;

OByrne, 2002; Mayall and Stewart, 2000; Navarre et al.,2002; Posamentier, 2003; Posamentier and Kolla, 2003;Posamentier et al., 2000; Prather, 2003; Prather et al., 1998;Sikkema and Wojcik, 2000; Wonham et al., 2000; Weimerand Slatt, 2004). Over the last 510 years, in particular, thesignicance of turbidite channel reservoirs to the hydro-Received 22 September 2005; received in revised form 12 July 2006; accepted 15 July 2006

Abstract

Turbidite channels are important but frequently complex reservoirs in the exploration, appraisal and development of deep-water

facies. Over the last 10 years in particular, high-resolution seismic data and extensive outcrop studies have increased our knowledge of

the complexity of these sedimentary bodies. Such is their variability and complexity that developing and applying single or even multiple

depositional models has limited applicability. Instead, we recognise an alternative approach to help rapidly evaluate turbidite channel

reservoirs. The paper mainly concerns the evaluation of large erosionally conned 3rd-order channels, typically 13 km wide and

50200m thick.

Each channel is unique but each generally has four recurring elements namely, the sinuosity, the facies, repeated cutting and lling and

the stacking patterns.

Several different styles of sinuosity can be identied, each having different implications for sand distribution. Four main facies can

often be recognised on seismic, calibrated by cores and logs; a basal lag, slump/debris ows, high net:gross stacked channels and low N:G

channel levees. Most channels contain all of these facies but in widely varying proportions.

Repeated cutting and lling is a feature of just about every channel studied. The process has major implications for reservoir and non-

reservoir distribution.

The stacking patterns of the 4/5th-order channels within the 3rd-order channel can have a critical impact on facies and heterogeneity

distribution and can strongly inuence well design and even potentially the development concept.

This paper discusses the impact of each of these elements on exploration, appraisal and development issues.Turbidite channel reservoirsKand effective

Mike Mayalla,, Eda23 (2006) 821841

y elements in facies predictionevelopment

nesb, Mick Caseyc

www.elsevier.com/locate/marpetgeo

high-resolution seismic data is being supported by increas-ing well log and core data. Accompanying the subsurfacedata, outcrop analogue studies and studies of modern andPleistocene channel systems have resulted in an extensiveand mounting literature on the nature of turbidite channelreservoirs (Abreu et al., 2003; Adedayo et al., 2005;Babonneau et al., 2002; Beaubouef, 2004; Beaubouefet al., 1999; Browne and Slatt, 2002; Busby and Camacho,1998; Campion et al., 2000; Clark and Gardiner, 2000;Clark and Pickering, 1996a, b; Coleman, 2000; Cook et al.,1994; Cronin, 1995; Cronin and Kidd, 1998; Cronin et al.,2000, 2002; Damuth et al., 1983; DeVries and Lindholm,1994; Elliott, 2000; Emmel and Curray, 1985; Eschardet al., 2003; Gardner and Borer, 2000; Gardner et al., 2003;Haughton, 2000; Hickson and Lowe, 2002; Johnson et al.,2001; Kenyon et al., 1995; Kirschner and Bouma, 2000;Kneller, 2003; Link and Stone, 1986; Lomas et al., 2000;May and Warme, 2000; Morris and Busby-Spera, 1988,1990; Mulder et al., 2003; Peakall et al., 2000; Pirmez et al.,2000; Pirmez and Imran, 2003; Prather et al., 2000; Samuelet al., 2003; Slatt, 2000; Slatt et al., 1994, 2000; Spinell andField, 2001; Walker, 1975; Weimer and Slatt, 2004). Thesenumerous, detailed and comprehensive studies havefocused on channel classication, specic aspects of

cutting stratigraphy (Fig. 1). In our view, each channel isunique i.e. one model, or even a series of models, cannot besuperimposed everywhere. However, we believe that thereare a series of recurring features that can and should beinvestigated to rapidly advance the evaluation of anyturbidite channel system. The aim of this paper is tosuggest an approach which can quickly and efcientlybreak down this complexity into elements that can readilybe related to reservoir distribution and heterogeneitieswithin the channel.In presenting a fairly pragmatic approach we recognise

that there are many elements of turbidite channel deposi-tional process and controls that we do not understand.However, even without this full understanding we are ableto focus on making practical, applied, decisions regardingthe challenges facing exploration, appraisal and productionof the turbidite channel reservoirs.We believe that the problem of describing and interpret-

ing turbidite channels can be broken into four areasthenature of the sinuosity, the facies, the recognition ofrepeated cutting and lling episodes and the stackingpatterns of the channels. The sections below describe eachof these major elements.

ARTICLE IN PRESS

y o

M. Mayall et al. / Marine and Petroleum Geology 23 (2006) 821841822channel morphology, depositional processes, detailedstudies of individual channels or studies of regionalsystems.When interpreting turbidite channels on seismic data, the

image can initially be one of a bewildering complexity ofamplitude variations, seismic facies and complicated cross-

Fig. 1. The large erosional channels can display a bewildering complexiterosional surfaces shown in (b). Each channel is unique but there are com

heterogeneities.2. Stratigraphic setting and terminology

In describing channels and their internal architecture awide range of terminology has been proposed to cover therange of scales of features that can be observed e.g. geo-body, channel complex, channel storey, channel-complex

f surfaces, amplitude variations and seismic facies (a). Interpretation ofmon themes to help us understand and predict the reservoir facies and

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Peset, conned-channel complex system (Gardner and Borer,2000; Navarre et al., 2002; Sprague et al., 2002). Werecognise the value of these terms, but for the purposes ofthis work we are using a simple terminology, describing thechannels and their internal architecture by what we believeto be their sequence stratigraphic setting.Like most workers we recognise that turbidite channels

form a continuous spectrum from erosionally conned,through a combination of erosion and constructionallevees, to channels entirely conned by levees. In thispaper, we are largely focussing on large erosionallyconned channels (Fig. 2). However, most of the aspectsof turbidite channels we will describe are applicable also tochannels with a combination of erosional and leveeconnement. In channels that are wholly conned by

Fig. 2. Typical characteristics of the 3rd-order erosional channels; 13 km wide

multiple stacking of smaller channels. Map is an RMS amplitude extraction

Location of seismic shown with red line on the map.

Fig. 3. Summary of terminology and streum Geology 23 (2006) 821841 823levees, many of the elements are relevant but there alsoappear to be differences that are beyond the scope of thispaper to discuss. The channels that we are considering aretypically 13 km wide (but can be wider) and 50200mthick (Figs. 2 and 3). They usually have a well-denederosional base and a complex internal ll. In sequencestratigraphic terms, the large erosional base can commonlybe demonstrated to be a 3rd-order bounding surface(12ma) and smaller scale erosional cuts within it to be4th- and 5th-order surfaces as discussed below. Thesmallest channel element we recognise, typically a fewhundred metres wide and 1030m thick, we call individualchannels.The denition of the large erosionally based channels as

3rd-order sequence boundaries can be demonstrated by

, 50200m thick, conned by an erosional base, often sinuous and lled by

0100ms above the red horizon which is interpreted as the channel base.

atigraphic setting used in this paper.

to recognise that there are at least four causes of sinuosityin turbidite channels; initial erosive base, lateral stacking,lateral accretion and sea-oor topography. Different stylesof channel sinuosity have been pointed out by Beydounet al., 2002; Kolla et al., 2001, who refer to elementary andcomplex channel migration. The different styles of sinuos-ity have different implications for the reservoir distributionand heterogeneity patterns.

3.1. Initial erosive base

In many cases, mapping of the original erosional con-nement of the channel shows a sinuous form (Fig. 5). Thisis essentially an erosional effect caused by turbidite owsby-passing and continuing downslope. In some cases, theouter position of a bend has also been extended byrotational sliding and slumping from the channel walls. Inmost examples, we see no obvious effect, in terms ofunderlying lithology, for the location of the sinuous bendsand conclude that the erosionally created sinuosity is aninherent part of the turbidite ows and channel formation.In theory, the sinuosity generated during the erosion

ARTICLE IN PRESS

Fig. 4. Sinuosity in the large 3rd-order erosional channels is common;

however. several causes of the sinuosity can be recognised as described in

gures following.

troltheir stratigraphic relationship between major 3rd-ordermaximum ooding surfaces (Fig. 3). The 3rd-ordermaximum ooding surfaces often have sufcient biostrati-graphic control and diagnostic forms to provide acondent tie to the chronostratigraphic time scale andlinked into a sequence stratigraphic framework. Exceptingthe dominance of other controlling factors, it appears thatthe majority of the ll of these major channels is associatedwith periods of 3rd-order eustatic lowstand. Biostrati-graphic analyses also allow the 3rd-order transgressivesurface to be identied and show that this surface istypically overlain by dominantly hemipelagic shales.Hence, the thickness of the deposits associated with thelowstand systems tract is often much greater than theoverlying shale-prone sections relating to transgressive andhighstand systems. With the 3rd-order nature of the majorerosional channel complex determined, the nature of thecomplex ll can be further analysed. It should be noted thatdown depositional systems tract, in more distal settings, the3rd-order ll may become non-composite and split out intoseparate 4th-order channel systems resulting in channelbifurcation. In such circumstances, a well-dened biostrati-graphic framework is invaluable in aiding a correctinterpretation.In practice, the delineation of 4th- versus 5th-order

frequency events is often difcult to determine withcondence. In a slope system where channel activityswitches over time, periods of abandonment may resultfrom autocyclic events rather then be directly controlled byhigh-order eustatic cycles. Hence, if autocyclic processesdominate, the ll of any 3rd-order channel complex may bepurely a combination of stacked high-frequency eventsdeposited during periods when the given channel systemwas acting as an active conduit. Because of this difculty inbeing able to readily and systematically distinguish between4th- and 5th-order surfaces, in this paper, we refer to theerosional cuts within the 3rd-order erosional as 4/5th-ordersurfaces. We recognise that where the data allows, it can beuseful to specically interpret the 4/5th-order surfaces, it isnot usually necessary in order to make progress in breakingout the key elements for facies prediction.

3. Sinuosity

A spectacular feature of most modern turbidite channelsis the sinuosity that is regularly observed on sea-oorimage maps (e.g. Babonneau et al., 2002; Cronin et al.,2002; Damuth et al., 1983; Kenyon et al., 1995). Increas-ingly, seismic amplitude maps generated from older slopeturbidite channel sequences also show the same ubiquitoussinuosity (Fig. 4). (Beydoun et al., 2002; Deptuck et al.,2003; Fonnesu et al., 2003; Kolla et al., 2001; Mayall andOByrne, 2002; Mayall and Stewart, 2000; Navarre et al.,2002; Posamentier et al., 2000; Sikkema and Wojcik, 2000;Wonham et al., 2000). The sinuosity varies from occasional

M. Mayall et al. / Marine and Pe824bends in the channel to highly sinuous channels withnumerous cut-off bends. In our experience, it is importanteum Geology 23 (2006) 821841phase, could cause sands to subsequently accumulate at orupstream of the channel bends as a result of ow stripping.

ARTICLE IN PRESStrolM. Mayall et al. / Marine and PeHowever, in our experience, it is hard in most cases toestablish a preferred location of later turbidite sandsdeposited around the bends.

3.2. Lateral stacking

In some channels, a bend has formed due tosystematic lateral shifts of the smaller 100200m wide

Fig. 5. Sinuosity due to erosional base. Time map on the erosional base (arrow

represent deepest part of channel. Erosional base shows high degree of sinuos

Fig. 6. Prominent sinuous element in channel caused by systematic lateral stack

from a 30ms window in the middle of the channel ll.eum Geology 23 (2006) 821841 825channels. This appears to have occurred due to thechannel lling, shifting slightly laterally and re-incising.Fig. 6 shows an example which demonstrates a degreeof aggradation. Fig. 7 shows, through a series of super-imposed time-sequences maps, the sinuosity increaseof a channel from 1.2 at the base to 1.8 at the top. Thechannel is highly aggradational, in this example it isstrongly levee conned, and the sinuosity increases

ed) of the large erosional channel shown in seismic line. Darker red colours

ity.

ing of smaller 4/5th-order channels. Map is an RMS amplitude extraction

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Pe826through a series of discrete lateral step-wise shifts of thechannel.Lateral stacking of channels has been well documented

in a number of excellent outcrop areas (Campion et al.,2000; Clark and Pickering, 1996b; Gardner et al., 2003;Eschard et al., 2003), although in the outcrop cases it isdifcult to demonstrate if the stacking patterns seen in 2Dsection are related to the development of sinuosity in thechannels.As with many of the observations we can make, it is

unclear if this style of sinuosity in the channel is due todepositional processes or is a function of changes in sea-oor topography due to diapir or fault movement. Forexample, the lateral stacking seen in the Eocene turbiditechannels near Ainsa (Spain) are interpreted to be due tothrust movements (Clark and Pickering, 1996b).

3.3. Lateral accretion

On some channels, the sinuosity has been created bylateral migration of an open channel. In this case, a series

Fig. 7. Example of sinuosity caused by lateral stacking of channels. Channel

Channel migrates in a series of discrete steps.eum Geology 23 (2006) 821841of seismic reectors dip towards the channel (Fig. 8)marking the systematic lateral migration of the channels.In map view, traces of the dipping reectors show arcuatepatterns within the sinuous bends of the channel (Fig. 8).On the opposite side of the nal channel, the reectorsfrom older strata terminate against the channel edge. Thisarchitecture of turbidite channels has been thoroughlydocumented by Abreu et al. (2003) who refer to them aslateral accretion packages (LAPS) and fully document anumber of subsurface and outcrop examples. This parti-cular manifestation of the sinuosity in the channels is mostlike the lateral accretion well documented from meanderinguvial systems, with erosion on the outside of the bank anddeposition on the inner bank as a point bar. Images of thisstyle of sinuosity have received much attention anddiscussion particularly regarding depositional processes(e.g. Kolla et al., 2001; Peakall et al., 2000). It is probablyfair to say that we do not fully understand the processesthat form these features, but of all the styles of depositionalsinuosity, they are the most likely to be caused solelyby depositional process rather than partially or completely

bends show stacking patterns in appropriate direction to form sinuosity.

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Peby sea-oor topography. However, in our experience,this form of sinuosity in the channels is relativelyrare within the whole spectrum of turbidite channels.It is usually relatively thin, a few tens of metres beingtypical.Additionally, although Abreu et al. (2003) describe

sandy and amalgamated examples of this style of sinuosity,our experience is that low net to gross style (the non-amalgamated style of Abreu et al., 2003) is most common.In these forms the sands occur just as a basal lag withperhaps some sand occurring along the lower part of thedipping reectors. The nal channel is also dominantlymud-lled as evidenced by low amplitude seismic andconvex down compaction.

Fig. 8. Sinuosity formed by lateral accretion. RMS amplitude extraction map a

shown by dipping reectors) with mud-lled nal channel. Erosional terminat

Fig. 9. Sinuosity created by sea-oor expression of faults. RMS amplitude extr

seismic line is shown with white line. Channel shows a prominent bend as it reum Geology 23 (2006) 821841 8273.4. Sea-floor topography

As turbidite channels cross the slope there is inevitablysome control on their geometry due to contemporaneoussea-oor topography (Figs. 9 and 10). On many of themajor slope systems, salt or shale diapirism and associatedfaults create subtle to signicant sea-oor topography. Themost substantial topographic effects control the down-slope route and can cause major diversions of the channelorientation (Mayall and Stewart, 2000). On a more subtlescale, the sea-oor expression of the faults often appear tocause signicant bends in the channels. Although it is oftenhard to prove the cause, the repeated coincidence ofprominent channel bends and the location of faults,

nd seismic line (location shown in red on map). Channel accretes laterally,

ion of older reectors on right side (outer bend) of channel (arrowed).

action map is of a 30ms window in the middle of the channel. Location of

uns along the down-thrown side of a NWSE fault (arrowed).

tur

ll

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Pe828particularly associated with diapirism, seems to indicate acausal link. It seems that the channels divert around themaximum sea-oor expression of a fault and pass down-slope at the lateral tip-out of the topography.Examples of channel diversion at the sea-oor expres-

sion of faults in the present day is well known from modernfans e.g. the Var Fan (Cronin, 1995). From a conceptualpoint of view, it is possible that ow stripping at thesesharp channel bends may result in sands being depositedimmediately upstream of the bends.There has been considerable progress made on under-

standing the nature of turbidity current ow alongsubmarine channels and the potential for hyperpycnalows in deepwater (Das et al., 2004; Kneller, 2003; Mulderet al., 2003; Peakall et al., 2000; Pirmez et al., 2000; Pirmezand Imran, 2003). However, much remains poorly under-stood regarding the process of generating sinuosity indeepwater channels. For example, is there a process orcharacter of the ows that can generate different forms ofchannel sinuosity? Or are there a number of differentprocesses that create, at least supercially, similar lookingplanform geometries? It appears, in most cases, that a

et Spera, 1990).f these facies can be foundd Stewart (2000) indicatedf this complexity into four

Fig. 10. Sinuosity in part formed by sea-oor expression of faults.

Radiating and concentric faults from diapir in NE corner of image are

coincident with major bends in channel, examples arrowed. basal lags, slumps and debris ows, high N:G stacked channels, low N:G channel-levee.The rationale for dividing the channel-ll facies into

these four types is,

they are often recognisable even on poor quality seismic, they are the important elements for predicting reservoirdistribution and heterogeneity patterns,

they can, but not always, occur in a distinctive verticalsequence,

they can illustrate some of the major risks and pitfalls infacies prediction.

It is important to recognise that not all of these faciesnecessarily occur in every channel. However, dividing thechannel-ll lithologies in this way provides a useful modelfor considering the possible facies that can be present. Thisapproach provides a quick and systematic consideration ofreservoir facies, non-reservoir facies and potential barriersand bafes to uid ow.

4.1. Basal lags

Most erosionally conned turbidite channels have somemakinant it is practical to group all oin facies (Figs. 11 and 12):tha

turbidite channels; Mayall anin

However, while any and all o

al., 2003; Morris and Busby-rain (e.g. Beaubouef, 2004; Campion et al., 2000; Clark andPickering, 1996a, b; Cook et al., 1994; Cronin et al., 2000;Cronin and Kidd, 1998; Eschard et al., 2003; Gardnermu

positional processes; high- and low-density turbidites,d ows, debris ows, slides, slumps and hemi-pelagicdem boulders and conglomerates to almost entirely mud-s and encompass the whole spectrum of gravity-drivenfroThe sedimentary rock types that can occur withinbidite channels are clearly highly variable. They rangesingle channel seen on seismic may have sinuous elementsas a function of two or more of the processes describedabove. Although much remains to be understood regardingthe origins and causes of the sinuosity in channels, anessential element of the evaluation of turbidite channels ashydrocarbon reservoirs is an understanding of which stylesof sinuosity are present. It is important to recognise thatthere may be several styles of sinuosity present withdifferent implications for the reservoir distribution andheterogeneity patterns.

4. Facies

eum Geology 23 (2006) 821841d of basal lag formed when the channel was being cutd most of the turbidite ows were by-passing and

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Pedepositing their main sediment load further downslope.However, this phase of limited deposition within thechannels can take different forms (Fig. 12).

Coarse sands and conglomerates are probably the mostcommon form of basal lags comprising massive or poorlystratied intervals typically ranging from less than a metreto 5m thick (Fig. 12a). They usually appear to form a layerat the base of the channel but may locally thicken and thinin relation to irregularities on the erosional base. Where thechannels have not been deeply buried and most of thesands are acoustically soft (lower acoustic impedance thansurrounding shales), the basal lags are often acousticallyhard due to the presence of dense pebbles. In thesecircumstances, the basal lags make a very distinctiveseismic reector and can be an excellent aid to mappingthe base of the channels (Fig. 11b). The reservoir quality ofthe coarse sands and conglomerates can be variable but dueto the relatively larger size of the clasts in this facies theyhave the potential for being important as a high perme-ability interval.

Mudclast conglomerates are also common at the base ofthe channels. They are composed of intraformational

Fig. 11. (a) Simple model of facies in a channel ll and (b) seismic exampleum Geology 23 (2006) 821841 829mudclasts, within a sandy matrix, which have been erodedfrom the channel base and walls (Fig. 12b and c). Theconcentration of mudclasts varies, with the most intensiveconcentrations forming a mass of compacted clasts withjust small patches of sandy matrix. In this form, it ispossible that the facies could form a permeability barrier orbafe within the reservoir. Additionally, at the base ofsome channels there may be an interval several metres thickcontaining a number of mudclast conglomerate beds.Individually the beds may only be a few tens of metreswide but overall it is possible that the overall interval mayrespond as a zone of reduced transmissivity.

Shale drapes at the base of channels have beenincreasingly described from a number of outcrops (e.g.Gardner and Borer, 2000; Gardner et al., 2003; Eschardet al., 2003). They form as the main body of the turbiditeby-passes the channel and only the tail deposits mud andsilt (Fig. 12d and e). There is a good chance that these shaledrape by-pass deposits could form permeability barriers orbafes.We recognise at least three types of basal lag facies

deposition when the turbidites were largely by-passing the

e of simple ll (Mayall and Stewart, 2000; Mayall and OByrne, 2002).

ARTICLE IN PRESStroleumM. Mayall et al. / Marine and Pe830channel. Depending on the style, they have the potentialfor forming either high permeability zones (coarse sandsand conglomerates) or possible production barriers andbafes (mudclast conglomerates and shale-drapes). Of thethree types probably only the coarse sands and conglom-erates have the potential for being recognised on seismicdata. Therefore when modelling turbidite channels it isimportant to recognise the potential for critically differentreservoir properties at the base of channels.

4.2. Slumps and debris flows

Many channels contain slump and debris ow facies.These vary from a few centimetres to tens of metres thick.

Fig. 12. Basal Lag facies in channel ll (see Fig. 11). The basal lag may be repre

and (c) outcrop (mudclasts are present in the recessively weathered areas, exam

and (e) outcrop, (Brushy Canyon Fm, Texas), which can form a permeability ba

few metres thick. The conglomeratic basal lags are often acoustically hard. FiAco13beadmutrasup

sen

ple

rrie

g. 1Geology 23 (2006) 821841wide variety of processes are involved including internallyherent slides, slumps and incoherent debris ows (Fig.ad). Some of the facies are clearly seen on seismic to haveen derived locally by sliding and slumping from thejacent channel walls (Fig. 13d). However, it is likely thatch of the material has been derived by long distancensport from much further upslope. The potentiallyporting lines of evidence for this includes:

the debris ows may contain extraformational clastswhich are coarser than any other material in the sandyor conglomerate facies seen in the channel;some channels have such large volumes of slump/debris ows that it is hard to see how all of this

ted by coarse sands and gravels (a), mud clast conglomerates in (b) core

s arrowed, Pab Fm, Pakistan) or (d) shale by-pass drapes in (d) core,

r or bafe. The basal lag is generally from a few tens of centimetres to a

2c kindly supplied by Remi Eschard.

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Pematerial could have been derived from the local channelwalls.

Slumps and debris ows are common components ofturbidite channels studied in outcrop e.g. Clark andPickering (1996b), Eschard et al. (2003). Posamentier andKolla (2003) note that slumps and debris ows are mostcommon at the early stages of a lowstand sequence butmay also occur mid-cycle. Although they were discussingunchannelised mass transport complexes, this wouldconcur with our own observations that the slumps/debrisows commonly occur near the base of channel lls.Seismically the facies usually forms weak-moderate,

discordant to chaotic amplitude reectors. In some cases,these facies are mostly seismically opaque and can be

Fig. 13. Slumps and debris ows in a channel ll (see Fig. 11) are in part deriv

along the channel. Can comprise slumps (a and b), debris ows (c) or rotatioeum Geology 23 (2006) 821841 831difcult to distinguish from thick massive sands. This is animportant pitfall and is discussed later.In general, the slump/debris ow facies are composed of

muddy matrix and muddy sands to clean sands but withcomplex contorted geometries, and as such are generallynot effective reservoirs for oil. However, in gas reservoirsthey may contribute to production. This facies has a greatpotential for forming important permeability barriers orbafes during production.

4.3. Stacked high N:G channels

From a reservoir perspective, the most importantelement in the facies ll of a channel we call stacked highnet to gross channels (Fig. 14). This facies comprises

ed from the channel walls but also have undergone long-distance transport

nal slide blocks (d, arrowed).

ARTICLE IN PRESStrolM. Mayall et al. / Marine and Pe832stacking and amalgamation of a series of channels each ofwhich are typically 110m thick and 100500m wide. Ongood quality seismic these individual channels, or at leastsome lengths of them, can be resolved on amplitudeextraction maps. They are dominated by massive sandswith Ta and Tb turbidites (Fig. 14a). Thin mudclastconglomerates or coarse lags may mark the base of eachchannel. Some channels showing ning/thinning upwardsof beds and Tc, Tcd and hemipelagic shales may bepreserved at the top of the individual channel lls. Inoutcrops in particular, it can be seen that thickeramalgamated beds dominate the axis of the channels,while towards the margins of each individual channel moreshale beds were deposited and preserved resulting in thedominance of more thinly interbedded facies and lower netto gross (Fig. 14b) (Beaubouef, 2004; Beaubouef et al.,1999; Eschard et al., 2003; Campion et al., 2000; Gardneret al., 2003). In examples where there is focused stacking ofthese smaller channels within the larger erosional conne-ment, it is common to nd axis dominated and margin-dominated areas of the channel ll developed (Fig. 14c).

Fig. 14. High netgross stacked channels in a channel ll (see Fig. 11), are

interbedded sands and sales towards the margins (b). Outcrop picture (b) from

CMchannel margin (Beaubouef et al., 1999). Stacking of the sands may ge

upwards compaction features, arrowed (c and d).eum Geology 23 (2006) 821841This effect, combined with the contrast with the adjacentmudstones, often results in prominent differential compactionover the highest N:G parts of the channel ll. In somechannels, the differential compaction effect extends tens or evenhundreds of metres into the overlying sequence (Fig. 14c andd). In these cases, recognising this effect can be the simplest andmost effective approach to predicting good reservoir presenceand location. In other channels, focused stacking may notoccur and even in high N:G facies there may be no differentialcompaction effects to assist reservoir prediction.Many outcrop studies of turbidite channels focus on this

element of the channel ll sequence and there are manydetailed descriptions and illustrations of the range of faciesand architectural elements. These studies clearly demon-strate the heterogeneity patterns that can develop and thedistribution of potential barriers and bafes to uid ow(e.g. Campion et al., 2000; Clark and Pickering, 1996a, b;Cook et al., 1994; Cronin et al., 2000; Eschard et al., 2003;Gardner et al., 2003; Hickson and Lowe, 2002; May andWarme, 2000; Morris and Busby-Spera, 1990; Slatt, 2000;Slatt et al., 2000).

typically dominated by massive sands (a and b) but with more thinly

the Buena Vista outcrop Brushy Canyon Fm, Texas, CAchannel axis,

nerate well-dened axis with mounded/chaotic seismic facies and convex-

ARTICLE IN PRESStrolM. Mayall et al. / Marine and PeThe high net-to-gross stacked channel facies is clearly themost prolic and simplest reservoir facies within the largeerosional channels. Net to gross values are typically4070% with good connectivity, although heterogeneitiesoccur in the form of shales deposited and preserved at thetop of individual channels and more heterolithic facies atthe margins.In the subsurface, the biggest pitfall with this facies can

be in distinguishing it seismically from the slump/debrisow facies. When the N:G is high, there may be no internalreectors to resolve the individual channels. Only a top andbase reector may be present with the internal seismiccharacter being opaque or weak and discontinuous givingit a very similar seismic appearance to the slump/debrisow facies. Additionally, the slope/debris ow facies maygenerate a differential compaction effect through acombination of depositional topography and the morecohesive, less compactable mudstones in the debritescompared to adjacent mudstones. Resolving this issuemay not be easy, even with the best quality seismic andthere remains a risk in distinguishing between the best

Fig. 15. Sinuous channel levees as the nal ll of a channel (see Fig. 11). High

amplitude map). The interval is dominated by a narrow sinuous axis and thineum Geology 23 (2006) 821841 833(high N:G stacked channels) and worst (muddy debrites)facies.

4.4. Low N:G channel levees

In many of the large erosional channels, the nal elementin the ll comprises a highly sinuous leveed channel(Fig. 15a and b). This nal channel may often spill beyondthe original connement of the large erosional channel(Fig. 15a). In some cases, this may just be a thin (410mthick, 50100m wide) nal channel with poorly imagedlevees, which it can be argued, is just the topmost, andtherefore the most clearly imaged channel of the high N:Gstacked channel facies. However, in other cases the nalphase of the channel ll is a prominent channel-leveesystem with the channel up to 500m wide, a few tens ofmetres deep with prominent levees wedging away fromthe channel axis. In these larger examples the channel llsare predominantly muddy or low N:G and the leveesare dominated by patchy sands at the base and thinlyinterbedded sands and muds in the bulk of the levee

ly sinuous channel-levees often form the nal ll of the channels (a, RMS

bedded sands in the levees (b).

(Fig. 15a). Because it occurs at the top of the channel lls,this facies can occupy an important percentage of thehydrocarbon volume in the trap. However, the patchydistribution of the sands and the thin-bedded facies canmake this a difcult interval to develop.This nal phase of the channel ll has apparently not

been widely recognised in outcrop studies. Gardner andBorer (2000) and Gardner et al. (2003) recognise anunchannelised spill phase as the nal phase in the channelll models for the Brushy Canyon Formation outcrops butthis is not interpreted as a levee deposit.In most channels, shales and silts deposited by low-

density turbidites can also be an important part of thechannel ll. The shales were deposited during periods oftemporary channel abandonment presumably during the4th-/5th-order highstands or if the active coarse depositionwas diverted down a different erosionally conned channelon the slope. The shale deposition varies from lling most

of a channel to depositing only thin drapes. In some casesthe channels have no active turbidite deposition for a timesuch that calacareous, planktonic foraminifera dominatedshales may be deposited as a condensed zone.Most large erosional channels can be subdivided using

this broad four-fold facies scheme that breaks the grossreservoir section into reservoir and non-reservoir compo-nents (Fig. 11). Although most contain some volumes of allof the four facies, they also clearly represent an idealisedmodel. Overall low N:G erosional channel lls may containa basal lag and perhaps mostly muddy slumps and debritesor are lled largely by large volumes of mudstones as thechannel is abandoned. High net to gross channel lls aredominated by thick intervals of stacked channels with onlysmall volumes of debrite material. All variations in betweenexist (Fig. 16).Additionally and critically the ll of large 3rd-order

0.5 millions years. Incision of a smaller channel may vary

ARTICLE IN PRESS

Low N:G (0-10-20)

Channel lag small isolated (sinuous)channels

Moderate N:G (20-30-40)

Axial core concentratedin part of channel Highly layered fill

High N:G (40-50-60+)

Stacked channels throughout

- no compaction

- local compaction

- well defined compaction

M. Mayall et al. / Marine and Petroleum Geology 23 (2006) 821841834Fig. 16. Range of N:G ll in channels and associated geometries.Fig. 17. Repeated cutting and lling within a large 3rd-order channel. In thisfrom very moderate erosion of earlier deposited channel llto severe erosion and substantial removal of earlier llsediments. This process has three very important implica-tions for reservoir distribution and connectivity (Mayallerosional channels is rarely simple. Most have been re-occupied repeatedly in a history of repeated cutting andlling. The repeated cutting and lling of turbidite channelsis discussed below.

5. Repeated cutting and lling

In most cases, the large erosional 3rd-order channelsappear to be relatively long-lived features. The lls of thechannels have often been re-incised by erosion and then in-lled two, three or even four times by smaller 4/5th-orderchannels. Biostratigraphic control in some of the largeerosional channels indicates that they were conduits forsediment transport along the slope over periods of up toexample only modest erosion is observed at the base of each cut (yellow).

ARTICLE IN PRESStroleumanFig

1.

Fig

san

debM. Mayall et al. / Marine and Ped OByrne, 2002). These issues are illustrated ins. 1719.

In the case of extensive erosion, which is not unusual,earlier channel-ll deposits may be preserved only aserosional remnants scattered throughout the channel.Even with good quality seismic data this can makemapping of the resulting complex stratigraphy withinthe channel very difcult. With poor quality seismic datacorrelation of logs can become very perplexing.

Fig. 18. Example of complex repeated cut and

. 19. The large erosional 3rd-order channel is divided into a series of sma

dy channel of sequence 2 and is lled with muddy debris ows. As a result se

ris ow ll of sequence 3. Isochron scale from ca. 50m, purple to 0m, bro2.

3.

ll. I

ller

que

wn.Geology 23 (2006) 821841 835The facies at the base of each 4/5th-order inll sequenceis critical to the connectivity across the larger erosionalchannel. If these facies are composed of mudclastconglomerates or shale drapes they may result inbarriers or bafes within the reservoir.The inll of each 4/5th-order channel ll sequenceusually varies. If one channel ll is dominated by muddyslumps/debris ows the entire channel ll can act tocompartmentalise the reservoirs within the erosionalremnants of earlier channel lls. Additionally, such

nterpretation of erosional cuts in yellow.

4/5th-order channels (sequences 15). Sequence 3 partially erodes the

nce 2 comprises a series of erosional remnants separated by the muddy

channel lls can be difcult to distinguish within anotherwise sand-dominated ll, even with good qualityseismic due to the complex internal stratigraphy. Inthese circumstances, they can have an importantnegative and unanticipated impact on hydrocarbonvolumes.

The repeated cutting and lling is a feature of mostsubsurface examples in even moderate quality seismic data.In outcrops, this characteristic is harder to map on all butthe largest exposures, however excellent examples havebeen documented from a number of areas (e.g. Clark andPickering, 1996b; Eschard et al., 2003; Gardner et al.,2003).In our experience, repeated cutting and lling are a

common, extensive and important process within mostlarge 3rd-order erosional channels. Recognising, interpret-ing and mapping these features in as much detail aspossible is a crucial element, that must be undertaken earlyin the process of evaluating the large erosional channels.Such is the extent of the process that even if the seismic

does not allow direct observation of repeated erosion, theyare likely to be present. In these circumstances, it may beimportant to include the architecture conceptually as asensitivity in a reservoir model and may help in trying toexplain perplexing and inconsistent log correlation and/orbiostratigrahic dating within the channel ll.

6. Stacking patterns

In the above section, the characteristic of repeated cuttingand lling of 4/5th-order channels within the large 3rd-ordererosional channel was described. An additional and criticalfactor in determining reservoir distribution and effectiveexploitation of reserves is in the way the channels stack.A wide variety of stacking patterns can be developed

(Clark and Pickering, 1996a, b). Vertical stacking may beproduced by focusing of the channel cutting and llingevents leading to the pronounced differential compactiondescribed above. Lateral stacking is common and may takethe form of systematic stacking in one direction oralternating on either side of a pre-existing channel. Inpractice, an element of both vertical and lateral stacking isusually present although one form of stacking usuallypredominates.Additionally, it is quite usual for the stacking patterns to

vary over short distances along the length of a channel.Fig. 20 shows an example where four discrete segments ofstacking can be recognised over an 8 km length of channelall within a hydrocarbon eld. Fig. 21 illustrate otherexamples of changes in stacking pattern style over shortdistances along a channel. The cause of changes in stackingstyle can be difcult to recognise, but are probably relatedto local subtle variations in sea-oor topography and/orsubsidence.

ARTICLE IN PRESS

rde

S a

M. Mayall et al. / Marine and Petroleum Geology 23 (2006) 821841836Fig. 20. Wide range and rapid change in stacking pattern style of 4th/5th-o

Base of channel shown by yellow pick, palaeoow from NS. Map is an RMLine 1 mostly lateral stacking in different directions, line 2 strong vertical stack

in different directions.r channels over short distances within a large erosional 3rd-order channel.

mplitude extraction over a 30ms window in the middle of the channels ll.ing, line 3 lateral stacking in one direction, line 4 return to lateral stacking

ARTICLE IN PRESS

lar

dis

trolIn our experience, changes in stacking style are extremelycommon along the length of a channel, in fact they are tobe expected. Generally, a reservoir model based on one

Fig. 21. Dramatic change is stacking style of 4/5th-order channels within a

can result in dramatically different reservoir distribution patterns over short

same channel.

M. Mayall et al. / Marine and Pestyle of stacking may be completely inappropriate for largesegments of the reservoir.Recognising the stacking patterns within the channels

is also critical in designing the location and orientationof development wells (Mayall and OByrne, 2002).As discussed earlier, there is a risk that the faciesat the base of a channel may act as permeabilitybarriers or bafes. Development wells, both pro-ducers and injectors, need to be designed to mitigatethis risk by crossing as many potential barriers/bafesas possible and to connect the best reservoir facies.In examples where the stacking patterns changealong the structure this may require radically differentwell trajectories and azimuths to effectively exploit theresource.Critically this can potentially impact consideration

of a development concept (Mayall and OByrne, 2002)(Fig. 22). Developing a eld from a xed platform hasmany advantages of dry trees allowing easier access towells for workovers, etc. However, from a single xedplatform well designs may have a complex range oforientations to effectively exploit the reservoir. Thiscan lead to difcult and expensive wells and potentiallylimit data collection in the well. With a subsea develop-ment the more exible drill centre locations can beoptimised to allow optimum penetration of the reservoirwith simpler, cheaper wells. The relationship between faciesdistribution, stacking patterns and well design is a relation-ship that needs to be considered as early as possible in aproject.

ge erosional 3rd-order channel (yellow pick). Switching of the channel axis

tances along a channel. These two seismic lines are ca. 1 km apart along the

eum Geology 23 (2006) 821841 8377. Conclusions

Turbidite channel reservoirs often form highly complexreservoirs. A combination of highly variable facies andcomplex internal stratigraphy makes description andprediction of the reservoirs very difcult even with highquality seismic data. These effects essentially result in eachchannel being unique, and from a practical perspective,simple channel-ll models have limited value and applica-tion. However, within most channels there are a series ofrecurring features which, in analysing them, provides anapproach to understanding the distribution of reservoirfacies and heterogeneities within large (13 km wide), 3rd-order, erosionally-based channels.

7.1. Sinuosity

Most turbidite channels are variably sinuous. Thesinuosity of the channels is created by a number ofdifferent processes including erosion, lateral stacking,lateral accretion and sea-oor topography. The differentstyles of sinuosity can strongly effect the distribution ofreservoir facies.

7.2. Facies

The potential reserve facies which ll turbiditechannels can be grouped into four associations. Each of

ARTICLE IN PRESStroleum838thesei

Fig

uni

Fig

in c

toM. Mayall et al. / Marine and Pese can often be identied on even moderate qualitysmic data.

basal lags of coarse sand/conglomerates, mudclastconglomerates or shale drapes;

50m

1km

Mudstones Channel ma

Coarse chan

Stacked cha

Mudclast conglomeratesLevee deposits

Slump / Debris flows

Shales presestacked chan

. 23. Summary model showing the potential reservoir distribution and hete

que but can be interpreted by considering:

The sinuositythere may be a number of different causes

The four main faciesbasal lags, slumps, high N:G channels, channel leve

Repeated cutting and llingit is probably there, even if it cannot be ima

Stacking patternsrapid changes can be expected along the channel

. 22. Drilling from a xed location platform may result in development well

ompletion success and restrict data collection. The more exible location of

be drilled (b). Figures made by Ciaran OByrne.

rgin

nel

nne

rvene

rog

e

ged

s wi

muGeology 23 (2006) 821841slumps and debris ows which may be locally derivedfrom the collapse of channel walls or from long distancetransport;high netgross stacked channels form the best qualityreservoirs;

lags

l sands in axis

d inl sands

eneity patterns in a large 3rd-order erosional channel. Each channel is

.

th very complex trajectories (a). The complex designs may result in risk

ltiple drilling manifolds in a sub-sea scheme require less complex wells

Acknowledgements

ARTICLE IN PRESStrolBeadata, Niger Delta continental slope. American Association of

Petroleum Geologists Bulletin 89 (5), 627643.

Babonneau, N., Savoye, B., Cremer, M., Klein, B., 2002. Morphology and

architecture of the present canyon and channel system of the Zaire

deep-sea fan. Marine and Petroleum Geology 19, 445467.

Beaubouef, R.T., 2004. Deep-water leveed-channel complexes of the Cerro

Torro Formation, Upper Cretaceous, southern Chile. American

Association of Petroleum Geologists 88 (11), 14711500.

ubouef, R.T., Rossen, C., Zelt, F.B., Sullivan, M.D., Mohrig, D.C.,

Jennette, D.C., 1999. Deep-water sandstones, Brushy Canyon Forma-References

Abreu, V., Sullivan, M., Pirmez, C., Mohrig, D., 2003. Lateral accretion

packages (LAPs): an important reservoir element in deep water

sinuous channels. Marine and Petroleum Geology 20, 631648.

Adedayo, A.A., McHargue, T.R., Graham, S.A., 2005. Transient fan

architecture and depositional controls from near-surface 3-D seismicThe authors which to acknowledge the value of the manydiscussions with present and former colleagues, especiallyRichard Syms, Jonathon Henton, Ciaran OByrne, ArtDonovan. The ideas presented here have also grown fromnumerous discussions and debates with geoscientists frommany oil companies and universities around the world. Wealso acknowledge BP, Sonangol, Total, ExxonMobil,Statoil, Norsk Hyrdo and ENI for permission to presentseismic images. Proof reading by DJCM is much appre-ciated.7.4. Stacking patterns

Internal stacking patterns within the 3rd-order channelscan be highly variable even over short distances along thechannel length. The stacking patterns may stronglyinuence development well design.Although each channel is unique, Fig. 23 shows the type

of internal facies architecture, stratigraphy and hetero-geneity patterns that might typically be present in a largeerosionally based turbidite channel. low netgross sinuous channel levee caps the channel lland may spill beyond the original erosional conne-ment.

In addition to these facies, mudstone intervals, depositedduring high stand periods are often an importantcomponent of the channel ll.

7.3. Repeated cutting and filling

Periods of extensive re-incision at a 4/5th-order scale areusually present. This process results in very complexstratigraphy as earlier episodes of channel ll are preservedonly as erosional remnants.

M. Mayall et al. / Marine and Petion, West Texas: Field guide In: AAPG Hedberg Field Research

Conference.Beydoun, W., Kerdraon, Y., Lefeuvre, F., Lancelin, J.P., 2002. Benets of

a 3D HR survey for Girassol eld appraisal and development, Angola.

The Leading Edge 21, 11521155.

Brami, T.R., Tenney, C. M., Pirmez, C., Holman, K. L., Archie, C.,

Heeralal, S., Hannah, R., 2000. Late Pleistocene deepwater strati-

graphy and depositional processes offshore Trinidad and Tobago,

using 3D seismic data. In: Weimer, P., Slatt, R.M., Coleman, J.L.,

Rosen, N., Nelson, C.H., Bouma, A.H., Styzen, M., Lawrence, D.T.

(Eds.), Global Deep-Water Reservoirs: Gulf Coast Section SEPM

Foundation 20th Annual Bob F Perkins Research Conference,

pp. 402421.

Broucke, O., Temple, F., Rouby, D., Robin, C., Calassou, S., Nalpas, T.,

Guillocheau, F., 2004. The role of deformation processes on mud-

dominated turbiditic systems, Oligocene and Lower-Middle Miocene

of the Congo basin (West African margin). Marine and Petroleum

Geology 21, 327348.

Browne, G.H., Slatt, R.M., 2002. Outcrop and behind-outcrop character-

ization of a late-Miocene slope fan system, Mount Messenger

Formation, New Zealand. AAPG Bulletin 86, 841862.

Busby, C.J., Camacho, H., 1998. A new model for the MiocenePliocene

turbidite system at San Clemente, CA (abs.). AAPG Bulletin 82, 844.

Campion, K.M., Sprague, A.R., Mohrig, D., Lovell, R.W., Drzewiecki,

P.A., Sullivan, M.D., Ardill, J.A., Jensen, G.N., Sickafoose, D.K.,

2000. Outcrop expression of conned channel complexes. In: Weimer,

P., Slatt, R.M., Coleman, J.L., Rosen, N., Nelson, C.H., Bouma,

A.H., Styzen, M., Lawrence, D.T. (Eds.), Global Deep-Water

Reservoirs: Gulf Coast Section SEPM Foundation 20th Annual Bob

F Perkins Research Conference, pp. 127151.

Clark, J.D., Gardiner, A.R., 2000. Outcrop analogues for deep-water

channel and levee genetic units from the Gres dAnnot turbidite

systems, SE France. In: Weimer, P., Slatt, R.M., Coleman, J.L.,

Rosen, N., Nelson, C.H., Bouma, A.H., Styzen, M., Lawrence, D.T.

(Eds.), Global Deep-Water Reservoirs: Gulf Coast Section SEPM


pp. 175190.

Clark, J.D., Pickering, K.T., 1996a. Submarine Channels: Processes and

Architecture. Vallis Press, London, (231pp).

Clark, J.D., Pickering, K.T., 1996b. Architectural elements and

growth patterns of submarine channels: applications to Hydrocarbon

exploration. American Association of Petroleum Geologists 80 (2),

194221.

Clemenceau, G.R., Colbert, J., Edens, D., 2000. Production results from

levee overbank turbidite sands at Ram/Powell eld, deepwater Gulf of

Mexico. In: Weimer, P., Slatt, R.M., Coleman, J.L., Rosen, N.,

Nelson, C.H., Bouma, A.H., Styzen, M., Lawrence, D.T. (Eds.),

Global Deep-Water Reservoirs: Gulf Coast Section SEPM


pp. 241251.

Coleman, J.L., 2000. Reassessment of the Cerro Toro (Chile) sandstones

in view of channel-levee-overbank reservoir continuity issues. In:

Weimer, P. Slatt, R. M., Coleman Jr., J., Rosen, N. C., Nelson, H.,

Bouma, A. H., Styzen, M., Lawrence, D. T. (Eds.), Deepwater

Reservoirs of the World: Gulf Coast Section SEPM Foundation 20th

Annual Bob F Perkins Research Conference, pp. 252262.

Cook, T.W., Bouma, A.H., Chapin, M.A., Zhu, H., 1994. Facies

architecture and reservoir characterization of a submarine fan channel

complex, Jackfork Formation, Arkansas. In: Weimer, P., Bouma,

A.H., Perkins, B.F. (Eds.), Submarine Fans and Turbidite Systems:

Gulf Coast Section SEPM Foundation 15th Annual Research

Conference, pp. 6981.

Cronin, B.T., 1995. Structurally-controlled deep sea channel courses:

example from the Miocene of southeast Spain and the Alboran Sea,

southwest Mediteranean. In: Hartley, A.J., Prosser, D.J. (Eds.),

Characterisation of Deep Marine Clastic Sytems: Geological Society

Special Publcation No. 94, pp. 115135.

Cronin, B.T., Kidd, R.B., 1998. Heterogeneity and lithotype distribution

eum Geology 23 (2006) 821841 839in ancient deep-sea canyons: Point Lobos deep-sea canyon as a

reservoir analogue. Sedimentary Geology 115, 315349.

ARTICLE IN PRESStrolCronin, B.T., Hurst, A., Celik, H., Turkman, I., 2000. Superb exposures of

a channel levee and overbank complex in an ancient deep-water slope

environment. Sedimentary Geology 132, 205216.

Cronin, B.T., Hurst, A., Celik, H., 2002. Low Net:Gross canyon ll with

meandering deep water channel elements, Baskil, eastern Turkey

comparison with offshore West Africa. In: AAPG-SEPM Convention,

Houston, Abstract No. A3536.

Damuth, J.E., Kolla, V., Flood, R.D., Kowsmann, R.O., Monteiro, M.C.,

Gorini, M.A., Palma, J.J.C., Belderson, R.H., 1983. Distributary

channel meandering and bifurcation patterns on Amazon deep-sea fan

as revealed by long-range side-scan sonar (GLORIA). Geology 11,

9498.

Das, H.S., Imran, J., Pirmez, C., Mohrig, D., 2004. Numerical modeling

of ow and bed evolution in meandering submarine channels. Journal

of Geophysical Research 119, C10009.

Deptuck, M.E., Steffens, G.S., Barton, M., Pirmez, C., 2003. Architecture

and evolution of upper fan channel-belts on the Niger Delta slope and

in the Arabian Sea. Marine and Petroleum Geology 20, 649676.

DeVries, M.B., Lindholm, R.M., 1994. Internal architecture of a channel-

levee complex, Cerro Toro Formation, southern Chile. In: Weimer, P.,

Bouma, A.H., Perkins, B.F. (Eds.), Submarine Fans and Turbidite

Systems: Gulf Coast Section SEPM Foundation 15th Annual Research


Elliott, T., 2000. Depositional and stratigraphic architecture of a sand-

rich, channelized turbidite system: The Upper Carboniferous Ross

Sandstone, western Ireland. In: Weimer, P., Slatt, R.M., Coleman,

J.L., Rosen, N., Nelson, C.H., Bouma, A.H., Styzen, M., Lawrence,

D.T. (Eds.), Global Deep-Water Reservoirs: Gulf Coast Section

SEPM Foundation 20th Annual Bob F Perkins Research Conference,

pp. 342373.

Emmel, F.J., Curray, J.R., 1985. Bengal Fan, Indian Ocean. In: Bouma,

A.H., Normark, W.R., Barnes, N.F. (Eds.), Submarine Fans and

Related Turbidite Systems. Springer, New York, pp. 107112.

Eschard, R., Elbouy, E., Deschamps, R., Euzen, T., Ayub, A., 2003.

Downstream evolution of turbiditic channel complexes in the Pab

Range outcrops (Maastrichtian, Pakistan). Marine and Petroleum

Geology 20, 691710.

Fonnesu, F., 2003. 3D seismic images of a low sinuosity slope channel and

related depositional lobe (West Africa deep-offshore). Marine and

Petroleum Geology 20, 615629.

Fugitt, D.S., Herricks, G.J., Wise, M.R., Stelting, C.E., Schweller, W.J.,

2000. Production characteristics of sheet and channelized turbidite

reservoirs, Garden Banks 191, Gulf of Mexico, USA. In: Weimer, P.,

Slatt, R.M., Coleman, J.L., Rosen, N., Nelson, C.H., Bouma, A.H.,

Styzen, M., Lawrence, D.T. (Eds.), Global Deep-Water Reservoirs:

Gulf Coast Section SEPM Foundation 20th Annual Bob F Perkins

Research Conference, pp. 389401.

Gardner, M.H., Borer, J.M., 2000. Submarine channel architecture along

a slope to basin prole, Brushy Canyon Formation, west Texas. In:

Bouma, A.H., Stone, C.G. (Eds.), Fine-Grained Turbidite Systems:

AAPG Memoir 72 and SEPM Special Publication 68, pp. 195214.

Gardner, M.H., Borer, J.M., Melik, J.J., Mavilla, N., Dechesne, M.,

Wagerle, R.D., 2003. Stratigraphic process-response model for

submarine channels and related features from studies of Permian

Brushy Canyon outcrops, West Texas. Marine and Petroleum Geology

20, 757788.

Haughton, P.D.W., 2000. Evolving turbidite systems on a deforming basin

oor, Tabernas, SE. Spain. Sedimentology 47 (4), 497518.

Hickson, T.A., Lowe, D.R., 2002. Facies architecture of a submarine fan

channel-levee complex: the Juniper Ridge Conglomerate, Coalinga,

California. Sedimentology 49, 335362.

Humphreys, N.V., Williams, T.A., Monson, G.D., Blundell, L.C., 1999.

In: Technology Application as an Enabler for Rapid Development of

the Zaro Field, Equatorial Guinea: AAPG International Conference,

Extended Abstracts with Program, 246pp.

Johnson, S.D., Flint, S., Hinds, D., DeVille Wickens, H., 2001. Anatomy,

M. Mayall et al. / Marine and Pe840geometry and sequence stratigraphy of basin oor to slope turbidite

systems, Tanqua Karoo, South Africa. Sedimentology 48, 9871023.Kendrick, J., 2000. Turbidite reservoir architecture in the Gulf of

MexicoInsights from eld development. In: Weimer, P., Slatt,

R.M., Coleman, J.L., Rosen, N., Nelson, C.H., Bouma, A.H., Styzen,

M., Lawrence, D.T. (Eds.), Global Deep-Water Reservoirs: Gulf

Coast Section SEPM Foundation 20th Annual Bob F Perkins

Research Conference, pp. 450468.

Kenyon, N.H., Amir, A., Cramp, A., 1995. Geometry of the younger

sediment bodies of the Indus Fan. In: Pickering, K.T., Hiscott, R.N.,

Kenyon, N.H., Ricci Lucchi, F., Smith, R.D.A. (Eds.), Atlas of Deep

Water Environments: Architectural Style in Turbidite Systems. Chap-

man & Hall, London, pp. 8993.

Kirschner, R.H., Bouma, A.H., 2000. Characteristics of a distributary

channel-levee-overbank system, Tanqua Karoo. In: Bouma, A.H.,

Stone, C.G. (Eds.), Fine-Grained turbidite Systems, AAPGMemoir 72

and SEPM Special Publication No. 68, pp. 233244.

Kneller, B., 2003. The inuence of ow parameters on turbidite slope and

channel architecture. Marine and Petroleum Geology 20, 901910.

Kolla, V., Bourges, P., Urrity, J.M., Safa, P., 2001. Evolution of

deepwater tertiary sinuous channels offshore, Angola (West Africa)

and implications to reservoir architecture. AAPG Bulletin 85,

13731405.

Link, M.H., Stone, C.G., 1986. Jackfork Sandstone at the abandoned Big

Rock Quarry, North Little Rock, Arkansas. In: Stone, C.G., Haley,

B.R. (Eds.), Sedimentary and Igneous Rocks of the Ouachita

Mountains of Arkansas: Guidebook, Geological Society of America

Annual Meeting, San Antonio, 118pp.

Lomas, S.A., Cronin, B.T., Hartley, A.J., Duranti, D., Hurst, A., Mackay,

F., Clark, S.J., Kelly, S., 2000. Detailed characterisation of lateral

heterogeneities in exceptionally exposed sand-rich turbidite outcrops

from the Gres dAnnot, SE France: Stratal continuity and reservoir

simulation. In: Weimer, P., Slatt, R.M., Coleman, J.L., Rosen, N.,

Nelson, C.H., Bouma, A.H., Styzen, M., Lawrence, D.T. (Eds.),

Global Deep-Water Reservoirs: Gulf Coast Section SEPM Founda-

tion 20th Annual Bob F Perkins Research Conference, pp. 502514.

May, J.A., Warme, J.F., 2000. Bounding surfaces, lithologic variability,

and sandstone connectivity within submarine-canyon outcrops,

Eocene of San Diego, California. In: Weimer, P., Slatt, R.M.,

Coleman, J.L., Rosen, N., Nelson, C.H., Bouma, A.H., Styzen, M.,

Lawrence, D.T. (Eds.), Global Deep-Water Reservoirs: Gulf Coast

Section SEPM Foundation 20th Annual Bob F Perkins Research


Mayall, M., OByrne, C., 2002. In: Reservoir Prediction and Development

Challenges in Turbidite Slope Channels: OTC Conference Proceed-

ings, Contribution No. 14029.

Mayall, M., Stewart, I., 2000. The architecture of turbidite slope channels.

In: Weimer, P., Slatt, R.M., Coleman, J.L., Rosen, N., Nelson, C.H.,

Bouma, A.H., Styzen, M., Lawrence, D.T. (Eds.), Global Deep-Water

Reservoirs: Gulf Coast Section SEPM Foundation 20th Annual Bob F

Perkins Research Conference, pp. 578586.

Morris, W.R., Busby-Spera, C.J., 1988. Sedimentological evolution

of a submarine canyon in a forearc basin, Upper Cretaceous

Rosario Formation, San Carlos, Mexico. AAPG Bulletin 72,

717737.

Morris, W.R., Busby-Spera, C.J., 1990. A submarine fan valley-levee

complex in the Upper Cretaceous Rosario Formation: implication for

turbidite facies models. GSA Bulletin 102, 900914.

Mulder, T., Syvitski, J.P.M., Migeon, S., Faugeres, J.-C., Savoye, B.,

2003. Marine hyperpycnal ows: initiation, behavior and related

deposits: a review. Marine and Petroleum Geology 20, 861882.

Navarre, J.-C., Claude, D., Librelle, F., Safa, P., Villon, G., Keskes, N.,

2002. Deepwater turbidite system analysis, West Africa: sedimentary

model and implications for reservoir model construction. The Leading

Edge 21, 11321139.

Peakall, J., McCaffrey, W.D., Kneller, B., 2000. A process model for the

evolution, morphology and architecture of sinuous submarine

channels. Journal of Sedimentary Research 70, 434448.

eum Geology 23 (2006) 821841Pirmez, C., Imran, J., 2003. Reconstruction of turidity currents in Amazon

Channel. Marine and Petroleum Geology 20, 823850.

Pirmez, C., Beaubouef, R.T., Friedmann, S.J., 2000. Equilibrium prole

and baselevel in submarine channels: examples from Late Pleistocene

systems and implications for the architecture of deepwater reservoirs.

In: Weimer, P., Slatt, R.M., Coleman, J.L., Rosen, N., Nelson, C.H.,




Posamentier, H.W., 2003. Depositional elements associated with a basin

oor chanel-levee system: case study from the Gulf of Mexico. Marine

and Petroleum Geology 20, 677690.

Posamentier, H.W., Kolla, V., 2003. Seismic geomorphology and

stratigraphy of depositional elements in deep-water settings. Journal

of Sedimentary Research 73, 367388.

Posamentier, H.W., Meizarwin, P., Wisman, S., Plawman, T., 2000. Deep

water depositional systemsUltra-deep Makassar Strait, Indonesia.

In: Weimer, P., Sian, R.M., Coleman, J.L., Rosen, N., Nelson, C.H.,




Prather, B.F., 2003. Controls on reservoir distribution, architecture and

stratigraphic trapping in slope settings. Marine and Petroleum

Geology 20, 529545.

Prather, B.F., Booth, J.R., Steffens, G.S., Craig, PA., 1998. Classication,

lithologic calibration, and stratigraphic succession of seismic facies in

intraslope basins, deep-water Gulf of Mexico. AAPG Bulletin 82,

701728.

Coleman, J.L., Rosen, N., Nelson, C.H., Bouma, A.H., Styzen, M.,

Lawrence, D.T. (Eds.), Global Deep-Water Reservoirs: Gulf Coast

Section SEPM Foundation 20th Annual Bob F Perkins Research


Slatt, R.M., 2000. Why outcrop characterization of turbidite systems. In:

Bouma, A.H., Stone, C.G. (Eds.), Fine-Grained Turbidite Systems,

AAPG Memoir 72 and SEPM Special Publication 68, pp. 181186.

Slatt, R.M., Jordan, D.W., Davis, R.J., 1994. Interpreting formation

microscanner log images of Gulf of Mexico Pliocene turbidites by

comparison with Pennsylvanian turbidite outcrops, Arkansas. In:

Weimer, P., Bouma, A.H., Perkins, B.F. (Eds.), Submarine Fans and

Turbidite Systems: Gulf Coast Section SEPM Foundation 15th

Annual Research Conference, pp. 335348.

Slatt, R.M., Stone, C.G., Weimer, P., 2000. Characterization of slope and

basin facies tracts, Lower Pennsylvanian Jackfork Group, Arkansas,

with applications to deepwater (turbidite) reservoir management. In:

Weimer, P., Slatt, R.M., Coleman, J.L., Rosen, N., Nelson, C.H.,




Sprague, A.R., Sullivan, M.D., Campion, K.M., Jensen, G.N., Goulding,

F.J., Sickafoose, D.K., Jennette, D.C., 2002. In: The Physical

Stratigraphy of Deep-Water Stratal a Hierarchical Approach to the

Analysis of Genetically Related Stratigraphic Elements for Improved

Reservoir Prediction: AAPG Annual Meeting Abstracts, Houston,

Texas, pp. 1013.

ARTICLE IN PRESSM. Mayall et al. / Marine and Petroleum Geology 23 (2006) 821841 841architectural elements with reference to seismic resolution: Implica-

tions for reservoir prediction and modeling depositional systems. In:

Weimer, P., Sian, R.M., Coleman, J.L., Rosen, N., Nelson, C.H.,


Reservoirs: Gulf Coast Section SFPM Foundation 20th Annual Bob F


Samuel, A., Kneller, B., Raslan, S., Sharp, A., Parsons, C., 2003. Prolic

deep-marine slope channels of the Nile Delta, Egypt. AAPG Bulletin

87, 541560.

Sikkema, W., Wojcik, K.M., 2000. 3D visualization of turbidite systems,

Lower Congo Basin, offshore Angola. In: Weimer, P., Slatt, R.M.,the northern California margin. Journal Sedimentary Research 71 (2),

237245.

Walker, R.G., 1975. Nested submarine channels at San Clemente,

California. GSA Bulletin 86, 915924.

Weimer, P., Slatt, R.M., 2004. Petroleum Systems of deepwater settings.

SEG EAGE Distinguished Instructor Series No. 7.

Wonham, J.B., Jayr, S., Mougamba, R., Chuilon, P., 2000. 3D

sedimentary evolution of a canyon ll (lower Miocene-age) from the

Mandorove Formation, offshore Gabon. In: Stow, V.D.A., MayaIl,

M. (Eds.), Deep-Water Sedimentary Systems: New Models for The

21st Century. Pergamon, Oxford, pp. 175197.Prather, B.F., Keller, F.B., Chapin, M.A., 2000. Hierarchy of deep-water Spinell, G.A., Field, M.E., 2001. Evolution of continental slope gullies on

Turbidite channel reservoirs--Key elements in facies prediction and effective developmentIntroductionStratigraphic setting and terminologySinuosityInitial erosive baseLateral stackingLateral accretionSea-floor topography

FaciesBasal lagsSlumps and debris flowsStacked high N:G channelsLow N:G channel levees

Repeated cutting and fillingStacking patternsConclusionsSinuosityFaciesRepeated cutting and fillingStacking patterns

AcknowledgementsReferences

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May All 2006