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SPE 1615

Conceptun Abu Dh

Manhal Sirat, Operation (AD

Copyright 2012, Society

This paper was prepare

This paper was selecteeviewed by the Societyfficers, or members. Eeproduce in print is res

Abstract

A carbonate fiectonics. A neineaments repr

reveals the dev

Structural consconstraint. Whsedimentation a

In total, six frastructural modewith a basemenwhich pose sigfaults creating a

Significant impdefine new plafor the ongoing

Key words: Str

ntroduction

The X-Field is horst is boundeThe X-Field ismeasured from(Permian) at threcognized withapping of the y

The aim of thiStructure. This n 2008.

Numerous publa regional scaleand Alavi, 1996

544

ual Structhabi: ConSabry L. Mah

DCO), UAE; H

y of Petroleum Enginee

ed for presentation at t

d for presentation by ay of Petroleum EngineElectronic reproductionstricted to an abstract o

eld in Onshorew seismic attresenting posselopment mech

traints such ashereas timing and sequence s

acture sets havel shows that tnt strike slip fagmoidal map gandulations tha

plications of thys within the s

g and future dev

ructural concep

situated at theed by two longs a double plu

m Figure 2. Thhe bottom of thhin the stratigryounger units o

is paper is to conceptual syn

lications discuse (Glennie et a6; Schreurs &

tural Modnstraints hmoud and DHemin Koyi, U

ers

he Abu Dhabi Internati

an SPE program commeers and are subject ton, distribution, or storaof not more than 300 w

re Abu Dhabi tributes analyssible major andhanism of the m

lineaments lenof the struct

stratigraphic fra

ve been identifthe contractionault. At least twgeometry. Therat may define n

his study inclustudied structuvelopment plan

ptual model, Ca

e southern endgitudinal NE funging asymmee 3D seismic mhe section up raphy indicatinof the Late Cre

provide a connthesis is base

ssed the tectonal., 1973; BootImmenhauser,

del of an and Impl

Desdemona MUppsala Unive

ional Petroleum Exhibi

mittee following review o correction by the autage of any part of thiswords; illustrations may

is characterizesis has been cod minor faultsmajor structure

ngth, faults thrtural developmamework and t

fied including nal structure hawo major longire are numerounew minor play

ude better undure. In additionns for this field

arbonate hydro

d of an isolatedfaults and frometrical anticlinmapping reveato the Damma

ng an uplift, exhetaceous Forma

nceptual strucd on an in-hou

nic evolution ofte et al., 1990;1999; Searle a

Onshorelications

Magdalena Poersity, Swede

ition & Conference hel

of information containthor(s). The material ds paper without the wry not be copied. The ab

ed by its componducted to res. Based on the and associate

row and displament events rthus needs furt

the N75W, Nas been modifieitudinal faults bus transverse fys.

derstanding of n, the new idend and for other

ocarbon field, A

d structural ridm the north by ne with averagals carbonates am Fm (Eocenhumation and ations.

tural model ouse new seismic

f both onshore Robertson et

and Cox, 1999;

Carbona

opa, Abu Dhaben

d in Abu Dhabi, UAE,

ned in an abstract submdoes not necessarily reritten consent of the Sbstract must contain co

mplicated structeveal the struchis analysis, a ed faults.

acements are strepresents a cther study.

N45W, NS, EWed as a giant pbound the strufaults linking

f the regional ntified fracturefields in the re

Abu Dhabi

dge (north-easta sinistral N7

ge length of 4dominating lit

ne) at the top (erosion at Sim

f a carbonate c attributes ana

and offshore oal., 1990; Bey; Immenhauser

ate Hydro

bi Company f

11–14 November 2012

mitted by the author(s)eflect any position of tSociety of Petroleum Eonspicuous acknowled

tural setting, wctural style, anconceptual m

trongly related challenge and

W, NE-SW andpositive floweructure parallel tand/or cross c

structural geole system providegion with sim

t oriented base5W strike-slip1 km and avethological units(Fig. 2). A ma

msima level (Up

hydrocarbon alysis of a 3D

of Abu Dhabi aydoun et al., 19r et al., 2000; Z

ocarbon F

for Onshore O

2.

). Contents of the papehe Society of PetroleuEngineers is prohibitedgment of SPE copyrig

which involvesnd to identify odel is presen

to the seismicneeds to be

d N70E. The Cr structure-like to its fold axis

cutting those lo

logy of Abu Ddes essential in

milar structural

ement horst, Fp fault (the Najerage width ofs from the Preajor unconformpper Cretaceou

field called hseismic data se

and the forelan992; Edgal, 19Zeigler, 2001; H

Field

Oil

er have not been um Engineers, its ed. Permission to ght.

s basement significant

nted, which

c resolution linked to

Conceptual associated

(NE-SW), ongitudinal

Dhabi, and nformation settings.

Fig. 1). The jd system). f 13 km as e Khuff Fm mity can be us) with on

here the X-et acquired

nd basin on 992; Talbot Hessami et

2

aa

F

Tcama Thsdrwth TminNCub IthSthFuW

2

al., 2001; Al-Laal., 2006; Ruba

Fig. 1. Structmap of Asituated abounded West, and

The mechanismcould only reacappealing hypomodification ofand vertically, t

The X-structurehave a first ordsection taken adips of the two ranging from 3wider variationhe fold geomet

The width andmeasurements nflection point

Nahr Umr (AlbCretaceous). Thupwards too. Fbecause of cove

In Table 1, wehese measurem

Simsima Formahe basin was u

Fm level to ca uncertainty of With the curren

azki et al., 200an et al., 2007;

tural elemenAbu Dhabi sat one isolated

by NE faultsd by a N75W

m of the structuch down to Preothesis that invf the basementthe mechanical

e length, widthder approximatat the southerne

limbs (NW an.5°-26° for the

ns in dip than thtry part of the t

d length of thwere also che

t of the fold (Tbian), i.e. it wihe variations in

From the time serage limitation

e present the vaments vary on ation, there is auplifted, exhum

3,500 ft at Nathe seismic dent available dat

02; Johnson et Sirat et al., 200

nts inferred hows that thd basement hs from the Efault from the

ural developme-Khuff Fm (Pevolves basemet inversion tectl layering and

h, amplitude antion of these veast central parnd SE) of the Xe NW limb comhe SE limb. Thtable.

he X-structureecked from the

Table 1). Theseidens upwards n lengths rangeslice map in Fn of the seismi

ariations in foldifferent cros

an inconsistencmed, eroded anahr Umr Fm (Mepths may rangta, we conclud

al., 2002a&b &07a&b; Ali et a

from gravityhe X-Field ishigh, which isEast and thee north.

ent of this fieldermian). Howeent inversion tetonic hypotheson lineament in

nd dip angles ovariations, we mrt of the X-stru

X-Structure varmpared to a ranherefore the num

e also varies,e time slices fe variations ran

(Figs. 2 & 3)e from 33 kmigure 2, it is oic data.

ld amplitudes ss-sections depcy between the

nd refolded in aMiddle Cretacge between ±2e here that this

& 2005; Melvial, 2008 & 200

y s s e

Fig. 2. S

anticindiccrosswideuncoMaa

d is still uncertver, Johnson eectonics of deesis emphasizingnterpretation.

of its two limbmeasured theseucture, and whry between 3.5

nge of 4° to 15°mbers in Table

as measured for each of thnge from 12.3 K. However, theat Marrat Fm

obvious that th

as estimated frpending on thee upper and lowa later stage. T

ceous) and ca 15 ft in the cres structure is di

ille et al., 200409; Faqira et al

Seismic crosscline. The bcates the poss-section sh

ening of the onformity at astrichtian).

tain especially et al., (2002 andep-seated Protg on the struct

s vary significe attributes froherein the deep5°–15° with dep° in the SE lime 1 are only th

along the samhose reflectorsKm at Marrat Fe width decreato 44 km at Si

he length at Kh

from the seismie inflection power reflecors dThese amplitud1,300 ft at Simstal parts, wheirectly related t

4; Edwards et al., 2009; Fourn

s-section acralck line maition of the prhows key

structure upthe Simsima

with the lack d 2005) presenterozoic rifts. Wtural geometry

cantly (Table 1om Figure 2, wpest well had bpth. Dips also

mb (Fig. 3), whee average mea

me cross-sectisuch that it h

Fm (Early Juraases to 13.7 kmimsima indicathuff Fm is long

ic cross-sectionoints of each hdue to the regiodes range betwmsima Fm leveereas it may reto the activity

S

al., 2005a&b; Fnier et al., 2011

ross fold axisap in the lerofile, while threflectors. Npward and t

a (Upper Cre

of deep seisminted a comprehWe present he

y variations bo

1 and Figs. 2, which is a seisbeen drilled. Tvary within eaere the NW lim

asurements as in

ion in Figurehas been takenassic) to 14.4 Km at Simsima Fting an increasger but cannot

n of Figure 2.horizon. Furtheonal unconform

ween ca 4,350 fel (Table 1, Feach ±50 ft at of basement fa

SPE 161544

Filbrandt et ).

of the X-eft corner he seismic Note the the major

eataceous/

ic data that hensive and ere a slight th laterally

3 & 4). To smic cross-

The average ach horizon mb exhibits ndicated in

e 2. These n from the Km wide at Fm (Upper e of length be verifed

. However, ermore, for mity, where ft at Marrat

Fig. 2). The the flanks.

ault(s). It is

S

nb T

S Mfclf SSshhimh WFtothed Cinlaoincf

SPE 161544

not possible to both dip and str

Table 1: Sum

Seismic attrib

Most of the larfaults of differecharacteristics evels, deeper s

folded sedimen

Seismic attribuSeismic attribuseismic attributhave been genhorizons were mproved much

help better und

We used here sFigure 3 can beo recognize a fhe fault plane,

evolution of thdepth horizons

Coherence and n waveform shateral changes

of discontinuityndicate faults

continuity betwformation. It ca

Arab/ U. Jurassic

Formation

Khuff/ Permian

Marrat/ L. Jurassic

Thamama F/ L. Cretaceous

Thamama B/ L. Cretaceous

Nahr Umr/ M. Cretaceous

Simsima/ U. Cretaceous

Arab/ U. Jurassic

Formation

Khuff/ Permian

Marrat/ L. Jurassic

Thamama F/ L. Cretaceous

Thamama B/ L. Cretaceous

Nahr Umr/ M. Cretaceous

Simsima/ U. Cretaceous

decide the truerike-slip (i.e. o

mmary of struc

butes analys

rge onshore fieent orientationscan be summastructures are n

ntary cover and

utes can be velute analysis helptes such as curv

nerated to reveanalyzed as w

h of the noise herstanding the

several seismicest describe thefault is to take , with their po

he X-Sructure bto reveal the m

other edge-dethape. Seismic ain seismic ima

y. Geologicallyand/or fractu

ween seismic tran also be used

34

Structure length (km)

33

33

42s

42s

43

44

34

Structure length (km)

33

33

42s

42s

43

44

e nature of the oblique slip).

ctural geomet

sis

elds are surveys. We have recarized. While tnot imaged at

d fault developm

locity, amplitups to enhance vature, varianc

eal the structurwell. Comparedhas been removdevelopment m

c profiles both e fold geometra seismic crosssible throws. both laterally a

map geometry e

tection attributattributes such ages. Their moy, highly coher

ures in the strraces in a spec

d to see faults, c

14.2

Structure width (km)

14

13.4

13.5

14.5

14

14

14.2

Structure width (km)

14

13.4

13.5

14.5

14

14

basement activ

try attributes

yed by moderncently started athe 3D seismiall. According

ment is what w

ude, frequencyinformation th

ce, coherence, aral configuratiod with the prevved, but multipmechanicsm of

perpendicular ry in the NE diss-section perpFurther, sever

and vertically evolution of th

tes measure theas amplitude,

ost important usrent seismic daata regardlesscified window channels or oth

4300

Structure amplitude

(ft)

4400

4350

4100

13800

3500

1300

α

4300

Structure amplitude

(ft)

4400

4350

4100

13800

3500

1300

α

vity, which can

n 3D seismic danalyzing the nc data providegly the nature

we try to concep

y, or rate of chhat might be subamplitude and on of the X-fivious seismic ples still havingf the X-structur

at, and parallerection. They c

pendicularly to ral attributes mwith time (Fig

he X-Structure w

e waveform simfrequency andse is to define aata indicate lat

of their oriealong a picked

her discontinuo

13.515

1511

1413

12714

11.511.5

10.59.5

43.5

αSE°αNW°

13.515

1511

1413

12714

11.511.5

10.59.5

43.5

αSE°αNW°

n be dip-slip (i

data, which shonature of these es unprecedentof these deep ptually model

hange of any oubtle in traditio

edge detectionfield in 3D. Se

data acquired g a great impacre with time.

el to, the fold acan also revealthe fault strike

maps in 2D andgs. 5-9). Six cwith time (Fig

milarity or contd dip azimuth ea local reflectoterally continu

entation. The cd horizon, canous features.

FoldFold

inversion), strik

ow that the fiefaults in detailted structural dstructures andin this paper.

of these with rnal seismic an

n, and attributeeismic time-sli

in 1999, the ct. The interpr

axis of the X-Sl the longitudine, which helpsd 3D have bee

coherence mapg. 5).

ntinuity and theenhance the visor upon which uous lithologiescoherence attr

n be used to m

d Geometryd Geometry

ke-slip or com

elds are cut byl where severaldetail down tod their relation

respect to timealysis. Therefo

es maps at diffeices and attribquality was sietation of these

Structure (Figsnal faults as th

s revealing the en prepared to

ps were taken a

ey highlight locsual appearancwe estimate sos and abrupt chribute that me

map the lateral

3

mbination of

y numerous l important

o Mesozoic nship to the

e or space. ore, several erent levels butes along ignificantly e attributes

s. 3 and 4). he best way

true dip of o reveal the at different

cal changes e of abrupt

ome degree hanges can easures the extent of a

4

CanRwhu

F

F Dc

4

Curvature attriband Edge detecnoise reductionRMS amplitudewere used to dehelp detecting used to detect d

Fig. 3. A comaxis, frombounding

Faults and fr

Different seismcoherence, curv

bute was also ction attributesn, and can perfoe maps (Fig. 8etect lineamenfractures on 2

different lineam

mposite picturm the SW to th

the structure

actures

mic cross-sectiovature, amplitu

used to reveals can estimate orm best in are

8), which compnts on numerouD-surfaces at

ments, which ca

re for nine seihe NE plunge, the variation

ons and time sude, dip and ed

l subseismic fra local varianc

eas of high verpute the Root Mus 3D-surfacesdifferent depthan be interpret

ismic cross-sees. Note the vn in structural

lices were chodge detection a

ractures that arce in the seismrtical angle fauMean Squares

of different dehs of the X-Stred as fault sets

ections acrosvariations in dstyle of the a

osen at differenattributes. Thes

re usually assomic wave-signaults as the case

on instantaneoepths of the Xtructure. Finalls of different or

ss the X-Strucdip of the antanticline at dif

nt depths fromse attributes we

ociated with foal, with optionhere with the X

ous amplitude o-Structure. Thely, several seisrientations (Fig

cture and alonticline limbs, fferent part of

m Upper Permiaere used to ide

S

olding (Fig. 6)nal vertical smoX-Structure (Fover a specifiee variance attrsmic attribute mg. 9).

ng the NE orithe traces of f the structure

an to Tertiary entify various l

SPE 161544

). Variance oothing for

Fig. 7). The ed window, ibute maps maps were

ented fold the faults

e.

time using lineaments,

S

wSslabm(so

F

Wsrass Tmcthind C BvrA(dth

SPE 161544

which can be fSW and N70E.several time slaterally while

be seen in bothmost of these f(Figs. 5 & 7).stepovers (resuoriented cross-s

Fig. 4. A comSE directi

While Johnsonsets, the occurrreactivated andappears in all hsuch as the NSsections (Figs.

The most signimore competencrucial to explahat cannot be nterrupted by

different mecha

Conceptual s

Based on the avertically, we iregimes througAbu Dhabi as (Carboniferousdefined N-S arhe deposition

faults and subs. The NE-SW ices, representextend with d

h map view anfaults show bra. Some of the

ulting in a slighsections (Figs.

mposite picturon reveals br

n et al., (2002) rence and bran

d twisted to dehydrocarbon fiS, N70E and E3, 8 & 9).

ficant faulting nt units the fauain the branchiwell recognizefew horizons oanical layers sh

structural mo

analysis and inintroduce a cohout the geolobeing part of time), where mches, except foof early Khuf

eismic fracturefault set, whicts the longitudepth. Faults of

nd cross sectionanching, where relays betwee

ht pop-up struc4A–D), where

re for four seiroad humps a

described thenching of the Nvelop the N45

ields of Abu DEW can be rec

is seen in the ult throws tending of some ofed in various sof less compethould be consid

odel

nterpretation onceptual modegic time.

f the Arabian much of the olor those troughff during the M

es. Six fracturech can be recogdinal faults parf this set are sen, with often fe the multiple en these fault

cture) or release several andul

smic cross-seand other pos

two en echeloN75W fault se

5W fault set. TDhabi, whereascognized on di

apparently mod to diminish af these longituseismic cross-stent or more dudered.

of these seismiel for the deve

Platform and lder Paleozoic hs, which wereMiddle Permia

e sets can be idgnized in manyrallel to the folegmented bothfew kilometersintersections (segments are

ing stepovers (lations like stru

ections takensibly isolated

on strike-slip fet might be in

This needs to b the N45W setifferent time s

ore brittle Lowand die out in ludinal (NE) fausections. Furthuctile Formatio

ic attributes, aelopment mech

Foreland Basiplatform succe

e filled by the ean times occur

dentified incluy of the cross-ld axis, which

h horizontally as long (Figs. 3(their traces) we usually well (creating a smauctures can be

n parallel to th mounds.

faults (N75W nterpreted as thbe studied furtht appears in so

slices but are d

wer Cretaceous less competentults (Figs. 5 &hermore, when ons such as N

and structural ghanism of the

in has been upession was upleroded materia

rred. The seism

uding the N75W-sections acrosh bound the twand vertically, , 6, 7, 8 & 9).

with the 2D surimaged and c

all graben). Threcognized.

he fold axis, a

and N45W) ahe older fractuher, especiallyome of them. Odifficult to be

carbonate, wht rock. The me

& 7) and the bethe dominant

ahr Umr, Fiqa

geometry variX-Structure w

plifted during lifted, exhumeal. Peneplanatimic reverse fau

W, N45W, NSss the X-anticliwo flanks of th

where segmen. On different rface can be ccan be either his can be seen

and from the N

s two possibleure set, which y that the N75WOther minor frrecognized in

here above andechanical layered bounded liklimestones su

a and Um Radh

ations both latwith its causativ

the Hercyniand and eroded aion followed, aults images in

5

, EW, NE-ine, and on

he structure ntation can time-slices lrealy seen restraining

n in the NE

NW to the

e conjugate have been

W fault set racture sets

n the cross-

d below the ring can be ke fractures uccession is homa Fms,

terally and ve tectonic

n Orogeny along well-after which n Paleozoic

6

sr

F

IAdSAeoc2 AewHbeth

6

strata are direcrelated to the P

Fig. 5. A comStructure caused bysigmoidal

In Late CretaceArabian platfordirection. This Structural trapsAbu Dhabi waepisodic structobduction of opcompression an2002).

As Plate motioevents have conwith the NE dirHacker et al., 1believe that thiexisting NE orihis modificatio

ctly linked to Han-African bas

mposite pictuand intersec

y the intersecshape of the

eous, a second rm, and causehas also resul

s in Abu Dhabs in the forelantural growth. Iphiolites in Omnd/or transpres

on vectors andntinued structurection during 996; Warrak, s gradual shiftiented antiformon is the reacti

Hercynian strusement grain (N

ure for six cocting these sctions of these X-structure i

major Phaneroed the major stted in the obdu

bi grew synchrnd of the deveIn all cases thman points to asion at baseme

d velocities unduring the regionthe Zagros oro1996; Miller ett of the maximu

m structures, whivation of the p

uctures, which Nicholson, 200

oherence masurfaces at de branching fan deeper part

ozoic comprestructuration ofuction of the S

ronously with teloping orogenhe synchronicia genetic relatient levels, prop

derwent majorn with dominaogeny from Mit al., 1999; Noum compressiohich have origipre-existing fau

root in deepe02 and Johnson

aps show theifferent depthaults with thet indicating po

sional event wf Abu Dhabi hSemail and Mathe Late Creta

ny and underwity of Late Conship betwee

pagating from t

r changes nearnt E-W directiocene to Prese

oweir, 2000; Saon direction froinally developeults (N75W) a

er structures ann et. al., 2002).

e traces of thhs (in mili see 2D surface (ossible NW o

with dominant Ehydrocarbon fiasira ophiolitesaceous orogeni

went compressioCretaceous struen the two. Thethe Oman Mou

r the Arabian ion during the ent (e.g. Pattonattarzadeh, et arom EWE to Eed during the Us shear and mo

nd can reasona

he NE faults econds). No(clearly seen

oriented fault.

ESE compressifields with doms of Oman (e.gic and Plate boon during oph

uctural growtherefore structuruntains into the

continental mEocene and M

n & O’Connor, al., 2002 and S-W to finally NUpper Cretaceoost likely dextr

S

ably be interpr

that boundinote the multipon D-F). Not

ion direction aminant ESE cog. Filbrandt et oundary events

hiolite emplaceh in Abu Dhabral growth wase foreland (Joh

margin, the comMiocene times,

1988; Boote eirat et al., 2007NE has modifious. The manifral strike-slip f

SPE 161544

reted to be

ng the X-ple traces te also the

affected the ompression al., 2006).

s in Oman. ment, with bi and the s driven by

hnson et al.,

mpressional and finally

et al., 1990; 7a&b). We ied the pre-festation of faults, with

S

psnC TanNcthebws

F

F

Tsth3nlicd(Athhvth

SPE 161544

possible propagstrata when thenew generationCretaceous carb

The variations anticline duringnecessity of theN75W or NE scross-sections that the X-fiel

especially in thbounded NE fawhich intersectslice and vertic

Fig. 6. Curvaseismic cbe showncross sec

Fig. 7. A comfault tracebetween segmenta

The X-anticlinestructure is asyhe NE along th

3°-5°, i.e. the fnortheast (Fig. imb by ca 4°, i

could be used dipping angles (Table 1). HowAlbian in Fig. 2hat are taken a

horizons has bvolumetric of the structure of

gation to the oe maximum prin of fracture sbonates.

in the width, g the Simsimae presence of atrike-slip faulttaken along thed has develop

he central part aults can be clet with differenally on differen

ature attributcube. Many Nn on the top stion.

mposite pictures intersectinthese segm

ation too.

e is not a cylinymmetric in prohe fold axis. Afold verges to t

3F) shows thi.e. the fold veto deduce the between the

wever, within 2 and Figs. 3C

across the fold een shifted eithe potential hy

f fraction of a d

overlying sedimincipal stress shsystems in the

length and dipa Fm (Campanactive deep-seas that link to the fold axis fromped as a giantof the X-antic

early seen fromnt time-slices, hnt time slices.

te at top SNE fold relateurface of Sim

re for four seisng different 3

ments. These

ndrical fold, noofile, i.e. its ve

A profile in the the SE (Fig. 3at the asymmerges northeastwkinematics of SE and NW lthe same limb

C, D & E), andaxis from SW

ther to the NWydrocarbon in pdegree to the N

mentary coverhifted in anticlMesozoic stra

pping angle (Tnian-Maastrichated faulting duhe horst structum the southwet flower-like sline, which is

m Figures 5, 7 have revealed

Simsima withed faults can

msima and the

smic attribute3D surfaces.

e faults trace

ot only beacsueergence changsouth shows thA). However,

etry has changwards (Figs. 3D

f the basement limbs range frbs, the dippingd for Late Juras

towards the NW or SE directi

place. Further,NW, which can

r. Or by the dlockwise directata (e.g. Sirat

Table 1, Figs. htian times) toguring the strucure of the basemestern plunge tostructure assocusually assum& 9. Furthermsegementation

h n e

e (variance) m

Note the sees change s

e it plunges in es. This asymmhat the southeaa profile in th

ged; the northwD-F). This flipfault, which c

rom 5°-10° on angles vary w

ssic from 7° (FNE of the X-ant

ion giving rise, the cross-sectbe attributed t

development oftions with timeet al., 2007a&

3 & 4), of thgether with itsctural growth. ment (Fig. 1). o the northeastciated with tw

med in the literamore, as shownn and branchin

maps at differeegmentation shape and

both directionmetry, switcheastern limb is she center part owestern limb isp in the vergencreated this str

n average in thwithin the samFig. 3A) to 14°ticline. Conseqe to different ations in Figureto the same bas

f new fracturee. This is suppo&b), which ar

he maximum-res sigmoidal shThese deep-seFigure 3, whi

tern plunge of wo deep seatedature as of cyln in Figures 5 ng both horizo

ent depths shof these fauwidth vertica

ns along its stries polarity as wsteeper than itsof the X-anticls dipping steep

nce of the X-anructure. Generhe southeastern

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SPE 161544

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SPE 161544 9

from Mauddud/ Albian time. This is quite different from other hydrocarbon fields of Abu Dhabi, although they all share the great influence of the deep-seated faults of the beasement. One of the most significant implications for the exploration is the existence of several minor folds along and at the vicinity of the fold axis, where the X-Structure appears to have at least two humps like with a saddle in between. These might represent two crests for hydrocarbon accumulations, which consequently impact the field development plan. Along strike of the structure, both the flanks and the crest of the X-anticline show andulations (gentle folding) implying relatively complex geometry, which would have a direct impact on hydrocarbon accumulation and exploration targets. Other implication is related to these six fracture sets with their flow properties. The shift of crestal part of each of the horizons to the NW or SE direction has yielded different amplitudes hence affect the volumetric of the potential hydrocarbon in place. The reservoirs flow behavior is highly affected by the NE longitudinal faults, which are most likely held opened and act as conduits, as they are parallel to the current regional maximum principal stress. Other fracture sets can significantly act as matrix enhacement features especially where they are likely bed-bounded fractures. The geomechanical issues related to fracture reactivation and cap rock integrity especially for competent layers is another implication. Hence, development scheme should take into account fractures reactivation potential at the vicinity of the injecting wells, especially when the injection rate exceeds the fracture surface roughness/ cohesion, hence fault slip or fractures become open, which may result in short water-cut. Acknowledgement: The Authors thank both ADCO and ADNOC to allow using and publishing the data. HK acknowledges financial support from the Swedish Research Council. References: Ali, M.Y., M. Sirat and J. Small (2009). Integrated gravity and seismic investigation over the Jabal Hafit structure:

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