SPE 29318

soclstYof PetrdelJnEndneera

Gas Fields Development h MalaysiaChen Kah Seong*, DannrisHusain* and Abdul Hamid Abdul Karim, Exploration &Production Sector, PETRONAS● SPE Membere

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ABSTRACT

This paper is a review of the gas fields development inMalaysia. The major subsurface engineeringconsiderations for gas development inctude drivemechanism determination, well requirement, completionstrategies, well deliverabiiiies, recovery factor andresewoir surveillance requirements. For surfaceengineering, the major considerations include offshorefacilities funtilon, platform con~uration and sequenceand process and compression requirements. The resultof the review is the summa~ of some of the differencesin gas fields development to date.

INTRODUCTION

The first gas field development in Malaysia started in1982 when E-1 1 field, located offshore Sarewak, wasdeveloped. In the following years, four more gas fieldsnamely Duyong, Jemeh, F-23 and F-8 were developed.The Duyong and Jemeh gas fields are located ofihorePeninsular Malaysia while E-1 1, F-23 and F-8 fields arelocated offshore Sarawak (Figure 1). The fields areoperated by PETRONAS Carigali Sendirian Berhad(PCSB), ESSO Production Malaysia Inc. (EPMI) andSarawak SHELL Berhad (SSB), all are the PSContractors to PETRONAS, the national oil company.

!n Peninsular Malaysia, the first development statied in1984 when Duyong field was developed by PCSB toprovide the necessaty offshore infrastructure forA-. -1-.. --..4 ,.s“*. GalA. n*ka.a Dmnim.,,lel@\4.3tm*.eiBUcwcluplllutll UI ~aa 11-IU= Ultaf IIA G r -1 ##lKlurnl # 8aray -#a.

Referencesand illustrationsat end of paper

W~h the increasing demand for gas prompted by theonshore pipeline network installation by PETRONAS tofuel the power and industrial sector, sales from Jemeh,EPMI’s first gas platform, was initiated in 1991. Gasdemand is projected to continue to grow in the nearfuture. To meet this growth, EPMI will develop anotherfield, namely Lawit, for production in 1997. In addition,two gas resenmim in existing producing oil fields werealso developed in 1984. However, their development willnot be discussed here.

In Sarawak, E-11, being the closest to shore, was thefirst gas field developed by SSB. Delivery of gas toshore commenced in 1982: Shortly thereafter, in 1983the second gas field F-23, came onstream. The thid andthe largest gas field, F-8, started production in 1987.Produced gas offshore Sarawak is delivered to LquefiedNatural Gas (LNG) plant and fertilizer plant. A smallportion was used for power generation. Another LNGproject is currently under construction and willcommence operation in 1995. Development of gas fieldsdedicated for the second LNG project is currently inprogress.

This paper discusses the major subsurface and surfaceengineering considerations for gas fields development inMalaysia. It will also outline some of the differences ingas fields development to-date.

GEOLOGY OF PRODUCING FIELDS

In Peninsular Malaysia, hydrocarbon accumulations arefound in the Upper Oliiocene - Upper Miocenealluvial-coastal plain elastics. Duyong field, the first tobe developed offshore Peninsular Malaysia, is a large

549

2 Gas Fields Development In Malaysia SPE 029318

asymmetrical anticlinal structure elongated in the eastwest direction. The main reservoir is interpreted to be ashorefacsdbarrier bar deposit. Jemehl f~ld is a largewest-notthwest to east-southeast trending anticline. Thegas bearing reservoirs are interpretad to have beendeposited in a lower coastal plain environment and aremostlytiial with some deltaic deposits.

The characteristic geological features of the CentralLuconia Province offshore Sarawak, which forms theouter half of the 200- 300 km wide Central SarawakSh5~, swn c.mhnnatp reefniri huiklyos of the Middle“, “ -, ””,,”.- , ------ ----- ~Miocene age. Stmcturally, the fiekts can be broadlydivided intotwo types :-

pinnacle carbonate build-up - steep sided andconical, developed where higher rates of subsidence

higher c!es?ic ~~pJ! ~~ RQ! ~!!~~ rn~;~~andhxcarbonate buildupsand buildoute.g. El 1.

platform carbonate buiidup - large, high-relief,steepflanked and flat-topped may cover 100 kmzareally and 1000 m thick e.g. F23 and F6,

The carbonate sequence comprises mainly limestonewitii minor amounts of doiomite beneath tiie mast.Stratigraphically, the fields can be groupad as carbonatebuild-up encased in shales and siliclastics.

MAJOR SUBSURFACE ENGINEERINGCONSIDERATIONS

Drive Mechanism

A key pail in the preparation of a gas development planis the determination of the reservoir drive mechanism.Since the gas reservoirs have associated aquifers, it isnecessaty to evaluate the extent and impact of aquiferactkity on gas production and recovery. However, thed.a.dh n~ +h an, dfar e nnnt ha Aetnrminarl hef(i~ naLIml&jLIl WI Llle asr”,,.a Us,,,,”. ““ “ .“, ,,,,.. ”” “---- - -

development commences. Usually, during predevelopment stage, the strength of aquifer is based ongeologist opinion, based on considerations of reservoirqualiiy and continuity in terms of regional geology. Gasresemoir producing under the influence of strong waterdrivwwill have lower recovery as the gas trapped behindwater front could not be recovered.

The uncertainties in drive mechanism can be studied viathe use of sophistbted reservoir simulation models. Forexample, pm-development reservoir simulation studieswere carried out for Jemehf and F-62 fiekts to investigatethe impact of drive mechanism on gas recovefy.

As gas production continues, more historical data wereobtained. These data were analysad and matched to thereservoir model. By then, the prominent drivemechanism could be ascetiain. In the present producing

gas fields in Malaysia where sufficient productionhistoryare available, the presence of weak aquifer support wasobserved.

Well Requirement

The number of wells planned for sandstone reservoirsoffshore Peninsular Malaysia is to provide suffwientdrainage points to deplete the resewoirs, to developadequate well capacity to meet base demand andpeaking requirements and flexibility to cover geologicaluncertainties. in determining the o@numI Mifibei ofwells for initial field development, the sand mntinuity isgenerally assumed to be good and the drive mechanismwould be pressure depletion or weak to moderate waterdrive. If reservoir continuity is poorer or the aquifersuoom is stronger than expected, more wells may be__rr -.. .—required in order to maintain the long term productionprofile. In addition, well optimization should alsoconsidered tradeoffs between number of wells, tubingsize, compressiontiming and projected well downtime.

Well spacing is planned to achieve good reservesdrainage and minimize risk of reserve loss associatedwith potential reservoir variations. Most of the weiis arecentered at the crest of the reservoirs. For edge gaswells, they are located away from the gas-water contactsto delay potentialwater arrival in these wells.

For carbonate reservoim in the Central Luconia,Sarawak, the number of wells required from each fieldwas based on meeting the expected demand, takinginto account well deliverabilites to sustain plateauproduction for a certain number of years. In order toallow for any possible disappointing or mechanicallyunsuccessfulwells and also to provide some back-up forwells that will inevitably need to be shut in from time totime for operational reasons, additional wells wereplanned. Most of the wells were located along a circle(rinn of w~i~) close to the crest of the field structure.,. ...= -. , -.-—–

A .,, --* , -6 +hfi n,, mhnr nf dc I mrhar the nmsmtn Wllllllary VI LIIG Ilu,,, w-1 “t w“,.” “..”-. .... ~. ------development is shown in Table 1 below.

FIELD RESERVOIR PRESENTTYPE NUMBEROF

WELLS

Duyong Sandstone 13

Jerneh Sandstone 20

E-11 Carbonate 11

F-23 Carbonata 10

F-6 Carbonate 10

Table 1: Numberof wellsfor developedfields

550

- SPE29318 Chen Kah Seong, Darwis Husain and Abdul Hamid Abdul Karim 3

Well Completion Strategy

The gas fields located offshore Peninsular Malaysiaconsist of a series of vwtically stacked sandstones. Thewell completion strategy is designed to optimizehydrocarbon recovery from the field based on availablegeological and geophysical interpretatiins, whilerecognizing and providing tlexibiliiy for developmentuncertainties. Several factors were considered indetermining this strategy, including areal extent andreserves, reservoir parameters, reservoircontrollmonitoring need, water influx mitigation anddeliverabilityrequirements.

It would be impractical economically, to have separatecompletions for each reservoir. For completionpurposes, the sands have to be segregated into variouscommingling groups based on resefvoir size, proximity,pressure communication, reservoir qualiiy and necessityfor reservoir control and monitoring. To provideoperational flexibility, such commingled wells wereequipped with selective completions to allow reservoircontrollwell monitoring and enable shut-off of zonesshould aquifer strength be greater than anticipated andresult in water encroachment.

The wells that are located at the crest or near crastalarea of the reservoir and are considerably far from thegas-water contact were fully petioratad. Wells that arenot located at the crestal area and potentiallyaffected by‘wiii~i ~iEiiWWi~ilt ‘wf$i= @Wjj pf%fOiSM h thf$

upper part of the gas column. Where the qualiiy of thereservoir is poorer, welts were perforated with highershot density to minimize drawdown at the perforatedinterval. As the gas volume are distributed over stacks ofrasetvoir, initial development cells for complethig thewells in major reservoirs onty. The minor rasefvoirs willbe completed at a later stage through recompletion ofexistingwells.

A. -+s.t-mmmA +ha =~~r!st+ariqifi nankvsimai fmatnlrn@ nfm Uvnzlldwm?u, UIG m-W,w, Ii? ,“ ~v”,q,-, *“U.”,”” “,

the Central Luconia gas fieids are carbonate reefoidbuildups.Wfihin the carbonate buildup,the presence ofcontinuous tiiht streak layers may divide the gasaccumul~lon into separate resewoir systems which willnot be in effective pressure communication during thepenbd of fietd production. When there is communicationbetween individual layers of a field, single compltilonstrategy will apply. However, if there were differentpressure zones which limited communication, thecompletion strategy wiii be different. Tine uniformity inthe depletion at the same time provide adequateproduction capacity were taken into account. For anexample, in F62, it was noted that the bottom zone haslow porosity compared to the top zone. The presence ofa tight !ayer fwlher divided the zones into dlffemntpressure regimes. As a result, two rows of completionwere applied. One row consists of four wells were

targeted on the top zone while the second row of sixwells were targeted on the bottom zone.

Generally, wells were pwforated at 100 tt. intetvals withthe bottom perforations located about 1/3 above thegas-water contact in otder to avoid premature water---,coning.

Well Deliverability

The stabilized flow deliverability of a gas well is essentialfor planning the operation of any gas field. The flowcapacity must be determined for different backpressures at any time in the life of the reservoir and thechange of flow capacity with average rasefvoir pressurechange must be considered.

The most common method used for determining gas welldelivarabiiiiy is the multiipoint testing, in which a well isproduced at several differant rates. Measured flow ratesand well pressures were used to formulate inflowperformance equation. There are basically two types oftests which can be conducted, namely flow after flow—.. .and isochronal tests. 130tntype of tests were fraquentiyused for gas discovedes in Malaysia, depending on thetest objectives.

Once a well has been tested and the delivarabliiy orinflow performance equation established, it is sometimesdesirable to be able to predict how changes in caftainparameters w!!! #fan, ,,1& ~he infi~~ nnrfnnnanem Thaco

r-~u-mmmu-u--. I II--Vchanges may be the result of resewoir depletion or time,or may resutt from well workovers. The key valuesrequired for an accurate rate praditilon are gaspermeability, net gas thickness, rate independent skinfactor and turbulence factor. Other factors tike resenmirtemperature, gas viscosity, comprassibiliiy factor,drainage radius and wellbore radius are considered toremain constant. As a result, the well detiverabiliiy couldbe o~lmized.

For the sandstone resewoim offshore PeninsularMalaysia, some of the welts were completed as singleproducer while some were completed as dual producer.Single well completion used 5.5” tubing size while dualcomplatiin used 3.5” tubing size. For the carbonateresefvoits, all wells were completed as single zoneproducers with 7“ tubing size.

The range of well deliverability for the producing fieldsQ= shown in Tab!e ~.

551

Gas Fields Development In Malaysia SPE293184

E

FIELD

Duyong

Jerneh

E-11

F-23

F-6

RESERVOIR‘ TW3tNG iNiiiAL WZLL

TYPE SIZE (IN) DEUVERABILITITES(MMSCF/D)

Sandstone 5“ 10-40

Sandstone 3.5” 10-205.5” 50

Table2: Initialwelldeliierebilitesfor davelopedfields

Recovery Factor

The recowxy factors for the gas fields were derivedaccording to the appropriate resetvoir drive mechanismusing simulation model or matetiel balance study basedon certain abandonment conditions. The abandonmentcondh~ofi~dfie~ be~ie~fi fie~~ afid .-a I-..4 mm+haaiu uaaw wmttl9-compression suction pressure design. For the carbonategas reservoim, reservoir compaction also contributedtoadditional gas recovery. The recovery due to reservoircompaction in the cedxmate fields is estimated to beabout 2%. The range of recovery factors for thedeveloped fields are shown in Table 3.

lLzrEEsFIELD RESERVOIR ABANDONMENT AVERAGE

Jemeh I Sandstone I 250 I 80% I

I F-6 I Carbonate I 800 I 68% I

Tabie 3: Producing fieias recovery factor

Resewoir Suwelllance

The efficiency of a gas well or field operation requiresconstant monitoring of the total field and individual wellperformance in order to detect problems which mayseriously reduce gas recovery or producing capacity.Main parameters to be monitored include pressure, flowrate, cumulative productionand water produdton.

Periodic measurement of bottom hole pressure isconsidered essential to properiy analyze the reservoirperformance. Pressure Build Up (PBU) survey is carriedout to obtain reservoir pressure and other necessa~resenmir paremetem such as penneabifii, skin factorand resewoir boundary for each reservoir. Initial PBUsurvey is usually carried out for every newly completed

~~[!. Thn c,,hcammot SIIWCWS are CS@ed Out aS and, ,,” ““”””y ----- . --- -,when necassa~ based on the delivarabliiy test to checkany drastic dectine in resenmir/well productivity. StaticBottom Hole Pressure sutvay (SBHP) is carried out toassess the reservoir pressure depletion and arealpressure distribution. As the reservoir matures, thepressure measurements are carried only in selectedwells. The selected wells, can be refereed to as ‘keywelts’, usually represent certain percentage of the totalwells.

In raservoim where the production from severalsandstone resenmirs is combined or commingled in thewellbore, it is helptid to periodically run flowmetersurveys to establish flow profiles over the totalcompletion internal. This determines the distribtilon offlow out of or into dfierent zones. The sumy results arecrucial for resenmir performance monitoring andpredictionby simulation model.

!nn]a! pressure test SUIVSy with shut-in and buitduptesting of each producer should be conducted to defineinflowdeliirebiliiy parameters followingcompletion. It isimportantto measure the initialdeliverabilitiis as this willhave an impact on the subsequent well offtake capacity.The d~ribution of well deliverebitiies will also influencethe field offtake capacity. Subsequent well deliirebilitytest coukt be conducted at surfaceas this will not dsruptproduction and supply of gas to customers. Welldeliverebtiiy and rate performance analysis woutd enablerapid identiti~ton of any well productivitydeterioration.

Another important rasetvoir surveillance activity involvesmonitoring of fluid contact movement. In F-23 field forexample, an observation well was drilled vertically fromihe oenter of the platform down to the some 150 tt. ofSC@kW SeCtkXL Gas wet~i COfi’kiCt @AC] V4SS

periodically monitored by neutron log. The rise in theGWC was determined by comparing the cument GWClog with the base log. A plot of GWC rise with respect tofime ~n~lcr eumu~?ive fine nn-ult @inn was aenerstede

~..” p..-.. . .. . . .._- _______

Due to thin and consotiiated nature of the sandstones,reservoir compaction was not envisaged. However, thethick and porous formation encountered in thecarbonates justii close monitoring of the resenmircompaction. Radioactive tags were located at every 35ft. intend of the porous zone of the obsenmtion well tomonitor the rate of reservoir compatilon. FormationSubsidence Monitoring Tool (FSMT) logging nms madeat regular intetvals gave direct measurement ofcompaction at the specitlc pressure depletion at a time.A plot of compaction with respect to pressure declineWSS produced.

For resenmir performance monitoring, the mostcommonly used reservoir surveillance plot is thepressure-cumulative productionplot. By ptottingthe totalfield or resemoir gas remvered vetsus P/Z on various

552

SPE 29318 Chen Kah Seong, Danvis Husain and Abdul Hamid Abdul Karim 5

scales, productionproblems such as abnormal pressure,water influx, leakage or loss of gas, or bad data can bedetected. Once sufficient h~oty has been obtainedunder reasonably stabilized operating conditions, it ispossible to extrapolate the hWon’cal plot to theanticipated abandonment preeeum and tiius anWe at =fi

---

estimate of ultimate resenms. Unfortunately, severalfactors will affect the valiiiy of this method ofestimation. If a full or partial water dtlve is present, therate of pressure decline will be less than what wouldhave been obsemed had the resenmir been on a stmightpressure depitilon. Such a decline would be erroneouslyinterpreted as an indication of a much iarger reseiVOiT

----

than actualty exists. The obsetved performance mustthus be closely tied to the known geological contigumtionof the resenmir so that the reasons for the patlicularperformance observed can be propedy defined. Furtherevaluation to detect the presence and degree of thewater influx can be carried out using t-laviena-0deh3diagno~ic plot.

In addition, vatious typas of productii problems can bedetected by monitoringthe petformanca of a gas well byptotting production mtes of gas, condensate and waterversus time.

MAJOR SURFACE ENGINEERINGCONSIDERAllONS

Offshore Facilities

The gas development in Malaysia is carried out aftersome form of commitment to supply gas for a certainperiod of time is made with gas customers e.g. LNGplants or gas processing plants. A strategic ptan for theexectilon of the project will be developed to ensure thatthe committed demand are met. The development planis usually integrated with downstream facilities.

A processing and tmnsmission system will be installedtomeet the detivwy quantiiy and specifkation. Thefacilities will be designed to meet certain availability andreliabilityto ensure security of suppty.

As seveml operatom are invotved in the development,sevaml development concepts and opemtingphilosophies were adopted. The experience gained inthe past project provide useful tesson for the futureprojects.

Based on the development to date, it can ‘besumrnmized that offshore facitiiies shoukt fulfill thefollowingfunctions:

● To provide a platform from whti wells can be drilledand wellheads can be supported.

To pmvlde for the dehydmtion of the gas and Iiiuidstreams to etiminate the need for special tmnsportpipeline matefiats which woutd otherwise benecessary due to the presence of COZ in the gasstream.To provide accumte metering facilities for themeasurement of gas, condensate and water volumesfor reconciliationpupses.

To mwide accommodation and Iiie SUPPOII foropen&ions and maintenance personnet -

Platform Configuration And Sequence

The initial development for E-1 1 (FQure 2) and Duyong(Figwe 3) fields was based on conventional smallmultiiplatforms (four-platform production complexarrangement consist of drilling, production, kingquartem and vent ptatforrns), fixed stmcture complexes,dedicated gas inlet, slugcatcher and condensatestabilisatiin faciliii (appliible only for development inCentml Luconia). At E-11, being the focal complex forCentml Luconia, there is an additional pipeline riserptatform. Provision is made at both fields for installationof a sepamte compression ptatform at a later stage in itsproducing Iiie.

A- .L- -1..---.1 ●..- ..-- Z ~m~~ 4hn i. fm+%mkra.* 11!8 u=[[~llu Iul ~44= lkCX4=&t, LIIU 11111-- .“-”,””

were expanded to include other sources of gas. InPeninsular Malaysia, associated gas gathering schemewas implemented. The system was connected to the~Jy~ng ~=~ r4M .Iqnnh nac fdd was bf’Q@?? O!?S!RXWl

w-. “- ,,”.. u - ----- ---- --in 1991 to meet the increasing gas demand. Unlike thecartier developments (E-1 1, Duyong, F-23 and F-6),EPMI employed the three-platform production complexarrangement for the development of Jemeh field. Theproduction and living quartets were integmted into asingle platform (Figure 4). Another gas inletklugcatcherwas Malted as the Duyong slugcatcher does not havesufficient capacity. In Samwak, development of F-23 andF-6 fields (Fiiure 2) also utiliied the four-ptatfonnproduction complex arrangement, simitar to the E-11field. The concept was adopted at that time as it was fettthat such arrangement coukt provide maximum flexibilityand safety of operation at an acceptable level ofincremental cost over integmted platforms. After F-23and F-6 fietds were put on produtilon, a second trunklinewas installed in 1990 to improve the raliibitiiy andsewrity of gas suppty.

In Samwak, a major development involving 11 gas fieldswas under&akento supply gas to the three additionalLNG tmins in 1995. The development will consist of twostandalone complexes and a riser platform which will beinstalted near the existing E-11 comptexes. A dedicated-.. :..14 .1.....nn4Aa. ~p~~ua IIIISL, alu~!#aLwIvl @*~fi~*e Stetipsetion

facilities will be constructed. The new developments

553

6 Gas PieIds Development In Malaysia SPE 29318

could not utilise existing E-1 1 riser for tie-in andsubsequent utilisation of existing trunkline owing tolimited slots and the nature of the gas which is sour.Unlike the E-1 1, F-23 and F-6 developments wherefour-platform production arrangement concept wereadopted, development of the gas fields will seeintegration of some of the facilities to minimise the costof development. Similarly, Lawit gas development isbeing implemented in Peninsular Malaysia to cater theincrease in gas demand. New integrated pletfonm andanother trunkline to shore will be installed in 1998 forstatt-up in 1997.

In formulating the overall concept on the recentdevelopment, future requirements were also taken intoconsideration where future tie-ins and operationalflexibiiiiy protilons have been incotporeted in thedesign. Thus, for Mure developments, the clusterconcept approach will be adopted to formulate theultimate system configuration where the utWation ofavailable infra-structure is maximized. For example, inthe development of Lawit field, provMons were made tocater for future tie-in from nearby fields.

Process And Compression Requirements

Each development was o~tmised to meet processrequirements and gas supply obliitilons. The gas fromthe wellhead will require condensate separation,dehydration and compression prior to transmission tofutther processing plants onshore. The condensate willbe either reinfected into the gas pipeline (E-11, F-23, F-6and Duyong fields) or pumped into dedicated trunkline(Jemeh field) for transmission to shore. The presenttiweiqxnerit facilities are dasigmxt ptilmati!y tcsafeguard against corrosion and erosion. The mainhazard for the trunktine is sweet corrosion caused by thecarbon dioxide present in the gas. The design capacNesfor the producingfields are as follows.

In Peninsular Malaysia gas development, compressionfacilities are required at earty stage of production. Thecompression faciliies were designed for certainavailability where sufficient redundancy in equipmentwere incorporated. In formulating the overallcompression requirements, the following are considered

Horse power requirements.

Sparing philosophy.

Future flexbiliiy.

Sharing of facilities.

Standardization.

CONCLUSIONS

1. In sandstone reservoim off%horePeninsular Malaysia,well spacing is planned to achieve good reservesdrainage and minimize risk of reserve loss associatedwith potential resetvoir variations. This resulted inmore wells drilled in sandstone resewoirs. On theother hand, well spacing is not ctiicel in carbonate

--,-;= --A M =* nf ihn wdlc warm Iomtd alma arfbzl Wull= allu 881O*.“, .,,” ..”.- ..”,.. . ----- -.-..= -circle (ring of wells) close to the crest of the fieldstructure.

2. The gas fields located offshore Peninsular Malaysiaconsist of a series of vertically stacked sandstones. Itwould be impractical to have separate completionsforeach reservoir. For completion purposes, the sandshave to be segregated into various comminglinggroups. On the other hand, the carbonate reservoirsare of reefoid buildups.The wells are completed overthe gas bearing zones, with the bottom perforationslocated about one third above the gas-water contact.

3. For the sandstone reservoirs, some of the wells werecompleted es single producer while some werecompleted as dual producer. Single well completionused 5.5” tubing size while dual compl~lon used 3.5”tubing size. For the carbonate resewoim, all wellswere completed as single zone producers with 7“tubing size.

4. In carbonate reservoirs, it was observed that resetvoircompaction also contributeto recovery factor.

5. EPMI operated platform is based on integratedconcept whereas PCSB/SSB operated platforms arebased on platform complexes concept. However, in

--- ac-m- 4%-1Ac-- ~~~; “mlthrnn I NCthe deveioplmu~itWI~u= IJ=IUSJUIawwl~~oiDalt!,,-- ~,.-plants, SSB integrated some of faciliies to minimizethe structure for cost saving in deeper waterdevelopment.

6. EPMI operates with dedicated gas and condensatepipeline while PCSB/SSB operate multiphase pipelinefor transport of gas and condensate to shore.

ACKNOWLEDGMENTS

The authors wish to thank the management of PetroliamNasional Berhad (PETRONAS) for the permission topubliih ths paper.

REFERENCES

1.R. Thambydurai,M.R. D~on, :Planning”, paper

A.F. Mustapha, K.H. Mueller and“Jemeh Gas Field DevelopmentOSEA 88199 presented at the 7th

Offsho& SOuth East Asia Confe&me, Singapore, 2-5February 1988.

554

SPE29318 Chen Kah Seong, Danwis Husain and Abdul Hamid AbduIKarim

2. P.Y. Wee and S.L. Liew, :” Development Planning OfThe F6 Gas Field In Central Luconia, OffshoreSarewak, Malaysia”, paper OSEA 88198 presented at7th Offshore South East Asia Conference, Singapore,2-5 Febmaty 1988.

3. Gaffney, Cllne and Associated, : “An IndependentAudit Of Non-Associated Gas Reserves, OffshoreSarawak”, report published for PETRONAS,PETRONAS Carigali and Sarawak Shell, January1993.

4. Oil & Gas Consultants International, Inc. and Dr. H.Dale Beggs, : “Gas Produ&lon Operations”, 1981.

5. F-6 Development Plan, Unpubliihad SSB report 1966.

7

6. Duyong Revisit 1 Field Development Plan,Unpublished PCSB report 1994.

555

MAI AVCIA ● ~Rnnl ICING GAS FIELDS LOCATION

/. t

sOUTH

THAIIAND CHINA /--,

SEA>/. .—_”

\

t

L\

\

‘\\ :

SUMTERALEGEND

KALIMANTANo PRoDUCINGGAS FIELD

\ 1------ .-- .-.-.,

FIGURE 1: FIELDS LUGA I IUN

El 1

\ \\\

“//’

/.

FIGURE 2: CENTRAL LUCONIA FIELDS IAYOUT “

556

FIGURE 3: DUYONG FIELD LAYOUT E

*

MC

Ulllm

. ... ———....— _

Im.

i o I.-l1 GEN. Ismml

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.

I.

1 i

FIGURE 4: JERNEH COMPLEX LAYOUT ‘

557