North Sumatra Basin: Its Evolution and Sedimentation Evolution

NORTH SUMATRA BASIN: ITS EVOLUTION AND SEDIMENTATION EVOLUTION

ALIT ASCARIA Ph.D.

CCOP. P1W2: North Sumatra-Merggyui Basin Case Study. Medan & Parapat, 27 – 30 April 2010 Agenda

• Introduction • Regional Geology of North Sumatra • PlPaleogeograph y • Petroleum Systems • Conclusion INTRODUCTION

BASEMENT LITHOLOGY

Comparison of the Carboniferous, Permian, and Triassic sequences in the Sibumasu terranes of eastern Sumatra, West Malaysia and Thailand, and Gondwana Terrane in NW Australia

(Barber et al., 2005)

CfCfComparison of the Carboniferous, Permian, and Triassic sequences of the eastern Sumatra Sibumasu Terrane and GRDC map sheets, the Indochina Terranes of west SdhMlPilSumatra and the eastern Malay Peninsula Cross section of the Sumatra Subduction System from the floor of the Indian Ocean to the Malay Peninsula

(Barber et al., 2005) BASEMENT TYPE

(Hutchison,1994) (In Barber et al., 2005) BASEMENT CONFIGURATION

(Barber et al., 2005) During the Mid – Late Triassic, the whole of Sumatra and Peninsular Malaya were subjected to NE- SW extension with the ftifformation of several lth north -south and NW – SE graben structures, the Kualu and Tuhur basins in Sumatra and the Semantan and Semanggol Basin in Malaya, separated by intervening horst blocks.

(Barber et al., 2005) Sample From POLONIA‐1

2741.64 – 2741.7m Argillaceous Sandstone (Kualu Fm.); the chief detrital grains of this sample are quartz; the grains have tangential and straight grain contacts withintergranular spaces infilled with authigenic clays and calcite cement.

PPT‐2A PPT‐1

Polonia‐1 BHR‐1 PPT‐2A

Sample PPT‐1 Well, 2595m; fine SS; quartz grains, and chert rock fragments with slightly sutured grain contacts; visible porosity generaly 5 %, llllocally idincreased to 10 – 1%15%.

Mulhadiono, 1984

Kualu Fm.Eq. (2,525 ‐2,725m); Max.porosity is 12%, average 2‐5%, Sw is about 85%, and K is <10mD, with very fresh water <1000ppm Cl. Sample PPT‐2 Well, 2650.8 – 2650.86 m; lithic SS; quartz grains dominant, poorly sorted, and individual grains are– 15%. PPT‐2A PPT‐1

Polonia‐1 BHR‐1

Mulhadiono, 1984

(Andreason et al., 1997) (Andreason et al., 1997) Schematic cross section showing geological model of N. Sumatra basin

(Widarmayana, 2007) (Barber et al., 2005 modified)

(Hakim et al., 2007)

North Sumatra Tectonic Elements (Present day)

(hd(Sosromihardjo, 1999)

Tertiary structural and basin evolution of Sumatra

(Barber et al., 2005) Present day internal framework of the North Sumatra Basin

(modified after Kamili et al., 1976)

STRUCTURAL FRAMEWORK OF N.SUMATRA BASIN (Clure, 2005) Basin development : Syn rift period Basin development : Late rift & Sag periods (Collins et al., 1996) Schematic cross section showing geological model of N. Sumatra basin

(Collins et al., 1996) Play Concept and Risk

BOUGUER GRAVITY IMAGES AND CONTOUR LINES MAP

50km 4.2

4.0

3.8

mGal 3.6 35

25 3.4 20

10 3.2 5

-5

3.0 -10

-15

98. 2 98. 4 98. 6 98. 8 99. 0 99. 2 99. 4 99. 6 99. 8 100. 0 (Geo Prima Energi, 2009) BASEMENT CONFIGURATION (BASED ON gravity in mGal, contour intervals 1 mGal SEISMIC MAPPING & GUIDED BY GRAVITY DATA) BURIAL HISTORY BASED ON POLONIA‐1 WELL

Top Oil Window at 2400 m

Expulsion on Pliocene (4 Ma) MATURATION MODELLING ON

RANTAU DEEP STRUCTURAL HIGH AND LOW North Sumatra Basin O M P PHFmMISS SEUREULA 0 SEUREULA GEBANG LOW North Sumatra Basin KEUTAPANG 1000 M P P Fm 0 O H MISS SEUREULA SEUREULA

2000 KEUTAPANG BAONG 1000 Depth (m) Depth 3000 98°30' 98°00' 99°00'

BELUMAI 2000 BAONG Early Mature (oil) U D 4000 0.7 to 0.8 (%Ro) PRE-BELUMAI Mid Mature (oil) 0.8 to 1 (%Ro) N

Late Mature (oil) (m) epth 1to13(%Ro)1 to 1.3 (%Ro) RANTAU DEEP DD Main Gas Generation 5000 4°30' 3000 5200 1.3 to 2.6 (%Ro) BELUMAI 30 20 10 0 Age (my) BAMPO Early Mature (oil) BSMT 0.7 to 0.8 (%Ro) 4000 KSB Mid Mature (oil) 0.8 to 1 (%Ro) U D Late Mature (oil) 1 to 1.3 (%Ro) U D Main Gas Generation 1.3 to 2.6 (%Ro) U D 5000 CMP=FM;TH=THF;MAT=LL KST DARAT UTARA-1A 30 20 10 0 BURIAL HISTORY & MATURITY DIAGRAM DARAT UTARA-1a WELLTG=1;TI=0.5;EXP=TR;PRM=MKC Age (my) North Sumatra Basin DI=1.000 U D interpreter: nhr M P P Fm D U 0 H KEUTAPANG PTD PTT GEBANG LOW 1000 4°00' GEB BAONG SEC D U D U BURIAL HISTORY & MATURITY DIAGRAM BATUMANDI SELATAN - 1 WELL CMP=FM;TH=THF;MAT=LL 2000 Batumandi Selatan-1 TG=1;TI=0.5;EXP=TR;PRM=MKC

D U DI=10

Depth(m) North Sumatra Basin 00 DRU- interpreter: nhr BELUMAI PPT O M P PH Fm U D 3000 1A BAMPO 0 MISS SEUREULA Early Mature (oil) SEUREULA 0.5 to 0.7 (%Ro) MEDAN Mid Mature (oil) 0.7 to 1 (%Ro) 4000 Late Mature (oil) 1 to 1.3 (%Ro) Main Gas Generation 4500 t = 0 22 20 15 10 5 0 1.3 to 2.6 (%Ro) 3°30' Age (My) KEUTAPANG nana/c/mydocu/bmod-1d/nsb/dru1mat.ppt D U U D 1000 TEBING TEBING LEGEND : T (m) INGGI DEEP INGGI hh CMP=FM;TH=THF;MAT BASILAM-A1a =LL BURIAL HISTORY & MATURITY DIAGRAM BASILAM-A1a WELL TG=1;TI=0.5;EXP=TR;PRM=MKC North Sumatra Basin DI=1000 HIGH Dept BMS-1 interpreter: nhr M P P Fm 0 H MISS SEUREULA BAONG SEUREULA 3°00' LOCAL HIGH 2000

LOW Early Mature (oil) KEUTAPANG 0.5 to 0.7 (%Ro) TRANSITION 1000 Mid Mature (oil) BELUMAI LOCAL LOW 0.7 to 1 (%Ro) BSMT BAS- Late Mature (oil)

(m) BASIN SLOPE 1 to 1.3 (%Ro) hh BAONG 3000 Main Gas Generation 1A t = 0 1.3 to 2.6 (%Ro) Dept 2000 GAS SAMPLES 40 30 20 10 0 KSB GONDWANA,1980Age (My) BELUMAI BAMPO BSMT Early Mature (oil) 0.5 to 0.7 (%Ro) 3000 Mid Mature (oil) 0.7 to 1 (%Ro) Late Mature (oil) 1 to 1.3 (%Ro) Main Gas Generation 3600 t = 0 20 15 10 5 0 1.3 to 2.6 (%Ro) Age (My) SRG - 5

104 Malaysia PEUTU NORTH Sumatr Platform 0 Edge in d MAL o a n e s ia AC 3 S e a CA ST RAIT Index Map Outer Platform NORTH

BELUMAI 0 10 km

GOS-1

RTU-1 Middle Platform GOS-2A RT-52

KS-2

ARO-2

SR-2 ARO-1 KLD-1 ABS-1

PUSHUNG

SEK-1 SEC-4 BES-1 NSO GEB-9 P.BERANDAN SCG-1 BES-2 TST-1 Inner ASAHAN-01Platform

DRU-1

BAS-AL

PPT-2A

WP-2 Su BTM-1BTM-1BTM-1BTM-1 MEDAN m

at BMS-1 ra DIS-2 LEGEND Shear Fault System POL-1

BHR-1 Environmental Set-Up TWA-1 Transistional TEBING TINGGI Littoral Nearshore Transistional/Inner Platform

Middle Neretic Shelf Clastics / Isolated Carbonates Shelf Clastics /Isolated Carbonates Outer-Middle Neretic h Platform Edge Outer Neritic Open Shelf

Sediment Transport Direction an Hig Ash DEPOSITIONAL FACIES MAP : BELUMAI-PEUTU FM. Sedimentology, Petrography Middle Miocene - NSB

SW N 11 - DUYUNG SAND NE SL Quartz arenite DUYUNG TST HST Q SAND LST Subarkose Su blitharenite

BRUKSAH/PARAPAT BAMPO NORTHERN SOURCE N 12 - GEBANG SAND SL Arkosic Lithic GEBANG SAND HST/SMST TST Arenite Arenite HST 0 25 50 75 100 F L

BRUKSAH/PARAPAT Q

Subarkose Sublitharenite ..... SOUTHERN MIDDLE BAONG SAND .. SOURCE SL

HST LST GEBANG SAND Arkosic Lithic MFS/DLSF HST/SMST Arenite Arenite

LST 0 25 50 75 100 F L

SR-AS NOT TO SCALE BARISAN UPLIFT LANGSA 101 °

TANJUNG P Medan RTU-1 N

LOKOP 1 Muku -0° RT-52 2 Rantau Str. 98 F -3° KSB-1 U K KSTSerang JayaA RA FAULT UTACANE FAULT

K.Simpang Timur ULT Perapen SR-02 INDEX MAP Kuala Dalam J-O-EIA BTR KLD-1 RANTAUSLP-1 SRG-A1 SBU-A A R O R-O-5 Sungai-A3 R-O-6 PTB ABY P. Sembilan PLW-1PSL-1 R-O-7 Pulau Panjang Susu-A1 Pusung-1 Sem-A1 J-R-E2 A-1 Paluh Tabuhan Timur Sungai SUS-A1 Gebang SEK-A1 TKM-1 SCG-1 Securai PBR-1 SAL-90 Telaga Said A1 TST-1 Telaga Darat DRU-1 B1 A R U TAP-1 LANGKAT - MEDAN Basilam - A1

Pantai Pakam Timur

PPA-1

TPS-1 PPA-2 Batu Mandi 3 1 Wampu 2 M E D A N BMS-1 Diski

Polonia

DISTRIBUTION MAP OF PROVEN STRUCTURE (Mod. DOH Nad 2005) TWT Structure Middle Baong TWT Structure Belumai Gebang-deep & Tanjung Pura Area Gebang-deep & Tanjung Pura Area

TWT Structure Basal Sand Gebang-deep & Tanjung Pura Area Reservoir Thickness and Quality N-S wells correlation S N

Belumai PreTertiary 100 Fm Carbonate m Divs. NSO- 1S NSO- 3S Kerinci-1

PreTertiary

Kambuna-1 Carbonate

Kemiri-1 Pusung-1 Kerinci-1 Pusung-1 Kemiri-1 Kambuna-1 Tonjol- 1 NSO-1S NSO-3S Tonjol-1 Belumai Fm Water Bottom

Julu Rajeu

Seurula ASH05-43A Keutapang

Middle Keutapang

Baong

Belumai

PreTertiary

Series of Half Graben System Water Bottom W Julu Rajeu E Seurula Keutapang

Middle Keutappgang

Baong

Belumai

PreTertiary

Glagah oil Accumulation -fractured PreTertiary Limestone

Untested Play in West Glagah

East Perlak -1 Spud date: oct.1981 Objective: Turbidite sandstone Baong Formation, carbonate Peutu Formation and sandstone of Brukash Formation. Deep well drilled in Perlak Platform

RltfEtPlkResult of East Perlak-1 Baong Formation consists mainly of interbedded fine sandstone and shale Peutu Carbonate consists of interbedded fine san ds tone an d p lankt oni c f oram bioclastic wackestone in the upper part and planktonic foram bioclastic wackestone in the lower part. Depositional environment is open mariditiine condition. Brukash Formation composed of interbedded fine sandstone and shale. TD at Pre-Tertiary Dolomite? Bouguer Gravity Map

Gravity map showing main structural trends. Blue denotes thick and red denotes thin.

Correlations – Northern Basin Correlations – Southern Slope Area Well data with results

S N

NSB-D1

GR DT

Baong

Bampo

Parapat Oil Generation

Early Oil Generation

In BLD-1 Well at the time < 4 million year ago estimated had happened early stages of the oil generation in the upper part of Prapat Formation Thermal Geohistory

Oil Generation

Estimated the formation of hydrocarbons in the BLD-1 Well happened on the upper part of Prapat Formation at temperature 105° -120° C and occurred in 2 million years ago Conclusion

• There are potential for pre-Tertiray play in North Sumatra Basin (NSB) • Oligo-Miocene carbonate still the main target for exploration in NSB. • Finding prolific basin like Java and Lho Sukon Deeps is a must in NSB for high impact exploration target (Arun/NSO size). • Distribution of Middle Baonggp sandstone still poorly understood especially in Andaman area. • For sandstone play need to have a good trap since tectonic is relativelyyg intense during Plio-Pleistocene. • Despite all the risk, NSB still have a potential for exploration to finding big hydrocarbon resources. • Gas shortage to LNG/PIM/DMO need to fulfilled by explore the NSB