#1ENERGI & & SUMBER A MINER MINERA DAYA LEMIGAS ОСОР THE NORTH SUMATERA BASIN : GEOLOGICAL FRAMEWORK & PETROLEUM SYSTEM REVIEW By the Delegation of Indonesia : Bambang Wicaksono TM* Jonathan Setyoko H* Hermes Panggabean** * Lemigas ** PSG KRABI, 12-15 MAY 9#2LEMIGAS OUTLINES • INTRODUCTION GEOLOGY OF NORTH SUMATERA BASIN • PETROLEUM SYSTEM • HYDROCARBON POTENTIAL • SUMMARY#3LEMIGAS 8°00' 6°00'N 400'N INTRODUCTION 100 km/ MYANMAR THAILAND MERGUI BASIN Krabi MALAYSIA THAILAND INDONESIA NORTH SUMATERA BASIN SUMATERA The Mergui - North Sumatera Basin occupies an area of cross-border among 4 Countries: Thailand, Malaysia, Indonesia, Myanmar. North Sumatera Basin is located in the Southern part of the larger Mergui – North Sumatera basin - 96°00'E 98°00'E Andreason, et. al., 1997#4LEMIGAS TECTONIC SETTING INTRODUCTION VICINI THAILAND W7/38 M-1 MYANMAR THAILAND MERGUI RIDGE WEST MERGUI B-BASIN SUB-BASI CENTRAL EAST MERGUI SUB-BASIN W9/38 W8/38 SHELF W1/38 W2 MERGUT W3/38 THAILAND KHLONG MARUI FAULT W4/38 W5/38 NORTH SUMATRA BASIN MALACCA PLATFORM W6/38 THAILAND MALAYSIA PM1 ARUN HIGH PEUSANGAN MOUNTAIN BARISAN SUMATRA SUMATRAN FAULT SYSTEM 96°00' UST FRONT ARCH ASAHAN 6200 480 Andreason, et. Al., 1997 The Mergui - North Sumatera basin is bounded by convergence of Mergui Ridge with continental crust of Sunda Craton to the north, Asahan Arch to the east, Barisan Mountain to the south, and the Mergui ridge to the west. The main tectonic elements dominated by relatively N-S and NW-SE trending highs and deeps These highs and deeps divide the larger basin into several sub-basins 100#5GEOLOGY of the NORTH SUMATERA BASIN#6LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN NORTH SUMATERA BASIN North Sumatra Basin Fore-Arc Basin Fore-Arc Ridge Accretionary Wedge 2° N Malaysia Sunda Craton Asahan Argh Barisan Mounta AM SH A4 Tigapuluh High South Sumatra Basin 2° N- ➤ North Sumatera basin is a back-arc basin that occupies an area of 60,0000 sq. km in the offshore and onshore area of the Northwestern part of Sumatera island This basin is known as prolific hydrocarbon bearing basin in western Indonesia and produces oil and gas. Sunda Basin Central Sumatra Basin ntains Mentawai Fault Active subduction Zone Sumatra Fault Top of Melange Wedge Toe of Melange Wedge Relative Plate Motion N6°E Sunda Trench A Active Quaternary Volcanoes 0 100 200 300 400 500 km Approximate Scale 98° E Lampung High ΔΔ 4 Pertamina - C&T P.S.C Coastal Plains Block 105° E W. Java Basin 8° S Hydrocarbon Exploration history began in the late 19th century. The first oilfield in the North Sumatera Basin is Telaga Said oilfield (1885). The discovery was followed by Darat oilfiled (1889), Perlak (1900), Serang Jaya (1926), Rantau (1929), Gebang (1936 and Palu Tabuhan (1937). The most significant field in the basin today is Arun gasfield which was discovered in 1971. Total initial reserves of this field was estimated to be 17 TCF. Java Trench#7LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN TECTONIC ELEMENTS 95°E ANDAMAN SEA OCEANIC CRUST N.S MERGUI RIDGE Sot-basin Banda Aceh MERGUI BASIN 100% N Kilometers 125 MERGUI MICROPLATE Malacca Platform Pase Arun High Sub-basin LEGEND: STRUCTURAL HIGH STRUCTURAL/BASINAL LOW MERGUI MICROPLATE ANDAMAN SEA OCEANIC CRUST NORMAL FAULT TRUST FAULT 95°E Yang Besar High Fault System Tamiang Sub-basin _ Lokop-Kutacane Ra SUMATERA Aru Platform Medan MALAYSIA N.S 100 The main structural elements are dominated by N-S and NW-SE trending direction. Three tectonic events occurred in the basin Initial extension phase in the Late Eocene - Early Oligocene; Wrench tectonism in Mid Miocene; and Compressional tectonism during Plio-Pleistocene. The N-S trends represent Pre- Miocene Structure, and the NW-SE are Post Miocene structures 100°E PND, 2006#8LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN GEOLOGICAL CROSS-SECTION SW KETTIBUNG ANTICLINE TANGSARAN ANTICLINE BAONG ANTICLINE DJAMBOR- BARISAN MTNS BATANG SYNCLINE PENARON SYNCLINE BARISAN FOOTHILLS BAONG BEUTY BAMPO APPROX LINE OF SECTION BLOCK "A" ALUR SIWAH GAS FIELD (PEUTU REEF) PENARON VALLEY KEUTAPANG ESCARPMENT UP MIDDLE BAONG LOWER PEUTU? PALEOZOIC LIMESTONE BAONG SCALE MALACCA STRAITS BLOCK"A LANGSA BAY UPPER SEURULA KEUTAPANG JULU RAYEU MIDDLE LOWER BAONG AI & BRUKSAH CLASTICS PRE-TERTIARY BASEMENT JULURAYEU OIL FIELD (SEURULA) PERLAK OIL FIELD (KEUTAPANG) OIL SEEPS BAONG 100 NSB NE OIL & GAS FIELDS (PEUTU REEF) In the southwestern part of the basin, the sediments were highly folded and faulted due to Barisan uplift SEURULA KEUTAPANG SL UPPER MIDDLE LOWER TAMPUR TAMPUR & PRE-TERT PRE-TERT METAMORPHIC & IGNEOUS BASEMENT#9LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN General Stratigraphy Chrono-Stratigraphy Lithostratigraphy N Zone Super Cycles M. Yrs System Series NSO Extension Peusangan Western High 'B' & Pase Malacca Shelf Asamera Pertamina Quarter- Pleisto- 1.65 3.50 nary cene L N23 N22 N21 Julu Rayeu N20 Seurula N19 5.20 N18 N17 -10.20 -16.20 T T T T 20 20 25.20- 30 30 36 39.4 49 49 Tertiary Eocene Middle Paleogene Late Oligocene Early Late Miocene (??) Diorite Eocene Basalt Late Early Neogene Miocene Sligi Middle Late Plio- cene E Pre-Tertiary Seurula Keutapang N16 L. Baong Ss N15 N14 10.5 (96) N13 Seumpo Peunulin Baong N12 (13) N11 N10 N9 Malaka N8 N7 TB 2 Arun Peutu Arun Belumai N6 Parapat/Bruksah Meucampli Bampo Tampur N5 z NE @@ EEEEEEEE E 100 TB 3 Global relative Change Of Coastal Onlap (Vail et al., 1977) Landward 1.0 0.5 Basinward 0 (07) (17) (28) TI 21 (22) 30 30 TB 1 (226) (24) (267 (29) (32) Initial deposition of sediments began in Late Eocene -Early Oligocene time in very limited Area as initial syn-rift infill Main sedimentation in the basin took place during Late Oligocene to Pleistocene Maximum sedimentary rocks thickness is up to 6.000 m in the deepest part of the basin. TA 4 (36) (38) 39.4 TA 3 49.5 (44) (455)#100° Q' LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN Western Indonesia Paleogene Rift-Basins STRAIT OF MALACCA Luconia Microcontr KA Kucing Zone L Ketunggu Bcoin Melawi Basin Eccexe-očene Volcemic 10 Bawean Arch Meratus Mits LEGEND Norm at fanit Strike-slip Fault Sunda Basin Asri Basin Arjuna -Bac Kaimun Jowa Arch Rift Basin Suture 100 ➤ During paleogene Time, sediment deposition in the North Sumatera Basin occurred within some N-S trending Rift basin#11LEMIGAS GEOLOGY OF the NORTH SUMATERA BASIN Western Indonesia Neogene Sedimentary Basins 0 10 North Sumatra Basin MALAYSIA atuna ind Area West Natuna Bacinal Area Central Sumatra, Basin Meulaboh Casin Barisan Uplift Mentawa Basin INDIAN OCEAN LEGEND Normal fault Strike-slip Fault Basin Outline Bengkulu Basin Neogene codi Paleogene. Cad Zone of Uplift South Sumatra Basin Luconia Micro-continent Teton Bin Kalimantan Barto Bocin L Kulei Bcsin Pasir Basin NW Java Basin Asem-asem Besin NE Java Basin. Java Southern Mils Uplift MADURA BRA BALISPA SULAWESI 100 Sedimentation widely spread during Neogene Time. Thick sedimentary sequence and basin outline were formed during this period#12PETROLEUM SYSTEM REVIEW#13LEMIGAS PETROLEUM SYSTEM REGIONAL HEAT FLOW MAP (Modified from Kenyon & Beddoes, 1977) 100 Average Heat flow in the North Sumatera basin is relatively high (> 2 HFU). It is suitable for source rock maturation Explanation: > 3 HFU 2-3 HFU 1 - 2 HFU <1 HFU#14Number of Samples LEMIGAS PETROLEUM SYSTEM SOURCE ROCK POTENTIAL ■Shales & mudstone of Bampo Formation and Peutu Formation. Outer neritic shale of Lower part Miocene Baong Formation. 50 50 Peutu Fm. 40 Bampo Fm. 30 20 10 Hydrogen Index 1000 800 600 400 200 0 0 0.5 1.0 1.5 2.0 2.5 3.0 0 20 40 Total Organic Carbon (wt.%) ။ PEUTU FM. BAMPO FM. Shales & mudstones of Bampo & Peutu Formation were dominantly tipe III kerogen with TOC range from 0.5 % to 3%. ။ 60 80 100 120 140 160 Oxygen Index Buck & Mc. Culloh (1994) 100#15100 PETROLEUM SYSTEM RESERVOAR POTENTIAL LEMIGAS ■Early Miocene Belumai sandstone ■Miocene reefal carbonate (Arun limestone, Malacca carbonates) Miocene turbidites of Baong sandstone Upper Miocene to Pliocene Keutapang sandstone Pliocene Seurula sandstone NORTH SOUTH A12 A43 A23 A33 A35 A50 A31 A52 NORTH * * * * * * * * A12 * A43 A33 A28 A35 A50 * * * * * POROSITY BAMPO SHALE TOP ARUN LS BAONG SHALE V GOOD (>20%) GOOD 15-20%) FAIR (10-15%) POOR (<10%) ARUN FIELD POROSITY DISTRIBUTION WITHIN ARUN LIMESTONE CONTROLLED BY TILT HORIZONTAL SCALE MILES 0 KMS PERMEABILITY EXCELLENT >> 100 MD V GOOD 50 100 MD GOOD 10-50 MD FAIR 1-10 MD POOR <<10 MD FIGURE 16 TOP ARUN BAONG SH LS BAMPO SHALE ARUN FIELD PERMEABILITY DISTRIBUTION WITHIN ARUN LIMESTONE CONTROLLED BY TILT HORIZONTAL SCALE 0 MILES KILOMETERS SOUTH A31 A52 * * FIGURE 17 Abdullah & Jordan (1987)#16LEMIGAS PETROLEUM SYSTEM SEAL POTENTIAL ■Impermeable shales of Belumai, Baong, and Keutapang Formations NSO Extension Lithostratigraphy Peusangan Western High 'B' & Pase Malacca Shelf Asamera Pertamina cene (??) Diorite Seumpo Peunulin Sligi Parapat/Bruksah Meucampli Peutu Julu Rayeu Seurula Keutapang Baong Seurula L. Baong Ss Malaka Arun Belumai Arun Bampo Tampur 100#17LEMIGAS PETROLEUM SYSTEM TRAP POTENTIAL ■ Structural trap ■ Stratigraphic trap (Reefal Carbonate and clastic) ■Combination structural/stratigraphic trap NW 205 108 Z.560 Z160 Z270 Z.380 C Z.460 B 4803 2.640 RANTAU FIELD SE S 141 45 40 16 * ** 99 7 104 20 52 Subsea Depth (m 21 20 -100 -200 GOC Z.330 -300 2 400 B --400 Z.460 B Z.380 A TD.414 m TD.596 m TD.468 m2560 Z.400 B -500 TD.408 m Z.480 2.590 10/687 SS 2.590 OWC -600 TD.597 m TD.693 m TD 853.1 m -700 TD.755 m --800 TD.890 m -900 0 1000 m F-1000 TD.1060 m STRUCTURAL TRAP GEUDONDONG FIELD 25A 23 24 16 * * * LOWER KEUTAPANG FM GOC-809 m GOC-806.5 m TD.829.5 m 10/754 SS 0 Impermeable 6 2 OWC TD.868 m TD:884 m TD 8752m TD.880.3 m 1000 m TD 902 2m N Subsea Depth (m) OWC-860 m COMBINATION STRUCTURAL & STRATIGRAPHIC TRAP -800 -900#18LEMIGAS PETROLEUM SYSTEM HYDROCARBON GENERATION & MIGRATION ■First Hydrocarbon generation was suggested at Middle Miocene Time ■Critical moment occurred around Plio-Pliocene ■Migration pathway occurred through up-dip and vertical faults 200 150 100 70 60 50 40 30 20 10 Mesozoic Cenozoic o Geologic Time Scale R LEML J K Tertiary Petroleum E L Paleo Eocene Olig. Miocene PP System Events BB P Bg K UR P S Rock Unit Source Rock Seal Rock Reservoir Rock Overburden Rock Trap Formation Generat-Migrat-Accum Preserv.-Degrad-Destr. Critical Moment Buck & Mc. Culloh (1994)#19LEMIGAS PETROLEUM SYSTEM HYDROCARBON PLAYS A 0 Depth (Km) Arun Field * Seurula & Julu Rayeu Fms. R 2 Keutapang Fm. R 3 Baong Sandstones Arur Baong Fm. Ls. R R Mem Peutu Fm. S Bruksah Fm. Alur Siwah 5 Arun High Bampo Fm. High Jawa Deep 6 Lho Sukon Deep CL Sea Level Pre Tertiary Basement Malacca Shelf 20 Km 16X Exaggeration = Top Oil Window CL = Top Gas Window =Coastline 100 A' Early Miocene Belumai sandstone Play Miocene reefal carbonate Play Miocene Baong sandstone Play Mio - Pliocene Keutapang sandstone play Pliocene Seurula sandstone play Modified from Buck & Mc. Culloh (1994) Legend A A' Cross Section Location Bampo-Peutu Petroleum System Gas Discovery Oil Discovery A Bampo-Peutu Petroleum System 0. Barisan Mountains 20 Km 40 FO Asam Of Indo Strait of Malacca Coastline A'#20HYDROCARBON POTENTIAL#21LEMIGAS HYDROCARBON POTENTIAL HYDROCARBON EXPLORATION 100 Oil Companies in the North Sumatera Basin No. Company Block THAILAND 39 ENI KRUENG MANE LTD BULUNGAN PP 134 PT ZARATEX NV LHOKSEUMAWE 43 EXXON MOBIL NSO/NSO-EXT Sabang Lamren TRANSWORLD 156 SERUWAI Banda Aceh 134 P.7 Looksmawe 156 SERUWAI 45 EXXON MOBIL "B" P.27 44 EXXON MOBIL PASE Malaboh 126 P.8 P.25 80 Susch Kabu 25a Belawan Medan MALACCA STRAIT PT MEDCO E&P MALAYSIA 126 "A" NORTH SUMATERA MALAKA 132 TELAGA BINJAI ENERGI BINJAI JOB PERTAMINA - 60 GEBANG COSTA INTERNATIONAL P7 PERTAMINA EAST ACEH P27 PERTAMINA PERLAK WORKING AREA MAP (Status: 1 May 2008) P8 PERTAMINA POLENG P25 PERTAMINA NAD-1 P25a PERTAMINA NAD-2#22LEMIGAS HYDROCARBON POTENTIAL HYDROCARBON EXPLORATION D EXISTING SEISMIC SECTION S& WELLS MAP (PND, 2008) 100 Total: 43559 Km seismic lines 1031 wells The seismic sections and well data are available in Patra Nusa Data (PND)#23LEMIGAS 100 HYDROCARBON POTENTIAL HYDROCARBON EXPLORATION 5° 95" 96° 97° 98 NSA NANGRGE ACEH DARUSSALAM SUMATRA ISLAND Arun GAS & OIL FIELDS MAP (PND, 2008) NORTH SUMATRA LEGEND GAS OIL UNDEVELOP INDONESIAN BOUNDARY PROVINCE BOUNDARY 33 Oil & Gas fields. Almost of them are located in onshore areas INSET N W E S 50 Kilometr Challenge to find oil & gas in offshore area#24LEMIGAS DEPARTENEN ENERGI DAN SUMBER DAYA MINERAL DIREKTORAT JENDERAL MINYAK DAN GAS BUMI NAD 144.42 113.34 SUMATERA UTARA CADANGAN MINYAK BUMI INDONESIA (STATUS: 1 JANUARI 2008) SUMATERA TENGAH 4.163.75 NA TUNA 414.03 KALIMANTAN 765.75 58.02 SUMATERA SELATAN 852.48 SULAWESI JAWA BARAT 596.81 JAWA TIMUR 913.09 CADANGAN MINYAK BUMI (MMSTB) DEPARTEMEN ENERGI DAN SUMBER DAYA MINERAL DIREKTORAT JENDERAL MINYAK DAN GAS BUMI ACEH (NAD) 3.71 1.32 SUMATERA UTARA 7.96 SUMETERA TENGAH 26.68 SUMATERA SELATAN HYDROCARBON POTENTIAL PAPUA MALUKU 60.83 15 RESERVES & RESOURCES Oil reserves: 257.76 MMSTB (Status 1 Januari 2008) Gas reserves: 5.03 TCF (Status, Januari 2007). TERBUKTI = 3,747.50 MMSTB POTENSIAL TOTAL 4,471.72 MMSTB = 8,219.22 MMSTB CADANGAN GAS BUMI INDONESIA (STATUS: 1 JANUARI 2007) NATUNA 53.06 KALIMANTAN TIMUR 21.49 JAWA BARAT 6.18 JAWA TIMUR 6.39 CADANGAN GAS (TSCF) SULAWESI MALUKU PAPUA 24.14 ©DIMICAS 2000. 01102007 TERBUKTI = 106.01 TSCF POTENSIAL = 58.98 TSCF = 164.99 TSCF TOTAL DJMIGAS 2008 SPECULATIVE REMAINING RESOURCES RESOURCES IN PLACE RECOVERABLE Oil (MMBO) 1,357.5 407.4 Gas (BCF) 3,067.1 1,355.7 Lemigas, 2007#25100 LEMIGAS SUMMARY The Larger Mergui - North Sumatera Basin is an extensional basin that initaly formed in Late Paleogene and mostly developed during Neogene time. The North Sumatera back-arc basin itself is the southern part of the larger Mergui - North Sumatera basin. ➤ Most tectonic elements in the North Sumatera Basin has relatively N-S and NW-SE trends as product of three tectonic events. Early Tertiary tectonism, Mid-Miocene Tectonism, and Plio-Pleistocene tectonism. The N-S trends represent Pre-Miocene Structures and the NW- SE trends are Post Miocene structures The Petroleum system indicates that the deeper sub-basins of the North Sumatra basin were suitable for kitchen area. Early hydrocarbon generation began in Mid-Miocene and critical moment occurred in Plio-Pleistocene. Generated hydrocarbon accumulated into available plays such as: Early Miocene Belumai sandstone Play Miocene reefal carbonate Play Miocene Baong sandstone Play Upper Miocene to Pliocene Keutapang sandstone play Pliocene Seurula sandstone play Today more than 14 Oil Companies have working areas in this basin, and most of oil & gas fields located in the onshore areas. Total hydrocarbon reserves recently are 257.76 MM STB oil and 5.03 TCF gas. There is still more opportunity to find oil & gas in this basin, especially in the offshore area#26TERIMA KASIH THANK YOU