CONTENTS 1-Khmere Basin 2-Regional Geology Khmer Basin 3-Regime Tectonic 4-Seismic Database -a/ Acquisition Data -b/ Prospect Angkor -C/ Cross Section Seismic 5-Play Type -a/ Play Schematic -b/ Structure Map 6-Reservoir rock Khmer Basin -a/ Petrophisical Result -b/ Petroleum Geology Reservoir rock -c/ Porosity and Permeability in Reservoir rock -d/ Hydrocarbon Saturation
KHMER BASIN MAP
REGIONAL GEOLOGY IN KHMER BASIN A half graben which was formed by right lateral trans- tensional movement cause by exstrusion of Indochina during Early Oligocene The axis of the basin is North-South and the eastern limit is basin-bounding bounding fault thrown to the west. The Oldest formation in the basin is Early Oligocene clastic. The basin center is located around southern part of Block III, which depth is about 6000-7000 meters. STRATIGRAPHY (depositional environment) Late Miocene Pliocen Pleistocene Middle Miocene Fluvial Coastal plain Early Miocene Oligocene : Shallow marine : Fluvial Coastal plain : Fluvial Lacustrine : Alluvial fan near basin
SESMIC DATA BASE Block I and II Operator : Enterprise Oil 2 D -58 lines Block III-Operator : Campex 2 D -48 lines Block V I Operator : Premier Oil 2 D -43 lines
ANGKOR-1 1 PROSPECT DEPTH MAP
CROSS SECTION LINE E92 CBO6-077 ANGKOR-1 Lower Oligocene
REGIME TECTONIC The Khmer basin was completed tectonic in relation with India Erasia continental collision and Exstrusion of Indochina : - AGE (Eocene?) - Oligocene. - Stress - Right lateral trans-tensional tensional - Play : - Late Miocene -Oligocene - Late Miocene-Plio Plio- Pleistocene - Middle Miocene - - Lower Oligocene - : Shallow marine : Channel sandstone : Channel sandstone Lacustrine sandstone.
ACQUISITION DATA 2D SEISMIC During 1992 Enterprise acquired 7344 km of 2D seismic data, Split as follow:3079 km in block I,3352 km of regional data in block III and II. The data was acquired by HGS and provided a 2.5 x 2.5 km grid over block I and II,and a 20 x 20 km grid over block III and IV. The data was processed by Ensign between June and October 1992. In addition, Enterprise traded seismic data with Campex to gain a further 3600 km of 2D data over block III. By the end of 1998 Woodside Petroleum(Australian Company) has awarded PSCs for offshore blocks 5 & 6. Woodside acquired 5000km of 2D seismic lines.
3D SEISMIC The 2D dataset was considered in adequate for detailed mapping of complex structure found along the margins of the Khmer Basin. The way forward was identified to be the acquisition of the 3D survey was part of the work commitment for a first license extension. The 3D survey was acquired by the vessel M/V Western between 9 October 1994 and 2 December 1994. It covered 860 km2 and Comprised over 35,000 subsurface line km of data, creating normal 40 fold cube of data, with a crossline separation of 25 m and in line spacing of 12.5 m. As a result, a total 9 wells were drilled and about 13675.150 km of 2D seismic lines and 1050 km2 of 3D seismic survey acquired and processed in these offshore blocks by those companies during 1990-1997.
STRUCTURE MAP KHMER BASIN
PLAY TYPE Well Name Koah Tang-1 Koah Pring-1 Apsara- 1 Poulo wai-1 Devada-1 Da-1 Play Description first fault trap from basin center four way dip closure basin center synthetic/antithetic fault trap near basin synthetic/antithetic fault trap at western of basin synthetic/antithetic fault trap at east of basin synthetic/antithetic fault trap at south of basin
DESIGNTED PLAY TYPES
PLAY SCHEMATIC
Block Name Exploration history in Cambodia FIRST STAGE (1971-1975) Operator Wells Result KOMPONG SOM ELF H-1 L-1 B1-1 Dry Dry, but untested closure remain deeper Dry SECOND STAGE (1991-1998) Block Name Operator Wells Result BLOCK IV PREMIER IDEMITSU Koah Tang-1 Koah Pring-1 Oil discovery in Upper Oligocene Dry BLOCK III CAMPEX IDEMITSU Apsara-1 Devada-1 Poulo Wai-1 Oil discovery in Upper Oligocene Dry Dry BLOCK I/II ENTERPRISE Angkor-1 Da-1 Preah Khan-1 Bayon-1 Oil & Gas discovery in Lower Oligocene Dry Dry Dry BLOCK V/VI WOODSIDE Started in 1998,Seismic option
RESERVOIR KHMER BASIN Reservoir rock khmer basin are potencial developed in stacked sandstone sequence,which are anticipated to be developed fluvial channel sandstone in stacked channel sandstone in stacked channel complexes fluvial delta and fluvial lacustrine sediment. Commercial Reservoir in khmer basin through rang 12-20 20 m in thick, average thickness is 5.5 m. A typical discovery consist 8-208 m pay sand with on aggregate net thick net thickness of 50 m over interval 700 m. Reservoir quality effective hydrocarbon reservoir within the Khmer basin are sandstone of late Oligocene to Early Miocene age.
ISOPACH POSOSITY MAP Top sequence III and IV
Depth vs Porosity KHMER BASIN
Leang-3
OFFSHORE CAMBODIA PETROPHYSICAL RESULT Age Reservoir Gross Th m Net Sand m NTG % Porosity % Angkor: Late Miocen Mid Miocene Low Miocene Early miocene 394 611 710 1389 99,5 119,9 275,2 137 25,3 196,5 38,8 10,1 30 23,8 10,9 10,1 Apsara: : Late Miocen Mid Miocene Low Miocene Early miocene 350 164 863 1134 14,2 10,2 107,9 73,5 4,1 6,2 12,5 6,5 37,4 25,8 16,5 16,9 Bayon: : Late Miocen Mid Miocene Low Miocene Early miocene 365 605 1070 989 58,4 91,4 222,8 92,5 16 15 21 92,5 28,3 14,5 19,4 14,3 Da : Late Miocen Mid Miocene Low Miocene Early miocene 557 571 666 758 41,9 88,5 109,9 46,3 16,3 15,6 16,5 6,1 21,7 24,1 22 15,4 Devada: : Late Miocen Mid Miocene Low Miocene Early miocene 228 112 630 821 66,1 27 10,5 88,2 22,3 29 22, 16,7 26 29 27,9 17,6
PRTROLEUM GEOLOGY RESERVOIR ROCK Potential Reservoir Rock in offshore Cambodia Formation Reservoir Quality Discovery Mid Miocene Fluvial channel sand good Low Miocene Fluvial channel sand good Angkor-180B/D Lacustrine sandstone. Oligocene Fluvial channel sand Fair poor Koah tang 1179 B /D Lacustrine sandstone Poor Fair good Pre- tertiary sand Unknow
CORRELATION WELL KHMER BASIN PARAMETER RESERVOIR Interval depth Gross sand Thickness Net Pay (m) (m) (m) LOCATION KAOH TANG -1 2500-2842 2842 324 11 APSARA -1 2525-2865 2865 340 19 ANGKOR -1 450-3100 650 15 BAYON -1 2545-3000 492 14 DA -1 2206-2692 2692 486 11.2
WELL OVERVIEW
Porosity and Permeability in Reservoir Rock The Oldest formation in the basin is (Late Eocene?) Early Oligocene clastic reservoir depression are characterized vertically and laterally.porosity and permeability due to basin evolution history, complex tectonic movement The petrophysical property distribution formation of Khmer Basin Region Parameter Angkor-1 Sequence VII Da-1 Sequence V Deveda-1 Sequence IV Poulo wai-1 Sequence III Apsara-1 Sequence II Porosity Q % 27 23,3 14 13 12 Permeability k md 750 400 4 1 0,1
Depth vs Porosity Function Based on Angkor-1 &Apsra-1 Well Data
Depth m SUMMARY OF UNSTEADY-STATE STATE GAS OIL RELATIVE PERMEABILITY RESULT Permeability k md Porosity % water saturation % oil Saturation % 2028,5 0 745 25,2 15,9 81,1 2030,60 768 24.5 17,4 82,6 2775,50 17,5 15,2 32,4 67,6
Hydrocarbon Saturation
POROSITY& PERMEABILITY RELATIONSHIP