Analysis of overpressure zones at the southern margin of the Baram Delta Province and their implications to hydrocarbon expulsion, migration, and entrapment

Conference · Fri Jul 01 00:00:00 EDT 1994 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:7016866

Mantaring, A; Matsuda, F; Okamoto, M ^[1]

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1. Idemitsu Oil Exploration Co., Ltd., Sarawak (Malaysia)

The Baram delta oil and gas province covers a major part of the onshore and offshore areas of northern Sarawak, Malaysia, and Brunei. Thick marine to deltaic sediments of late Eocene to Pleistocene age were rapidly deposited in the basin, resulting in widespread abnormal formation pressures. Overpressure zones are normally encountered within thick marine-deposited claystone intervals occurring below and/or just at the basal part of major oil and gas accumulations in the offshore areas of the Baram delta. Because of drilling hazards, the onset of overpressuring is regarded as an arbitrary economic limit for oil exploration. In onshore Sarawak, the southern margin of the Baram delta province contains thick late Eocene to Miocene (Cycle I-V) sediments deposited and uplifted in the latest Pliocene. Abnormal pressure zones have been encountered in three different settings viz.: (1) undercompacted claystone predominant intervals, (2) uplifted reservoir sands with hydrocarbons, and (3) hydrodynamically pressured shallow sand intervals. A unique overpressure zone, which occurs below stacks of hydrostatic and permeable coastal-deltaic sands, has been observed.

• OSTI ID: 7016866
• Report Number(s): CONF-940803-; CODEN: AABUD2
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 78:7; Conference: American Association of Petroleum Geologists (AAPG) international conference and exhibition, Kuala Lumpur (Malaysia), 21-24 Aug 1994; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
BRUNEI
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
MALAYSIA
RESERVOIR PRESSURE
SAFETY
WELL DRILLING
ASIA
DEVELOPING COUNTRIES
DRILLING
GEOLOGIC DEPOSITS
MINERAL RESOURCES
RESOURCES
020300* - Petroleum- Drilling & Production
030300 - Natural Gas- Drilling
Production
& Processing
020200 - Petroleum- Reserves
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030200 - Natural Gas- Reserves
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