Tertiary tectonics and sedimentation in the Salin (fore-arc) basin, Myanmar

Conference · Fri Mar 01 04:00:00 EST 1991 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:7171397

Trevena, A S; Varga, R J ^[1]; Collins, I D; Nu, U ^[2]

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1. Unocal Science and Technology Division, Brea, CA (United States)
2. Unocal Myanmar, Yangon (Burma)

Salin basin of central Myanmar is a tertiary fore-arc basin that extends over 10,000 mi{sup 2} and contains 30,000+ ft of siliciclastic rocks. In the western Salin basin, Tertiary deltaic and fluvial formations contain thousands of feet of lithic sandstones that alternate with transgressive shallow marine shales. Facies and paleocurrent studies indicate deposition by north-to-south prograding tidal deltas and associated fluvial systems in a semi-restricted basin. Presence of serpentinite and volcanic clasts in Tertiary sandstones may imply that the basin was bounded to the east by the volcanic arc and to the west by a fore-arc accretionary ridge throughout much of the Cenozoic. Salin basin is currently defined by a regional north/south-trending syncline with uplifts along the eastern and western margins. Elongate folds along the eastern basin margin verge to the east and lie above the reverse faults that dip west; much of Myanmar's present hydrocarbon production is from these structures. Analogous structures occur along the western margin, but verge to the west and are associated with numerous hydrocarbon seeps and hand-dug wells. These basin-bounding structures are the result of fault-propagation folding. In the western Salin basin, major detachments occur within the shaly Tabyin and Laungshe formations. Fault ramps propagated through steep forelimbs on the western sides of the folds, resulting in highly asymmetric footwall synclines. Stratigraphic and apatite fission track data are consistent with dominantly Plio-Pleistocene uplift, with limited uplift beginning approximately 10 Ma. Paleostress analysis of fault/slickenside data indicates that fold and thrust structures formed during regional east/west compression and are not related in any simple way to regional transpression as suggested by plate kinematics.

• OSTI ID: 7171397
• Report Number(s): CONF-910403--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Journal Volume: 75:3
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
AGE ESTIMATION
APATITES
ASIA
BURMA
CENOZOIC ERA
DEVELOPING COUNTRIES
FISSION TRACKS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOLOGY
MINERAL RESOURCES
MINERALS
PARTICLE TRACKS
PETROLEUM DEPOSITS
PETROLEUM GEOLOGY
PHOSPHATE MINERALS
PRODUCTION
RESOURCES
SEDIMENTARY BASINS
SEDIMENTATION
STRATIGRAPHY
TERTIARY PERIOD