Summary

Lacustrine source rocks are an integral component of the petroleum systems of many riff basins, particularly in SE Asia. Perhaps the best known is the Brown Shale of Central Sumatra which is a phenomenally productive oil prone syn-rift lacustrine source interval.

Much has been published on the geochemistry of the Brown Shale of Central Sumatra, but very little on linking the sedimentology and palynology to lake morphology and basin evolution. Exposures of the Brown Shale at the Karbindo Coal Mine within the Paleogene Kiliran subbasin of Central Sumatra allow this, and represent an overall transgressive sequence from red beds (paleosols), through a reed swamp coal to a shallow lake setting superbly exposed over a 200m thick stratigraphic interval.

AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah