Publications

The Musi Platform and Palembang High are structural elements in the South Sumatra Basin, that have become more important targets in future exploration activities. In the South Sumatra Basin, oil and gas are produced from several reservoirs such as the Talang Akar sands, Baturaja limestone and Palembang sands as well as from fractures in the Pre-Tertiary basement. The hydrocarbon source rocks are believed to be the Paleogene lacustrine shales of the Lahat/Lemat formation, and the fluvio-deltaic to marginal marine Talang Akar shales and coals.The geochemical reevaluation of crude oil and condensates from 41 samples in the basin, combined with data from the newly discovered fields in the Palembang High and Musi Platform established three genetic oil groups in the areas, i.e. marine, lacustrine and deltaic oils.In this paper it is further shown that deltaic oils can be divided into two different facies, i.e. marine and fluvial deltaic types. Oil in the Palembang High area apparently belongs to . the jluvial deltaic type. Indications are that this oil represents a mix of the two typical oils from the southern and northern portions of the Palembang High. Marine influenced oils, on the other hand, can be divided into two facies, i.e. marine shale and marine carbonate oils. Marine carbonate oil was found in condensate samples taken from the Pre-Tertiary Basement fracture in the Musi Platform. The new evidence described in this paper may open new exploration opportunities in these areas.