Abstract: Reservoir Description: an Aid to Exploit Low Productive TS-5A2 Sand of Geleki Field, India

LAHIRI, G., A.D. MATHUR, S. JOSHI, A. KUMAR

The Miocene Tipam sands constitute the major hydrocarbon producing zones of the Geleki field. The field is located in the Upper Assam Valley within the platform areas of Assam-Arakan Basin, India. The Tipam sands have six units: TS-1 to TS-6. Out of which, the TS-5A sand is the most extensive reservoir. It has been further subdivided into TS-5A1 and TS-5A2 sands, separated by a thin shale. TS-5A1 sand is a good producer of oil while TS-5A2 sand yields little production.

Detailed characterization of TS-5A2 sand has been carried out through various core studies, seismic, logs, borehole images and pressure data. This is to delineate the better reservoir facies. Integration of these studies have led to the conclusion that the source of TS-5A2 sand is different from TS-5A1 sand and the sand body of TS-5A2 close to the channel axis has better reservoir quality. TS-5A2 sand has very low permeability and practically shows no improvement in permeability on acid test. Well bore damage is nil but there exists a vertical communication between the two sands through the shale. This provides an opportunity to exploit TS-5A2 sand as the production through TS-5A1 sand continues.

AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria