Abstract

During the second quarter of 1991, Asamera was given approval by Pertamina - BPPKA to carry out the full scale development of the Bentayan field located in the central area of Asamera's Corridor Block concession in South Sumatra. This marked a significant milestone in what has been a long road to development.

The Bentayan field was discovered in 1932 by Bataafsch Petroleum Mij. N.V., now Royal Dutch Shell. The discovery well, Bentayan-1, encountered a 19.1°API, waxy crude in the Talang Akar Formation. Half a century later, by which time the field had passed through several operators and thirteen (13) wells had been drilled, Bentayan remained undeveloped. Several studies by different operators had indicated that the economics for developing this field were marginal at best. These studies assumed that: a high well density (10-30 acre well spacing) would be required; the in-situ viscosity was too high; production rates would be too low; early water breakthrough would occur; and, there would be severe surface handling problems due to the high pour point (112°F) of the crude.

In order to prove the feasibility of development at Bentayan, Asamera initiated a pilot scheme in 1985, which ultimately involved the drilling of eleven (11) additional wells and the expansion of existing facilities. An important aspect of this pilot was the use of light crude from Pertamina's Jambi area fields blend crude. Information from this pilot demonstrated that the previous assumptions which had militated against full scale development were invalid. Data collected during the pilot phase demonstrated that actual field performance was significantly better than anticipated, which in turn led to the decision to fully develop the field.

This paper reviews the pilot production scheme, examines the data collected, outlines the full development plan currently underway, and outlines possible future initiatives to enhance production.