Abstract

The Lalang field, located in the Malacca Straits, began producing oil from the Lower Sihapas sandstone formation in June 1984. The operator of the field is Hudbay Oil (Malacca Straits) Ltd. The development scheme consists of a total of 16 wells producing from 3 wellhead platforms. The produced fluids are separated on a central processing platform and oil export is via a captive tanker.

The field has a relatively complex geology due to the presence of several sand shale sequences and numerous sealing and non-sealing faults. A reservoir simulation study of the field was completed shortly after the field commenced production. The purpose of the study was to investigate methods of optimizing recovery from the field and to compare alternative well completion methods. The Eclipse reservoir simulator was used to model the field. This simulator can model both sealing and non-sealing faults quite accurately and the grid can be distorted to conform to the actual shape of the field, thus providing a very accurate geological representation.

This paper describes the techniques which were used to develop the reservoir model of a geologically complex field such as Lalang. The success of the approach is illustrated by comparing the model prediction to the actual field performance over the first two years of production.