Abstract: Geoscience Technology Application to Optimize Field Development, Seligi Field, Malay Basin

Mohd. Shahrin Ahmed, Brian D. Wiggins

Integration of well log, core, 3-D seismic, and engineering data within a sequence stratigraphic framework has enabled prediction of reservoir distribution and optimum development of Seligi field. Seligi is the largest field in the Malay Basin, with half of the reserves within lower Miocene Group J reservoirs. These reservoirs consist of shallow marine sandstones and estuarine sandstones predominately within an incised valley. Variation in reservoir quality has been a major challenge in developing Seligi.

Recognizing and mapping four sequences within the Group J incised valley fill has resulted in a geologic model for predicting the distribution of good quality estuarine reservoir units and intercalated low-permeability sand/shale units deposited during marine transgressions. These low-permeability units segregate the reservoir fluids, causing differential contact movement in response to production thus impacting completion strategy and well placement. Seismic calibration shows that a large impedance contrast exists between the low-permeability rock and adjacent good quality oil sand. Application of sequence stratigraphic/facies analysis coupled with the ability to identify the low-permeability units seismically is enabling optimum development of each of the four sequences at Seligi.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994