ABSTRACT: Sopa reservoir simulation: a new method for reservoir modeling using geological and geophysical approaches
Biantoro, Cecep1, Susanto B. Nugroho1, Budi
Tamtomo1, and Djoko Harsono2
(1) Pertamina, South Sumatra, Indonesia
(2) Schlumberger, Jakarta, Indonesia
This paper describes a new method for modeling a reservoir rock for simulation study with limited data using geological and geophysical approaches. The model is representative as validated by material balance from production data and historical reservoir performance matching.
Sopa field, a newly discovered oil reservoir in South Sumatra, Indonesia, will be put on production at the same time as the delineation drilling program is conducted. The reservoir is a carbonate reef, which is extremely heterogeneous. Meanwhile, an optimum development plan is needed to recover the oil efficiently without wasting the reservoir energy. The optimum development plan was obtained from various production scenarios evaluated using Eclipse numerical reservoir simulation. The construction of the reservoir model, however, has been limited by the data due to the limitation of the number of wells drilled into the structure in this early stage of the field development.
A new method has been developed to characterize the reservoir model using seismic attributes; i.e. the acoustic impedance which is correlated to geological concepts. The data are used to generate rock porosity and permeability distribution in the horizontal direction. These rock properties were calibrated using the log porosity and well test data. The log porosity data from ELAN was also used to describe the vertical distribution in the reservoir. However, since the number of log data is limited, this vertical distribution should be projected horizontally using the acoustic impedance map.
The model has been validated using material balance from the production data, and the results were in a close agreement. A minimum adjustment to the model during historical performance matching has indicated that modeling using geological and geophysical approaches is acceptable.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia