Abstract

An integrated reservoir study was conducted for the Suizhong 36-1 offshore oil field located in Liaodong Bay in the People’s Republic of China. Based initially on petrophysical, geological and reservoir engineering interpretations, the complex reservoirs of this field were analyzed using sophisticated geophysical interpretations to determine reservoir thickness, areal extent, porosities, and fluid saturations. Results of these interpretations were integrated into unique and complicated reservoir models which were used to generate optimum production and development plans for this giant oil field.

As this oil field is located offshore, special considerations were required to effectively and economically produce the heavy oils that saturate these formations, including secondary recovery operations. Further consideration was given in the reservoir model to accommodate production requirements including deviated holes, high initial production rates and special completion techniques for unconsolidated sands. The complex models constructed to simulate the multiple reservoir layers in a faulted environment were capable of predicting detailed reservoir fluid behavior and flow pattern characteristics for the field, which has up to 300 meters of total thickness and an areal extent of almost 30 square kilometers.

Based on the results of several reservoir models, accurate and concise projections regarding the reservoir’s development and expected future production potential were possible. A large pilot program and ensuing field development plan comprising a total of seven platforms with 85 producing and 89 injectors using a 5-spot waterflood pattern on 400-meter spacing was recommended. Development planning included timing of waterflood injection, platform development and production/injection initiation, well patterns and spacing, and rates of production and water injection to optimize recovery.