The Kolo Creek field is a 5 × 10 km (3 × 6 mi) size, faulted, rollover structure with the E2.0 reservoir as the main oil-bearing sand. The reservoir is a 200 ft (66 m) thick, complex, deltaic sandstone package with a 1.9 tcf size gas cap underlain by a 200 ft (66 m) thick oil rim containing some 440 × 10⁶ bbls STOIIP. The sand is penetrated by 34 wells, 25 of which are completed as producers. Nine of the producers have been closed-in for excess gas production.

During the first two years of production (1973 to 1975), a 7% (350 psi, 2,400 kPa) decline from the initial reservoir pressure was associated with a cumulative oil production of 4.5% (20 × 10⁶ bbls) of STOIIP. To date, 16% (72 × 10⁶ bbls) of STOIIP has been produced with an attendant 16% (800 psi, 5,500 kPa) drop in pressure. A reservoir engineering study, based on the early pressure decline, led to the implementation of a water injection scheme for which, so far, 5 injection wells have been drilled. Immediately prior to the initial phase of the scheme, cores were taken in two wells. These cores, side wall samples from other wells, and the detailed correlation made possible by the denser well pattern have resulted in a realistic geological model. It wil be demonstrated how this model will influence the optimal location of future injection and production wells based on the structural and sedimentological characteristics of the reservoir.

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