Publications

M field is one of oil and gas producer fields at Tarakan Block that has been produced since 1987. It produces from more than 70 fluvial-deltaic lenses layers in Tarakan formation. As the field already mature, finding new prospective layers become necessary to arrest production decline. However, there are several challenges emerge in optimizing this field production due to limited pressure reservoirs data which lead to high uncertainty in fluvial-deltaic reservoirs correlation. A new analytical method then being introduced to recognize the reservoir connectivity and update the log correlation. This analytical method comprises of two main steps: (1) understanding the movement of hydrocarbon contact in reservoir based on historical order of hydrocarbon contact at open-hole log combined with reservoir production performance, (2) confirming hydrocarbon depletion in reservoir by running neutron cased-hole log. After reservoir connectivity and correlation had been recognized and updated, new prospective layers are able to be identified. The implementation of this method is able to increase the workover candidates at M field. A commingle production scenario using electric submersible pump (ESP) is also being assessed and implemented to get optimum production. Three workover programs had been executed in 4th quarter of 2018 which then resulted in 1077 BOEPD initial gain. This paper will elaborate the integrated effort of reservoir optimization in a mature fluvial-deltaic reservoir, started from development geological concept, reservoir engineering analysis, production and completion scenario preparation, and concluded by the workover execution that finally able to nearly double up the field production.