Publications

This paper presents an approach in developing reservoir surveillance plan in the early production phase of Banyu Urip field. It describes how reservoir surveillance plan is built to acquire information to reduce reservoir uncertainties, while remain flexible according to reservoir management objectives. The final objectives are to establish effective and cost efficient surveillance activities to maximize recovery. Banyu Urip reservoir is a steep flanked carbonate structure with oil column sandwiched by gas cap and aquifer. The full scale production just started recently in 2015. In this type of reservoir system, the key to optimize rate and maximize recovery is better understanding of reservoir behavior and well performance. Meanwhile, in the early phase of production very limited reservoir information is available and the major uncertainties are in place: gas cap / aquifer size and strength, contacts movement, and excess permeability distribution. To support reservoir management, those uncertainties have to be unfolded by obtaining more information from systematic approach called reservoir surveillance plan. Banyu Urip reservoir surveillance plan is developed to document list of reservoir uncertainties, then to acquire required reservoir data to reduce the uncertainties by justifying value of information, and to define evaluation tools. Reservoir data are available in form of cased-hole logs, well tests, and downhole pressure gauge measurement. Banyu Urip reservoir surveillance plan is not only a tool to gain valuable reservoir information, but also way to communicate monitoring activities with operations and government.