Deep Water Production Improvement through Proactive Reservoir Management and Conformance Control

Deep water fields are commonly subject to high development cost, challenging topside and subsurface issues and uncertainties. The level of heterogeneity, compartmentalization, fault intensity, reservoir connectivity, pressure and flow communication across the field, sand/fine production, wellbore stability are commonly less well understood at the time the development decision is made. The reservoirs may also consist of very thin beds to thick blocky sands and the reservoir properties can vary significantly both laterally and vertically throughout the field. Pressure maintenance and water/gas injection can be part of the selected development strategies from day one. Due to the high uncertainties and development cost, both producers and injectors might be pragmatically commingled across various reservoirs with no additional sandface control and operational flexibility. Reservoir management strategies may rely on field/reservoir level voidage replacement ratio (VRR) control with no additional selectivity and control on water/gas injection. This strategy combined with the above mentioned uncertainty issues can potentially lead to injection conformance issues and reduced recovery factor due to sub-optimal sweep efficiency at the sand by sand levels. A deep water example has been studied in this work showing the conformance issue and uneven pressure distribution confirmed by different PLT campaigns and MDT pressure surveys for various reservoirs under VRR control. In this paper, the above challenges and reservoir management (RMP) requirements combined with the concerns of the optimized water flooding in a complex deep water field in Malaysia have been studied and discussed. The application of the proposed guidelines and strategies for proactive reservoir management and conformance control showed potential for significant improvement in sweep efficiency optimization and hydrocarbon recovery improvement in this deep water field.