Impact of Passive Microseismic Monitoring on Business and Reservoir Management: Examples from Oman

Passive microseismic monitoring is a tool used in petroleum industry to mitigate risk and assess reservoir integrity, and track fluid movements. Two case studies of the usefulness of microseismic monitoring in reservoir management and business decisions are presented in this paper. The first example is from a permanent reservoir monitoring of water flooding in an oil reservoir. Microseismic observations indicated the possibility of reservoir fracturing by high water injection from a nearby injector. Based on the microseismic interpretation the field reservoir engineer was instructed to lower water injection as to avoid reservoir fracturing and hence potentially lower water cut. In the second example, the importance of using microseismic technology for hydraulic frac monitoring is illustrated. The microseismic interpretation showed that the frac was not confined to the targeted interval and has grown upward where the next frac stage was planned, resulting in an inefficient frac job. The decision was made to re-visit the second frac stage after exploring optimized new frac designs.

Overall, the two examples show the importance of having real time microseismic information and joint decision making between surveillance geophysicists and field management.