Application of Streamlines in Natural Depletion Systems

This paper describes a methodology to identify bypassed oil in mature fields under a natural depletion drive mechanism, i.e., aquifer drive, using streamlines. For a reservoir system in a complex nonhomogeneous geological system, with multiple wells and many years of production history, the method leverages on well rate drainage pore volumes generated by a streamline numerical simulator. The methodology uses the concept of time-superposition by normalizing to rates the wells historical cumulative formation withdrawals to calculate and map historical drainage regions (HDR) on a well-by-well basis. Furthermore, it estimates the remaining, bypassed oil volumes in place from these drainage regions.