Abstract
Excessive water production and unbalanced sweep in a water flooded reservoir can significantly impact oil production and increase water handling expenses, jeopardizing the overall economic recovery of hydrocarbon within the field. The objective of this paper is to provide a review of various integrated water management techniques successfully implemented in a carbonate field in Saudi Arabia, balanced under the critical monitoring eye of a systematic strategic surveillance program deployed to assess sweep efficiency across the field.
Complex networks of super permeable streaks and sub vertical fractures highly influencing fluid transport media within the subsurface characterize this carbonate reservoir. Understanding fluid flow mechanism in this heterogeneous gravity dominated reservoir is a predominant factor influencing the various approaches designed to manage water production in the field. The key management strategies that have been introduced are horizontal sidetracking of existing vertical wells at the top of reservoir, rigless water shut-off jobs and employing cyclic production mode for wells with very high water cut. In addition, Inflow Control Device (ICD) completion technology is being deployed within lateral sections that have encountered flow dominating geological features, such as fractures or super-K, providing a practical, innovative solution for an effective homogenized flow distribution along the lateral intervals. Collectively, these employed practices have been found successful in substantially reducing water production and improving oil recovery as supported by field data.
Concurrent with these water management strategies, sweep conformance and flood front movement are regularly monitored by conducting a rigorous Strategic Surveillance Master (SSM) plan across the whole field. The results from saturation and production profile logs confirm efficient vertical and areal sweep conformance and ensure the effectiveness of the integrated water management strategies employed in the field.
