Cased Hole Formation Connectivity Investigation Aids in Completion and Production Optimization: Offshore Malaysia Field

Abstract

Reservoir pressure is one of the key properties needed in formation characterization. In addition to reservoir fluid identification through pressure gradient, reservoir pressure measurement plays a vital role in evaluating reservoir connectivity. This understanding of reservoir connectivity will subsequently aid in reservoir management planning, including completion design optimization. Formation connectivity investigation is especially challenging in a cased-hole environment where unfavorable wellbore conditions prevented open-hole evaluations. This paper presents a case study in a Malaysia offshore field where formation pressure measurements behind casing were carried out to allow the investigation of formation connectivity which is required for completion design, production planning, and potential cross-flow for zone commingling strategies. Cased-hole formation tester was used to evaluate formation pressure in the target zones where two wells were drilled in the same field. The formation pressure acquired was subsequently utilized in completion design and perforation planning based on reservoir connectivity. The pertinent questions about this field have been answered and helped in making the best possible connection between the wellbore and production optimization. This application of formation pressure measurement behind casing has been proven to add value to the completion design optimization process. Lessons learned supported by field data will be presented along with recommended cased-hole reservoir connectivity investigation techniques and strategy.