Pore volume compressibility (PVC) is an important rock parameter in weakly-cemented sediments common in the Gulf of Mexico. Appropriately implementing this in reservoir simulations can significantly impact projections of reserves recovery. Drawing on field case history examples, the talk will highlight the need to properly characterize this rock property early in field appraisal.

Preferred ways of measuring PVC are described. Approaches to upscaling measured laboratory measurements to field-scale reservoir simulations will also be discussed. The talk will describe how compressibility varies as a function of both the magnitude of the pressure change, and the time over which this pressure change occurs. This sometimes overlooked property of weakly-cemented sediments is important when attempting to reconcile measures of compressibility derived from different sources - for example, from wireline logging data, from well test analysis, or from earth-tides pressure measurements. The impact of early-time production response, and the differing reservoir stiffness seen during reservoir reflation is also described. The talk will conclude with a discussion on the need for fully-coupled reservoir simulation (where the rock- and reservoir-responses are solved simultaneously), as this is currently a new area of technology development.