A Method to Diagnose Depletion, Skin, kh, and Drive Mechanism Effects Using Reservoir Monitoring Data

摘要

The use of permanent sensors provides a continuous sourceof downhole pressure measurement throughout the life of thewell. Moreover, multiphase flowmeters provide simultaneousflow rate measurements. The significant amount of dataproduced by these sensors has added a new dimension totraditional well test data interpretation techniques. This newdimension is life -of-well time. During the life of the well,permanent-gauge data and flow rate measurements areaffected by several dynamic factors including changes inreservoir pressure, skin, permeability-thickness (kh), andreservoir drive mechanism. A major challenge facing theindustry today is how to diagnose and respond to the effect ofeach of these factors. In other words, it is important to knowwhether a change in measured downhole pressure or flow rateis caused by depletion, changes in skin, kh, or drivemechanism.This study investigates the effects of the above-mentionedfactors in two fields in the Gulf of Mexico area. In addition,experience and lessons learned from numerous wells andfields equipped with permanent sensors have been used todevelop a diagnostic method. This method uses key reservoirand well performance indicators to derive techniques todistinguish between the effects of depletion, skin, kh and drivemechanism. Best practices in the collection of flow rate andpressure data with suggestions for near-future improvementsare included.