Permanent Gauge Pressure and Rate Measurements for Reservoir Description and Well Monitoring: Field Cases

This paper presents a procedure for interpreting data acquired with permanent downhole pressure sensors in association with surface or downhole rate measurements. The usefulness of this data source in reservoir description and well performance monitoring is illustrated. Unlike previously published examples, the interpretation is based on the analysis on a stream of data acquired over large periods of time, thus utilizing the continuous nature of the measurements. Three field cases are presented using the pressure and rate data in decline-curve analysis for wells with a variable downhole flowing pressure, and through more sophisticated models that are similar to the ones used in well test analysis. Because such interpretation is conducted while continuing production, it is particularly well suited for a well or group of wells under extended testing, which are equipped with downhole gauges and are flowing through surface separation and metering systems. Wells completed with both permanent downhole rate and pressure measurements are also ideal candidates for this type of analysis. Finally, the influence of the pressure sensor long term drift and the rate measurement error on the interpretation results and future forecasts are investigated.