Classical interference testing techniques are based on the superposition of the line source solution. The use of this method is limited by the precision and time resolution that is normally obtained when measuring the production rate in active wells. In the new technique proposed, the pressure signal is measured at the active well and it is used to accurately calculate its diffusion in the reservoir. The higher precision in pressure calculation at the observing well gives more resolution to the analyst and provides more confidence when evaluating local reservoir heterogeneities.

The new method and related equations are presented and applied to a field example where a five-spot injection pattern is evaluated for a future CO2 injection pilot project. The diffusivity distribution estimated from the interference tests agrees with the description of the advance of the injected water obtained from radioactive tracer techniques.

Keywords:
application, reservoir, new interference test method, pressure signal, interference testing, drillstem/well testing, attenuation, diffusivity, spe 28379, line source solution
Subjects:
Well & Reservoir Surveillance and Monitoring, Reservoir Characterization, Improved and Enhanced Recovery, Formation Evaluation & Management, Drillstem/well testing
Copyright 1994, Society of Petroleum Engineers
You can access this article if you purchase or spend a download.