Pressure-Pressure Deconvolution Analysis of Multiwell-Interference and Interval-Pressure-Transient Tests

Abstract

Summary This paper investigates the use of pressure-pressure (p-p) deconvolution for interpretation of conventional multiwall-interference and wireline-formation-tester (WFT) interval pressure-transient tests (IPTTs). The investigation is limited to interference tests for which only a single source/sink well exists in a single-layer system. It is shown that the recent deconvolution algorithms developed for pressure-rate (p-r) deconvolution based on the same assumptions (i.e., a single source/ sink well) can also be used for performing p-p deconvolution by simply replacing the rate data in p-r deconvolution algorithms by the pressure data recorded at a source/sink location or at one of the observation locations. We apply p-p deconvolution to both synthetic and field-transient test data sets from IPTTs and multiwall-interference tests. Specifically, we investigate the applicability of p-p deconvolution for inconsistent data sets, where wellbore storage and skin may change from one flow period to another one. The results show that the impulse functions deconvolved from p-p deconvolution have signatures for various flow regimes (e.g., radial, spherical, linear) that are similar to from p-r deconvolution except from the pseudosteady-state (pss)-flow regime. Therefore, p-p deconvolution can also be used for model identification in the similar way based on p-r deconvolution algorithms, without requiring the flow-rate information.