Deconvolution of Variable-Rate Reservoir-Performance Data Using B-Splines

This work presents the development, validation, and application of a deconvolution method that uses B-splines to analyze variable-rate reservoir-performance data. Variable-rate deconvolution is a mathematically unstable problem. B-splines represent the derivative of unknown unit-rate drawdown pressure, and numerical inversion of the Laplace transform is used in this formulation. When significant errors and inconsistencies exist in the data functions, direct and indirect regularization methods are used (i.e., mathematical "uniformity" processes). The new deconvolution method has broad applicability in variable-rate/pressure problems and can be implemented in typical well-test and production data analysis.

View a Synopsis of SPE 95571.

This article, written by Technology Editor Dennis Denney, contains highlights of paper SPE 95571, "Deconvolution of Variable-Rate Reservoir-Performance Data Using B-Splines," by D. Ilk, P.P. Valko, SPE, and T.A. Blasingame, SPE, Texas A&M U., prepared for the 2005 SPE Annual Technical Conference and Exhibition, Dallas, 9-12 October. The paper has not been peer reviewed.