Evaluation and application of the transient-pulse technique for determining the hydraulic properties of low permeability rocks: Part 2: Experimental application

M. Zhang; M. Takahashi; R. Morin; T. Esaki

doi:10.1520/gtj11127j

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Evaluation and application of the transient-pulse technique for determining the hydraulic properties of low permeability rocks: Part 2: Experimental application

M. Zhang·M. Takahashi·R. Morin·T. Esaki

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Abstract

In Part 1 of this study, the general solution to the transient-pulse test (Hsieh et al. 1981) was extended to evaluate quantitatively the transient variations in hydraulic head and the corresponding distributions of hydraulic gradient within a test specimen. In addition, the conditions and the validity of using the expression proposed by Brace et al. (1968) to compute the low permeability of a rock specimen from a transient-pulse test were examined. Some theoretical considerations related to the optimal design of a transient-pulse test were also discussed. Part 2 presents a relatively general and convenient approach for determining not only the hydraulic conductivity and specific storage of a specimen directly from a transient-pulse test, but also the compressive storage of the fluid reservoirs. The accuracy and efficiency of this method are demonstrated through (1) the comparison of the compressibility of the fluid-reservoir (permeating) system back-calculated from the transient-pulse tests with the value obtained from calibration tests, and (2) its application to a series of experimental studies designed to investigate the effects of confining pressure on the hydraulic properties of Shirahama sandstone and Inada granite, two rock types available widely in Japan.

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M. Zhang, M. Takahashi, R. Morin, T. Esaki. 2000. Evaluation and application of the transient-pulse technique for determining the hydraulic properties of low permeability rocks: Part 2: Experimental application. https://doi.org/10.1520/gtj11127j

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