Natural/induced fracture orientation and permeability anisotropy (Kx:Ky) are two critical parameters required for understanding highly fractured anisotropic reservoirs such as the case in the Devonian shales.

A detailed geologic/engineering test was performed on the Chattanooga shale in eastern and southeastern Kentucky. Early results of tiltmeter responses were correlated with pre- and post-stimulation interference and pulse test results. Tiltmeter responses were corrected for uplifts induced by pressure transient during the frac treatment. In addition, corrections were applied to pulse test results for skin and wellbore storage.

Early studies of the pre- and post-stimulation interference tests indicated major permeability trends of N18°E and N32°W, respectively. In addition, a post-stimulation permeability anisotropy of 20:1 was calculated. Results of initial tiltmeter pressure response analyses indicated an induced fracture orientation of N30°E and a possible second orientation of N30°W.

Keywords:
pressure transient, drillstem testing, interference pulse-test result, upstream oil & gas, chattanooga shale, pressure response, interference test, stimulation, chandler, permeability
Subjects:
Hydraulic Fracturing, Formation Evaluation & Management, Drillstem/well testing
Copyright 1989, Not subject to copyright. This document was prepared by government employees or with government funding that places it in the public domain.
You can access this article if you purchase or spend a download.