The Effect of Radially Varying Transmissivity on the Transient Pressure Phenomenon

Abstract

During reinjection of cooled geothermal fluid into a reservoir, chemical precipitation and other processes may occur changing the permeability of the aquifer. In general, the permeability becomes a function both of time and space. This will, of course, affect the injection well. Some attempts have been made to analytically predict the pressure response. The present paper describes our calculations which yield analytic expressions, in terms of a single integral, for a wide class of physically reasonable permeability functions. Results are presented for a few typical examples.