Patent ID: 6415648
Filing Date: 2002-07-09
Classification: G01V

Abstract:
A method for use in determining the permeability of rock within a subterranean formation surrounding a borehole, the method comprising the following steps:causing a compressional wave to propagate through the rock of interest in a borehole, said compressional wave propagating from a first depth location within the borehole; said compressional wave propagating through the rock comprising a slow compressional wave and a fast compressional wave; detecting information relating to the velocity of said slow compressional wave at a second location within the borehole that is different than said first location; said step of causing includes creating a pressure step at the first depth location to induce said compressional wave in the rock of interest; determining, using the velocity of said slow compressional wave, the permeability of the rock of interest according to: Î¶p22=-i&it;â€ƒ&it;Î·&it;â€ƒ&it;Ï†f&af;(Ï‰)&it;Ko&it;Î¶p12&it;Ï BKf&af;(Kb+4&it;G/3)