Abstract measurement of formation permeability using stoneley waves from an LWD acoustic tool

by Tor Eiane, Baker Hughes

Abstract

Recent development of LWD acoustic technology has stimulated interest in measuring permeability using LWD acoustic tools. A feasibility study on this subject has been performed. Theoretical modeling has been made to stimulate Stoneley wave propagation and analyze the wave’s characteristics in the LWD environment. The analyses show that the presence of an LWD tool in the borehole substantially increases the sensitivity of the Stoneley wave to formation permeability, as compared to the WL scenario. The much enhanced sensitivity allows for using the Stoneley waves to measure formation permeability in the LWD environment. An adverse effect in the LWD, besides various drilling noises, is the decentralization of the LWD tool during drilling. This effect can adversely affect the velocity of the stoneley wave traveling along the borehole. The use of stabilizers at the ends of LWD tool helps reduce the tool decentralization effect. Field data analysis results validate the theoretical analysis. The results of this study establish the feasibility of permeability measurements using Stoneley waves acquired by an LWD acoustic tool.

Tor Eiane, CV

Tor Eiane is currently working as Formation Evaluation Business Development Manager for Baker Hughes. Tor has been in the industry 18 years, all within Baker Hughes. He spent several years as a logging engineer prior to his current role. His expertise is in acoustics and magnetic resonance.