Mode converted shear waves have been shown to allow overpressure prediction in media where primary wave acquisition is inhibited by gas and fluid effects. This method proceeds through analysis of converted-wave moveout, and a long standing relationship between differential stress and changes in primary-wave velocity is modified in this prediction. Though empirical evidence from laboratory experiments and field experiments supports the stress/shear wave velocity relationship, a theoretical justification has been developed. In this paper, the original relationship is modified formally, and the overall procedure is outlined.
View full article as PDF (1.49 Mb)