A case study in the local estimation of shear-wave logs

Brian H. Russell, Laurence R. Lines, Daniel P. Hampson

In this case study, we utilize the techniques of multi-linear regression and cross-validation to develop a relationship between shear-wave logs and a suite of other well log curves. This relationship is then used to predict pseudo shear-wave log curves in wells that do not contain shear-wave information. The relationship that is derived in this study can be seen as an improvement on the standard linear relationship used to predict shear-wave logs (Castagna et al., 1985). However, it is important to note that the relationship derived here is strictly valid only within the area of study. We therefore feel that this work presents an approach to building local relationships within specific areas of study, rather than presenting a universal equation that can be used everywhere.