Complex component analysis of shear-wave splitting: case studies

Abstract

Summary Complex component analysis has been applied to four shear-wave data sets: a four-component single-offset VSP in the Lost Hills, Kern County; a multi-offset single-source two-component VSP in the Paris Basin; a four-component reflection line in the Lost Hills; and an in-seam crosshole survey at German Creek Mine, Australia. In all cases, the polarization of the faster split shear wave (or channel wave) can be assessed from the colour-coded record sections of the seismic attributes. In particular, the source-independent coherent polarization on the colour sections of the complex components of in-line and cross-line sources allows the shear-wave polarization angle to be determined without need for rotation of the instrument and source axes. We conclude that complex component analysis can aid identification and estimation of shear-wave splitting from seismic sections, help stratigraphic interpretation, and simplify the processing sequence of multicomponent reflection data in the presence of anisotropy.