Onshore Examples and Applications
Applications and examples of multicomponent seismic technology across onshore prospects are assembled in this chapter. Because dipole sources that directly contact earth strata can be used in land-based seismic fieldwork, land-based multicomponent studies involve some S-wave modes that cannot be replicated in marine environments. Specifically, the SH-SH mode is unique to onshore multicomponent applications, and for all practical purposes, so is the SV-SV mode. An SV-SV mode can exist in marine data only when a hard seafloor causes a P-to-SV mode conversion directly at the base of the water column. Even though SH sources cannot be used in offshore areas, most of the multicomponent applications that are illustrated onshore also can be implemented across marine prospects.
Data examples in this chapter span several decades of investigation. Several early S-wave experiments are quite valuable for demonstrating basic principles and are included in the portfolio of rock and fluid applications assembled in this chapter so the work of first-generation proponents of S-wave technology can guide those of us who follow in their steps. The compilations of multicomponent seismic applications prepared by Stewart et al. (2003) and by Hardage (2010) are recommended reading to complement the material presented in this chapter.