Marine multicomponent seismology made its semicommercial emergence in the North Sea in the autumn of 1996. This technology involves the recording of shear (S) -waves, in addition to conventional compressional (P) -waves, by deploying sensor packages (containing hydrophones plus three-component geophones) on the seafloor. New processing algorithms have been developed to process these data properly. The major uses of this type of data are (1) to image beneath gas clouds and chimneys; (2) to better infer Lithological and pore-fluid information some distance away from wells; and (3) to image beneath high-seismic-velocity bodies, such as salt and basalt masses.