Solution of salt from a shallow Upper Permian formation in parts of Western Anadarko Basin was observed to produce a pronounced and relatively abrupt velocity change, such as to cause over 300 feet of seismic relief error across a distance of less than three miles. Core-hole velocity shooting and velocity profiling were used in the study of the effect of salt solution. The theory, methods, and results of the velocity profiling program are described. The core-hole velocity data indicate that in the area several environments are present which involve different types of velocity alteration by ground water activity. This kind of phenomenon is considered to be of general significance and related to the spurious representation of surface topography sometimes observed in seismic structural maps.