STATIC CORRECTIONS FROM SHALLOW-REFLECTION SURVEYS

Shallow-reflection data from the Texas panhandle illustrate a real geologic situation with sufficient variability in the near surface to significantly affect seismic signal reflected from depths commonly targeted by conventional reflection surveys. Synthetic data approximating a conventional reflection survey combined with a weathered-layer model generated from shallow-reflection data show the possible dramatic static effects of alluvium. Shallow high-resolution reflection surveys can be used both to determine the severity of intra-array statics and to assist in the design of a filter to remove much of the distortion such statics cause on deeper reflection data. The static effects of unconsolidated materials can be even more dramatic on S-wave reflection surveys than on comparable P-wave surveys. -from Authors