Mapping ultra-shallow 3-D structure: A geometric approach

A cost-effective geometric strategy for ultra-shallow 3-D seismic investigation has been tested in an area with clear angular unconformity outcrop. Three crossed standard CMP survey lines were recorded with single 100-Hz geophone group. We applied common processing techniques to the entire data set before simulating 3-D structure. To implement the geometric 3-D method, we picked any three non-collinear CDP points along two orthogonal CDP survey lines to calculate two apparent dips. Thus the true dip and strike corresponds to these three points can be settled. The contouring of 3-D model then was obtained by statistical estimation using kriging with variogram.