Abstract: Shallow Seismic Survey on Weeks Island, Louisiana: An Attempt to Define "Top of Salt"
Gary L. Kinsland, Paul Schank, Bill Rutter, III
We have collected, processed, and interpreted about 10,000 ft (3300 m) of 2-D high-resolution (CDP interval 2.5 ft [.75 m], 12 fold, 100 hertz dominant frequency), shallow (about 250 ft [75 m] depth) seismic data in an area about 2200 ft (700 m) by 500 ft (125 m) on Weeks Island, Louisiana. The objective was to image the salt-clastic sediment interface--"top of salt." Both surface sources and buried explosive sources have been used. The data have been processed for both reflection and refraction information.
Interpretation of the results has led to the following conclusions: (1) "top of salt" is not a sharp seismic interface at these frequencies, (2) there are sharp seismic interfaces within the clastic section, and (3) these sharp clastic interfaces are laterally discontinuous. These conclusions support these hypotheses: (1) the "top of salt" is a heterogeneous solution zone grading from clastics to salt over many feet, with water-filled voids common, (2) similar voids have led to collapse as salt has dissolved, and (3) these collapses are manifested in the discontinuous clastic reflectors and in the topography of the surface.
AAPG Search and Discovery Article #90983©1994 GCAGS and Gulf Coast SEPM 44th Annual Meeting, Austin, Texas, October 6-7, 1994