Subsequent burial by 40,000 ft. of continental margin sediments has induced hydrostatic loading and compaction of the salt and overlying sediments. Plastic deformation of the low-density salt has caused diapiric intrusion into the overlying sediments. Exxon conducted a seismic study of the Block 54 area. Structural mapping and interpretation were aided by plotting directly on the seismogram. The array of normal and thrust faults was mapped first.
Many faults extend from the surface to the top of the dome.
These faults are accompanied by shorter antithetic faults, which either stop at the main fault or die out towards the surface. Smaller faults parallel the larger main faults but do not extend as deep into the section. An erosional disconformity was found near the top of the section. As observed in the seismograms, regular horizontal beds are abruptly terminated by an erosional surface and then overlain by undifferentiated sediments. The erosional surface spans the entire study area and deeper areas define a channel.