The Gulf of Mexico can be divided into two major provinces: a carbonate province on the east and a terrigenous one on the west. The steep side slopes of the Campeche (Yucatan) and Florida (U.S.A.) escarpments are not fault scarps, but were formed during the Cretaceous by carbonate deposition along the seaward edge of the subsiding continental block. After the algal banks or reefs that formed the steep side slopes died, sediment progradation and upbuilding formed the shelf and the smooth and gentle upper continental slope. Seaward progradation extended to the top of the escarpments and buried the algal banks.

The continental margin within the terrigenous province between De Soto Canyon and Campeche Canyon was formed by upbuilding and outbuilding. The resulting sedimentary framework has been altered by salt intrusions. The Sigsbee escarpment at the seaward edge of the sedimentary framework was also formed by salt intrusion. Diapiric structures are not limited to the continental margin, but extend into the center of the Gulf of Mexico basin. Structures in the center of the basin appear to be restricted to the eastern margin of the Sigsbee abyssal plain and are aligned in a northeasterly direction. This trend and concentration, if real, may delineate a fracture zone extending from De Soto Canyon to the Golfo de Campeche.

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