ABSTRACT

Two magnetic models of the West Florida Escarpment have been constructed. These models represent a synthesis of seismic reflection data recorded on the continental slope of western Florida by Texas A&M University, information from numerous oil companies, and early refraction results from the Gulf of Mexico Basin. Theoretical magnetic anomalies computed from these models are consistent with previously published magnetic data for the slope, scarp, and basin.

These models show that the presence of a fault with a throw of 10,000 feet in the basement under the Florida escarpment can be reconciled with the essentially smooth magnetic field shown in previously published charts. These magnetic data had earlier been interpreted to indicate that no basement fault could be associated with the escarpment. In the models presented here, subsidence of both the platform and basin is considered; the assumption being made that the basin has subsided more rapidly.

On the basis of these data and the magnetic models, a geologic cross section is presented which includes basement faulting, reef buildup and volcanics, the latter, although probably present, are not related to the origin of the scarp. This geologic model consists of a continental platform with an upper section of limestone, dolomites, and anhydrites laid down in a shallow water environment. The outer edge of the slope is bordered by buried reefs and the dip of the scarp face is shown to decrease with depth under the abyssal plain sediments. The basin is depicted as a modified oceanic region. A transition from oceanic to continental crust is assumed with a fault or flexure, indicating differential movement of the platform and basin, present near the base of the scarp.