Published:January 01, 1991
Throughout most of Early Cretaceous time, the Gulf of Mexico basin was a major site of continental and marine deposition surrounded by the Appalachian and Ouachita uplands on the north, the Llano and Marathon uplifts on the northwest and the Chiapas massif and Maya Mountains to the south. During this time there were marine connections to the Pacific Ocean to the west and to the Atlantic Ocean to the southeast. The Gulf of Mexico basin was tectonically stable except for continuing slow subsidence of its central part, growth faulting on the margins of some depocenters, and local deformation related to underlying Jurassic salt. Shallow-marine water covered its rims and peripheral shelves, and progressively deeper waters its slope and abyssal plain.
Lower Cretaceous rocks form a continuous disc of sediments, which thin and pinch out updip along the periphery of the Gulf of Mexico basin. Lower Cretaceous sequences crop out along the northwestern, western, southwestern rims of the basin. No Lower Cretaceous outcrops are known east of the Mississippi River nor in the Florida and Yucatán Peninsulas (Fig. 1).
The Lower Cretaceous sediments are primarily carbonates and evaporites on the circum-Gulf shelves, and carbonates in the bathyal areas. Continental and shallow-marine terrigenous clastic sediments occur primarily around the northern and northwestern rims of the basin, from northeastern Mexico to the Florida panhandle. They are most prevalent in the lower part of the Lower Cretaceous section (Berriasian to Barremian), and represent the sediment load of rivers draining the continental interior and the
Figures & Tables
The Gulf of Mexico Basin
Eighteen chapters deal with the entire Gulf of Mexico basin. Included are significant contributions from Mexican geologists. Nine topical chapters cover regional aspects of physiography and bathymetry, structural framework, the basement crust, salt tectonics and listric faulting, igneous activity, seismic stratigraphy, oil and gas resources, mineral resources and geopressured-geothermal energy, and ground water. Six chapters summarize regional stratigraphy and paleogeography for the pre-Triassic, Triassic-Jurassic, Lower Cretaceous, Upper Cretaceous, Cenozoic, and late Quaternary. Also included is a synthesis of the origin and development of the Gulf of Mexico basin. Six 4-color plates summarize the bathymetry, natural resources, tectonics, and basement structure and subcrop of the region, and provide a stratigraphic correlation chart and geologic cross sections.