BARTOK, PEDRO, EGEP Consultores, Caracas, Venezuela

ABSTRACT: Pre-breakup Geology of the Gulf of Mexico-Caribbean: Its Relation to Triassic and Jurassic Rift Systems of the Region

A review of the pre-breakup geology of west-central Pangea, comprised of northern South America, Gulf of Mexico and West Africa, combined with a study of the Mesozoic rift trends of the region confirms a relation between the rift systems and the underlying older grain of deformation. The pre-breakup analysis focuses attention on the Precambrian, Early Paleozoic and Late Paleozoic tectonic events affecting the region and assumes a Pindell fit. Two Late Precambrian orogenic belts are observed in the west central Pangea. Along the northern South American margin and Yucatan a paleo northeast trending Pan-African aged fold belt is documented. A second system is observed along West Africa extending from the High Atlas to the Mauritanides and Rockelides. During the Late Paleozoic, renewed or genic activity, associated with the Gondwana/Laurentia suture, affected large segments of west central Pangea. The general trend of the system is northeast-southwest and essentially parallels the Guayana Shield, West African, and eastern North American cratons. Mesozoic rifting closely followed either the Precambrian trends or the Late Paleozoic orogenic belt. The Triassic component focused along the western portions of the

Gulf of Mexico continuing into eastern Mexico and western South America. The Jurassic rift trend followed along the separation between Yucatan and northern South America. At Lake Maracaibo the Jurassic rift system eventually overlaps the Triassic rifts. The Jurassic rift resulted in the "Hispanic Corridor" that permitted Tethyan and Pacific marine faunas to mix at a time when the Gulf of Mexico underwent continental sedimentation.

AAPG Search and Discovery Article #90988©1993 AAPG/SVG International Congress and Exhibition, Caracas, Venezuela, March 14-17, 1993.