Abstract: Post Mid-Cretaceous Depositional History, Gulf of Mexico

Jianhua Feng, Richard T. Buffler

A detailed seismic stratigraphic analysis of the deep Gulf of Mexico basin has resulted in the definition of eighteen post mid-Cretaceous seismic sequences. The establishment of a preliminary chronostratigraphic framework allows for the first time construction of Gulf-wide isopach and depositional systems maps by integrating the results from the deep basin study with those from previous studies around the periphery of the deep basin.

The post mid-Cretaceous basin infill history is documented by seven basinwide isopach maps (Late Cretaceous, Paleocene, Eocene, Oligocene, Miocene, Pliocene, and Pleistocene). Seven corresponding depositional systems maps reveal that spatial and temporal variation of deep water submarine fan systems is a response to shifts of shelf margin depocenters. Important sediment fairways transversing the slope, therefore, can be inferred.

The rapid eastward and southeastward progradation of Late Cretaceous-Eocene depocenters suggest that deposition during this time is largely a response to principal tectonic events within the North America plate, particularly Laramide tectonic activity in Mexico. The continued basinward progradation of shelf margins during the late Cenozoic was accompanied by three major lateral shifts of depocenters, which may reflect changes within the Mississippi drainage system. These include (1) a major eastward shift during the Oligocene and Miocene, (2) a major southwestward migration during the Pliocene, and (3) a final eastward shift during the Pleistocene.

AAPG Search and Discovery Article #90950©1996 AAPG GCAGS 46th Annual Meeting, San Antonio, Texas