KENNICUTT, MAHLON C., II, ADOLPHO G. REQUEJO, ROGER SASSEN, and JAMES M. BROOKS, Geochemical and Environmental Research Group, Texas A&M University, College Station, TX

ABSTRACT: Oil Formation in the Northern Gulf of Mexico: Geochemical Evidence

The occurrence of petroleum in the northern Gulf of Mexico is initially controlled by the quality, quantity and areal extent of source rocks. Source rocks spanning a wide range of ages have been documented at one or more locations within the basin. Prolific sources of Upper Jurassic, Lower Cretaceous, Upper Cretaceous, and Paleogene age have been recognized. The Paleogene is a primary source of coastal and continental shelf oils and the Mesozoic is an important source in the onshore and the deep water northern Gulf of Mexico. The thermal history of each of these source strata are related to depositional history. The amount and duration of deposition over geologic time determined when and where petroleum was generated as well as destroyed. Migration conduits in many locations are a dir ct result of salt tectonics. On the outer continental shelf these conduits act to fill Paleogene reservoirs and transport oil out of regions of thermal destruction. Extensive vertical migration throughout the basin is evidenced by displaced fluids, commingled fluids, and seabottom seepage of oil and gas. Mathematical models have been developed to recognize related oils, deconvolute complex histories, and infer the depositional environment and age of the source strata. A comprehensive model of petroleum formation inthe northern Gulf of Mexico will be presented and implications for deep water exploration will be discussed.

AAPG Search and Discovery Article #90987©1993 AAPG Annual Convention, New Orleans, Louisiana, April 25-28, 1993.