Vicente Ortega¹

(1) Pemex Exploracion y Produccion, Villahermosa, Tabasco, Mexico

ABSTRACT: Petroleum Systems in the Marine Coatzacoalcos Project, Southern Gulf of Mexico

The hydrocarbon habitat is related to the folded belts of Catemaco, Agua Dulce and Marbella, and those salt withdrawal basins in Pescadores and Comalcalco areas. Westward, there are a lot of exploratory opportunities consisting of folding affected by thrust faulting and the pinch outs of sands in their flanks. At central and eastern portions, salt domes influence is present and the opportunities are pinch outs of sand bodies in the flanks of the domes as well as in channels and barrier bars, all of them affected by normal faulting. The existence of hydrocarbons in the recognized plays above the salt indicates that there are potential reservoirs in subsalt plays, where the migration happens through faults, fractures and permeable zones. According to stratigraphic and geochemical studies, it is defined that the main source rocks are shally-mudstones and shales of Tithonian age. The plays above the salt domes, or on the irregular salt beds, range from Middle Miocene to Recent. The sandstones were deposited in floor fans, talus and the slope of the platform. The Cinco Presidentes Early Pliocene play is the most important in production rate. The exploratory risk is 1:2 to 1:5. The southern part of the Marine Coatzacoalcos Project has the best possibility to be developed in short term because it is close to the onshore giant oilfields and there are a lot of facilities to be transported, refined and exported.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado