Paul Weimer¹, David R. Pyles², Seok-Hoon Yoon³

(1) University of Colorado, Boulder, Boulder, CO
(2) University of Colorado, Boulder, Boulder, CO
(3) Cheju National University, Cheju

ABSTRACT: Petroleum Potential of the Ultra-Deep Water DeSoto Canyon, Northeastern Gulf of Mexico

The ultra-deep northeastern Gulf of Mexico reflects one of the last frontier exploration areas in the U.S. Gulf. The area is tentatively to be leased in December 2001. Analysis of 10,000 km of 2-D seismic data allows us to evaluate the six components of petroleum systems of the area.

Potential reservoirs range in age from Upper Jurassic to Quaternary. Jurassic and Cretaceous strata are interpreted be primarily fine-grained, deep-water carbonate in origin. The Paleogene section is thin and condensed. Beginning during the middle Miocene, significant deep-water sediment was delivered to the area from the north (Mississippi Canyon area). These sediments reflect deposition in largely unconfined turbidite systems, so the need for large stratigraphic or combined traps is important for the development of this area.

Structural traps in the lease area consist of areally large, low relief closures associated with deformation of the Louann salt during the Cretaceous. Some of these structures include the Neogene sediments. Little to no allochthonous salt exists in the area. Adequate seals are interpreted to be present throughout the stratigraphic section because of the largely mud-dominated nature of the stratigraphic section.

Source rocks are interrupted to be present in the area. Carbonate-rich source rocks (Upper Jurassic) producing high sulfur oils are probably present. Oil seeps from the Mississippi Fan Foldbelt also indicate the presence of a mature Jurassic siliciclastic source interval. Petroleum systems modeling indicate that the deeper portions of the area is mature. The greatest risk is the presence of adequate traps and reservoirs to capture the large volumes of oil necessary for the province to be economic.

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