A Tale of Two Superbasins: Comparing Basin Geometry and Petroleum Systems in the Northern Gulf of Mexico and the West Texas (Permian) Basins

Abstract

Texas contains large parts of two of the worlds ‘super basins’, the Northern Gulf of Mexico Basin and the Permian Basin. Comparison of the hydrocarbon systems and geometries of these complex postrift subsidence basins of the Gulf Coast / Gulf of Mexico yield useful insights for basin evolution and play development. The West Texas basin, a complex intracratonic basin of Paleozoic age, contains source rocks in the Ordovician and Devonian, but much generation comes from Late Mississippian, Pennsylvanian and Permian basinal sediments. These were deposited in a poorly ventilated remnant basin during compression and strike-slip of the Ancestral Rocky Mountains orogeny, and subsidence of the intracratonic Permian Basin. Maturation resulted from Permian intracratonic subsidence, with hydrocarbons sealed from later leakage by late Permian salt and a fortunate tectonic setting. By contrast, in the Northern Gulf of Mexico Basin, a complex passive margin basin with major salt-related structuring, the major Jurassic source rocks of the Gulf basins are at the base of the postrift subsidence, and are matured by further subsidence. Later Cretaceous source rocks (Eagle Ford) are mature in the main Gulf basin, but again lie near the bottom of the thick Cenozoic sedimentary package in the area. The younger Cenozoic shelf-margin succession yields mostly gas formed during outbuilding of the shelf margin by Cenozoic deltaic progradation. No cap is present on the basin (except for subsalt plays), and seepage is widespread.

From these two basins the following criteria for a superbasin are proposed: Prolific production and/or reserves identified; Multiple source rock intervals at different levels of the basin; complex structuring yielding diverse, migration pathways, traps and play concepts; and regional high-quality seals.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018