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Independent Petroleum Geologist and Consultant, 1777 Larimer Street, Denver, CO 80202, USA
The US portion of the Gulf Coast Basin is that country’s greatest petroleum province, having produced about 31% of the oil and about 48% of the gas. Jurassic evaporites, deposited in basins opened by Mesozoic drift, underlie much of an area which received marine, mainly clastic, upper Mesozoic and Cenozoic deposits. Three small tensional basins were filled by late Eocene time. A large paralic basin remains an area of active deposition. Petroleum is produced from Mesozoic carbonates and clastics in the tensional basins, often from salt-related features, and from Cenozoic clastics in the paralic basin, where salt domes are common. Eocene fault-trapped production dominates in salt-free south Texas. Oligocene production, often from diapiric structures, is most important in coastal Texas and southwestern Louisiana. Miocene and younger production, usually salt-related, dominates in onshore and offshore south Louisiana. Favourable factors include large volume deposition and rapid burial, early and continuing structural development, lack of sand cementation and excellent source characteristics.
