Seismic stratigraphic techniques permit identification of Upper Triassic, Jurassic, and Lower Cretaceous sequences in strata from the North American Gulf Coast and West Africa. Several distinct sequences are remarkably persistent from the Florida panhandle, around the perimeter of the Gulf Coast and into northern Mexico, a distance of more than 1,500 mi (2,400 km). Their identification requires the integration of seismic data with lithologic, environmental-facies, biostratigraphic, radiometric, and well-log information. A comparison with strata of comparable age offshore West Africa indicates the same sequences can be recognized there. The sequences in North America and Africa are interpreted to be controlled by global changes of sea level because they occupy the same tim -stratigraphic positions and display coastal onlap patterns similar to those previously recognized elsewhere.

Gulf Coast seismic sequences and the formations present within them are: (1) Upper Triassic and Lower Jurassic (Hettangian?)--Eagle Mills Formation; (2) Lower Jurassic (Sinemurian through Toarcian)--known only from southern Mexico and not identified in the study area; (3) Middle Jurassic (Bajocian-Bathonian)--Werner anhydrite-Louann Salt interval; (4) upper Middle Jurassic (Callovian)--Norphlet Formation; (5) Upper Jurassic (Oxfordian-Kimmeridgian)--Smackover-Buckner-Gilmer (Haynesville) Formations; (6) Upper Jurassic-Lower Cretaceous (Tithonian-Berriasian)--most of the Cotton Valley Group; and (7) Lower Cretaceous (Valanginian)--a restricted sedimentary wedge seen only in a basinward position.

West African seismic sequences are: (1) Upper Triassic and Lower Jurassic (Hettangian?); (2) Lower Jurassic (Sinemurian through Toarcian); (3) Middle Jurassic (Bajocian); (4) Middle Jurassic (Bathonian); (5) Middle Jurassic (Callovian); (6) Upper Jurassic (Oxfordian-Kimmeridgian); (7) Upper Jurassic-Lower Cretaceous (Tithonian-Berriasian); and (8) Lower Cretaceous (Valanginian).