Lower Cretaceous extrusive and intrusive igneous rocks. Antillean and Caribbean orogenic events. Folds are noncompressive and the result of growth faulting, syndepositional subsidence of grabens filled with Tertiary sediments. Sedimentary rocks in western Jamaica are shallow-water and deltaic sequences. Exploratory drilling has been concentrated on recognized surface and subsurface anticlinal traps. Various requirements for accumulation of the commercial hydrocarbons are not present in any of those structures. In contrast, stratigraphic traps exist in Jamaica and are probably very abundant.--Modified journal abstract.