Abstract

This study consists of a series of maps that depict in a very general way, an interpretation of the geography, dominant depositional environments, tectonic, and erosional activities in a sequence ranging in time from Mid-Proterozoic to the end of Cretaceous. It does not cover Laramide tectonics and subsequent Cenozoic activity. The area covered includes Oklahoma, New Mexico, and north, central and west Texas. Selected formation or group names are shown on many of the maps as being typical of that particular time period. Isopach values and contours are shown in a number of areas where structural subsidences have received significant thicknesses of sediments. It is a story of repeated episodes of transpression giving rise to strike-slip faulting and the formation of lateral uplifts, and of basins that became filled with erosional clastics from those uplifts, that were deposited almost exclusively in prograding (regressive) semi-cycles. The story also tells of the upwellings and sinkings of the thermal cells in the asthenosphere, and their considerable effect on the crust and its sedimentary veneer. The most intense structural activity in the area is associated with the Oklahoma megashear (OM) and the Texas megashear (TM). In tectonically quiet areas, carbonates and evaporites were deposited. During these events, the water depths on the epi-continental seas were fairly shallow, with most sedimentation keeping pace with subsidences.