Origin and Development of Northern Green River Basin: A Stratigraphic and Flexural Study: ABSTRACT

Abstract

Two-dimensional profiling of the northern Green River basin using topographic, stratigraphic, and structural information shows that the basin can be modeled effectively as a flexural depression resulting from extrabasinal and intrabasinal loading on an elastically behaving lithosphere. Two distinct approaches were used: present basin geometry profiling and sediment thickness profiling. Present basin geometry profiling involves analysis of predicted present-day basin configuration compared with the observed configuration. Sediment thickness profiling, a procedure based on isostatic compensation for flexural responses to loading, relates stratigraphic thickness of basinal rocks to coeval tectonic loading. Results of both methods suggest the lower Tertiary and perhaps some u permost Cretaceous sediments accumulated as a result of flexure due to loading by the Darby and Prospect thrusts to the west and the Wind River foreland thrust to the east. Moreover, results of the sediment thickness profiling are of predictive value resolving stratigraphic problems and timing structural events. Tentative results imply that (1) the northern Green River basin was essentially full by the end of the early Eocene and subsequent erosion has been negligible, and (2) the first movement on the Wind River thrust in the latest Cretaceous was significant in controlling basin configuration. End_of_Article - Last_Page 527------------