Abstract

Following the deposition of the Late Paleozoic Kaibab Formation, three periods of structural deformation are recognized in southwestern Utah. The earliest structural event is the uplift of western Utah during the Late Permian and Early Triassic that resulted in erosion cutting channels in the Kaibab Formation and facies changes in the Lower Triassic that were favorable to the development of oil traps in the Timpoweap Member of the Moenkopi Formation. The second major tectonic episode attributed to the Laramide and Sevier Orogenies, is the continuous development of thrusting and folding that resulted in the formation of the major thrust and fold belt in southwestern Utah. Block faulting was the last structural deformation to occur in southwestern Utah during the Late Tertiary and Early Quaternary Epochs. This faulting was affected by the location of the earlier thrust faults and folds. Block faulting produced slopes that had sufficient gradient to allow gravity slide and rotational structures to develop.