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The Hoback Basin of western Wyoming is in the zone of impingement between ranges of the Idaho-Wyoming thrust belt on the west and the Gros Ventre and Wind River foreland uplifts on the east. These ranges shed synorogenic clastic debris that filled the basin during Late Cretaceous and Tertiary time. Structural, stratigraphic, and sediment provenance studies provide detailed information on the chronologic and geometric relation between these two structural styles.

Eastward thrusting in the thick sequence of miogeosynclinal rocks to the west began somewhat earlier than did reverse faulting, which uplifted blocks in the adjacent foreland. Subsequently, however, both areas underwent contemporaneous deformation, so that thrust belt and foreland structures overlap geographically and temporally. Furthermore, the last datable movements are the same age for both thrusts and major reverse faults. The Late Cretaceous rise of the ancestral Teton–Gros Ventre uplift and the subsequent rise of the Gros Ventre block provided a high-standing buttress of Precambrian rocks that deflected structures in the eastern part of the thrust belt. Late normal faulting and associated gravity sliding, possibly along a pre-existing, thrust-weakened zone, occurred in the thrust belt, and the Hoback and Gros Ventre Ranges acted as an integral block in spite of their previously distinct structural histories. Normal faulting also occurred in the foreland uplifts and, in some places, brought Precambrian rocks to the surface. Local tectonism and associated basin fill ceased by late Pliocene time in the Hoback Basin, and regional uplift initiated the dissection of both the lower Tertiary sediments and pediments of parts of adjacent ranges.

Although the intimate spatial and temporal relations of the thrust belt and foreland structural styles do not require a single casual mechanism, they do suggest that thrusting in the thrust belt and uplift in the adjacent foreland were not entirely genetically separate.

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