New data from a small enclave that did not undergo significant Neogene tectonism in northwest Utah document Eocene tilting, normal faulting, land folding of the early Eocene lacustrine White Sage Formation. This deformation was part of a complexly deformed Eocene Sevier-Laramide hinterland that underwent east-west contraction and extension in different areas and ultimately gave way to widespread Oligocene extension in the eastern Great Basin. Such “mixed-mode” supracrustal Eocene tectonism may reflect local adjustments to maintain a state of regional gravitational equilibrium, or may record responses to changing plate convergence rates at the west edge of the continent.

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