Early Cenozoic reverse drag along the Hurricane fault zone of Utah and Arizona resulted in deposition, in the drag zone, of an abnormally thick accumulation of the Paleocene to Eocene Claron Formation. Much of the original sediment has been preserved. Stratigraphic separation of pre-late Oligocene age along the Hurricane fault amounted to more than 8,000 ft (2,440 m), or 85 percent of the total stratigraphic displacement. This separation is apparent from the juxtaposition of the late Oligocene to early Miocene Pine Valley laccolith of the western block with the Kaibab Limestone of the eastern block. These two independent facts—local thick deposition of the Paleocene to Eocene(?) Claron Formation, and the mode and time of emplacement of the laccolith—suggest major Laramide to Eocene movement on the Hurricane fault. Because Colorado Plateau uplift, with respect to the Basin-Range region, occurred as the result of Hurricane fault displacement, the conclusion is that major differential uplift of the Colorado Plateau occurred early in the Cenozoic.

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