By: R. F. Biek
The Kolob Arch quadrangle is at the western margin of the Colorado Plateau, in the transition zone between the Colorado Plateau and Basin and Range physiographic provinces. The Colorado Plateau province is a relatively coherent and tectonically stable region underlain by generally horizontal sedimentary strata that are locally disrupted by early Tertiary Laramide basement-block uplifts, Oligocene/Miocene igneous intrusions, and late Tertiary to Quaternary basaltic lava flows. The Basin and Range Province is characterized by thinned crust and roughly eastwest extensional tectonics, with block faulting and widespread igneous activity. The Hurricane fault, which bisects the quadrangle, is the easternmost major fault of the Basin and Range Province in southern Utah. The transition zone is characterized by sedimentary strata and structures common to both physiographic provinces. In southwest Utah, the transition zone also roughly corresponds to the leading edge of the Late Cretaceous to early Tertiary Sevier orogenic belt, which is expressed as the fault-propagation folds of the Kanarra and Virgin anticlines.
This geologic map has three plates, a geologic map at 1:24,000, an explanation sheet, and notes on the geology of the quadrangle.
Plates: 3 pl.
Location: Iron County and Washington County
Media Type: Paper Map