Tectonic Significance of Currant Creek Formation, North-Central Utah: ABSTRACT

The Currant Creek Formation is composed of conglomerate, sandstone, and fine-grained clastic rocks that crop out along the northwestern margin of the Uinta basin in north-central Utah. Lateral gradations in grain size define proximal, medial, and distal parts of coalescing alluvial-fan deposits that prograded eastward from the active Sevier-Laramide orogenic belt during Maestrichtian through Paleocene(?) time. Paleocurrent directions indicate a dominant southerly transport direction and a minor easterly component. Strong east and southeasterly directions, measured in imbricated clasts and in sand lenses in conglomerate, indicate multiple source areas for the detritus. Source of the coarse-grained detritus in the Currant Creek Formation was the Charleston thrust sheet. Conglomeratic clasts are composed of Precambrian and Cambrian quartzite, chert derived from Cambrian and Mississippian carbonate beds, and Pennsylvanian sandstone. These rocks are exposed in the upper plate of the Charleston thrust near Deer Creek Reservoir, Mount Timpanogos, and Strawberry Reservoir. At Big and Little Canyons, the same rocks are exposed in the lower plate. A large basement-cored east-verging anticline that is refolded around the Uinta Mountain structure is present in the region. By the time of its final emplacement, the Cottonwood fold likely formed a small mountain range. Erosional dissection was well under way and Carboniferous, Cambrian, and Precambrian beds were exposed. The Charleston-Absaroka thrust rises in the stratigraphic section farther east, displacing Mesozoic rocks. Reworking of Cretaceous sandstone and shale flanking the newly uplifted western end of the Uinta arch also contributed sediment to southward-flowing streams. End_of_Article - Last_Page 939------------