Description |
The Currant Creek Formation of Late Cretaceous to Early Eocene age is located on the northwestern flank of the Uinta Basin and on the southwestern flank of the Uinta Mountains. The Currant Creek unconformably overlies the Mesaverde Formation of Late Cretaceous age and unconformably underlies the Uinta (?) Formation of Early Eocene age. The age and correlation of the Currant Creek is based on previous work by Walton (1944 and 1964), Abott (1957), and Murany (1963 and 1964); field evidence, and subsurface information. Field evidence for correlation consists of unconformities, basal conglomerates, stratigraphic position, lithologic similarities to correlative formations, and conglomerate beds containing Upper Cretaceous fossils. Sub¬ surface information consists of electric and lithologic log correlations by the writer, and structural contour mapping. The Currant Creek Formation is tentatively correlated with the Bennion Creek, North Horn, Flagstaff, and Colton Formations of the Wasatch Plateau; the Wasatch Formation of the Uinta Basin; and the Knight and Echo Canyon Formations of the Wasatch Plateau. The Currant Creek Formation is a series of interbedded conglomerate, sandstone, siltstone, and shale. The lower part of the formation is predominantly sandstone and conglomerate and the upper part is mainly sandstone, siltstone, and shale. Individual rock units are composed of lithic (petromict) boulder, cobble, pebble, and granule conglomerates, orthoquartzite to subgraywacke sandstones, siltstones, and sandy-silty-calcareous shales. The formation ranges from about 4,800 feet thick in the Currant Creek area to about 4,000 feet thick in the Red Creek area, and in the Duchesne River-Little Valley areas it thins to 1,500 feet thick. The formation pinches out eastward from Little Valley. Three erosional pediment surfaces are developed in the area and are correlated, from oldest to youngest, with decreasing elevation, to the Lake Mountain, Jensen, and Vernal or Thornburg surfaces described in the Vernal, Utah area by Kinney (1955). The term Uinta Basin Fault is proposed for a subsurface fault that trends northeast-southwest and roughly follows the trace of the Uinta Basin axis. The fault is believed to be a thrust fault. Bituminous sandstone deposits are present in the Duchesne River-Little Valley area in the Uinta (?) and Currant Creek Formations and offer some potential for future economic development. |