| Description |
Tar-sand, or oil-impregnated sandstone, deposits and occurrences of the Uinta Basin, Utah are summarized and presented. Twenty five tar-sand deposits/occurrences are reviewed with respect to geology, locations of bitumen saturated outcrops, land ownership, physiography, bitumen-analyses, development histories, and other aspects. Background information on the physical setting and regional geology of the Uinta Basin is presented along with discussions of theories on the sources of the bitumen. Four areas-Asphalt Ridge, P.R. Spring, Hill Creek, and Sunnyside are presented as the principal areas containing most of the tar-sand resource. The Asphalt Ridge tar-sand deposit, located on the north flank of the Uinta Basin and enclosed in steeply dipping rocks of the Mesaverde Group (Cretaceous) and Duchesne River Formation (Eocene-Oligocene), is estimated to contain more than 1 billion barrels of oil. The P.R. Spring and Hill Creek deposits, located along the southeast margin of the basin and enclosed by gently dipping rocks of the Green River Formation (Eocene), are estimated to comprise a resource in excess of 4 billion barrels of oil. The Sunnyside deposit, located along the south margin of the basin enclosed by rocks of the Wasatch and Green River Formations (Eocene) is the largest of the deposits, estimated to contain more than 5 billion barrels of oil. The remaining 21 areas discussed are scattered along the northern and southwestern margins of the basin. Along the northeastern side of the basin lies the Raven Ridge, Cow Wash, Rimrock, Spring Hollow, and Upper Kane Hollow deposits. The Chapita Wells and Pariette deposits, located in the central part of the basin are contained in rocks of the Uinta Formation (Eocene), but may be related to near-vertical faults and fractures. Deposits along the southwestern side of the Uinta Basin that may be genetically related to the Sunnyside deposit include Argyle Canyon, Minnie Maud Creek, Ninemile Canyon, and Willow Creek. The Whiterocks deposit, along the north basin margin is unique because it occurs in the Navajo Sandstone of Jurassic age. The Daniels Canyon deposit, located just outside of the western margin of the basin, is associated with fractures in Paleozoic rocks. The Thistle and Oil Hollow deposits, located at the extreme western end of the basin, are contained in oolitic limestone of the Paleocene Flagstaff Limestone and the Green River Formation, respectively. |
