Tar sandstone investigation in southwestern Uinta Basin

During the month of July 1972, the author assisted by Jonathan Mann studied the oil impregnated sandstone (hereafter OISS) deposits in the Lower Unit of the Parachute Creek Member of the Green River Formation on the southwestern edge of the Uinta Basin, along the Roan Cliffs and within the Roan Plateau. Careful mapping was conducted to determine the extent of the Sunnyside OISS deposit and to relate it to other deposits in the general vicinity. In addition to this mapping, which was restricted to the Flat Canyon and Sunnyside 15 min. quadrangles, (correlation investigations? ) were carried out in Nine Mile Canyon, Argyle Canyon, Indian Canyon, and at the headwaters of Avintaquin Canyon near Reservation Ridge (see USGS 7 1/2 min. quadrangles Gray Head Peak, 1969, and Flat Ridge, Utah, 1969). These areas, in this report, are further subdivided into smaller regions (often ridges or canyons) for further expansion of the results of the investigation. A number of the canyons could only be studied by hiking them through, others because of the size of the area studied and time requirements were studied by numerous stops from a four-wheel-drive truck. A field method to categorize the estimated richness of the OISS was used in the mapping: A numeral from I-V was assigned to a deposit, I being void of tar and progressing with each number until very rich OISS would be classed as V.