Characteristics of the PR Spring Tar Sand deposit, Uinta Basin, Utah, U.S.A.

The Laramie Energy Technology Center (LETC) conducted a seven-corehole drilling program in the PR Spring tar sand deposit, southeastern Uinta Basin, Utah, during the summer of 1980. Three main tar sand zones in the southwestern and west-central portion of the deposit were correlated by cross sections, using six of the seven LETC coreholes. The saturated beds and zones are lenticular and discontinuous over both large and small areas. As determined by the LETC cores and twenty eight previously drilled cores in the deposit, from one to twenty seven separate tar sand beds at least one foot thick of continuous saturation exist in the deposit, the thickest of which is 10.7 m (35 ft) thick. Analytical results from the LETC cores and the twenty eight other cores were integrated to further evaluate tar sand characteristics of the deposit. The following general trends were noted: extracted permeability and extracted porosity decrease downdip (northwest); oil saturation decreases to the west-southwest; and water saturation decreases to the east.