In addition to a detailed geologic map of the Trapper Canyon Tar Sand Deposit, this report provides descriptions of the tar zone and the adjacent barren zones. Samples collected in the field were analyzed for porosity, permeability, oil saturation, and characteristics of the oil. Thin sections of material from both the tar zone and barren zones were examined to determine textural characteristics and kinds of pore-filling cements. Samples were examined using the scanning electron microscope to gain insight into the diagenesis of the reservoir rock and the trapping mechanism.