This report presents the geophysical logs for 13 drill holes drilled during 1979 in the Convulsion Canyon-Duncan Mountain area, Acord Lakes quadrangle, Sevier County, Utah. The drilling was done by the Utah Geological and Mineralogical Survey under contract to the U.S. Geological Survey. The sites of all of the drill holes are within the Wasatch Plateau Known Recoverable Coal Resource Area (KRCRA) and in the Richfield Ranger district of the Fishlake National Forest. The purpose of the drilling was to identify and evaluate coal resources under public lands that may be included in a future coal leasing program.
The area is underlain by Cretaceous and younger rocks (table 1). The coal seams of economic interest are in the lower 200 ft of the Upper Cretaceous Blackhawk Formation, a complex sequence of intertonguing sandstone, shale and coal. Regional dip of the strata in the area is approximately 2° to the northwest. The geology and coal resources of the area were described by Spieker (1931) and Doelling (1972).
Most of the drill holes were rotary drilled and the thicknesses and depths were determined from geophysical logs. In order to obtain data on the quality of the coal, the coal-bearing section in selected holes was core drilled. Table 2 gives the drilling and logging information for the 13 completed holes. All drill holes were bottomed in the Upper Cretaceous Star Point Sandstone.
