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C. W. Keighin

Publications and source records attributed to C. W. Keighin.

14 recordsLinked to original sources
USGS1999

National coal resource assessment non-proprietary data: Location, stratigraphy, and coal quality for selected tertiary coal in the Northern Rocky Mountains and Great Plains region

One of the objectives of the National Coal Resource Assessment in the Northern Rocky Mountains and Great Plains region was to compile stratigraphic and coal quality-trace-element data on selected and potentially minable coal beds and zones of the Fort Union Formation (Paleocene) and equivalent formations. In order to implement this objective, drill-hole information was compiled from hard-copy and digital files of the: (1) U.S. Bureau of Land Management (BLM) offices in Casper, Rawlins, and Rock Springs, Wyoming, and in Billings, Montana, (2) State geological surveys of Montana, North Dakota, and Wyoming, (3) Wyoming Department of Environmental Quality in Cheyenne, (4) U.S. Office of Surface Mining in Denver, Colorado, (5) U.S. Geological Survey, National Coal Resource Data System (NCRDS) in Reston, Virginia, (6) U.S. Geological Survey coal publications, (7) university theses, and (8) mining companies.

Open-File Report↗
USGS1993

The Point Lookout Sandstone: a tale of two cores, or petrology, diagenesis, and reservoir properties of Point Lookout Sandstone, Southern Ute Indian Reservation, San Juan Basin, Colorado

The Point Lookout sandstones are quartz-rich, fine to very-fine grained, and contain moderately variable quantities of potassium feldspar (2 to 20 modal percent) and lithic fragments (9 to 20 modal percent). Locally, sandstone is tightly cemented by carbonate cement; clays are not important as cementing agents, although they significantly reduce permeability of some samples. Pores are small; many are intergranular micropores between crystals of authigenic clay. Depositional environments are highly variable and range from lower shoreface to coastal plain and include minor deltaic environments. The best reservoir characteristics are generally in the upper shoreface sandstones. -from Authors

Mountain Geologist↗
USGS1993

Reser­voir anisotropy and facies stratigraphic framework in the Pale­ocene Fort Union Formation, western Wind River basin

Investigation of reservoir anisotropy and lithofacies stratigraphic framework in the Fort Union Formation in western Wind River Basin, Wyoming focused on excellent surface exposures in the Shotgun Butte, Eagle Point, and Shotgun Bench synclines, and in the Merriam anticline area of the Wind River Reservation ( Fig. 1 ). A complementary study was made of the formation in the Muddy Ridge and Pavillion gas fields, 8-10 mi to the southeast ( Fig. 2 ). The Fort Union Formation is as much as 4000 ft thick in these areas, but thins to approximately 1800 ft toward the northern flank of the Little Dome anticline 3 mi south of Merriam anticline ( Keefer and Troyer, 1964 ). The Fort Union Formation includes interbedded conglomerates, sandstones, siltstones, mudstones, coals, and carbonaceous shales ( Fig. 3 ). The lower member of the Fort Union Formation is dominated by conglomerates and sandstones. The overlying Shotgun Member of the Fort Union Formation mainly consists of siltstones, mudstones, and carbonaceous shales, and coals, and subordinate sandstones. Contact between the lower member and Shotgun Member is gradational and marked by a topographic change from the resistant conglomerates and sandstones of the lower member to less resistant fine-grained strata of the Shotgun Member. In addition, the Shotgun Member commonly contains coal and carbonaceous shale beds, both in the surface and subsurface ( Fig. 4 ). About 15-20 mi east of the study area the Waltman Shale Member of the Fort Union Formation pinches out at the contact between the lower member and Shotgun Member (Keefer and Johnson, this volume). The Waltman Shale Member, which consists of brown to gray silty and shaly claystones interbedded with sandstones, increases in thickness to as much as 3000 ft eastward into the basin center (Keefer, 1961 ; 1965 ). Thus, eastward, the Paleocene Fort Union Formation in ascending order, contains the lower member, Waltman Shale Member, and Shotgun Member. The Shotgun Member generally thins and interfingers with the Waltman Member.

Conference Paper↗
USGS1982

Characteristics and description of cores from the USGS core hole CRU-1, Parachute Creek Member, Green River Formation, east-central Uinta Basin, Utah

Oil-yield, lithologic, and mineral distribution data were determined for cores taken from a 497.7-foot drill hole in the upper part of the Parachute Creek Member of the Eocene Green River Formation. The drill hole, 1050 feet FEL, 700 feet FNL, sec. 3, T. 12 S., R. 24 E., Uintah County, Utah, started slightly below the contact between the Uinta Formation, also of Eocene age, and the underlying Green River Formation. It ended 32 feet below the base of the Mahogany bed (the richest oil-shale bed between A groove and B groove--which define the upper and lower boundaries, respectively, of the Mahogany zone). Most of the interval studied is kerogen- or carbonate-rich, commonly tuffaceous, and is very fine grained. Several thin (<3 feet) oil-shale beds which yield as much as 25 gallons of oil per ton occur above the Mahogany zone, but are probably not of economic interest. The cored sequence contains several tuff beds. The thickest of these beds is approximately 2 feet thick; the average thickness is rarely greater than 0.5 feet. Two oil-saturated tuff beds occur approximately 65 feet above the Mahogany oil-shale bed. Although these two tuffs are exposed on nearby surface outcrops, no evidence of oil is seen on outcrop. The Mahogany zone is approximately 69 feet thick at the drill site; the lowermost few feet were not penetrated. At the site cored, the Mahogany zone is overlain by 435 feet of overburden. Fischer assays indicate that 42.3 feet of oil shale within the Mahogany zone could yield at least 25 gallons of oil per ton from beds at least 10 feet thick.

Open-File Report↗