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W. J. Mapel

Publications and source records attributed to W. J. Mapel.

31 records · Page 2Linked to original sources
USGS1963

Stratigraphic sections and correlation of beds in the Inyan Kara Group and Morrison Formation, north end of the Black Hills, Crook County, Wyoming, and Butte County, South Dakota

Descriptions of 47 stratigraphic sections of the Ivan Kara Group and Morrison Formation are given for an area extending from bluffs on the west side of the Belle Fourche River in T. 56 N., R. 64 W., Crook County, Wyo., southeastward across the Bear Lodge Mountains to a point in T. 8 N.,R. 1 E., Butte County, S. Dak.--a distance of about 35 miles. Also given are four sections measured farther southeast in the area between Belle Fourche and Rapid City, South Dakota. The Morrison, Lakota, and Fall River Formations are each subdivided into two parts and the subdivisions are correlated for most of the area.

South Dakota, Wyoming↗
USGS1959

Diagrammatic restored section of the Inyan Kara group, Morrison formation, and Unkpapa sandstone of the western side of the Black Hills, Wyoming and South Dakota

The Inyan Kara group of Early Cretaceous age and the underlying Morrison formation and Unkpapa sandstone of Late Jurassic age comprise about 300 to 850 feet of gently dipping predominantly nonmarine rocks that crop out along the flanks of the Black Hills in northeastern Wyoming and western South Dakota. Detailed mapping and stratigraphic studies of these rocks were made from 1952 to 1957 by the U.S. Geological Survey on behalf of the Division of Raw Materials of the U.S. Atomic Energy Commission. One of the results of the studies is a correlation of formational and intraformational units along the western side of the Black Hills for a distance of about 140 miles. The generalized section above, which has a greatly exaggerated vertical scale, shows the main lithologic units that have been traced and correlated, and the stratigraphic position of uranium deposits in various parts of the Black Hills in relation to these units. Geologists who have contributed to the diagrammatic section are listed on another part of this sheet and the areas for which each is responsible are shown on the accompanying map. The brief text below summarizes some of the broad stratigraphic relations within the Inyan Kara group and underlying formations.

South Dakota, Wyoming↗
USGS1954

Reconnaissance for uranium in black shale, Northern Rocky Mountains and Great Plains, 1953

Reconnaissance examinations for uranium in 22 formations containing black shale were conducted in parts of Montana, North Dakota, Utah, Idaho, and Oregon during 1953. About 150 samples from 80 outcrop localities and 5 oil and gas wells were submitted for uranium determinations. Most of the black shale deposits examined contain less than 0.003 percent uranium; however, thin beds of black shale at the base of the Mississippian system contain 0.005 percent uranium at 2 outcrop localities in southwestern Montana and as much as 0.007 percent uranium in a well in northeastern Montana. An eight-foot bed of phosphatic black shale at the base of the Brazer limestone of Late Mississippian age in Rich County, Utah, contains as much as 0.009 percent uranium. Commercial gamma ray logs of oil and gas wells drilled in Montana and adjacent parts of the Dakotas indicate that locally the Heath shale of Late Mississippian age contains as much as 0.01 percent equivalent uranium, and black shales of Late Cretaceous age contain as much as 0.008 percent equivalent uranium.

Idaho;Montana;North Dakota;Oregon;Utah↗