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F. B. Moore

Publications and source records attributed to F. B. Moore.

4 recordsLinked to original sources
USGS1961

Sandstone-type uranium deposits at Ambrosia Lake, New Mexico-An interim report

The Ambrosia Lake district in northwestern New Mexico is the most important uranium mining and milling district in the United States. Together with the nearby Laguna district it contains more than 50 percent of the nation's reserves.Most of the ore occurs in the Morrison formation of Late Jurassic age as elongate, tabular, mantolike bodies principally in the upper half of the Westwater Canyon sandstone member and near the base of the Poison Canyon sandstone tongue (9). Individual deposits are distributed along two easterly trending belts 2 to 3 miles apart. The ore bodies are as much as 3,000 feet long, several hundred feet wide, and 100 feet thick. Depths to the ore range from 0 to 2,200 feet. Some ore is also mined from the Todilto limestone of Late Jurassic age and from the Dakota sandstone of Early (?) and Late Cretaceous age.Two types of unoxidized ore are recognized: prefault ore, which is considered to be primary, and postfault ore, which may be redistributed. The prefault ore shows no obvious relationship to tectonic structures but appears to be controlled by a variety of sedimentary structures. Postfault ore is controlled by a combination of sedimentary and tectonic structures. Disseminated carbonaceous matter, believed to be plant derived, appears to be the dominant control in the localization of the uranium .The ore mineralogy is comparatively simple, and coffinite is by far the most abundant ore mineral. Molybdenum, selenium, vanadium, and iron occur in anomalous quantities in the deposits in both oxidized and unoxidized minerals.U/eU ratios and radioisotope distribution indicate almost universal disequilibrium and fairly recent migration of radioisotopes in all deposits that have been sampled.Further studies on the organic carbonaceous matter, sandstone alteration, age determinations, and sulfur isotope composition are required to obtain a better understanding of the source, transportation, and deposition of uranium and other elements in the deposits .

New Mexico↗
USGS1954

Geology and uranium deposits of the Caribou area, Boulder County, Colorado

Pitchblende was discovered in the Caribou mine, Boulder County. Colo., in 1948 by Consolidated Caribou Silver Mines, incorporated during the reopening of the 1040-level. Since 1948, a small quantity of pitchblende has been produced from the Radium vein during exploratory work that was done under contract with the Atomic Energy Commission. The Caribou mine, primarily a silver mine, develops five veins (Caribou. No Name, Poorman, Sherman and Silver Dollar) that were formerly worked as separate mines. Three other veins, the Radium, Elmer, and Nelson, are exposed in the Caribou mine only at and below the 920-level. The general geology of the Caribou area, known since 1869 as a silver district, has been discussed by Bastin and Hill (1917) and more recently by Lovering and Goddard (1950). In 1937 a detailed study of the petrography of the Caribou stock was made by Smith (1938). In 1948 and 1949, R.U. King (1950) of the U. S., Geological Survey examined the Caribou mine to evaluate the uranium deposit. In 1950, D.M. Sheridan and E.N. Hinrichs of the U. S. Geological Survey made a radioactivity reconnaissance of the mine dumps at Caribou and vicinity. This reconnaissance included examination of most of the accessible workings of the Caribou mine. Other reports on the area are listed in the bibliography. As a result of King’s preliminary examination and the later exploration for uranium on the property, the U.S. Geological Survey in 1951 began a detailed investigation of the Caribou area on behalf of the Division of Raw Materials of the Atomic Energy Commission, the principal purpose of which was to evaluate the uranium occurrences in the area. The study was begun by E. P. Kaiser and W. S., Cavender, who established a triangulation net, using a base line in Caribou Park for horizontal control and a U.S. Geological Survey bench mark on the top of Caribou Hill for vertical control. Upon the assignment of Kaiser to another project in August 1951 the investigation was continued until November 1951, by F.B. Moore and W. S. Cavender. During the study of the district the writers prepared a geologic map at a scale of 1 inch to 100 feet of an area of about one square mile. The mapped area includes most of the mines in the Caribou district and embraces the eastern half of Caribou Hill and adjacent areas to the east and north. In addition, all accessible underground workings were mapped at a scale of 1 inch to 40 feet. The writers wish to acknowledge the cooperation of the staff of the Consolidated Caribou Silver Mines incorporated, who made the Caribou mine available for examination at all times and who furnished maps and suggestions that were of great assistance. Mr. A.E. Blakesley, owner of the Comstock mine, was also most cooperative in making possible the examination of his mine. Thanks are due Dr., E.E. Wahlstrom of the University of Colorado and to the Boulder Daily Camera for the use of their files containing information on the Caribou mine. To S. Lovering of the U.S. Geological Survey made many valuable suggestions on the identification of alteration products in thin section.

Colorado↗
USGS1953

Uranium in the metal-mining districts of Colorado

Many varieties of abnormally radioactive rocks and ores have been found in Colorado as a result of more than eight years of geologic studies by the U. S. Geological Survey, but only a small proportion of these contain uranium in sufficient quantities to be of possible commercial interest.

Colorado↗