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Eugene Callaghan

Publications and source records attributed to Eugene Callaghan.

16 recordsLinked to original sources
USGS2014

Volcanic sequence in the Marysvale region in southwest‐central Utah

As a consequence of the detailed investigation of the alunite and other mineral deposits of the Marysvale Region in southwest‐central Utah, opportunity was afforded to map and study the succession of volcanic rocks that underlie most of this area. The Marysvale Region is part of a large area of volcanic rocks, which occupies much of the High Plateaus of Utah (Fig. 1). It is believed that the Marysvale Region covers sufficient area to furnish an adequate sample of this volcanic area, and, though horizontal variations are known to occur, the study may serve as a guide as to what may be expected in other parts of the area. The chemical analyses are the most completely representative of any ever taken in this part of Utah, and they furnish a basis of comparison within the High Plateaus and with other areas in Utah.

Utah↗
USGS1961

Geologic map of part of the Beaver quadrangle, Utah

Tertiary volcanic and intrusive rocks underlie a large area surrounding Marysvale in southwestern Utah. Part of the Beaver quadrangle and four complete 15-minute quadrangles, Marysvale, Delano Peak, Sevier, and Monroe, have been mapped to cover the areal extent of these rocks. Mapping in the Beaver quadrangle has been restricted to the northeastern part, the area containing the western part of this volcanic province. The mapped area of the quadrangle contains the westernmost slopes of the Tushar Mountains, which slopes steeply to the eastern edge of the Great Basin. The area is thoroughly dissected and its topography is extremely rugged, having a maximum relief of more than 3,500 feet. Wildcat, Indian, and North Creeks have developed the most prominent and steeply walled canyons. The area of about 42 square miles lies about 6 miles northeast of Beaver. A main nortb-south thoroughfare, United States Highway 91, connects Beaver with Salt Lake City 208 miles to the north. Roads in the canyons of Indian Creek and North Creek allow entry into the area. The geology of the Beaver quadrangle was mapped by Callaghan, but most of the report was written by Parker from field notes, previous reports, and oral data supplied by Callaghan.

Utah↗
USGS1956

Geologic map of the Gabbs magnesite and brucite deposits, Nye County, Nevada

During World War II the magnesite deposits at Gabbs, in northwestern Nye County, Nevada, were the source of ore for the world's largest magnesium metal plant. This Government-owned plant, located at Henderson, near Las Vegas, Nevada, close to the source of power at Boulder Dam, produced 81,272 tons of metal from 920,000 tons of ore during the period September 1942 to November 1944. Owing to the oversupply of magnesium toward the end of the war, mine production as a source for magnesium metal was curtailed and was finally stopped in November 1944. As of January 1947, 241,000 tons of magnesite from this area had been used in the production of refractories and oxychloride cement. Brucite deposits associated with the magnesite have been mined almost continuously since 1935 and had yielded 246,000 tons of ore through January 1945 for use in the refractoies industry of Ohio.

Nevada↗
USGS1948

Mineralogy and petrology of the currant creek magnesite deposits and associated rocks of Nevada

Cryptocrystalline magnesite occurs as relatively small dense, white masses in a Tertiary volcanic tuff, here named the Currant tuff, in White Pine and Nye counties, 29 miles southwest of Ely, Nevada. The deposits are small, but some of the magnesite is of very high quality with almost no iron or aluminum. However, much of the magnesite is mixed with dolomite and calcite, and a serpentinelike mineral occurs in one of the deposits in sufficient abundance to be of possible use in ceramics. In scattered areas the tuff has been altered by solutions rich in magnesium and bicarbonic acid to dolomite, magnesite, magnesium silicate, and calcite. Mineral and chemical characteristics are the same throughout the entire rock assemblage of flows and tuffs, suggesting that all the rocks have been derived from the same parent magma. The tuff formation, which ranges in thickness from a few feet to over 400 feet, occurs between two groups of volcanic flows here referred to as the lower volcanics and the upper volcanics. The lower volcanics is composed mainly of flows of hypersthene dacite, but in the southwestern part of the area flows of a hypersthene andesite of balsaltic habit occur between the dacite and the overlying Currant tuff. The upper volcanics which overlie the Currant tuff consist of porphyritic quartz latite and an overlying massive latite crystal tuff. The Currant tuff containing the magnesite has both unmodified and reworked tuff members. The formation of hydrothermal dolomite, magnesite, and deweylite is discussed in detail, and the physical chemistry of solutions containing calcium, magnesium, and carbon dioxide is applied in an explanation of the origin of magnesium-rich solutions.

Nevada↗
USGS1938

Manganese deposits of the Drum Mountains, Utah

More than 15,000 tons of manganese ore has been produced from small deposits in the Drum Mountains in west-central Utah. Lenses of rhodochrosite, now largely weathered near the surface to manganese oxides, lie parallel to the bedding of Cambrian dolomites and shales near faults that are nearly normal to bedding. Two varieties of rhodochrosite, one fine-grained, dark-gray or black, and massive, the other coarser-grained, pink, and generally occurring in veinlets in the gray variety, are present. The gray contains less MnCO 3 and FeCO 3 , but more CaCO 3 and MgCO 3 than the pink variety. The deposits are interpreted as bodies that replaced favorable dolomite or limestone beds. The gray rhodochrosite first replaced the dolomite or limestone; the pink variety later formed veinlets in the gray rhodochrosite and replaced it to a small extent.

Utah↗