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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Hydrogeochemistry of springs near the Eustis Mine, Quebec

Hoag, R. B. (Roland Boyden), 1945- January 1975 (has links)
No description available.
102

Evaluation of procedures for recovering manganese from a Carroll County, Virginia, ore

Merrill, David L. January 1956 (has links)
Manganese is a metal of strategic importance which is vital to the steel industry. In the production of steel, the two main uses of manganese are as a deoxidizer and as an alloying constituent. Approximately 13 pounds of manganese are used for each ton of steel, and for this use alone, the requirement of the United States in 1956 will approach two million tons of ferromanganese ore. In 1954, the United States imported over 90 percent of its manganese requirements and if these sources become unavailable, this nation will be dependent to a great extent upon abundant low-grade ores. A sample of the head ore from the Betty Baker Mine, Great Gossan Lead, Carroll County, Virginia, analyzed 0.82 percent acid soluble manganese. An analysis of the tailings from flotation of this complex sulfide ore revealed a total manganese content of approximately three percent of which two-thirds is acid soluble. The remaining one percent is in the form of a silicate-aluminate gangue which is acid insoluble. Mechanical methods such as froth flotation, sink float, and magnetic separation have not been too effective in upgrading the ore from Carroll County. Chemical procedures, such as roasting, leaching, and electrodeposition, were thought to offer a better means for the recovery of manganese from the beneficiated ore or tailings. It was the purpose of this investigation to evaluate procedures for chemically converting the manganese compounds in the tailings, from bulk sulfide flotation of the Carroll County ore, to soluble salts from which the manganese could be recovered electrolytically. / Master of Science
103

Trace element characteristics of zircon : a means of assessing mineralization potential of intrusions in northern Nevada

Farmer, Lucian P. 29 November 2012 (has links)
Oxidized hydrous intermediate composition magmas are responsible for porphyry copper (Cu ±Mo ±Au) deposits and epithermal Au ore deposits formed globally in the shallow crust (Sillitoe, 2010; Seedorff et al., 2005). Recently, zircon geochemistry has been used to characterize both productive and barren intrusions associated with porphyry Cu-Au ore deposits. Zircon composition differs slightly between the two intrusive groups, and researchers have proposed that zircon in productive intrusions has crystallized from a relatively more oxidized melt compared to barren intrusions (Ballard et al., 2002; Muñoz et al., 2012). Zircon rare earth elements record anomalies in Ce and Eu contents that allow estimation of the ratio of oxidized versus reduced species, i.e. Ce⁴⁺/Ce³⁺ (Ce[superscript IV]/Ce[superscript III]) and Eu³⁺/Eu²⁺ (Eu/Eu*)[subscript CN]. This study focuses on understanding the compositions of Eocene magmas associated with sediment hosted Carlin gold deposits and the gold-copper ores of the Battle Mountain porphyry Cu-Au-skarn district in northern Nevada. Zircon trace element composition was analyzed using LA-ICP-MS and SHRIMP-RG to determine differences between mineralizing and non-mineralizing intrusions in northern Nevada and to compare these compositions with known porphyry Cu-Au type magmas. These zircon and rock compositional data was then used to test the hypothesis of a magmatic origin of the Carlin type gold deposits (Muntean et al., 2011). Zircon U-Pb ages were calculated using multiple SHRIMP-RG spot analyses of each sample for two Carlin biotite porphyry dikes, two Battle Mountain porphyry dikes and the granodiorite of the Copper Canyon stock. The new U-Pb age dates for Carlin porphyry dikes are 38.7 ± 0.5 Ma and 38.8 ± 0.4 Ma. The age of the Copper Canyon stock is 38.0 ± 0.7 Ma, and the age of the Battle Mountain porphyry dikes are 40.2 ± 0.4 Ma and 41.3 ± 0.4 Ma. The Carlin dike ages are the same age, within uncertainty, with previous studies conducted (Mortensesn et al., 2000). The productive porphyry dikes from the Battle Mountain district have Ce(IV)/Ce(III) ratios of 500 to 10000 and a wide range of (Eu/Eu*)[subscript CN] values between 0.3 and 0.7 respectively. Carlin porphyry dikes have Ce(IV)/Ce(III) values between 100 and 1000, and a more limited (Eu/Eu*)[subscript CN] range of 0.5 to 0.7. Barren Eocene intrusions at Harrison Pass and Caetano have much lower Ce(IV)/Ce(III) ratios that range from 20 to 500, and have a very large span of (Eu/Eu*)[subscript CN] from 0.03 to 0.6. Calculated Ce(IV)/Ce(III) and (Eu/Eu*)[subscript CN] of zircon of this study illustrate a distinction between productive and barren intrusions in northern Nevada, and demonstrate a geochemical link between porphyry type magmas and dikes associated with Carlin type gold deposits. These ratios may provide a useful means of evaluating potentially economic geologic terranes and serving as a method to infer relative oxidation state of zircon bearing intrusive rocks. / Graduation date: 2013
104

Tungsten occurrences in Arizona and their possible relationship to metallogenesis

Myers, Genne Marie, Myers, Genne Marie January 1983 (has links)
No description available.
105

The geology and ore deposits of a portion of the Tyndall Mining District, Santa Cruz County, Arizona

Walchessen, Anne Aurelia January 1983 (has links)
No description available.
106

The geology and ore deposits of a portion of the Harshaw district, Patagonia Mountains, Arizona

Kartchner, Wayne E., 1908- January 1944 (has links)
No description available.
107

Economic geology of the Alamos Mining District, Sonora, Mexico

Vazquez Perez, Adalberto, 1944- January 1975 (has links)
No description available.
108

The geology and ore deposits of a portion of the Harshaw district, Santa Cruz County, Arizona

Moores, Richard Charles, 1946- January 1972 (has links)
No description available.
109

The geology and ore deposits of the Mowry Mine area, Santa Cruz county, Arizona

Smith, George Edward, 1929- January 1956 (has links)
No description available.
110

Multisensorsystem für die automatisierte Detektion von Gangerzlagerstätten und seltenen Erden in einer Mine

Varga, Sebastian 29 July 2016 (has links) (PDF)
Im Rahmen von UPNS4D+ wird von mir der Teilbereich der automatisierten untertägigen Detektion von Gangerzlagerstätten und seltenen Erden bearbeitet. Dies erfolgt mittels eines Multisensoransatzes, der aus einer Hyperspektralkamera, einer RGB-Kamera und einem Laserscanner besteht. Die Grundlagen für die Kombination von hyperspektraler Bildverarbeitung und einer RGB-Kamera sind in der Industrie im Bereich von automatisierten Sortieranlagen zu finden. Im Bereich der Fernerkundung ist der Einsatz hyperspektraler Bilder für die Detektion geologischer Merkmale seit einigen Jahrzehnten üblich. Hier kann im Rahmen meiner Forschung gezeigt werden, dass mittels hyperspektraler Bilder Pyrit unter Tage detektiert werden kann. / In my research I work on a system which detects automatically the ore and rare earth element in a mine. This is part of UPNS4D+. For the detection I use a multi sensor system which consists of a hyperspectral camera, a RGB camera and a Laser scanner. Basics of this combination can be found in the industry. The combination of a RGB camera and a hyperspectral camera enables an automatic sorting of for example waste materials. Landsat satellites in the 1970 uses spectral information in order to detect the geology of the surface. I have tested the hyperspectral imaging in the Reiche Zeche and I can now show that Pyrite can be detected.

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