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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.
91

Accounting for non-stationarity via hyper-dimensional translation of the domain in geostatistical modeling

Cuba Espinoza, Miguel Angel. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Feb. 19, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Mining Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.
92

Beneficiation of Phalaborwa phosphate rock

Mostert, Josua Cornelis, 1934- January 1959 (has links)
No description available.
93

STRUCTURAL CONTROLS OF Ni-Cu-PGE ORES AND MOBILIZATION OF METALS AT THE GARSON MINE, SUDBURY

Mukwakwami, Joshua 24 January 2014 (has links)
The Garson Ni-Cu-PGE deposit is located on the South Range of the 1850 Ma Sudbury structure along the contact between the Sudbury Igneous Complex (SIC) and the underlying metasedimentary and metavolcanic rocks of the Paleoproterozoic Huronian Supergroup. It comprises four ore bodies that are hosted by E-W-trending shear zones that dip steeply to the south. The shear zones formed as south-directed D1 thrusts in response to flexural-slip during regional buckling of the SIC. They imbricated the ore zones, the SIC norite, the underlying Huronian rocks and they emplaced slivers of Huronian rocks and anatectic breccia into the overlying Main Mass norite. Coexisting garnet-amphibole pairs yielded syn-D1 amphibolite facies metamorphic temperatures ranging from ~550°C to 590°C. The shear zones were coeval with the moderately southdipping South Range and Thayer Lindsley shear zones, which formed to accommodate the strain in the hinge zone as the SIC tightened with progressive D1 shortening. The SE limb of the SIC was overturned together with the D1 thrusts, which were then reactivated as steeply south-dipping reverse shear zones during syn-D2 greenschist metamorphism.Syn-D2 metamorphic titanite yield a U-Pb age of ca. 1849 ± 6 Ma, suggesting that D1 and D2 are part of a single progressive deformation event that occurred immediately after crystallization of the SIC during the Penokean Orogeny. The ore bodies plunge steeply to the south parallel to the colinear L1 and L2 stretching mineral lineations. Ore types consist mainly of pyrrhotite-pentlandite-chalcopyrite breccia ores, but also include pyrrhotite-pentlandite-chalcopyrite disseminated sulfide mineralization in norite, and syn-D2 quartz-calcite-chalcopyrite-pyrrhotite-pentlandite iv veins. In the breccia ores, matrix sulfides surround silicate rock fragments that have a strong shape-preferred orientation defining a pervasive foliation. The fragments are highly stretched parallel to the mineral lineations in wall rocks, suggesting that the ore bodies are zones of high strain. Pyrrhotite and chalcopyrite occur in piercement structures, in boudin necks between fragments, in fractures in wall rocks and in fold hinges, suggesting that the sulfides were mobilized by ductile plastic flow. Despite evidence of high strain in the ore zones, the sulfide matrix in D1 and D2 breccia ores show little evidence of strain as they consist predominantly of polygonal pyrrhotite aggregates, suggesting that they recrystallized during, or immediately after D1 and D2. However, rare elongate pyrrhotite grains aligned parallel to S2 are locally preserved only in D2 breccia ores. Exsolution of pentlandite loops along grain boundaries of elongate pyrrhotite formed S2-parallel pentlandite-rich layers in D2 breccia ores, whereas the pentlandite loops are multi-oriented in D1 contact breccia as they were exsolved along grain boundaries polygonal pyrrhotite. Because exsolution of pentlandite post-date D1 and D2, and that individual pentlandite grains neither have a shape-preferred orientation nor show evidence for cataclastic flow, the sulfides reverted to, and were mobilized as a homogeneous metamorphic monosulfide solid solution (mss) during D1 and possibly D2. This is in agreement with predictions from phase equilibria as the average Garson composition plots within the mss field in Fe-Ni-S ternary diagram at temperatures above ~400°C. Disseminated and breccia ores at Garson have similar mantle-normalized multi-element chalcophile patterns as undeformed contact-type disseminated and massive ore, v respectively, at the well known Creighton mine in the South Range. This suggests that the Garson ores are magmatic in origin and that their compositions were not significantly altered by hydrothermal fluids and deformation. The lack of variations in Ni tenors between the disseminated and breccias ores suggest that the R-factor was not the process controlling metal tenors because the disseminated sulfides do not consistently have higher metal tenors than the breccia ore. The breccia ores are enriched in Rh-Ru-Ir and are depleted in Cu-Pd-Pt-Au, in contrast to footwall-type ore at the nearby Garson Ramp mine which is enriched in the same metals. When Ni100, Rh100, Ir100, Pt100 and Pd100 are plotted against Cu100, the breccia and footwall-type ore analyses plot along model mss fractionation and sulfide melt model curves, suggesting that these two ore types are related by mss fractionation. In summary, the Garson breccia ores are mss cumulates that settled quickly at the base of the SIC via a gravity filtration process, and were mobilized as a metamorphic mss by ductile plastic flow during D1 and D2. Despite minor local hydrothermal mobilization of some metals, the study confirms findings from other studies that highly deformed Ni-Cu-PGE deposits, such as the Garson deposit, can provide important information on the genesis of the deposits.
94

The carbonatite-hosted apatite deposit of Jacupiranga, SE Brazil: styles of mineralization, ore characterization and association with mineral processing

Alves, Paula Regina, January 2008 (has links) (PDF)
Thesis (M.S.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed May 9, 2008) Includes bibliographical references (p. 131-139).
95

Ore types of the Barrier Ranges : a study.

Williams, Roy Ernest. January 1900 (has links) (PDF)
Thesis --University of Adelaide, Faculty of Science. / Typewr. copy.
96

A comparison of various methods of assaying cyanide solutions for gold

Dunn, Theodore Saunders. January 1910 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1910. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed March 17, 2009) Includes bibliographical references (p. 26).
97

Mining and milling of a low grade copper ore

Armstrong, Richard Edward. Johnson, Horace Asahel. January 1908 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1908. / The entire thesis text is included in file. Typescript. Illustrated by authors. R. E. Armstrong determined to be Richard Edward Armstrong and H. A. Johnson determined to be Horace Asahel Johnson from "Thirty-Seventh Annual Catalogue of the School of Mines and Metallurgy". Title from title screen of thesis/dissertation PDF file (viewed November 12, 2008) Includes bibliographical references (p. 31).
98

The treatment of a gold-silver-copper ore by the Argo process

Heck, Elmer Cooper. Brown, Josephus Jarvis. January 1905 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1905. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed November 18, 2008)
99

Contact plane concentration

Rogers, John A. Dean, George Walter. January 1897 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1897. / The entire thesis text is included in file. Typescript. Illustrated by authors. Jno. Rogers determined to be John A. Rogers and G. W. Dean determined to be George Walter Dean from "Forty-First Annual Catalogue. School of Mines and Metallurgy, University of Missouri". Title from title screen of thesis/dissertation PDF file (viewed February 12, 2009)
100

The viability of the Kaplats Platinum group element deposit

Carroll, Sandy. January 2006 (has links)
Thesis (M.Sc.(Geology))--University of Pretoria, 2006. / Includes bibliographic references.

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