A study has been made of two deposits of Fe-Cu-Zn sulphide ores, from Gr¢sli and Eiker, in the Proterozoic Kongsberg Series of South Norway. The ores are located at the junction of acid-intermediate supracrustals and amphibolitized gabbros. The supracrustals underwent Upper Amphibolite facies metamorphism of Svecofennian age (1600 to 1500 m.y.B.P.) and were then intruded by the gabbros which underwent subsequent Sveconorwegian (1200 to 1000 m.y.B.P.) metamorphism at ~lid-Amphiboli te facies grade. The ore bodies were originally part of the supracrustal sequence, which was deposited as a volcano-sedimentary succession (with some hydrothermally altc:ced equivalents), similar to the KuroKo-type c1r.'posits of Japan. The ores have thus undergone both phases of h5[;h grade regional metamorphism. At Gr¢sli, the ores were partially incorporated in the gabbros prior to the later (Sveconorwegian) metar.lorphism, during which extensive shearing occurred throughout the ores at Eiker. The cores of the gabbroic intrusions retained original igneous mineralogies and textures, with progressive amphibolitization towards the peripheries. A subsequent Epidote-Amphibolite and later Greenschist facies grade overprint produced varying retrograde assemblages in the silicate rocks. Under Greenschist facies conditions, rejuvenation of the Sveconorwegian shear (at Eiker) caused brittle faulting, while fluid activity (at both Gr¢sli and Eiker) caused the formation of chloriteact ino.li te-carbo!)a.te assemblages around some of the ore bodies. Renobilisation of ~he ore material itself was minimal. Studies of R00thermometry and geobarometry indicate that the ore deposits were re-equilibrated during the Epidote-Ampllj boli te facies overprinting.

Investigations have been carried out for a number of cobalt deposits in Australia including three from the Mt Isa Block in Queensland, several deposits in New South Wales, and one deposit each in the Northern Territory and South Australia, with respect to the identification of cobalt-bearing mineralisation and possible modes of formation. The deposits studied cover a range of deposit and mineralisation types including hydrothermal (e.g., cobaltite, Esperanza, Queensland; arsenopyrite, Dome Rock, South Australia) and sedimentary (secondary mineralisation such as the manganese wads at Bungonia, New South Wales). Deposits that were studied previously by the author (MSc thesis) in the Mt Isa Block have been used for comparison of mineralisation and temperatures of formation. The determination of the temperatures of formation of mineralisation, in particular with respect to cobaltite and arsenopyrite, by means of the application of the FeAsSCoAsS-NiAsS ternary phase diagram and the arsenopyrite geothermometer, has helped lead to deductions concerning the modes of deposition. Other deposit features such as structural constraints and associated mineralisation aided in the formalisation of conclusions. Many of the deposits are hydrothermal in nature and contain high temperature phases including molybdenite and uraninite. The latter represent geochemical and mineralogical clues which show that many of the ores were emplaced by igneous processes associated with granites. The findings of this study suggest that despite high percentages of substituting species in arsenopyrite, derived temperatures, from the application of the binary and ternary geothermometers, are comparable. It was noted that the presence of pyrrhotite and/or löllingite to act as buffers in the system is an important constraint on the comparability of derived temperatures. Potential processing applications for the extraction of cobalt from ores are briefly discussed, with respect to the type and cobalt content of mineralisation identified. The Esperanza and the Selwyn copper-gold deposits show the greatest potential for economic cobalt recovery. / Doctor of Philosophy (PhD)

Thesis (M.S.)--University of Nevada, Reno, 2005. / "August, 2005." Includes bibliographical references. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

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.

Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "December, 2008." Accompanying CD-ROM contains appendices C and D. Appendix C: AutoCAD files with drill hole log; Appendix D: excel spreadsheet with copper mass balance calculations. Includes bibliographical references (leaves 206-215). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2009]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2000. / Bibliography: leaves 70-75.

Thesis (Ph. D.)--University of Oregon, 2003. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 211-235). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1940. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed March 8, 2010)

Thesis (M. Sc.)--University of Queensland, 2002. / Includes bibliographical references.

Ma On Shan Iron Mine was a only few economic deposit in Hong Kong for which have been closed for more than decades. There is lack of modern geological study of the mine. In order to understand the origin of the iron mine formation, microscopic and macroscopic study of underground were used in terms of field observation, thin section, Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS). In this study, ore formation is due to granitic magma contact with dolomitic marble which formed the Ma On Shan magnetite Skarn. Moreover, the mineral forming sequence is proposed. Magnetite and magnesium humite subgroup form in the early stage. Then the retrograde minerals are dominated by actinolite, tremolite fluorite and magnesium humite subgroup. In the late stage, some metallic minerals and rare earth mineral are disseminated within late stage vein, they are pyrite, cassiterite, scheelite and thorium/yttrium compound. Sellaite, cassiterite, scheelite, thorium/yttrium compound are newly discovered in Ma On Shan Iron Mine thanks to the modern technology. However, some common minerals have been mentioned by pervious authors are not found, e.g. garnet, this may due to the zonation and spatial distribution of mineral formation. / published_or_final_version / Applied Geosciences / Master / Master of Science