Thesis (MAppSc(ChemTech))--University of South Australia, 2000

Thesis--University of Missouri, School of Mines and Metallurgy, 1910. / The entire thesis text is included in file. Typescript. Walter I. Phillips determined to be Walter Irving Phillips from "Forty-First Annual Catalogue. School of Mines and Metallurgy, University of Missouri." Title from title screen of thesis/dissertation PDF file (viewed March 24, 2009) Includes bibliographical references (p. 12).

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1902. / C. E. Martinez determined to be Carlos E. Martinez from "1874-1999 MSM-UMR Alumni Directory". The entire thesis text is included in file. Typescript. Illustrated by authors. Title from title screen of thesis/dissertation PDF file (viewed October 29, 2008)

Thesis (M.Sc.) - Carleton University, 2002. / Accompanying material: 2 maps in pocket. Includes bibliographical references (p. 119-127). Also available in electronic format on the Internet.

Thèse (D.R.M.)--Université du Québec à Chicoutimi, 1991. / Document électronique également accessible en format PDF. CaQCU

Thèse (M.Sc.T.) -- Université du Québec à Chicoutimi, 2002. / Bibliogr.: f. 179-185. Document électronique également accessible en format PDF. CaQCU

Thesis (M.S.)--University of Puerto Rico, Mayagüez Campus, 2005. / Tables. Printout. Includes bibliographical references (leaves 130-135).

From Introduction: For at least two centuries and a corresponding number of generations of geologists and miners there has been active argument concerning the origin of certain types of carbonate hosted mineral deposit. The characterization of the type itself was and still is debatable. Objections have been raised to grouping several examples under one heading because each has its individually distinctive features. ·This is especially applicable to the carbonate hosted lead-zinc "sedimentary" deposits. The type that will be discussed in the text to follow is composed chiefly of galena, sphalerite, barite and fluorite, with pyrite , marcasite and chalcopyrite as conspicuous accessory ore minerals. Exceptions to this general copper deficient characteristic displayed by the sedimentary carbonate-hosted lead-zinc deposits are the deposits at Tsumeb and Kombat, Namibia. These deposits are hosted by the carbonate sequence of the Otavi Shelf sediments, and copper, in the form of tennantite, chalcopyrite and bornite, is the major ore constituent. Calcite, aragonite, dolomite and quartz are the commonest nonmetallic gangue minerals but siderite and silica may also be present. In contrast with other lead and zinc sulphide (volcanogenic) deposits, those to be considered here seldom carry noteworthy amounts of silver or any other precious metals. Commonly the country rock is a carbonate; limestone or dolomite, but deposits in. sandstone, shale and conglomerate are not unknown. Characteristic features are ore bodies that extend parallel or nearly so with the bedding although many such deposits are partly, or completely developed along crosscutting fissures and breccias. Some observers regard these fissure fillings as evidence for a magmatic source of the metals, whereas others regard them as an indication of remobilization of ions, metals or minerals orginally present in low-grade stratiform deposits elsewhere in the stratigraphic succession.

The exotic orebodies related to cal-alkaline porphyry copper deposits. are sub-horizontal lenticular bodies of secondary copper minerals that impregnate Tertiary gravels and bedrock of different ages. They lie immediately downslope of the porphyry copper deposits, that is to say. they are related to the propylitic halo of the main deposits, and are considered to have originated with the deposition of copper minerals from solutions that overflowed during the secondary enrichment process. Supergene alteration took place between the late Oligocene and Miocene, by which time both orehodies (exotic and porphyry copper) were established. The paucity of tile denudation since the Miocene in the Andean segment from 21º to 26º latitude S. due to the dominance of a hyperarid climate explains the remarkable preservation of the shallow porphyry copper systems, supergene enriched blankets and associated deposits. This is reflected in the limonites, where the typical boxworks have been partially or totally destroyed on surface by the superleaching. As a result of the lateral migration of the copper-bearing solutions, the exotic deposits show a zonation. alteration and mineralization whose characteristics depend among other factors. on the reactivity of the bedrocks and the Cu/S ratio of the mother deposit. In these deposits three zones can be recognized: Proximal (0 to 2 km Intermediate (2 to 3) and Distal (3 to 8-14 km) with palaeodrainage control. The associations and mineralogical abundance are related to the climate (rain. temperature). In some deposits two important units are detected and they are the Cu-phosphates and Cu-lixiviable (to sulphuric acid) units. The size of tile Chilean exotic deposits varies between 100 and 3.500.000 tons of copper, with a total known resource of 8 M tons of copper. The large exotic deposits are comparable to the resources of a medium-sized porphyry copper- type deposit. The discovery of the exotic deposits is related to the exploration of porphyry copper deposits, where a mass balance of the leached column must be done. Moreover the lithology and alteration of the propylitic halo. permeability, structures, geophysics and geochemistry should be considered. The diorite model is not compatible with a supergene enrichment process, expressed by the absence of colour anomalies, exotic deposits and in the presence of secondary minerals like jarosite, which is coherent with the pyrite deficiency of the system. The projects are for exploitation of reserves by open pit methods. The projects plan to extract and to crush copper oxide ore which will he pre-treated with concentrated sulphuric acid prior to heap leaching, solvent extraction and electrowinning. The copper output varies between 10,000 and 50,000 ton per year of catilode copper. The total investment varies between 20 and 100 millions dollars. For project calculations, estimation of 65 % - 82 % copper recovery and 37 - 40 kg/ton net acid consumption can be used due to the nature of ore. The leaching time is estimated as 30 to 180 days for heaps of 4,5 to 30 metres high. As a result of this, the plant capacity is determined by an annual equivalent of 10,000 to 25,000 ton Cu per year. Pit planning has heen carried out using diverse software on the basis of 5 x 5 x 5 m and 10 x 10 x 10 m block models, evaluated using a kriging package built into the program, giving an overall waste/ore ratio (induding pre-stripping) of 0: I (in an outcrop) to 3: I. The location of the mine and plant sites are associated with the porphyry copper in production, for this the already installed facilities can be used. So there is no need to build a new mine camp or access. The environmental impact is summarized relating to the characterization of the physical, biological and socio-cuitural effects, using the framework of the Base Line study and the Impact evaluation derived from the construction and project operation phases. The conclusions and recommendations will diminish, mitigate and/or eliminate impact derived from the specific activities.

The thesis is divided into two parts. In Chapter I a new bedded copper deposit at Redstone River, N.W.T., is described for the first time. Emphasis is placed on those aspects of the geology, mineralogy and mineralography which may have significance in considering the origin of the ore. It is concluded that the ores were emplaced at low temperature subsequent to deposition of the host rock. Some redistribution and possibly addition of copper occurred at a later date as a result of tectonic disturbance. In Chapter II the problem of the origin of red bed copper deposits is discussed with the Redstone deposit considered as a typical example. An attempt is made to review the major aspects of the problem, including what the writer considers to be the most important ideas expressed in the literature. The writer discards the terms 'epigenetic' and 'syngenetic1 as applied to such deposits and proposes new lines of research based on the difference in electric potential between host rocks and adjacent red beds. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate