Thesis (M.S.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed July 30, 2007. Includes bibliographical references (p. 53-57).

Thesis (M.S.)--Oregon State University, 1986. / Typescript (photocopy). Eight maps and twelve ill. folded in pocket. Includes bibliographical references (leaves 79-83). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1986. / Typescript (photocopy). Two maps folded in pocket. Includes bibliographical references (leaves 121-130). Also available online.

Please read the abstract in the section 00front of this document / Dissertation (MSc)--University of Pretoria, 2006. / Geography, Geoinformatics and Meteorology / Unrestricted

Maps in pocket.

At the north end of the Kootenay Arc, isolated patches of gritty quartzite of the upper Lardeau Broadview Formation (Ord.?) lie in the core of a northwesterly trend-in structure, the Illecilleweat Synform. These rocks overlie, in tectonic contact, black, carbonaceous phyllite of the lower Lardeau Index Formation (lower to middle Ord.). The contact is enclosed in a zone of highly sheared and recrystallized rocks designated here as a phyllonite zone. The Broadview rocks were thrust into juxtaposition with the Index during an early phase of isoclinal, recumbent folding which correlates with the development of nappe structures during deformation along the Kootenay Arc. Interstratal formations of the middle Lardeau were sheared out. The phase was accompanied by regional metamorphism of greenschist grade which aided recrystallization and reoientation of quartz and mica. Similar folding, nearly co-axial with Phase 1 and accompanied by waning metamorphism, folded, tightened, and reactivated earlier-formed structures. This resulted in transposition of lithology and the asymmetric Illecillewaet Synform. The relative age of the Broadview, which is very similar lithologically to Horsethief Creek elastics of Windermere age, has not been established from this study. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Seventy-one samples of subalkaline and alkaline basalts from British Columbia and the adjacent Pacific seafloor were analyzed for 33 major, trace and rare earth elements using X-ray flourescence (XRF) and instrumental neutron activation analysis (INAA). These basalts are all less than 22 Ma in age and come from various magmatic belts, each with a distinct, well-known, tectonic setting; (1) Convergent margin (Garibaldi and Pemberton Belts), (2) Back-arc (Chilcotin Basalts), (3) Hotspot (Anahim Volcanic Belt), (4) Incipient rift (Stikine Volcanic Belt), (5) Arc-trench gap (Alert Bay Volcanic Belt) and (6) Ocean floor (Offshore basalts of the Juan de Fuca-Explorer Ridge Systems). Element abundances and ratios were plotted on eighteen diagrams that have been proposed to discriminate between tectonic settings on the basis of magma chemistry. Although eruption through continental crust has modified the abundances of Ba, Th, U, K and Sr, in most cases this did not affect the ability of the diagrams to distinguish tectonic setting. On most diagrams basalts from back-arc, hotspot, incipient rift and arc-trench gap settings plotted in the within plate basalt (WPB) field, but distinction between these different WPB settings could not be made. Two samples from the Masset Formation on the Queen Charlotte Islands, included with the Anahim Belt hotspot suite, were consistently classified as convergent margin. Samples from the ocean floor plotted in the N-MORB or E-MORB fields. Three convergent margin samples from the Pemberton Belt always plotted in the convergent margin field, but on most diagrams all eight samples from the Garibaldi Belt plotted in the WPB field because of their depletion in LIL elements. La is the only rare earth element obtained by INAA that is essential for identifying the tectonic environment of magma genesis. The ratio La/Nb, is an effective separator of within plate basalts (WPB), including E-MORB, (La/Nb less than 1.2) from convergent margin basalts (La/Nb greater than 2.0). N-MORB lie between the ratios 1.2 and 2.0. Th, Ta and Hf also obtained by INAA, are important discriminant elements. However, Nb and Zr, obtained by XRF analysis convey much of the same information. The ratio Nb/16 as an estimate of Ta and Zr/39 as an estimate for Hf produced acceptable results on diagrams that originally incorporated Ta and Hf. Effective discrimination can therefore usually be achieved using XRF elements alone. Convergent margin, within plate and ocean floor tectonic settings were best distinguished on Th-Hf/3-Ta, Ti-Zr-Y and Ti-Zr-Sr, Ti/Y vs. Nb/Y, Th/Yb vs. Ta/Yb, (Ba/La)CH vs. (La/Sm)CH and V vs. Ti/1000. Slightly less effective plots were MnO-Ti0₂-P₂0₅, La vs. Th, La vs. Nb and K₂0/Yb vs. Ta/Yb. On the other hand Ti0₂-K₂0-P₂0₅, MgO-Fe0*-Al₂0₃ and La vs. Ba provided little information concerning the tectonic setting of individual samples. Ti/Cr vs. Ni, Sm/Ce vs. Sr/Ce, Cr vs. Ce/Sr and Cr vs. Y diagrams were useful for distinguishing unfractionated convergent margin basalts from MORB plus WPB. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, October 2018 / Mashitu South is a Cu-Co deposit situated in the Katanga Province of the Democratic Republic of the Congo (DRC), about 25km to the east of the city of Kolwezi. It lies within the northwestern portion of the Central African Copperbelt (CAC), an arcuate region with a world class abundance of copper deposits that straddles the external-fold-and-thrust-belt and the Domes region of the Lufilian arc, an orogenic belt that formed during the ∼600-500Ma Pan African orogeny. Cu-Co mineralisation at Mashitu South is hosted in the rocks of the Mines Series and Roches Argillo-Talceuses (RAT) subgroups of the Roan Group, deposited during the early stages of the opening of the Katangan basin, which is constrained to a maximum age of ∼880Ma. This study characterises the mineralisation stages and geochemistry of Mashitu South through a combination of core logging, geostatistical and petrographic techniques. The mineralogical and geochemical changes which occurred to the deposit throughout its paragenetic history are also explored. This is done with the purpose of linking the mineralisation at the deposit to regional metallogenic and geodynamic events, as well as developing vectors to Cu-Co mineralisation. Mineralisation at Mashitu South occurred in four stages. The first stage is characterised by the development of stratiform-disseminated, zoned Cu-Co sulphides restricted to the rocks of the Mines Series, in a manner comparable to the sedimentary hosted stratiform copper (SSC) deposit model. A protracted, syn-diagenetic timing is inferred for this stage, which caused the formation of hypogene, stratiform orebodies, primarily in the Kamoto Formation. Metals emplaced during the first stage were remobilised during the second mineralisation stage, which resulted in the development of vein-hosted hypogene Cu Co sulphides, but does not appear to have concentrated metals into significant orebodies at Mashitu South. The second period of mineralisation is inferred to be early/syn-orogenic in age. Hypogene mineralisation at Mashitu South is found to have an element association of Cu + Co + Bi + Ni + V + S ± Mo ± As ± Fe ± Zn. The deposit was subsequently affected by two discrete stages of supergene alteration and mineralisation. Supergene alteration has resulted in the in-situ oxidation of hypogene Cu-Co sulphides, and also the leaching and remobilisation of metals from hypogene mineralisation. The leaching and remobilisation process formed supergene, malachite-dominated orebodies which have an element association of Cu + Be + P ± Zn, the location of which is primarily controlled by metal availability and permeability of the host rocks. The RAT Subgroup is frequently host to such orebodies, underneath leached and eroded away Mines Series strata. These orebodies are usually found at a depth of ∼30 50m. An occurrence of bacillus-shaped features composed of Cu-Co sulphides was discovered in the lower Shales Dolomitique du Base (SDB) unit of the Mines Subgroup, and investigated with respect to the potential biogenicity and antiquity of the features as candidate microfossils. Further study found these features to be pseudofossils formed primarily by the replacement of diagenetic rutile crystals by sulphides, during the primary, stratiform mineralisation stage. The various elements of the hypogene geochemical association are shown to have different mobilities in the supergene leaching environment, with Cu being relatively mobile and Co + Bi + Ni + V ± Mo being relatively refractory. This variation in mobility between elements, which are associated with Cu in the hypogene environment, suggests a zonation of these elements around Cu in the supergene environment, controlled by the hydrological gradient. At Mashitu South, this has resulted in the relative enrichment of Bi, Mo, V and Co in the upper 10m of the rock profile. Nickel is not as depleted in this interval as Cu, which is strongly depleted in the near-surface environment. It is therefore hypothesised that Bi, Mo, V, Co and Ni would make better surface vectors towards buried Cu-Co mineralisation than Cu, in regions where the supergene leaching process is particularly effective. ‘Cobalt caps’ above Cu-Co deposits in Katanga are well known, but this study suggests that Bi, Mo and V may make even better surface vectors to mineralisation than Co. / XL2019

Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2005. / Restricted until October 2008. Bibliography: leaves 224-244. Also available online.