The Holloway mine is an Archean lode gold deposit hosted within the southwestern Abitibi greenstone belt. Rocks hosting the deposit are bounded by two main branches of the Destor Porcupine fault zone and belong to the Destor Porcupine Complex. Meta-volcanic rocks of the Destor Porcupine Complex were tested using the Treuil method and shown to belong to a tholeiitic suite that differentiated via fractional crystallization producing three distinct groups: tholeiitic meta-basalts, Fe-tholeiitic meta-volcanic rocks, and variolitic meta-volcanic rocks. Alteration at the Holloway deposit consists of a silicified and albitized core surrounded by halos of sericite and carbonate alteration. Carbonate alteration is composed mainly of ankerite and appears pervasive due to many overlapping hydrothermal events. Lightning Zone mineralization is the earlier of two gold mineralizing events. It is associated with finegrained disseminated pyrite and hosted by silicified and albitized variolitic meta-volcanic rocks having variolitic and hyaloclastite textures. Results from statistical factor analysis show that gold-bearing hydrothermal fluids contain S, W, and sometimes As. Both episodes of gold mineralization only occur within meta-volcanic rocks that have a Fe/Mg = 8. (Abstract shortened by UMI.)

A new data set of 53 $\sp‡$Sr/$\sp†$Sr ratios for the Lower Devonian has been collected from well preserved, and stratigraphically well constrained, brachiopod shells from the Leon region in Spain, western Urals in Russia, Podolia in Ukraine and New York State in the United States. Multiple criteria, including trace element and stable isotope (C, O) analysis, scanning electron microscopy, cathodoluminescence and optical light microscopy, were used to determine the state of preservation of the samples. One hundred and ten samples were analysed for $\delta\sp $C, with the results ranging from $-$1.49 to 5.5$\perthous$ (VPDB). The carbon isotope trend through the Lower Devonian is characterized by a flat slope within ${\pm}1.5\perthous$ of the mean value. One hundred and ten samples were analysed for $\delta\sp $O, with results that ranged from $-$8.84 to ${-}1.89\perthous$ (VPDB). The oxygen isotope trend through the lower Devonian is flat, except for the New York State samples which fall ${\sim}2\perthous$ lighter, probably because of the ambient temperature of the coeval seawater. For $\sp‡$Sr/$\sp†$Sr, the new data set is continuous and consistent for all study areas and shows a decrease from 0.70882 to 0.70782 from the Pridoli to the Emsian/Eifelian boundary. The Lower Devonian trend also fits well with the previously published Middle Devonian data. In detail, a relatively stable $\sp‡$Sr/$\sp†$Sr ratio for the Lochkovian is followed by a rapid decrease through the Pragian, and by a period of short-term small oscillations $(2\times 10\sp{-4})$ in the Emsian and the Eifelian. The observed decline in $\sp‡$Sr throughout the Lower Devonian may suggest that the fraction of strontium derived from seawater/mantle interactions is on the increase through the Lower Devonian in relation to strontium derived from sialic sources such as weathering of the continents. Paleogeographic and biogeographic data for this time period suggest that the relative sea level in the Lower Devonian was rising, possibly due to increased spreading rates at MOR's, in accord with the observed strontium isotope trend. In terms of stratigraphic resolution, the slope of the $\sp‡$Sr/$\sp†$Sr curve for the Lochkovian is too flat to be of utility for correlation purposes. In contrast, the steep slope observed in the Pragian and steep short-term fluctuations found in the Emsian may provide stratigraphic resolution on the order of 1-2 Ma.

The Modum complex within the Kongsberg sector of southern Norway is dominated by Early- to Mid-Proterozoic quartz-rich metasedimentary rocks that have been metamorphosed to sillimanite grade during the Kongsbergian orogeny (ca. 1500 Ma). At the onset of the Sveconorwegian (Grenvillian) metamorphism, multiple gabbroic units were emplaced at mid-crustal levels (less than 8 kbar) along north-south deformation zones. Alteration of the metagabbros to amphibolite was nonisochemical, with increases in the concentration of Na, Fe, P and high field strength elements (HFSE) (i.e. Ti, rare earth elements (REE), U, Th, Nb), and decreases in the concentration of Al, Mg, and Ca. The consistent and significant increase in HFSE is not observed in other studies of amphibolitization from southwest Scandinavia. The HFSE were either mobile and enriched or alteration to amphibolite was accompanied by a loss of mass in the order of 60%. Hornblende and scapolite in metagabbros and amphibolites contain very high concentrations of Cl (ranging from 0.76 to 2.03 wt. % and 2.85 to 3.34 wt. % for the respective minerals). Unlike the amphibolites, amphiboles or biotite in the albitized rocks do not contain abundant Cl, which may be a result of the ionized character of Cl in fluids at greenschist grade temperatures. Albitites display relative increases in the concentration of major elements Na and Si and decreases in Mg, Fe and Ca. The trace element concentrations are similar to amphibolites, with the exception of Sr and Cl, which occur at lower concentrations in the albitites. North-south trending bands of disseminated Fe-sulphides, in the order of ten metres wide, occur within the quartz-rich metasedimentary rocks of the Kongsberg sector; historically known as fahlbands. Chemical similarities between the amphibolite and the albitized rocks suggest that one evolving fluid may be responsible for both. (Abstract shortened by UMI.)

A recent theory implicated redox-gradients in vertical transport of elements from buried mineral deposits to surface soils and predicted the formation of 'reduced chimneys' in intervening overburden. This thesis tests that theory through surface and/or subsurface investigations at six sites; two host electronically conductive sulphide mineralization and four host non-conductive chemically reduced features including three kimberlites and an H2S-sourced 'forest ring.' Redox and spontaneous potential (SP) measurement techniques were developed and surveys carried out on surface and down-hole. Methods included: oxidation-reduction potential on groundwater and soil slurries; determination of H2S(aq)/SO42-(aq) in groundwater and O2(g) and CH4(g) in the headspace of wells; and a hybrid redox-SP method using both Pt and non-polarizable electrodes. The predicted 'reduced chimneys' were observed in overburden above mineralization. SP measurements demonstrate the presence of negative electrical anomalies over buried electronic conductors but positive responses over the non-conductors. It is proposed that strong redox gradients induce an electrical field, which results in mass transport of ions. Redox-active chemical species in a redox gradient are influenced by neighbouring species that are more electronegative on one side than the other. Redox-active polar ions and molecules should therefore exhibit a preferred orientation with their negative poles pointing in the positive redox direction, i.e. toward the neighbours with the strongest affinity for electrons. Alignment of constituent dipoles would result in a macroscopic polarity within the redox gradient and electrical anomalies that are negative at its oxidizing end. Since resistivity is finite, this electrical field should induce current in the form of an ion flux. The theory accounts for geochemical and electrical anomalies over buried mineralization in a variety of environments. It suggests that a negative SP response should develop above a buried, reduced feature if a redox gradient above it is positive-upward. However, where a reduced chimney extends to surface, the predominant redox gradient is horizontal and oxidizing-outward, which would induce a positive-inward electrical polarity and a positive SP response on surface above the feature. Buried electronic conductors are a special case in which the whole conductor polarizes in the positive-upward redox gradient of the shallow Earth's crust.

The main objectives of the present study were to first determine the chemical and mineralogical composition of bacteriogenic iron oxides (BIOS) collected from various locations (i.e., wetlands near Deep River, Ontario, hydrothermal sea vents along the Kermadec Arc between New-Zealand and Fiji, and from the Aspo tunnel in Sweden), to assess their sorptive capacity for Sr and to measure their rates of reduction in the presence of a well known iron-reducing bacterium. X-ray diffraction (XRD) and selected area electron diffraction indicated that both marine and freshwater BIOS were composed of the iron mineral, 2-line ferrihydrite, in combination with cellular structures of known iron-oxidizing microbes such as Gallionella spp., Leptothrix spp., and Mariprofundus spp. Mossbauer spectroscopy of marine BIOS confirmed 2-line ferrihydrite as the dominant mineral phase, but a small fraction of more crystalline oxides may also have been present (as detected by XRD). Using electron microscopy, the mineral phases were typically observed as 100-200 nm thick crusts of poorly structured material, attached to the surfaces of the associated microbial debris. Some well-defined crystal habits were observed in one marine sample. Sorption experiments showed that BIOS were effective adsorbents of dissolved strontium. Sorption isotherms indicated that Sr was bound to the BIOS via reversible outer-sphere complexation. Extended X-ray absorption fine structure (EXAFS) confirmed binding of hydrated Sr2+ but failed to elucidate whether sorption occurred to sites specific to the iron or organic component of the BIOS. All BIOS samples were more susceptible to microbial Fe(III) reduction than was synthetic 2-line ferrihydrite. This suggests that BIOS are not stabilized by precipitation along microbial surfaces, and that the use of synthetic analogs to model BIOS reactivity is insufficient. Reduction of BIOS resulted in the complete dissolution of the iron mineral phase, and a nearly complete solubilization of the sorbed Sr. This suggests that sorption occurs primarily to sites within the iron oxide component. In a natural BIOS deposit, levels of dissolved Sr in BIOS porewaters were elevated at depths where Fe(II) was also elevated, and levels of dissolved Sr were 2 to 3 times higher in aquifer waters that did not contain BIOS. These data suggest that BIOS may represent a natural means of Sr attenuation, provided oxidizing conditions are maintained.

<p> The study of the interaction between matter and electromagnetic radiation which procreated the wide branch named as Spectroscopy has gained tremendous attention since the last century. Atoms and molecules respond to electromagnetic radiation to produce their unique spectra which can be used to detect, identify and quantify valuable information about the substance under study. Since, its conception, spectroscopy has been widely used in physical and analytical chemistry and has ramified various techniques depending on the different types of radiation. This dissertation focuses on implementation of various spectroscopic techniques such as Infrared, Raman and Nuclear Magnetic Resonance (NMR) spectroscopy in order to determine theoretical, conformational, qualitative and quantitative properties of different molecules under study. </p><p> Understanding the physical structure of a molecule is fundamental for function, dynamic, and mechanism studies. Infrared and Raman spectroscopy are two of the most widely used and powerful techniques for the accurate determination of molecular symmetry and conformational stability. They provide information of molecular vibrations and the two techniques complement each other to yield more complete information about the molecular structure than when they are evaluated separately. One of the focus of this dissertation is the determination of the structural parameters, conformational stability, vibrational assignments and <i>ab initio</i> calculations of organic molecules containing five membered ring and phosphorous by utilizing infrared and Raman spectral techniques. The findings of my spectroscopic, structural, and theoretical studies are based on infrared and/or Raman spectra of gas, liquid, solid as well as variable temperature xenon solutions, and microwave spectrum which are supported by <i>ab initio</i> and DFT calculations.</p><p> Nearly four decades ago the potential of Nuclear Magnetic Resonance (NMR) spectroscopy for the quantitative analysis of organic chemicals was first demonstrated. Along with solution state NMR, for past two decades solid state NMR spectroscopy has also come to the forefront of quantitative analytical techniques in pharmaceutical research, as, both of these techniques have been successfully applied to the study of polymorphism in pharmaceutical drugs at both the qualitative and quantitative levels. The investigation of our research presented in this dissertation was initiated by selecting AIDS, the predominant pandemic of twenty-first century and Tenofovir (TFV), a well-tested antiretroviral drug that has proven its mettle against HIV/AIDS. In order to be able to accurately quantify the amount of drug being delivered in human body is a crucial requirement of any drug development process. We specifically focused on phosphorous containing drugs and hence, a part of this dissertation describes about the development and implementation of a general ³¹P qNMR method to achieve direct, real time quantification of <i> in vitro</i> drug release. We have effectively utilized both solution state and solid state ³¹P qNMR spectroscopic techniques to establish the kinetics of drug release and to determine the encapsulation efficiency of nano-formulation for a particular drug under study, respectively. The <i>in vitro</i> drug release profile has been studied in various human body fluids such as simulated vaginal &amp; seminal fluids, plasma etc. depending on the drug under study. The results of method validation parameters for TFV in simulated vaginal &amp; seminal fluid and human plasma obtained by using ³¹P solution state qNMR spectroscopy are presented in this dissertation.</p><p> Another chapter of this dissertation explains the analysis of calcined clay as supplementary cementitious material, obtained from Ghana, a West African nation, which does not have an abundance of commonly used SCMs such as fly ash, silica fume, metakaolin, and slag. However, the abundance of clay minerals in the country could provide a sustainable alternative with respect to SCMs application. Qualitative techniques such as Thermal Gravimetric Analysis (TGA) and Forrier Transform Infrared Spectroscopy (FTIR), and quantitative tools like Nuclear Magnetic Resonance (NMR) are able to provide meaningful characterizing of thermally activated clays. In this study, clay from Ghana was thermally activated at temperatures of 600, 700, 800, 900 and 1000&deg;C. The main objective was to characterize calcined clay using TGA, FTIR, NMR, and their relation to pozzolanic activity to best understand the potential of this abundant resource to alleviate cement supply burdens.</p>

The geochemistry of 203 fresh, glassy, zero-age basalts dredged from along the 500 km long Juan de Fuca Ridge (JDFR) illustrates the unique and complex behavior of this active spreading center located on the northern end of the East Pacific Rise. The Cobb-Eickelberg Seamount chain, the trace of the Cobb hot spot, intersects the JDFR at 46(DEGREES)N, where a young, volcanically active seamount, astride the ridge, gives clear evidence for continuing hot spot activity. In contrast with other well-documented mantle plume - ridge intersections (eg. Iceland, Azores, Galapagos), there are no systematic geochemical gradients away from the center of maximum volcanism. Petrographic and major element evidence indicates that most JDFR basalts are normal 'depleted' mid-ocean ridge basalts (MORB). However, unlike the vast majority of MORB, the trace element ratios along the JDFR, although highly variable on the scale of single dredge hauls, are predominantly transitional (Zr/Nb = 22) between depleted MORB (Zr/Nb greater than 40) and enriched oceanic island (or plume) basalts (Zr/Nb = 10). North of the Cobb Fracture Zone at 48(DEGREES)N, the Endeavour segment is chemically distinct from the rest of the JDFR with uniformly enriched trace and rare earth element ratios (Zr/Nb 7-15, La/Sm(, ch ) greater than 1). Geochemical variability observed along the JDFR requires a heterogeneous mantle source for JDFR basalts. Transitional trace element ratios can be explained by regionally extensive mixing of enriched (Endeavour-like) and more normal MORB magmas, however, this mixing is not simple, two component mixing. Highly evolved basalts, (Fe(,2)O(,3)* greater than 12.0 wt.%, TiO(,2) greater than 2.0 wt.%) resulting from extensive crystal fractionation requires this mixing be sporadic.

The Du Toitspan kimberlite pipe located on the outskirts of Kimberley South Africa, is one four Cretaceous aged major kimberlite pipes from the well-known Kimberley cluster, the type locality for archetypal group I kimberlites. Twenty-seven samples representative of various kimberlite intrusions from the eastern lobe of the Du Toitspan kimberlite pipe have been analysed for their whole-rock geochemistry and mineral chemistry (olivine and phlogopite) with the aim of developing semi-quantitative models that constrain their petrogenesis and characterise their respective source region(s). Investigated intrusions include; D13-phlogopite kimberlite, D14-monticellite kimberlite, D17-serpentinized phlogopite kimberlite, and several narrow (<1m) calcite kimberlite dykes ranging in texture from aphanitic to macrocrystic. The aphanitic calcite dykes were further sub-divided into; a phlogopite-rich calcite kimberlite, a perovskite-rich calcite kimberlite, opaque-rich calcite kimberlites and serpentine calcit e kimberlites.

Includes bibliographical references. / Karoo volcanics of Jurassic to Cretaceous age crop out in the eastern areas of southern Africa. These volcanics are well preserved in the Lebombo monocline which straddles the borders of South Africa, Swaziland and Mozambique, and in the Nuanetsi and Tuli synclines and Sabi monocline of south-east Zimbabwe. Geochronological and geochemical data have been used to evaluate the geochemistry of the rock types found in the above areas, particularly with respect to the mafic volcanics of the Lebombo. In the eastwardly dipping Lebombo monocline, nephelinites overlain by picrite basalts occur in the northern part of the volcanic succession whereas over the remaining area olivine-poor basalts are dominant. Rhyolitic volcanics in the form of massive flows overlie the basaltic rocks and attain their maximum thickness in Swaziland and the southern Lebombo. The rhyolites are notably thinner to the north of Swaziland and are overlain by an upper sequence of olivine-poor lavas with interdigitated rhyolite flows. Basic dykes are ubiquitous in the Lebombo whereas acid dykes, though present, tend to be localised. In Nuanetsi, picrite basalts, olivine-poor basalts and rhyolite flows with interbedded basic lavas crop out ina major synclinal structure. Dyke rocks are common and late Karoo intrusive complexes cut the lavas. Volcanic rocks in the Tuli syncline consist predominantly of picrite basalts and olivine poor lavas, whereas nephelinites, picrite basalts and olivine-poor lavas crop out in the Sabi Monocline.

The Precambrian Otavi dolomites in the district of Tsumeb in Namibia are host to base metal mineralization but large tracts of these rocks occupy a mature pediplain and are deeply buried by transported overburden of Kalahari age. This sandy material makes exploration for minerals very difficult. Hydrogeochemistry was considered as a possible answer to the problem of prospecting in this region but a major obstacle was the lack of an undisturbed site for orientation studies. The Tsumeb mine was therefore used as a "surrogate" orientation target and water samples collected there were analyzed for about forty elements or ions. The data were plotted on long-sections through the orebody and examined with the aid of simple statistical calculations. The Na/Cl⁻ ratio proved to be a powerful index for identifying groups of waters with a common origin. It appeared that the most important of these groups of waters were not natural groundwaters but were being recycled. Millions of litres of water are pumped from the mine daily and a significant proportion finds its way back into the workings through seepage. This conclusion was supported by chemical data and by calculations in which the rates of pumping and recharge were balanced. Over the years the process of recycling has caused a rise in the concentrations of sodium, chloride and sulphate in the water arriving at the sumps in the mine. The other major components of these waters - Ca, Mg and HCO₃⁻ - are not affected to the same extent by recycling because of controls imposed by the carbonic system. It was not generally possible to establish rational links between the distributions of the trace elements, the major groups of related waters and the proximity of ore. Although some trace elements tended to be more abundant in samples from the upper parts of the mine, where exposure to broken, weathered ore is greatest, the value of this association was diminished by the fact that these waters are recycled effluents that cannot be equated with the natural groundwaters that would be in contact with any undiscovered ore-bodies similar to the Tsumeb lode. This conclusion was reinforced by the fact that some of the trace elements were relatively abundant in waters that were comparatively saline but which had not been exposed to oxidized ore. It was concluded that it would not be possible to interpret the trace element data from the mine waters unambiguously. Nevertheless it was clear that sulphate, Cu, Pb, Zn, Hg, Cd, Se, Te and perhaps U were being mobilized from the ore and that these were therefore all good "candidate'' pathfinders. Less probable candidates were Mo, Ge, As, Na and chloride. A second orientation study was then undertaken, using normal groundwaters from boreholes and springs on surface. Sampling was concentrated around the Tsumeb and Kombat mines as targets and waters were also obtained from background areas where dolomites were exposed. The chemical data were plotted on maps by computer and were examined with the aid of simple statistical calculations such as the cumulative frequency distribution. Although anthropogenic effects were apparent at both mines they were not severe and it was possible to be more confident about the prospective roles of the various chemical species in hydrogeochemical exploration for ores in the Otavi dolomites. These prospective roles may be summarized as follows: undetectable or of virtually no interest: pH, temperature, phosphate, K, Ti, Fe, li, Rb, Cs, V, Cr, Mo, Ag, Au, Cd, Hg, Tl, Ge, As, Sb, Bi, Se and Te; useful as iridicators of regional hydrogeochemical features not directly related to mineralization: Si, F⁻, Sr and Al; weak regional pathfinders: Ni and Co; probably good regional pathfinders: sulphate, Cu, Pb and Zn. Bicarbonate, Cl⁻, Na, Ca and Mg are not pathfinders but it is useful to have these data when considering the nature and significance of the samples and the abundances in them of the trace elements. Despite the identification of a suite of pathfinders it was not feasible to establish orientation criteria such as contrast ratios. An attempt was made to apply the findings of this orientation survey in an area to the northeast of Tsumeb, where dolomites are buried under thick sand and calcrete. An area of five thousand square kilometres was selected and all usable sources of groundwater within it were sampled. The following data were collected: total dissolved solids, pH, Ca, Mg, Na, bicarbonated chloride, sulphate, Cu, Pb and Zn. Hydrological data suggested that the regional movement of groundwater was from the exposed dolomites into the pediplain. The hydrogeochemical data showed that during this migration the major element composition of the groundwater changed ("metamorphosed") radically. Because of this metamorphism, very severe difficulties stood in the way of applying in the sandy pediplain what had been learned in the areas of well-exposed dolomite. An attempt was therefore made to provide tighter control between the lithology of the geological profile and the hydrogeochemistry of the associated formational waters in the pediplain. This work consisted of (a) a sampling program to try to ''fingerprint" specific formational waters. This proved to be impossible. (b) drilling four diamond drill holes near selected anomalies and studying the cores in detail. These revealed that the Kalahari beds were very thick (46 to &gt;103m). In all cases the base of the overburden was far below the present water table and in some cases the overburden was underlain by unmineralized rocks other than dolomite. These results indicated that the hydrogeochemical anomalies were probably spurious and it was concluded that hydrogeochemical exploration in this kind of Kalahari terrane was not practicable.