Spelling suggestions: "subject:"mineral resources"" "subject:"ineral resources""
221 |
Geological setting of the volcanic-hosted Silbak Premier Mine, northwestern British Columbia, (104 A/4, B/1)Brown, Derek Anthony January 1987 (has links)
Detailed mapping of a 7.5 km² area at 1: 2,500 and a 1:10,000 compilation map over 60 km² have established Hazelton Group stratigraphy and structure. Hazelton Group stratigraphy begins with at least 1,000 metres of Late Triassic-Early Jurassic (210 ⁺²⁴₋₁₄ Ma; U-Pb zircon) green andesite flows, breccias
and tuffs. Less than 1750 metres of green and maroon andesitic to dacitic volcaniclastic rocks overlie the andesite unit. North of Silbak Premier, at Slate Mountain, the volcaniclastic unit is overlain by up to 200 metres of a black tuff unit containing characteristic fresh biotite and white plagioclase fragments. The top of the Hazelton is a regional marker horizon, the Monitor rhyolite breccia and tuff (197 ± 14 Ma; zircon U-Pb). Hazelton volcanics are overlain by three different units. At Slate Mountain the Bowser Lake Group Bathonian/Callovian argillite and siltstone (at least 1500 m thick) lie above Hazelton rocks. Farther north on Mount Dilworth, Monitor rhyolite is succeded by black tuff or a Toarcian buff carbonate. East of Monitor Lake, less than 75 metres of Bajocian Spatsizi Group silicic shale and tuff overlies Hazelton volcanic rocks.
Three intrusive episodes are discerned through isotopic dating: Early Jurassic (190 ± 2 Ma; U-Pb zircon) Texas Creek plutonic suite dacitic porphyries; Eocene Hyder suite leucocratic dykes; and oligocene-Miocene (25.2 ± 2.3 Ma; K-Ar biotite and 18 ± 6 Ma; Rb-Sr) biotite lamprophyre dykes. The Jurassic suite includes K-feldspar megacrystic "Premier porphyry" sills and dykes that are in part spatially and possibly genetically associated with mineralization.
Structural features include disharmonic tight folds, ductile shear zones, and brittle faults. At least 4 phases of pre-Eocene deformation are defined by: (1) moderate west-plunging recumbent folds, (2) north-plunging inclined folds, (3) north-plunging upright folds, and (4) moderate west-plunging pencil lineations. The map area is divisible into three structural domains: the North, East and Silbak domains. The North domain is characterized by a marked structural discordance between warped Hazelton volcanic rocks and disharmonically folded Bowser Lake Group argillite and siltstone. Three phases of folding are: first phase tight to isoclinal disharmonic, recumbent folds; second phase open folds with shallow northwest-dipping axial planar cleavage; and a third phase upright, shallow north-plunging synclinorium. Structural continuity is difficult to establish due to lack of marker horizons and inferred detachments. The East domain is characterized by phase 3 gently north-northwest-plunging folds and locally east-verging asymmetric chevron folds in the Spatsizi Group. In contrast to North domain, Monitor rhyolite and/or Spatsizi Group are structurally conformable with Bowser Lake Group rxks. The Silbak domain is characterized by phase 4 pencil lineations and quartz veins. Stope geometry illustrates that mineralization occurs along two trends (1) northeast zone and (2) northwest zone of unknown phase.
Steeply dipping, east-striking ductile fabrics occur in the Texas Creek batholith at the Riverside mine, Alaska and in maroon volcaniclastics along Bear River Ridge. Mylonitic fabrics at Riverside mine suggest a dextral sense of shear. A biotite lineation in the mylonitic foliation yields a totally reset Eocene K-Ar date.
The width of Eocene Hyder dyke swarms indicates that there has been at least one kilometre of northeast brittle crustal extension. About 1400 metres of dextral transcurrent movement along the Long Lake-Fish Creek fault is post-Eocene dyke emplacement. oligocene-Miocene lamprophyre dykes fill fractures produced during east-west extension.
Regional syntectonic greenschist grade metamorphism produced a carbonate-chlorite-sericite-pyrite mineral assemblage, probably in Middle Cretaceous time, bracketed by isotopic dating results.
Hazelton Group volcanic rocks and coeval Texas Creek porphyritic rocks are subalkaline high-K to very high-K andesites and dacites. Tectonic discrimination diagrams indicate a calcalkaline, volcanic arc setting, with similar geochemical patterns to those for Andean volcanic rocks. Mineralization is hosted in Hazelton Group andesites and coeval Texas Creek porphyritic dacite sills and dykes. Mineralization and porphyry emplacement appear to have been controlled by northeast- and northwest-striking structures. Ore is predominantly discordant but locally concordant with moderately northwest-dipping andesite flows and breccias. No mineralization occurs in or above overlying maroon volcaniclastic rocks. Sericite alteration gives a Paleocene K-Ar date (63 ± 5 Ma); this is interpreted to be partially reset. The spatial link with Texas Creek K-feldspar porphyry and discordant nature of the ore suggests mineralization is Early Jurassic age and supports an epigenetic model. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
|
222 |
Geology and genesis of the Mount Skukum tertiary epithermal gold-silver vein deposit, southwestern Yukon Territory (NTS 105D SW)McDonald, Bruce Walter Robert January 1987 (has links)
The Tertiary Mt. Skukum gold - silver epithermal vein deposit occurs 65 km southwest of Whitehorse in the Yukon Territory. Veins are hosted by a sequence of nearly flat-lying Eocene Skukum Group andesitic volcanic rocks of the Mt. Skukum Volcanic Complex, part of the Sloko Volcanic Province which unconformably overlies these intrusive complexes as well as metamorphic rocks of the Yukon Group.
Major known mineralized zones occur within a regional halo of propylitic alteration centered on a fault-bounded graben within Main Cirque in the southwestern corner of the Mt. Skukum Volcanic Complex. Each zone consists of steeply-dipping quartz-carbonate-sericite veins associated with major faults and rhyolite dykes which bound blocks of the graben.
Precious metals occur as electrum and native silver as fine grains averaging 15 to 20 microns and locaIly exceeding 1 mm across, in veins containing only trace amounts of sulphides. Fluid inclusions indicate that vein minerals were deposited from hydrothermal fluids averaging 313°C with an average salinity of 0.7 weight percent NaCl equivalent. Primary inclusions show that depositional fluids existed under two pressure regimes; one close to hydrostatic, the other approaching lithostatic. Both reflect depths of deposition of about 470 m below paleosurface. Variable fluid pressures reflecting similar depths of deposition combined with variable liquid to vapour ratios in primary inclusions as well as abundant textural evidence of hydrothermal brecciation indicate that boiling was common during mineralization.
Oxygen and carbon isotope composition of minerals in the deposit and surrounding wall rocks indicate that depositional fluids were meteoric in origin with no contribution from magmatic sources. Large depletions in 0¹⁸ content of andesitic rocks in the deposit area indicate a minimum water rock ratio over the life of the deposit of 0.81:1. Precious metals at the Mt. Skukum deposit were emplaced at relatively low temperature in a near surface environment by a circulating, meteoric water dominated, hydrothermal system driven by a heat source associated with the rhyolite dykes. Gold, leached from andesitic volcanic rocks and metamorphic and granitic rocks was precipitated with quartz and carbonate in permeable conduits such as fault zones, and breccia bodies. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
|
223 |
Zdanění těžby nerostných surovin / Taxation of mineral resources extractionMedunová, Lucie January 2013 (has links)
The aim of this thesis is to compare the approaches of the taxation of the mineral resources in chosen developing and developed countries and to introduce different ways of mineral resources taxation used in the world. The thesis mainly deals with taxation of an extraction of petroleum, which is one of the most important resources. Selected countries are Nigeria and Angola, which are the largest petroleum producers in Africa from at the forefront of world rankings, followed by Russia, which is currently the largest petroleum producer in the world and finally the United Kingdom and Norway which are among the largest producers of petroleum within Europe.The first chapter of this thesis deals with the characterization of minerals. The second chapter shows the ways and specifics of their taxation. In the third part there are the characteristics of developing and developed countries and the differences in their economies and ways of taxation. There are also provided basic information about the selected states. The ways of the taxation of mineral resources in five selected countries and their comparison are presented in the last chapter.
|
224 |
Form and the picturing of mining : an epistemology of form with special reference to the explication of iconographyPayne, Malcolm January 1992 (has links)
Bibliography: pages 67-72. / The work presented here is a bounded excerpt of a broader programme of creative endeavour. Framed by the constraints of the MFA degree , the special value of this project has been the opportunity it has presented to articulate some of the ideas that have developed over a period of time and have informed my working process. The theme of mining and related activities forms the visible field in which I have extended my formal pictorial methodology . The visual primacy and corporeality of form in painting have been the enabling vehicles assisting me to re - code selected iconography. The genealogy of this form and its development is chronologically traced in three groups of work preceding the body of work executed for the MFA.
|
225 |
A study of the relationship between mineral commodity prices and exchange traded mining stock pricesNangolo, Charlotte 13 February 2012 (has links)
Investors consider commodity prices to be one of the major criteria critical in the selection of stocks of mining companies. This is done as part of the net present value (NPV) valuation of mining companies. It is believed that one of the three sets of mineral commodities prices, which are: spot price, forward price and long term price, has a greater impact on the share valuation processes used by investors. This research study investigated the extent to which each set of commodity prices influences the valuation process in order to provide investors of mining stocks with a greater understanding of how fluctuations of commodity prices over time affect prices of the mining stocks they hold, intend to sell or buy.
A literature review conducted identified different valuation methods employed in valuing share prices. The literature study also revealed price cycles experienced in the commodity sector. Emerging from the literature review was the prominent role of commodity prices in valuing stocks of mining companies. Three mineral commodities namely, gold, silver and copper were used as case studies because stock market data on these commodities is readily available in the public domain. Nine market indices covering all three mineral commodities were selected based on defined criteria that ruled out any ambiguity and tested for correlation with the three sets of mineral commodity prices. An equal number of stocks of individual mining companies, which were not the primary drivers of the indices, were used to validate the results obtained from the indices in order to avoid duplication of the same correlation during cross – checking. Each mineral commodity price was adjusted for operating costs. For market indices, an average operating cost for each index was calculated from the companies in its basket, while for stocks of individual companies, the company’s annual operating costs were used. The data was collected for the period January 2004 to October 2010. This period was further split up into three sub – periods to account for the Global Financial Crisis (GFC) period that started in mid – 2008.
This research study concluded that mining stock prices are correlated with mineral commodity prices, but with spot and forward prices exhibiting stronger correlations than long – term price. This finding is useful to mineral stock evaluators and any evaluator of a mineral asset in that where cash flow approach methods are to be used and the commodity price is required to estimate future cash flows, spot price forecasts of that mineral commodity should be used and not the long – term price.
|
226 |
Mining, dependence, and post-independence urbanisation in Botswana : sustainable development?Haynes, Michael J January 1990 (has links)
Bibliography: leaves 187-197. / Botswana has been considered as one of the few post-independence development successes in Africa. The country's recent status is attributable to the growth of the minerals sector, with diamonds and copper/nickel matte forming the basis of exports and government development revenues. Mining has not only been responsible for boosting export earnings, but has also stimulated most recent urbanisation, resulting in the some of the highest urban growth rates in sub-Saharan Africa. The problem of urban in-migration has been compounded by a bias in development expenditure, with the towns receiving a disproportionately large share of scarce resources. All new towns since independence have been established as service centres for the mines, with limited wider development occurring. Resultant vulnerability and instability in the urban sphere has been reflected in the case of Selebi-Phikwe, where a decline in the copper/nickel industry has threatened the future integrity of the town. That mining has not contributed towards development which is sustainable over the long terms calls into question, the resilience of Botswana's progress. A political-economic analysis of the development history of Botswana indicates a continuity between colonial neglect and the migrant labour system, and the current problems of dependence on the mining sector and external employment opportunities. The reasons for the dearth in diversified productive activity in mining towns in Botswana are related to an externally orientated development policy, with dependence on the world mineral markets. As the mining industry is based on the extraction of finite, non-renewable resources and is susceptible to fluctuations in mineral pricing, towns exclusively based on mining are latently unstable and have similarly finite lives. The problem is compounded by the lack of a local entrepreneurial class capable of stimulating the 'modern' sector which is related to the historical lack of an urban elite in the country. Given that there has been minimal associated development of productive opportunities outside of the primary sector in Selebi-Phikwe, the Government has instituted a crisis management strategy to deal with the situation. Proposals to diversify the economic base of Selebi-Phikwe are focused on attracting foreign investment, as a means of stimulating local, export-orientated industrialisation. As the incentives for locating in the town are primarily based on cheap, malleable, labour supplies, transnational investment is likely to be of a highly mobile nature and is unlikely to sustain employment and development in Selebi-Phikwe Certain conclusions are drawn from the experience of Selebi-Phikwe: Firstly, the problem of continuity in Selebi-Phikwe has historical roots indicating that short term panaceas are unlikely and that structural solutions are needed. Secondly, the town's fate holds important implications for the maintenance and support of the wider urban system in Botswana. Thirdly, expectations of indefinite economic prosperity have been generated in part, by continual Government emphasis on urban infrastructural development, something which is potentially problematic given the potential for urban discontinuity. A more rational evaluation of the urban sector in Botswana is required. With the precarious foundations of urbanisation in Botswana borne in mind, surplus revenues generated by mining should be channelled into rural employment creation rather than urban areas. An approach which treats the urban question in its entirety is required. There is thus a real need for a national development programme which integrates population and environmental policy with rural and urban sector planning, and which bases future development on the criteria of equity and sustainability.
|
227 |
El Serafy User costs and their implications for macroeconomic policy in Africa's mineral rich economiesMoussi, Sopp Louis Romain 22 February 2019 (has links)
Many of Africa’s economies are mineral based. Their sustainability and their macroeconomic vulnerability to market fluctuations are accordingly matters of direct concern. This thesis asks how much of the proceeds of mining in such countries can be safely spent each year. Using El Serafy’s approach to the ‘proper’ definition of National Income, it recomputes Net Domestic Product in 11 mineral-based African economies and tests for their macroeconomic sustainability. The study finds a disturbingly poor level of sustainability in several of them; with aggregate expenditures in excess of the levels posited under efficient resource rent management given the El Serafy User cost approach. The study estimates the budget deficit and national debt as a proportion of net national product adjusted for mineral resource depletion in each country and evaluates the outcome by comparison with standard ‘rules of thumb’ concerning ‘acceptable’ fiscal deficits and national debt levels. The outcome reveals that using GDP as an anchor as opposed to an ‘appropriate’ measure that adjust for mineral resource depletion by policy-makers may lead to the implementation of sub-optimal economic policies which are detrimental for sustainable income growth and development. The findings from the study therefore highlight the need for more efficient resource management as well as the development of a ’properly defined‘ national income which corrects for resource depletion to inform sustainable fiscal policy.
|
228 |
The Mineral Resources of the Sevier River Drainage, Central UtahSanders, David T. 01 May 1962 (has links)
A survey of the mineral resources, the economic rock products, and the ground-water reserves of that part of central Utah drained by the Sevier River system was undertaken by the author in the fall of 1960 as a continuation of a research project directed toward the stiumulation of economic growth in the state of Utah. The project was initiated in 1959 by Dr. Donald R. Olsen and Dr. J. Stewart Williams, who conducted a similar survey of a five county area in southwestern Utah (Olsen and Williams, 1960).
Through a review of existing literature, preliminary field examination of most of the important areas, and communications with owners, operators, and consulting geologists, an attempt has been made to include in this survey all of the important economic mineral and rock deposits. A review of the ground-water supplies of the region and a discussion of related problems are also included.
Each of the minerals and rock products is described alphabetically in a brief statement. This statement includes information concerning location, present status, present ownership, and geologic controls of accumulation. Where possible an estimate of the economic potential of each commodity is made. These estimates are based on accessibility, tonnage, grade, market value, etc. Each occurrence is also located on a map of the area.
|
229 |
The impact of mineral resource rent tax on the financial performance of mining companies in South AfricaMathivha, Mukondeleli January 2017 (has links)
Thesis (M.M. (Finance & Investment)--University of the Witwatersrand, Faculty of Commerce, Law and Management, Wits Business School, 2017 / This study assesses the impact of a change in tax system in South Africa and the effects caused thereof on both the government and mining companies .This is done by comparing different tax models and analyzing the results to determine their suitability to be used in South Africa. A hypothetical case study is used to achieve the goals of the study by employing six different case scenarios under different threshold rates, tax rates and corporate income tax rates on a mining project. An NPV generated from a discounted cash flow under each scenario is used to evaluate the project success, the tax revenue generated shows how much government stands to make. The results show that the project NPV is highest when both the corporate income tax rate and the resource rent tax rate are reduced. The study also reveals reducing the tax rate has a greater effect on changing project NPV and potential government revenue than reducing the threshold rate and/or the corporate income tax rate. An assessment on the readiness of South Africa to changing tax systems shows that although the resource rent tax system can generate high revenues for government, the disadvantages of changing tax systems on the country as a whole currently outweigh the advantages / MT2017
|
230 |
Mineral resource potential : Rouyn-Noranda region, QuebecUmar, Pervez Akhtar. January 1978 (has links)
No description available.
|
Page generated in 0.059 seconds