Spelling suggestions: "subject:"mineral resources"" "subject:"ineral resources""
211 |
The South Wales miners, 1964-1985Curtis, Ben January 2007 (has links)
In May 1981, at the South Wales Area NUM annual conference, Area president Emlyn Williams addressed the delegates and told them that the south Wales miners 'are associated in people's minds with resistance and struggles ... There is no doubt in my mind that miners have an historical mission to lead in class struggles'.1 This statement expressed the conscious self-image of the South Wales Area and was also a reaffirmation of an important historical trend. During the twentieth century the miners were generally considered to be amongst the most militant sections of the British labour movement, with South Wales very much in the forefront of this. This thesis examines both how and why the south Wales miners held this prominent 'vanguard' role. My research explores the history of the south Wales miners between 1964 and 1985, examining the interrelationship of coal, community and politics through the prism of their Union. The period covers the concerted run-down of the coal industry under the Wilson government, the growth of miners' resistance and the brief prospect of a secure future for them, through to eventual NUM defeat in 1985. In this socio- political history, the emphasis is on the dynamics of the relations between colliery lodges, the South Wales Area and the national NUM, the response of the Area to industrial and political developments, and also the impact of this upon its relationship with the wider labour movement. In many respects however, labour history is not currently 'fashionable'. The decline of the densely-unionised heavy industries, together with the global hegemony of neo-liberalism, has led many to believe that this subject is no longer relevant - even though the working class has not disappeared just because more people in Britain now work in call centres and supermarkets than in collieries or steelworks. Nevertheless, as Mcllroy and Campbell point out, '[t]he [current] debility of labour studies ... have to be related to the defeats and the consequent sense of demoralisation the labour movement has suffered from, as well as state policies and academic responses to them'.
|
212 |
The concept of grade in mineral depositsEsterhuizen, Anton G 04 April 2013 (has links)
The grade of a mineral deposit is determined by the effectiveness of a geological ore forming process, which is the result of the interaction between an ore forming mechanism and the environment in which it operates. Properties of a mineral deposit controlled by ore forming processes include the distribution, density and nature of ore minerals and gangue, and the metal content and impurities of the ore minerals. More efficient ore forming processes tend to develop in the larger mineralizing systems giving rise to richer deposits. As the geological environment within which a mineral deposit evolves becomes more complex a greater number of variables interact to determine the grade of the deposit. This is reflected in the greater variability of the grade distribution, resulting in greater difficulties in obtaining reliable estimates of the recoverable grade, and increased difficulties in the processing of ores. In response to economic fluctuations the working grade of heterogeneous orebodies, that form in geologically complex environments, can often be altered to ensure the continued viability of a mining venture. In contrast the evenly mineralized orebodies that tend to develop in geologically simple environments do not have this flexibility. All the important decisions in the mining industry, such as feasibility studies, choice of ~ining and processing methods, selection and planning, are made on the basis of, or are related to, grade estimates. If the geological controls of grade are fully understood, then it is possible to optimize the selection of the various mining alternatives, leading to the efficient exploitation of ore deposits.
|
213 |
Mine planning - a study in developing a life of mine planVisser, Renier 24 October 2012 (has links)
M.Phil. / A research report, such as provided for Kenya Fluorspar, plays an integral part of the life of mine or project and creates a practical plan of running and developing the mine. This research report is used by the client as a practical strategic mine plan, and thus if followed as stipulated, will in the end not only pro-long the life of the mine but will achieve targeted value and tonnes for the specific plant. In many cases the smaller mining companies will attack an ore body and will as is called “pick the eyes out” of that specific ore body, thus mining just the high grade ore, make your money and get out. But if it comes to a mine that needs to pro-long the life of the mine due to community responsibility and the creation of work, then it is of essential value to do a technical strategic planning study on the ore body, creating different scenarios as to mine the ore body with emphasis on Life of the mine and in the same breath the economic viability of mining in the chosen scenario. The research report have a look at four different scenarios whereby there are certain constraints applied, and the outcome of the schedules are used to make a calculated decision on the best way of mining this specific ore body. Pit designs have been created from Whittle optimized pitshells which then have been incorporated within the schedules. It has been found that Scenarios 1 and 2 will have some years with very high waste removal, which will be above the current fleet capacity, but the required plant feed and grade would be possible from period one. Scenario 3 have proven that if fleet capacity is the main constraint then steady state of feed to the plant can only be achieved in the 7th year of production, but render no extra fleet requirements. As recommended, Scenario 4 stood to be the best if the acquisition of extra equipment is possible, and then steady state in the plant can be achieved in the 4th year with the lowest production percentage of 84% in the first year.
|
214 |
Sustainability beyond mining: transformations in systems for secondary beneficiationFerraz, Maria Fátima Freitas 02 November 2012 (has links)
Ph.D. / Definitions of sustainable development can be grouped according to their ideological orientation and economic paradigm in which they are placed: neoclassical; social and ecological modernisation of neoclassical; and radical. The view of sustainable development predominant in the mining sector aligns with the dominant neoclassical economic paradigm. It is revealed specifically through the system of metrics used, the most obvious of which is profit, shareholder value, and growth. The idea of sustainability is understood in mining as the need to respond to increasing regulation by adding two extra dimensions to the economic one – social and environmental. This is abbreviated as the triple bottom line, or weak sustainability. In the exercise of process stewardship, mines tend to follow global responsibility guidelines formulated for the sector, but product stewardship is of secondary importance. Narrow definitions of sustainability fail to take into account the biosphere as a complex adaptive system. In this study there is a discussion about an innovative collaborative sustainability model to be developed in a new industrial sector. That sector would operate beyond mining, while at the same time using mining waste residues feedstock as its inputs. The landscape in which the new sector would be located would be the current neoclassical one, but the model has been formulated as a tool to move towards a broader conception of sustainability. As a means of clarifying the fuzzy boundaries between the various entities and components of the complex adaptive system of the biosphere, for the purposes of discussion, the biosphere has been divided into seven separate schematic dimensions (after Gell-Mann, 1994: 345-366). These are ideological, institutional, economic, social, demographic, informational and technological. Six research and development projects, carried out over seven years (2002 to 2009) in a research and development group of a trans-national mining corporation, were directed by the author. These projects, in the fields of improved air quality and of minimisation of mining waste residues, formed the basis for conceptualising a new collaborative sustainability model. The projects, when placed in the context of seven dimensions of the biosphere and as examples of sustainable development, reveal themselves as falling far short of attaining sustainability goals. What a reductionist definition of sustainability used in the mining industry means is that the industry is slow at anticipating needs of communities after a mine closes, or after organisational restructuring and downsizing in the trans-national corporation has happened, or in dealing with the influx of people into the area who come to improve their economic/political opportunities. The implementation of sustainability principles in mines is directed by global protocols, directives and regulatory obligations, and is driven by the market economy.
|
215 |
Trace element pollution of soils by abandoned gold mine tailings near Potchefstroom, South AfricaAucamp, Paul-Johan 27 March 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc)--University of Pretoria, 2007. / Geology / Unrestricted
|
216 |
Geodynamics, rifting, stratiform and stratabound mineral depositsDingemans, D.R.W. 19 March 2013 (has links)
Stratiform and stratabound ore deposits commonly show a direct relationship with rifts. This association is studied by developing a geodynamic model of mantle processes and crustal responses. The geodynamics of the earth can be modelled by the process of mantle advection, which involves the episodic generation and segregation of low density mantle diapirs and their rise and subsequent interaction with the crust. The theory of mantle advection explains the genetic association between rifting, magmatism, basin development and subsequent orogeny and metamorphism. Global evolution has passed through a number of major stages of non-uniformitarian development in which each cycle was characterized by fairly uniform behaviour terminated by intense geodynamic upheaval. The relationship between geological evolution and mantle advection is examined by reviewing the major characteristics of each of the cycles, which correspond to the Archean, Early Proterozoic, Mid Proterozoic, Late Proterozoic-Palaeo2oic, and Mesozoic - Cainozoic eras. Although mentle advection has controlled crustal processes throughout time, the decrease in the thermal energy of the earth has caused >the major evolutionary changes in response to thickening and a greater rigidity of the sialic crust. Rifts are penetrative taphrogenic faults in the earths crust which act as major conduits for the transfer of magmas, from the mantle and lower crustal levels, to the upper crust and the surface. Rifts are also permeable zones for the migration of metalliferous brines, generated by magmatic differentiation. These metalliferous brines would either be exhaled at surface to form stratiform volcanogenic and volcanosedimentary ore deposits , or would interact with preferential host horizons to form stratabound ore deposits . The associat ion between rifting and stratiform and stratabound ore deposits is illustrated by examining :he tectonic setting, and st ratigraphic relationships of typical ore deposit types .
|
217 |
A geological evaluation of marine diamond placer deposits on the central Namibian inner shelf : a case study of the Hottentot Bay areaRau, Grant 03 June 2013 (has links)
This study focusses on the marine diamond placers within Exclusive Prospecting Licence 1950 and Mining Licence 103a, located northwest of the north-facing Hottentot Bay which is 60 km north of Lüderitz, along the central Namibian coastline. The thesis follows the natural geological evolution of the marine placer deposit from primary source, through alluvial and/or glacial transportation, concentration along the coastline by wave, aeolian and alluvial/sheet-wash processes and finally marine diamond placer preservation. All of these processes are reviewed as they are important in understanding of the evolution marine placer deposits. The poly-cyclic role of coastal aeolian, alluvial, and marine processes, in marine placer enrichment is shown to be particularly important in considered target identification and prioritisation. A detailed bathymetric, sonographic and seismic interpretation, is an integral part of diamond placer exploration, and was used to examine and describe surficial and sub-bottom characteristics within the study area. Marine placers are formed along palaeo-strandlines during periods of marine transgression and regression and are therefore fundamental in marine placer exploration. A detailed bathymetry map, compiled for this study, of the area between Lüderitz Bay and Clara Hill, provides the foundation for a detailed terrace level investigation. Regionally, twelve well-developed stillstand levels are identified, nine of which fall into the study area. These interpretations are compared with global eustatic as well as terrace and resource/reserve levels in the Lüderitz area and are found to correlate well. Sediment dynamic studies involve the use of accredited application software for wave refraction modelling, to determine the wave angle and orbital wave velocity at the seabed. Bedload velocities, required to move diamonds of specific sizes, can be empirically determined and therefore areas of diamond entrainment and deposition can be modelled and target features delineated and prioritised. These detailed interpretations provide a sound platform for evaluating diamond placer process models in the study area. By integrating both previously published and newly formulated ideas, a revised, holistic model for the formation of marine diamond placer deposits in central Namibian is postulated. The proposed model is tested by comparing it to the lateral distribution of presently defined resource/reserve areas in the Lüderitz area and shows a close correlation with most of these enriched deposits. Based on this model, a matrix for the delineation and prioritisation of marine placer deposits is developed and the best target features within the study area are identified. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
|
218 |
Petrogenetic study of the Guichon Creek Batholith, B.C.Westerman, Christopher John January 1970 (has links)
The Guichon Creek batholith is exposed approximately 200 miles N.E. of Vancouver, B.C. and is a zoned 'granitic' pluton of Lower Jurassic age (198±8my). The batholith consists of seven major intrusive phases. The predominant rock typo is granodiorite with lessor amounts of quartz diorite and quartz monzonite.
Study of rock and mineral compositions has revealed a gradual variation in the relative proportions of mineral phases as crystallisation of the batholith proceeded. The chemical compositions, however, of the individual mineral phases show very little change. The relative roles of assimilation and magma convection in producing compositional variations in the early phases of the batholith are discussed.
Alkali feldspars are microperthitic with bulk compositions in the range 71-86 Wt% Or and the compositions of the porthitic components approach pure end members. The potassic phases of the perthites have structural states equivalent to that of orthoclase. The plagioclase feldspars are oligoclases with low to intermediate structural states. Plagioclase from the early phases of the batholith (Hybrid and Highland Valley phases) show normal zoning whereas those from the later phases (Bethlehem and Bethsaida) show oscillatory zoning. Biotites from the major phases of the batholith have progressively lower Fe/(Fe+Mg) ratios with progressively increasing silica content of the host rocks. Plagioclase crystallized early in the older phases of the batholith whereas quartz was the early mineral to crystallize from the younger major phases.
Evidence suggests that magma convectod during crystallisation of the older phases of the batholith but that the younger phases crystallised from a stationary magma. Comparisons with experimental systems suggest that the early magma crystallised under conditions of relatively low total pressures in the order of 1 or 2 kb but that the later phases may have been subjected to total pressures in the order of 4 or 5 kb during crystallisation. This increase in total pressures was most probably due to increasing volatile pressures during crystallisation / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
|
219 |
Zdanění těžby nerostných surovin / Taxation of mineral resources extractionCísařová, Iva January 2013 (has links)
The aim of this thesis is to analyze reasons for specific taxation of the mineral resources extraction, to present what kind of taxes can be applied for such purposes and to compare them by calculating the tax liability of hypothetical company located in representative provinces of Canada. This calculation proved that when mix of taxes is applied, where part of the income is taxed by corporate income tax and on the other part of income extraction tax is levied by using royalties, the same government revenue can be reached as when linear tax rate is applied as an extraction tax. However, royalties also bring other advantages, e.g. the simplicity of administering extraction taxes or low demands in calculating the tax liability for extractive companies.
|
220 |
British Columbia parks and mines in conflict : an evaluation of resolution processesMarcy, Norman Karl January 1985 (has links)
The purpose of this thesis is to evaluate alternative processes for resolving conflicts between mineral development, and park preservation interests in British Columbia. The peculiarities and variation within the generic conflict illustrate the divergence between two main interest groups, and the representative provincial resource agencies. A brief examination of eight cases demonstrates the conflict is manifest with different intensities, over a wide time range, and with geographic variety. By comparing the supposed weakness of the litigation model and the claimed advantages of the bargaining model for processing of conflict to resolution, five criteria for efficiency are developed: time and delay; cost; capacity for technical issues; opportunity for participation; and flexibility of outcomes. Examples of conflict dialogue illustrate cognitive, value, interest and behavioral conflict in the parks / mines situation with the aim that the reader and the researcher can have a communality of experience and tools for understanding in assessing the detailed case evidence. Detailed examination of the Wells Gray Provincial Park case and Chilko Lake Wilderness Park Proposal illustrate strong British Columbia examples of both litigation and bargaining models under the same time and political circumstance. Not all of the allegations of strength or weakness are substantiated in either case. The promise demonstrated in the unstructured version of bargaining found in the Chilko example may be improved through innovation and commitment. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
|
Page generated in 0.0728 seconds