Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os minerais estão presentes no cotidiano humano sob as mais variadas formas, seja no campo da metalurgia, da indústria química, da construção civil ou do cultivo da terra. De uma maneira geral, constata-se que o caminho trilhado pelo desenvolvimento da humanidade foi e é alcançado mediante a busca e utilização de bens minerais. Dada a extensão territorial e a diversidade geológica encontrada no solo e subsolo, o Brasil apresenta como detentor de importante potencial minerário no cenário mundial. Nesse contexto, Roraima constitui-se numa região que foi tradicionalmente voltada à exploração de bens minerais, sobretudo ouro e diamante. Principal porto fluvial do estado de Roraima, muito importante em passado recente, o município de Caracaraí RR perdeu sua função axial com a construção da rodovia BR-174. O desenvolvimento de sua zona rural está baseado na pecuária, o núcleo urbano no comércio e serviços e o setor minerário ainda incipiente. Este estudo enfoca um levantamento dos recursos minerais de importância econômica, inclusive os que estão em fase de exploração no município, utilizando como meios auxiliares produtos de sensoriamento remoto e dados de campo. Foram pesquisados 19 pontos amostrais, sendo oito nas proximidades da BR-174 e 11 em bibliografias consultadas. Foram confeccionadas cartas imagens de ocorrências minerais, substâncias minerais e de mineração em atividade. Caracaraí possui áreas de potencial mineral, tais como areia, seixo, argila, granito e laterita, com ocorrências de ouro. Outros minerais têm sido descobertos na forma de pequenos depósitos ainda pouco investigados, porém as áreas destinadas às terras indígenas e conservação ambiental, conduzem à redução da exploração dos mesmos, além de criar barreiras impedindo os avanços no conhecimento geológico e nas descobertas de novas ocorrências minerais no município. / The minerals are present in everyday human under the most varied forms, whether in the field of metallurgy, chemical industry, construction or farming. In general, it appears that the path followed by the development of humanity was and is achieved by seeking and use of mineral commodities. Given the territorial extension and geological diversity found in soil and subsoil, Brazil has great potential as a holder of mining on the world stage. In this context, Roraima is in a region that has traditionally focused on the exploitation of minerals, especially gold and diamonds. Main river port in the state of Roraima, very important in the recent past, the city of Caracaraí - RR lost its axial with the construction of highway BR-174. The development of their rural area is based on farming, the urban core in trade and services and the mining industry still in its infancy. This study focuses on a survey of economically important mineral resources, including those in the exploration stage in the city, using as auxiliary products of remote sensing and field data. We surveyed 19 sampling points, eight near the BR-174 and 11 in bibliography. Images were prepared letters of mineral occurrences, mineral and mining activity. Caracaraí has areas of mineral potential, such as sand, gravel, clay, granite and laterite, with gold occurrences. Other minerals have been discovered in the form of small deposits still poorly investigated, but the areas allocated to indigenous lands and conservation, leading to reduce the exploitation of them and create barriers impeding progress in geological knowledge and discoveries of new mineral occurrences in the city.

Orientador: Alvaro Penteado Crósta / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-24T23:17:39Z (GMT). No. of bitstreams: 1 RodriguezMelo_Juanita_M.pdf: 7821554 bytes, checksum: 5ad2b10d82bc051c55f839d303453afd (MD5) Previous issue date: 2014 / Resumo: O objetivo principal deste trabalho foi avaliar o potencial prospectivo para ouro e metais associados de uma área localizada no norte do Cinturão de Maricunga, Chile. Análises por espectroscopia de reflectância foram obtidas na área do prospecto Salares Norte possibilitando o reconhecimento de assembléias de alteração hidrotermal incluindo minerais como caulinita, esmectita, alunita, ilita e minerais portadores de sílica. A presença destes minerais foi conferida por análise petrográfica e de microscópio eletrônico de varredora (MEV). A análise da distribuição espacial desses minerais foi determinada aplicando as seguintes técnicas de processamento digital a uma cena do sensor Terra/ASTER: Análise por Principais Componentes (APC), Spectral Angle Mapper (SAM) e Mixed Tuned Matched Filter (MTMF). A exatidão de cada um dos mapas foi avaliada tomando como referência os dados de espectroscopia de reflectância. O resultado indicou a APC como a técnica mais acurada para o mapeamento de minerais de alteração hidrotermal, com uma exatidão total de 44,34%. Embora este valor de exatidão seja relativamente baixo, os dados de menor acurácia encontram-se nas regiões onde não é reconhecida alteração e os de maior acurácia concentram-se nas áreas alteradas e, por conseguinte, as de maior interesse. Combinando a informação espectro-mineralógica à interpretação de dados geoquímicos (ICP-MS) e litológicos, foi possível concluir que as assembléias minerais de alteração em Salares Norte se formaram sob condições epitermais de alta sulfetação, com atual exposição, marcada por baixo nível de erosão. Os tipos de alteração identificados foram argílica (caulinita±esmectita), argílica avançada (quartzo+alunita+caulinita) e alteração com sílica no núcleo do sistema. Alteração tardia do tipo steam-heated foi reconhecida em uma ampla área, sendo que quase em toda a sua extensão se encontra sobreposta às alterações argílica avançada e silícica. As zonas de alteração exibem uma evidente tendência estrutural de direção NW-SE coincidente com a disposição de anomalias geoquímicas de Au, Ag e Hg. Por essa razão, este componente estrutural NW-SE se destaca como possível controle da alteração/mineralização em Salares Norte. Dentre as unidades litológicas identificadas no prospecto, uma brecha freato-magmática destaca-se como provável portadora/concentradora da mineralização, pois nela se encontraram as maiores anomalias de Au, Ag e Hg. Regionalmente, foram identificadas outras áreas de alteração situadas fora dos perímetros do prospecto Salares Norte, usando-se a técnica APC (Técnica Crósta) numa imagem ETM+ do satélite Landsat-7, e na imagem do sensor ASTER. Os resultados obtidos indicam ocorrências de zonas de alteração hidrotermal em áreas próximas a Salares Norte, com similaridades quanto ao tipo de assembléia mineral hidrotermal e controle estrutural, indicando estas áreas como alvos potenciais para mineralização de ouro e outros metais nesta região / Abstract: The main objective of the project was to evaluate the prospectivity potential for gold and associated metals of an area located in the northern part of the Maricunga Belt, Chile. Reflectance spectroscopy was used in the region of the Salares Norte Prospect to identify hydrothermal alteration mineral assemblages comprising kaolinite, smectite, alunite, illite and silica-bearing minerals. The presence of these minerals was confirmed by petrographic and electronic microscope (SEM) analyses. The spatial distribution of these minerals was determined by applying the following digital processing techniques to a Terra/ASTER scene: Principal Component Analysis (APC), Spectral Angle Mapper (SAM) and Mixed Tuned Matched Filter (MTMF). The accuracy of each resulting map was calculated, using as reference reflectance spectroscopy data obtained. The result showed APC as the most accurate technique with an overall accuracy of 44.34%. Although this value is relatively low, the less accurate data were found in regions with no alteration, whereas higher accuracy values were spatially related to altered regions, thus the ones with more interest. The spectral-mineralogical information was used together with geochemical (ICP-MS) and lithological data to analyze alteration assemblages in Salares Norte, showing that they were formed under epithermal conditions, most specifically in a high sulfidation environment, which currently shows a shallow erosion level. The alteration types identified in the prospect were argillic (kaolinite±smectite), advanced argillic (quartz+alunite+kaolinite) and siliceous in the core of the system. A late steam-heated alteration was recognized in a broad area, overprinting the advanced argillic and siliceous alteration in almost all its extension. The alteration zones exhibit an evident structural trend along NW-SE that coincides with Au, Ag and Hg geochemical anomalies. For this reason, the directional structural component appears to have acted as a possible alteration/mineralization control in Salares Norte. Within the lithological units identified in the prospect, a phreatomagmatic breccia stands out as a probable carrier/concentrator of mineralization, since the higher Au, Ag and Hg geochemical anomalies are associated with this unit. Other hydrothermally altered areas were identified in the region surrounding Salares Norte prospect using the APC technique (Crósta Technique) on an Landsat-7/ETM+ image, and also on an ASTER image, depicting similar aspects regarding the type of alteration assemblage and structural control, indicating these areas as potential targets for gold and other metals / Mestrado / Geologia e Recursos Naturais / Mestra em Geociências

No description available.

The Townlands iron-rich ultramafic pegmatite is a relatively large pipelike body situated in the western corner of Rustenburg Section, Rustenburg Platinum Mines. It is characterised by a strong negative magnetic signature and transgresses the noritic layered sequence of the upper critical zone of the Bushveld Complex. The layered rocks are downwarped in the vicinity of the pipe and are in sharp contact with the pegmatitic material. The pegmatite varies in composition between dunite and wehrlite, with the marginal zones being more wehrlitic in composition. Olivine (Fo₃₀ - Fo₅₂) and clinopyroxene (Wo₄₅En₃₀Fs₂₅ - Wo₄₅En₃₇Fs₁₈) are the dominant constituents and accessory phases include ilmenite, Ti -magnetite, apatite, amphiboles, chlorite-group minerals, biotite, ilvaite and a host of unusual ore minerals. The Fe-Ti oxides exhibit exsolution textures typically found in slowly cooled igneous rocks and temperatures of formati on are consi dered to be in excess of 800°C. The UG2 chromitite leader layers intersected by borehole TLP.l are enriched in Fe and Ti and exhibit compositions intermediate between chromite and Ti-magnetite. The ore mineral assemblage includes a primary sulphide assemblage consisting of troilite, chalcopyrite, cubanite and pentlandite, and an array of unusual phases formed by late-stage secondary processes. The unusual sulphides mooihoekite and haycockite, that occur in certain parts of the pegmatite, are considered to have formed by partial replacement of the primary assemblage and a possible paragenetic sequence is discussed. Mineral compositions and whole rock geochemical data are consistent with an origin for the pegmatite by crystallization from a fractionated melt. It is suggested that intercumulus fluids, trapped during the crystallization of the noritic layered sequence, accumulated in an area of structural weakness, in response to an increasing overburden pressure and/or tectonic activity. Evidence is also presented that indicates that the Townlands pegmatite may consist of at least two separate, but adjoining pegmatite bodies. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

This research study is more of an initiative towards Social Impact Assessment of copper-nickel mining in Botswana. The specific objectives of the study were centred on the assessment of the social impacts of copper-nickel mining in Botswana from the initial mining stage of exploration, surveying and mine site development to mine closure. The study was carried out under the broad hypotheses that mining influences population movement that impact on areas of mining; mining activities have both economic benefits and deleterious social impacts on the local communities found in the areas where mining is taking place; and mine closure has far reaching socio-economic, investment and developmental implications over and above the obvious interests of project owners. To achieve the broad aim as summarised above, the research study used a multi-disciplinary methodology and approach that required several kinds of expertise and sources of information. Hence it used both primary and secondary sources centred on interactive informative interviews, site visits and observations, questionnaires, census data records, mining companies’ publications, published textbooks and journal articles. The research study comprised of three different mines operated by three different mining companies in three varied socio-cultural and ethnic regions of Botswana. First was a detailed Social Impact Assessment of the initial phase of exploration, surveying and mine site development represented by Mowana mine project operated by African Copper in the rural areas of Dugwi and Mosetse. This case study yielded results showing that the social impacts of mining in the area are diverse and extensive. The findings suggest that the impacts relate not only to the possible economic benefits of foreign exchange, employment, the optimal use of available mineral resources and the possible development of Dugwi and Mosetse villages, but extends to the deleterious social impacts. The results also indicated that the social impacts have just begun in the two communities. Hence they point towards a possible disruption within the socio-cultural system of the local people if serious mitigation measures are not put in place; thus suggesting that the early stages of exploration and mine site development results in the most conflict between the mine and the local people. Second was a comprehensive Social Impact Assessment of Tati-Nickel Phoenix mining project in the peri-urban areas of Matshelagabedi and Matsiloje areas representing the mining stage of mine production and expansion. The results from this case study suggest that during vi mine production and expansion, many people were relocated. However, the overriding impression gained from the case study was Tati-Nickel Mining Company’s elaborate corporate policies that suggested good corporate governance and best practices that promote sustainable development. A notable milestone on good corporate governance and best practice that the other two case studies (mining company) could benchmark on is Tati-Nickel’s corporate social responsibility programme that has been designed to ensure that the communities within a fifty kilometre mine radius benefit from the mine. The results from the case study also distinguished the mining stage of production and expansion from the other two because it is associated with the deep entrenchment of the social impacts into the communities near to mining areas. Third was a detailed Social Impact Assessment on Bamangwato Concession Limited mine in the industrial town of Selebi-Phikwe. The case study represented the stage of mine closure. Through the findings of this case study, it became apparent that the economic dependence of Selebi-Phikwe on mining has seen the town developing into a mining town, increasing its vulnerability at mine closure. The results from the case study further suggest that mine closure will degrade the socio-economic sector of the town with ever far reaching socio-economic implications as many people lose their gainful employment, hence suggesting that a possible complete mine closure will be the most traumatic phase leading to major social conflict within the area. Thus the results suggest that at mine closure, the deleterious social impacts will overspill to other areas in Botswana with disastrous effects for the economy of the country. The results yielded through this study established in clear and passionate language that copper-nickel mining in Botswana influences population movements that lead to positive and negative impacts on the communities found in mining areas. Another major finding of the study is that copper-nickel mining activities have both economic benefits and deleterious social impacts on the local communities, hence the recommendation that the copper-nickel mining companies should embrace the concept of sustainable mining for sustainable development to avoid most of the negative impacts of their operations on the local communities.

South Africa has less than 1 percent of the global land surface, yet it is ranked highly in terms of remaining mineral resources. Mineral wealth has not translated into a better life for all. Poverty, however, abounds; particularly in the rural areas and this study seeks to identify a solution or partial solution to this situation. The study combines two critical areas, Mineral Based Rural Development, and Mineral Based Enterprise Development and draws from it a model for Mineraldriven Rural Economic Development viable for all parts of South Africa. This study comprised research on a national scale and thus covered a section of each of South Africa‟s nine provinces. It investigated the conditions in rural and urban centres, and geologically, it traversed examples of Archaean, Proterozoic and Phanerozoic formations. The field visits deliberately set out to look at some of the lowest value commodities; typically the only minerals available to the surrounding rural communities. This was done to see if a case could be made for even the lowest value commodities which are often found furthest from the large markets. This study indicates that for a rural area to be able to compete nationally or internationally, it is important to be competitive so that the area can participate in the economy. The creation of regional competitive areas allow for the focusing of strategies and funding for targeted rural projects. Enterprises, typically the product of entrepreneurial activity, are required to increase economic intensity and activity. xxvii The goal of poverty reduction, has been identified by government so that enterprises, as products of economic development, can be focused on the situation. Interviews conducted by the researcher indicated that part of the problem to overcome is the bureaucracy created by government which hinders enterprise development. Recommendations are made that government should exempt rural enterprises from some of the compliance hurdles. This will serve to accelerate rural development. An important aspect of urban enterprises is that they have access to labour without too many problems. Thirteen developed or developing corridors were visited of the five types of development corridors identified. It was found that those in areas of high poverty (for example the corridors of the Eastern Cape) are difficult to develop and make self-sustaining. The corridors linked to any point of Gauteng (Johannesburg or Pretoria) are more robust, although the relatively short length of the corridor is not an indicator of effectiveness. The key recommendations made include the completion of a national rural mineral-asset audit; the use of the information to demarcate rural-regions that can be developed as nationally and internationally competitive regions; the establishment of a rural Resource and Training Academy(ies) so that skills are developed close to areas where they will be deployed; provision of an easier way to launch mineral-based rural enterprises and incentivise these for accelerated development; and the development of an indigenous body of knowledge to mine small scale deposits

No abstract included. / Arts, Faculty of / History, Department of / Graduate

One hundred surface sediment samples and two 30 cm cores were collected from Howe Sound, British Columbia, a deep (≈280 m) fjord with a restricted inner basin into which mine tailings had been dumped for 75 years. The abundances of major elements Si, Al, Ti, Fe, Mg, Ca, Na, K, C, N, and P, and minor elements Ba, Co, Cr, Cu, Mn, Ni, Pb, Rb, Sr, V, Y, Zn, and Zr were determined as well as nutrient and trace metal concentrations in porewater from the two cores. The solid-phase data suggest that the inner basin sediments are dominated by Squamish River-derived feldspars, while the outer basin is characterized more by quartz and Fe and Mg minerals, which enter the southernmost portion of the fjord via estuarine circulation from Georgia Strait. Although Fe, Cu, Pb, Zn, and Ba are still enriched in sediments near the tailings outfall, the lapse of 13 years since cessation of tailings deposition has apparently resulted in reduced metal levels throughout much of the rest of the inlet due to ongoing dilution by natural sedimentation. Profiles of these metals with depth show that the tailings deposit proper is buried by ≈14 cm of natural sediment in the deep central portion of the inner basin. Porewater analysis of the two cores revealed that active bacterial remobilization of organic matter is occurring at both locations; although the organic carbon content of the outer basin is greater than that in the inner basin, sulphate-reduction is more intense in the latter due to the higher sedimentation rate. Despite this, dissolved sulphides were nearly absent in porewaters, leading to the conclusion that authigenic pyrite precipitation is removing some of the dissolved Fe. Dissolved Cu and Zn are enriched in surficial porewaters of both the outer and inner basins (i.e. Cu = 215 and 132 nmol/L, respectively, and Zn = 32 µmol/L and 1.6 /µmol/L), but decrease rapidly within the top 2-3 cm, suggestive of active removal by some mechanism. Dissolved Pb concentrations were low (<3 nmol/L) in both cores, and did not show any surface enrichment. These data suggest that a strongly reducing environment such as is found at depth in natural sediments inhibits the release of some labile metals which may be contained within them. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

M.Comm. (International Taxation) / Lyn Bourne (n.d.) once wrote "The concept of royalties evolved from a time when the government owned all of the land, including mines, to the situation where free miners won the right to claim minerals, but paid a portion of their production to the royal treasury. Today, a mineral royalty is a payment to the owner of the mineral rights for the privilege of producing the mineral commodity"...

A presente pesquisa examina a mineração de agregados para a construção civil e o tratamento dispensado no processo legislativo que visa instituir um novo marco regulatório para mineração brasileira. O escopo da pesquisa é verificar a pertinência de tratamento específico aos agregados minerais sob a ótica do princípio do desenvolvimento sustentável. A metodologia aplicada evidencia ser fundamental contextualizar a proposta legal, conceituar e compreender os bens e a atividade minerária, diferenciando os minerais agregados dos demais minérios. Verificadas suas especificidades, a mineração de agregados é analisada sob a ótica da sustentabilidade. O referencial teórico de José Eli da Veiga, na obra “Desenvolvimento sustentável: o desafio do século XXI” orienta a pesquisa no sentido de tecer as relações da atividade com o meio ambiente e a dignidade da pessoa humana. A pesquisa ressalta os impactos causados pela atividade, negativos ao meio ambiente e positivos no alcance da melhoria da qualidade de vida das pessoas. O estudo faz referência ao Direito Mineral Brasileiro e estudar o PL n. 5.087/2013 e seu substitutivo, reivindica aporte sobre políticas públicas e acerca do processo legislativo em tramitação. Ao final analisa os regimes de aproveitamento mineral, especificando o regime da autorização, a pesquisa mineral, a proposta acerca de ordenamento territorial mineral, a compensação financeira sobre a exploração mineral (CFEM) e quanto ao poder concedente dos direitos minerários. Pode-se concluir e confirmar a hipótese levantada que a legislação sempre privilegiou os minerais agregados dada sua essencialidade no alcance da melhoria da qualidade de vida, sendo imprescindível que seja mantido este direcionamento no tratamento deste bem social para alcance da sustentabilidade, enquanto preceito em processo de construção. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / The research presents an approach of mining of aggregates for construction and the treatment designated in the legislative process which is being prepared to establish a New Regulatory Framework for Brazilian Mining. The scope of the research is to verify the relevance of specific treatment to mineral aggregates from the perspective of sustainable development. The applied methodology showed to be critical to contextualize the legal proposal, conceptualize and understand the assets and mining activities, differentiating the mineral aggregates of other mineral resources. Due to its specificities, mining of aggregates was analyzed from the perspective of sustainability. The theoretical reference of José Eli da Veiga, in the book "Sustainable development: the challenge of the XXI century" has oriented the research in order to identify relations of mining of aggregates to the environment and human dignity. The research highlighted the impacts caused by mining of aggregates, negative for the environment and positive due to improving quality of life. The study refers to The Brazilian Mineral Law, the Law Project n° 5087/2013, and its replacement, that inputs public policy. At the end, mineral exploitation regimes were analyzed, specifying the “regime of authorization”, mineral exploration, the proposal concerning mineral land planning, the financial compensation for mineral exploration (CFEM) and the mining rights. It was possible to conclude and confirm the hypothesis that the law has always privileged the mineral aggregates given its essentiality to improve quality of life and it is essential to maintain this condition to achieve sustainability while precept in process of construction.