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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Matriz de priorização aplicada à pesquisa mineral na pequena mineração. / Priority matrix applied to mineral exploration in small-scale mining.

Ricardo Marcelo Tichauer 01 November 2016 (has links)
Na mineração, grande parte das incertezas e riscos estão associados à caracterização geológica. A adoção das melhores práticas na pesquisa mineral resulta em menor risco e maiores eficácia e eficiência à operação, agregando valor ao empreendimento. No Brasil, em geral, a mineração em pequena escala emprega poucos recursos para a pesquisa mineral, e as melhores práticas são frequentemente ignoradas. Este trabalho aborda a incerteza geológica na mineração e como as melhores práticas de pesquisa mineral podem ser aplicadas na pequena mineração para diminuir riscos e incorporar valor ao projeto. A aplicação da Matriz de Priorização CEBIm em três projetos de pesquisa mineral em pequenos depósitos mostra como essa ferramenta pode ser utilizada de forma simples, prática, rápida e econômica para avaliação do nível de aderência do programa de pesquisa mineral às melhores práticas, que pode indicar a magnitude da incerteza geológica associada ao projeto. / In mining, a large number of uncertainties and risks are associated with geological characterization. The adoption of best practices in mineral exploration results in lower risk and greater effectiveness and efficiency to the operation, adding value to the enterprise. In Brazil, in general, small-scale mining employs little resources for mineral exploration, and the best practices are often ignored. This work addresses the geological risks in mining and how best practices in mineral exploration can be applied in small mining to reduce risks and incorporate value to the project. The application of the CEBIm Priority Matrix in three projects of mineral exploration in small deposits shows how this tool can be utilized in a simple, practical, fast and economical way for assessment of the level of compliance of the mineral exploration program to the best practices, which can indicate the magnitude of geological uncertainty associated with the project.
32

Qualidade da paisagem do município de Japaratuba/SE e sua relação com o campo petrolífero de Carmópolis

Menezes, Daniela Monique Guimarães 28 February 2018 (has links)
The mineral exploration of petroleum is an integrant part of an extensive production chain that starts with the accomplishment of previous studies that seek to define the viability of the establishment of the activity and is finished with the commerce of the most varied products and by-products, whose raw material is petroleum. In order to regulate this activity and due to its greatness, which, in addition to being extensive, is burdensome and impactful to the environment, oil exploration is based on the national energy policy, instituted through Federal Law 9.478 / 1997. Therefore, the oil exploitation makes it essential to adapt all the steps related to this activity, in accordance with the precepts of sustainable development, through environmental licensing, which is an instrument of environmental management, instituted by Federal Law nº 6.938/1981, which uses constraints to control negative impacts, either by mitigating or compensating them. It stands out that each stage of onshore oil exploration is subject to environmental licensing by the competent environmental agency of the states. The impacts of oil exploration on the continental shelf directly affect economic, social and environmental aspects, all related to landscape changes. In this way, this research analyzed the quality of the landscape and its relation with the Petroleum Field of Carmópolis, through the mapping of the land use in the municipality of Japaratuba; identification of landscape components; the mapping of landscape quality in the municipality; and the definition of the Japaratuba's Landscape Quality Index for the years 2003 and 2017, comparing them to each other There were identified 11 classes of land use, with the most representativity the ones with economical being. In the year 2017, the Pasture class represented more than 50% of the occupation of the municipal space, corresponding, therefore, to the matrix of the landscape that influences and is influenced by other classes of land use identified in the municipality of Japaratuba, being the most impacting, among them, the oil exploration. In both years, the quality of the landscape in Japaratuba remained unchanged, being classified as regular. / A exploração mineral do petróleo é parte integrante de uma extensa cadeia produtiva iniciada com a realização de estudos prévios que buscam definir a viabilidade do estabelecimento da atividade e finalizada com o comércio dos mais variados produtos e subprodutos, cuja matériaprima é petróleo. Para a regulamentação desta atividade e devido a sua grandiosidade que, além de extensa, é onerosa e impactante ao meio ambiente, a exploração petrolífera está pautada na política energética nacional, instituída por meio da Lei Federal nº 9.478/1997. Assim sendo, a exploração do petróleo torna imprescindível a adequação de todas as etapas relacionadas à esta atividade, de acordo com os preceitos do desenvolvimento sustentável, através do licenciamento ambiental, que é um instrumento de gestão ambiental, instituído pela Lei Federal nº 6938/1981, que utiliza condicionantes para o controle de impactos negativos, seja mitigandoos ou compensando-os. Ressalta-se que cada etapa da exploração de petróleo onshore é passível de licenciamento ambiental realizado pelo órgão ambiental estadual competente. Os impactos da exploração petrolífera na plataforma continental afetam diretamente aspectos econômicos, sociais e ambientais, estando todos estes relacionados às alterações da paisagem. Desta maneira, esta pesquisa analisou a qualidade da paisagem e a sua relação com o Campo Petrolífero de Carmópolis, através do mapeamento do uso do solo no município de Japaratuba; da identificação dos componentes da paisagem; do mapeamento da qualidade da paisagem no município; e da definição do Índice de Qualidade da Paisagem de Japaratuba para os anos de 2003 e 2017, comparando-os entre si. Foram identificadas 11 classes de uso do solo, sendo as mais representativas aquelas com finalidade econômica. A classe da Pastagem representou, no ano de 2017, mais de 50% da ocupação do território municipal, correspondendo, portanto, à matriz da paisagem que tanto influencia quanto é influenciada pelas outras classes de uso do solo identificadas no município de Japaratuba, sendo a mais impactante, entre estas, a exploração petrolífera. Em ambos os anos estudados, a qualidade da paisagem em Japaratuba permaneceu inalterada, sendo classificada como regular. / São Cristóvão, SE
33

Three-dimensional modelling of the Källfallsgruvan iron oxide deposit, Riddarhyttan ore field, Bergslagen, Sweden: Integrating existing and new data to aid understanding of structural controls and mineral exploration

Spahic, Edna January 2021 (has links)
The Bergslagen ore province, located in the Fennoscandian shield in the south-central part of Sweden hosts several metallic mineral deposits, one of them being the Källfallsgruvan iron-oxide deposit in the Riddarhyttan ore field, situated in a high-strain shear belt denoted as the West Bergslagen Boundary Zone (WBBZ).  An accurate 3D geological model of the Källfallsgruvan iron-oxide deposit has been generated to aid understanding of the ore body geometries and calculating volume and tonnage. The methodology of this study consisted of assessing existing data in the form of legacy mine maps and to integrate new data from field work, drill core logging and 3D geological modelling. The work has resulted in structural interpretations that are put in the context of the regional structural framework in Bergslagen consisting of three deformation events (D1, D2 and D3) and two metamorphic events (M1 and M2). The field work resulted in six rock units being defined used to construct a geological map, in addition the structural measurements resulted in a hypothetical semi-regional fold and evidence of ductile strike-slip/dip-slip shearing. Logging of drill cores resulted in three rock units being defined, two of them related to the mineralization and one characterizing the host rock (± local variations), correlating to the observed host rock from the field work. The rock units discovered from both the field work and drill core logging are all interpreted to be the metamorphic products of volcanic rocks subjected to alteration of varying degree. Based upon geological field observations with subsurface data and 3D geological modelling it is concluded that, 1) The deposit comprises multiple ore bodies that jointly resemble an S-shaped synform that is steeply inclined-upright, moderately-steeply plunging towards the southwest with an axial plane striking northeast-southwest. The deposit is interpreted to be geometrically controlled by an F2 fold, possibly displaying an interference pattern of type 1, favouring progressive shearing and deformation solely related to D2, 2) Evidence of at least one generation of transpressional tectonic regime exists, interpreted to be D2, 3) The estimated tonnage of 4 938 610 tons of the massive magnetite and semi-massive mineralization revealed that a deposit of such tonnage is presently not economically viable. However, if the Källfallsgruvan iron-oxide deposit or similar is determined to have a significant REE content, such deposit may then be of economic interest and, 4) Possible mineral exploration indicators around Källfalls-like deposits are intensely altered rocks related to magnesium alteration, consisting dominantly of quartz, biotite (increasing towards mineralization), muscovite, chlorite, anthophyllite and cordierite, affected by parasitic folding. / Bergslagen malmprovins, belägen i den Fennoskandiska skölden i sydcentrala delen av Sverige innehåller flera metall mineralfyndigheter, varav en av dem är Källfallsgruvan järnoxidfyndighet i Riddarhyttan malmfält, belägen i en skjuvzon kallat för ”West Bergslagen Boundary Zone (WBBZ)”. En representativ 3D geologisk model av Källfallsgruvan järnoxidfyndighet har genererats för att öka förståelsen av malmkroppens geometrier samt beräkna volym och tonnage. Metodiken bestod av att bedöma existerande data så som gruvkartor och integrera nya data genom fältarbete, borrkärnekartering och 3D geologisk modellering. Arbetet resulterade i strukturella tolkningar som sattes i kontexten av den regionala strukturella bilden i Bergslagen bestående av tre deformations event (D1, D2 och D3) och två metamorfa event (M1 och M2). Fältarbetet resulterade i att sex bergartsenheter definierades som användes för att konstruera en geologisk karta samt så har de strukturella mätningarna resulterat i ett hypotetiskt semi-regionalt veck och bevis för duktil strike-slip-/normal-skjuvning. Borrkärnekarteringen resulterade i att tre bergartsenheter definierades, varav två var relaterade till mineraliseringen och en kännetecknade värdbergarten (± lokala variationer) som korrelerar med den observerade värdbergarten från fältarbetet. Bergartsenheterna som upptäcktes från både fältarbetet och borrkärnekarteringen har tolkats vara metamorfa produkter av vulkaniska bergarter som omvandlats i varierande grad. Baserat på de geologiska fältobservationerna med underjordsdata och 3D geologisk modellering dras följande slutsatser, 1) Fyndigheten består av multipla malmkroppar som gemensamt liknar en S-formad synform som är brant lutande-upprätt, måttligt-brant stupande mot sydväst med ett axialplan som stryker nordost-sydväst. Fyndigheten tolkas vara geometriskt kontrollerat av ett F2 veck, som möjligtvis påvisar ett interferensmönster av typ 1 bildat genom progressiv skjuvning och deformation endast relaterat till D2, 2) Bevis för minst en generation av transpressionstektonisk miljö existerar vilket tolkats vara D2, 3) Det estimerade tonnaget på 4 938 610 ton för den massiva magnetit och semi-massiva mineraliseringen visade att en fyndighet av sådant tonnage är för nuvarande inte ekonomiskt hållbart. Om Källfallsgruvan järnoxidfyndighet eller liknande fyndighet bestäms att ha ett betydande REE innehåll så skulle en sådan fyndighet vara av ekonomiskt intresse och, 4) Möjliga prospekteringsindikatorer runt Källfalls-liknande fyndigheter är intensivt omvandlade bergarter relaterad till magnesiumomvandling främst bestående av kvarts, biotit (ökar mot mineraliseringen), muskovit, klorit, antofyllit och kordierit, påverkad av parasitisk veckning.
34

Crustal architecture of the Kiruna mining district : Structural framework, geological modeling, and physical rock property distribution

Veress, Ervin Csaba January 1900 (has links)
Rapid technological advancements and growing environmental consciousness created a shifting dynamic of metal demand within the context of contemporary global challenges. The metals play a pivotal role in this transformation and remarkable surge in demand is expected. Mining districts such as the Kiruna area in northern Sweden, provide access to raw materials, assuring supply chain security, sustainability, and an environmentally friendly future. The district is part of the northern Norrbotten ore province, Sweden and is known for hosting the Kiruna-type iron oxide-apatite (IOA) deposits with associated magnetite-hematite-REE ores such as the Per Geijer deposits, and a range of other deposits, including the Viscaria Cu-(Fe-Zn), Pahtohavare Cu-Au and the Rakkurijärvi iron oxide-copper-gold (IOCG) deposits.  As the discoveries of significant near-surface deposits are declining, mining companies face a pivotal choice between pursuing resource extraction from lower-grade reserves or to focus on deeper exploration targets. The geological understanding of the subsurface decreases with increasing depth, and the reliance on geophysical techniques becomes more important in reducing the search space. Using geophysics to locate and understand elements of a mineral system requires a good understanding of the physical and chemical properties of the rocks that can be translated into geological implications. Mineral system knowledge and geological concepts can be translated into geological models that can be further used in geophysical inversions with the aim of improving targeting by iterative modeling. A geophysical inversion is in fact a realization of a physical property model, therefore the value added by the geophysical model is dependent of how well the relationship between the geology and its petrophysical signature is understood. The petrophysical characterization of geological environments offers the possibility to improve the understanding of geophysical responses, serving as a link in iterative geological-geophysical modeling.  The approach presented in the current study includes the building of three-dimensional lithological and structural framework models, and investigating the petrophysical footprint in connection with lithology, alteration, and rock fabric from the Kiruna mining district. Geological modeling and petrophysical characterization are important components within the comprehensive mineral system modeling framework and enhance geophysical investigations aimed at detecting and assessing iron oxide mineral systems. A rule-based hybrid implicit-explicit geological modeling technique proved to be useful in the integration of surface and subsurface data of the Kiruna mining district, and a structural framework and geological model was produced that provides insights into the relationship between lithological units and structures. Drill core observations indicate a competency contrast between lithological units confirming previous surface-based observations. Deposit scale structural analysis in connection with the geological models indicated the proximity of NW-SE to SW-NE trending brittle conjugate fault networks with iron-oxide apatite ore lenses, revealing juxtaposition of individual ore lenses. Complementing structural analysis and geological modeling, petrophysical characterization in connection with lithogeochemical, mineralogical, and textural investigations revealed that density and p-wave seismic velocity can be used as a general lithological indicator, while magnetic susceptibility is influenced by secondary processes. Heterogeneous strain accommodation by lithological units indicates a strong influence on density, seismic properties, and the ferromagnetic properties of the samples. Metasomatic processes alter the intrinsic properties of the samples by increasing or decreasing the physical properties of the rocks from the Kiruna area, by controlling the feldspar, mica, magnetite, and ferromagnesian mineral content. Nevertheless, an extensive sample population must be investigated to understand the large-scale effects. The present work serves as a foundation for quantitatively integrated exploration models that use geological models and petrophysical characterization as calibration tools to model mineral systems.
35

Patterns of distal alteration zonation around Antamina Cu-Zn skarn and Uchucchacua Ag-base metal vein deposits, Peru : mineralogical, chemical and isotopic evidence for fluid composition, and infiltration, and implications for mineral exploration

Escalante Aramburu, Abraham David 11 1900 (has links)
Intrusion-related, carbonate rock–hosted replacement deposits are an important source of global base metal production that includes: Cu-Zn skarn, Zn-Pb-Ag carbonate replacement and Ag-base metal deposits. These deposits are located in multiple geological settings and are commonly associated with low-grade Cu-Mo calc-alkaline porphyry districts. Visible alteration halos to these deposits range from ten to hundreds of metres around high temperature skarn deposits, being small to imperceptible around the distal relatively low temperature members of this clan. Patterns of visible and cryptic alteration are described and constrained in this study particularly around paleo-fluid flow zones at different distances and elevations from the ore centre. This was done in order to identify the large-scale zonation, mechanisms, and effects of fluid infiltration especially into the distal portions of these deposits. The main alteration tracers employed included mineralogy, major and trace element geochemistry, oxygen and carbon isotopes, and the fluorescent signature of calcite veins associated with the fluids conduits. Two areas were selected for this study: the large Cu-Zn Antamina skarn and the Ag-base metal Uchucchacua vein deposits in the Peruvian Central Andes as these deposits represent the end-members of the polymetallic carbonate rock-hosted deposits and hence, provide an excellent opportunity to examine the margins and upper sections of these hydrothermal systems. Geochronological analyses of intrusive dikes were used to establish the magmatic and hydrothermal evolution associated with mineralization, as well as the genetic linkage between proximal and distal portions of the mineralizing system at Antamina. Oxygen, carbon and strontium isotope data of vein minerals is also used to constrain the temperature of the fluids proximal and distal to the magmatic centre. Chemical data of fluorescent and non-fluorescent veins were used to determine the main activators of fluorescence and to constrain its relationship with mineralizing fluids. In summary, results of this research identify a large-scale zonation of visible and cryptic alteration around paleo-fluid flow zones demonstrating the linkage between Ag-base metal veins, replacement and skarn deposits. Anomalous halos determined throughout Antamina and Uchucchacua deposits may contribute to the development of a more systematic exploration methodology for these types of deposits.
36

Patterns of distal alteration zonation around Antamina Cu-Zn skarn and Uchucchacua Ag-base metal vein deposits, Peru : mineralogical, chemical and isotopic evidence for fluid composition, and infiltration, and implications for mineral exploration

Escalante Aramburu, Abraham David 11 1900 (has links)
Intrusion-related, carbonate rock–hosted replacement deposits are an important source of global base metal production that includes: Cu-Zn skarn, Zn-Pb-Ag carbonate replacement and Ag-base metal deposits. These deposits are located in multiple geological settings and are commonly associated with low-grade Cu-Mo calc-alkaline porphyry districts. Visible alteration halos to these deposits range from ten to hundreds of metres around high temperature skarn deposits, being small to imperceptible around the distal relatively low temperature members of this clan. Patterns of visible and cryptic alteration are described and constrained in this study particularly around paleo-fluid flow zones at different distances and elevations from the ore centre. This was done in order to identify the large-scale zonation, mechanisms, and effects of fluid infiltration especially into the distal portions of these deposits. The main alteration tracers employed included mineralogy, major and trace element geochemistry, oxygen and carbon isotopes, and the fluorescent signature of calcite veins associated with the fluids conduits. Two areas were selected for this study: the large Cu-Zn Antamina skarn and the Ag-base metal Uchucchacua vein deposits in the Peruvian Central Andes as these deposits represent the end-members of the polymetallic carbonate rock-hosted deposits and hence, provide an excellent opportunity to examine the margins and upper sections of these hydrothermal systems. Geochronological analyses of intrusive dikes were used to establish the magmatic and hydrothermal evolution associated with mineralization, as well as the genetic linkage between proximal and distal portions of the mineralizing system at Antamina. Oxygen, carbon and strontium isotope data of vein minerals is also used to constrain the temperature of the fluids proximal and distal to the magmatic centre. Chemical data of fluorescent and non-fluorescent veins were used to determine the main activators of fluorescence and to constrain its relationship with mineralizing fluids. In summary, results of this research identify a large-scale zonation of visible and cryptic alteration around paleo-fluid flow zones demonstrating the linkage between Ag-base metal veins, replacement and skarn deposits. Anomalous halos determined throughout Antamina and Uchucchacua deposits may contribute to the development of a more systematic exploration methodology for these types of deposits.
37

Feasibility of rock characterization for mineral exploration using seismic data

Harrison, Christopher Bernard January 2009 (has links)
The use of seismic methods in hard rock environments in Western Australia for mineral exploration is a new and burgeoning technology. Traditionally, mineral exploration has relied upon potential field methods and surface prospecting to reveal shallow targets for economic exploitation. These methods have been and will continue to be effective but lack lateral and depth resolution needed to image deeper mineral deposits for targeted mining. With global need for minerals, and gold in particular, increasing in demand, and with shallower targets harder to find, new methods to uncover deeper mineral reserves are needed. Seismic reflection imaging, hard rock borehole data analysis, seismic inversion and seismic attribute analysis all give the spatial and volumetric exploration techniques the mineral industry can use to reveal high value deeper mineral targets. / In 2002, two high resolution seismic lines, the East Victory and Intrepid, were acquired along with sonic logging, to assess the feasibility of seismic imaging and rock characterisation at the St. Ives gold camp in Western Australia. An innovative research project was undertaken combining seismic processing, rock characterization, reflection calibration, seismic inversion and seismic attribute analysis to show that volumetric predictions of rock type and gold-content may be viable in hard rock environments. Accurate seismic imaging and reflection identification proved to be challenging but achievable task in the all-out hard rock environment of the Yilgarn craton. Accurate results were confounded by crocked seismic line acquisition, low signal-to-noise ratio, regolith distortions, small elastic property variations in the rock, and a limited volume of sonic logging. Each of these challenges, however, did have a systematic solution which allowed for accurate results to be achieved. / Seismic imaging was successfully completed on both the East Victory and Intrepid data sets revealing complex structures in the Earth as shallow as 100 metres to as deep as 3000 metres. The successful imaging required homogenization of the regolith to eliminate regolith travel-time distortions and accurate constant velocity analysis for reflection focusing using migration. Verification of the high amplitude reflections within each image was achieved through integration of surface geological and underground mine data as well as calibration with log derived synthetic seismograms. The most accurate imaging results were ultimately achieved on the East Victory line which had good signal-to-noise ratio and close-to-straight data acquisition direction compared to the more crooked Intrepid seismic line. / The sonic logs from both the East Victory and Intrepid seismic lines were comprehensively analysed by re-sampling and separating the data based on rock type, structure type, alteration type, and Au assay. Cross plotting of the log data revealed statistically accurate separation between harder and softer rocks, as well as sheared and un-sheared rock, were possible based solely on compressional-wave, shear-wave, density, acoustic and elastic impedance. These results were used successfully to derive empirical relationships between seismic attributes and geology. Calibrations of the logs and seismic data provided proof that reflections, especially high-amplitude reflections, correlated well with certain rock properties as expected from the sonic data, including high gold content sheared zones. The correlation value, however, varied with signal-to-noise ratio and crookedness of the seismic line. Subsequent numerical modelling confirmed that separating soft from hard rocks can be based on both general reflectivity pattern and impedance contrasts. / Indeed impedance inversions on the calibrated seismic and sonic data produced reliable volumetric separations between harder rocks (basalt and dolerite) and softer rock (intermediate intrusive, mafic, and volcaniclastic). Acoustic impedance inversions produced the most statistically valid volumetric predictions with the simultaneous use of acoustic and elastic inversions producing stable separation of softer and harder rocks zones. Similarly, Lambda-Mu-Rho inversions showed good separations between softer and harder rock zones. With high gold content rock associated more with “softer” hard rocks and sheared zones, these volumetric inversion provide valuable information for targeted mining. The geostatistical method applied to attribute analysis, however, was highly ambiguous due to low correlations and thus produced overly generalized predictions. Overall reliability of the seismic inversion results were based on quality and quantity of sonic data leaving the East Victory data set, again with superior results as compared to the Intrepid data set. / In general, detailed processing and analysis of the 2D seismic data and the study of the relationship between the recorded wave-field and rock properties measured from borehole logs, core samples and open cut mining, revealed that positive correlations can be developed between the two. The results of rigorous research show that rock characterization using seismic methodology will greatly benefit the mineral industry.
38

Vegetation as a biotic driver for the formation of soil geochemical anomalies for mineral exploration of covered terranes

Ma, Yamin January 2008 (has links)
[Tuncated abstract] Soil is a relatively low cost and robust geochemical sampling medium and is an essential part of most mineral exploration programs. In areas of covered terrain, however, soils are less reliable as a sampling medium because they do not always develop the geochemical signature of the buried mineralisation; possibly a result of limited upward transport of ore related elements into the surficial overburden. As economic demands on the resources industry grow, mineral exploration continues to expand further into areas of covered terrain where the rewards of finding a new deposit relative to the risks of finding it may be comparatively low. Thus, improving the costeffectiveness of a geochemical exploration program requires a sound understanding of the mechanisms by which soil geochemical anomalies form in transported overburden. This thesis examines the deep biotic uplift of ore related elements by deep rooting vegetation as a mechanism for the development of soil geochemical anomalies within transported overburdens, in semi-arid and arid regions. '...' Vegetation and soils were analysed at two Au prospects in Western Australia: Berkley, Coolgardie and Torquata, 210 km south-east of Kambalda, in semi-arid Western Australia to complement both the mass balance and the differential modelling. At Berkley, both the vegetation and soils located directly over the mineralisation showed high concentrations of Au. There may be indirect evidence for the operation of the deep plant uptake flux taking effect from the field evidence at Berkley. Firstly, anomalous concentrations of Au were found in the surface soils, with no detectable Au in the transported overburden. Secondly, the trace element concentrations in vegetation showed correlation to the buried lithology, which to our knowledge has not been reported elsewhere. The results from the samples at Torquata, in contrast, were less conclusive because the Au is almost exclusively associated with a surficial calcrete horizon (at <5 m soil depth). Strong correlations of Ca and Au in leaf samples however, suggest that the vegetation may be involved in the formation of calcrete and the subsequent association of Au with the calcrete. Among the vegetation components, the litter and leaf samples gave the greatest anomaly contrast at both prospects. Finally, three main drivers for the deep biotic uplift of elements were identified based on the results from the mechanistic numerical modelling exercise: i) the deep uptake flux; ii) the maximum plant concentration and; iii) the erosional flux. The relative sizes of these three factors control the rates of formation and decay, and trace element concentrations, of the soil anomaly. The main implication for the use of soils as exploration media in covered terranes is that soil geochemical anomalies may only be transient geological features, forming and dispersing as a result of the relative sizes of the accumulative and loss fluxes. The thesis culminates in the development of the first quantitative, mechanistic model of trace element accumulation in soils by deep biotic uplift.
39

Mining Exploration in Peru: A Brief Scope on the Main Authorizations for the Development of an Exploration Project in Peru / La Exploración Minera en el Perú: Un Breve Alcance sobre las Principales Autorizaciones para el Desarrollo de un Proyecto de Exploración en el Perú

Pachas Pérez, Diego 10 April 2018 (has links)
The purpose of the author in this article is to outline the main licenses regarding mineral exploration and publicize the usual paperwork and contingencies obtaining these permits.It also presents alternatives to traditional procedures, which are more useful in practice to expedite to start of mining exploration activities in Peru. / El fin del autor en este artículo es hacer un esbozo de los principales títulos habilitantes para lo referente a la exploración minera, así como dar a conocer los trámites y usuales contingencias que acarrean la obtención de estos permisos. Asimismo, se presentanalternativas a las tradicionales autorizaciones, que son más útiles en la práctica para agilizarel comienzo de actividades de exploración minera en el Perú.
40

Fronteira da exploração mineral na Amazônia = o setor mineral e a dinâmica demográfica da mesorregião sudeste paraense / Frontier mineral exploration in the Amazon : the mining sector and demographic dynamics of the southeastern region of Para

Corrêa, Vinícius Moreno de Sousa, 1984- 19 August 2018 (has links)
Orientador: Roberto Luiz do Carmo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-19T03:29:42Z (GMT). No. of bitstreams: 1 Correa_ViniciusMorenodeSousa_M.pdf: 6381481 bytes, checksum: a40be21e01edc970c789fdc4086a4871 (MD5) Previous issue date: 2011 / Resumo: A exploração mineral na Amazônia deve ser entendida como um dos agentes de ocupação de uma das últimas fronteiras do país. O trabalho analisa a importância do setor mineral nos municípios da Mesorregião Sudeste Paraense, discutindo as implicações demográficas e ambientais decorrentes dos processos associados à atividade econômica. Embora os efeitos agudos dessa atividade sejam cíclicos - com a descoberta, exploração e exaustão das jazidas se sucedendo com velocidade variável - existem medidas de impacto que podem ser apreendidas ao longo do tempo. A descoberta e a exploração de uma jazida são capazes de desencadear processos demográficos, realizando transformações na estrutura populacional, que permanecem presentes mesmo após a diminuição ou o término da exploração. Vestígios desse processo específico de uso e ocupação do solo foram investigados através da composição de duas fontes secundárias em bases de dados georreferenciados. Por um lado, o Ministério de Minas e Energia, através do Departamento Nacional de Produção Mineral (DNPM), através do Sistema de Informações Geográficas de Mineração (SIGMINE), com as informações exigidas para o licenciamento mineral no Brasil. Por outro lado, o Instituto Brasileiro de Geografia e Estatística (IBGE) com as variáveis do Censo Demográfico 2000 e da Sinopse do Censo Demográfico 2010, além dos shapefiles com a delimitação espacial dos dados em diferentes níveis de desagregação. Entre os Censos 1991 e 2000, a mecanização da extração mineral reduziu significativamente o volume de trabalhadores ocupados no setor. Mas a dinâmica de "bolha demográfica", rápido ciclo de ocupação e esvaziamento populacional das áreas associadas ao garimpo, é apenas um dos processos possíveis. Na área de estudo, os municípios mais populosos e urbanizados concentram grande parte das áreas outorgadas pelo DNPM. Nesse caso, o volume de minério encontrado e a vida útil das jazidas exploradas foram capazes de atrair grandes investimentos para a região, porém, estes priorizaram a geração de riquezas, ao invés de expandir o acesso aos serviços de saneamento básico. O retrato das condições de vida da população revelou, com base nas características de infraestrutura domiciliar, uma situação de extrema carência na Mesorregião Sudeste Paraense / Abstract: Mineral exploration in the Amazon must be understood as an agent of occupation of Brazilian last frontier. This research analyzes the significance of mining sector in the municipalities of Pará State southeastern region, discussing the demographic and environmental implications arising from the process of occupation by this economic activity. Although the acute effects of this activity are cyclical - with the discovery, exploitation and exhaustion of deposits are succeeding with variable speed - there are impact measures that can be learned over time. The discovery and exploitation of a mineral deposit affects demographic processes, making changes in population structure, which remain even after the reduction or finish of exploration. Remains of that particular process of land use and land cover change were investigated by overlapping two secondary sources of georeferenced databases: the Ministry of Mines and Energy, through the National Department of Mineral Production (DNPM), through a Geographic Information System Mining (SIGMINE) with the information required in the processes required for mining exploration in Brazil. The Brazilian Institute of Geography and Statistics (IBGE) provides the variables and the Census 2000 and the Census Summary 2010, in addition with shapefiles with the spatial delimitation of population data at different levels of disaggregation. Between 1991 and 2000 Censuses, the mechanization of mining significantly reduced the number of workers employed in the sector. But the dynamics of "demographic bubble", rapid cycle of occupation and emptying of the areas associated with mining, is just one of possible relationships. In thy study area, the most populated and urbanized municipalities had a higher concentration of areas required for mining industry. In this case, the volume of ore and other minerals found and explored deposits were able to attract large investments to the region, however, they prioritized the creation of wealth rather than expanding access to basic sanitation services. The living conditions defined by the characteristics of household infrastructure revealed an extreme shortage of the population south of Pará / Mestrado / Demografia / Mestre em Demografia

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