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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.
71

The petrogenesis of the Koperberg suite in the jubilee mine, Namaqualand.

Van Zwieten, Adrianus Josephus Maria January 1996 (has links)
Thesis submitted for the degree MAGISTER SCIENTIAE to the Faculty of Science, Department of Geology, University of the Witwatersrand, Johannesburg / The Koperberg Suite intrusion at Jubilee, Namaqualand varies in composition from anorthosite, through mica diorite to pyroxene leucodiorite and pyroxene diorite. Detailed mapping and petrological studies of these rocks indicate that they were sequentially emplaced into the Concordia Granite country rocks, and that each of the rock types represent discrete magmatic events. The sequence of intrusion is from more acidic to more basic. Whole-rock geochemical analyses indicate that these rocks represent cumulates involving variable proportions of plagioclase, orthopyroxene, mica, quartz, oxides and immiscible sulphides. These cumulate phases intruded into the Concordia Granite at the time of peak of metamorphism and deformation in the Okiep Copper District, i.e, about 1030Ma ago, At the time of intrusion, the country rocks were under going partial melting under high grade (granulite facies) metamorphic conditions. and granitic anatects were present in the crust. Hybridisation of basic magma and granitic melts occurred within the shear zones along which the basic magmas ascended. The En content of orthopyroxene in the Koperberg Suite exceeds the An content of plagioclase. This is atypical of basic intrusions and is a consequence of this mixing. Mixing calculations based on the initial 87Sr/86Srratio (Ru) of the Jubilee samples at 1030Ma, imply high levels of assimilation (as much as 80% assimilation in the case of anorthositic rocks) between a granitic component, similar in composition to the Nababeep Gneiss and a mantle-derived basic magma. Sulphide mineralisation was initiated by the assimilation process, which caused the separation of immiscible sulphides from the hybridised magma. Subsequent oxidation of the original sulphide assemblage produced bornite, chalcopyrite and Ti-poor magnetite. / Andrew Chakane 2019
72

Mining and smelting technology and the politics of bronze in Shang and Western Zhou China : an inquiry into the Bronze Age interaction sphere

Reinhardt, Katrinka. January 1997 (has links)
In this thesis I focus on mining and smelting in China during the Shang and Western Zhou periods (c. 2200-770 B.C.). The importance of bronze in Shang and Zhou society and the vast quantity of bronze artifacts recovered indicates that the acquisition of metal ore would have been a major occupation of the state. The Shang and Zhou governments controlled their own bronze foundries but did not control the mines. The mines are located in southern China where the Chu state flourished during the Eastern Zhou period, likely due partly to their possession of mineral resources, and in Inner Mongolia where the steppe cultures existed. The Zhou and the Shang were likely obtaining raw materials from southern and northern cultures, either through trade or raid. Provenance studies based on chemical composition of artifact and ore will help resolve the source of Shang and Zhou ore.
73

Structural geology, metamorphism and origin of the Kanmantoo Copper deposit, South Australia / by Jeffrey Christopher Schiller.

Schiller, Jeffrey Christopher January 2000 (has links)
Appendices 5 and 6 are made available in CD-ROM format. / Includes copies of articles co-authored by the author during the preparation of this thesis as appendix 7. / 14 maps (some folded, some col.); inserted in back pocket. / Includes bibliographical references (leaves 242-264). / System requirements for accompanying CD-ROM: Macintosh of IBM compatible computer. Other requirements: Adobe Acrobat Reader. / [15], 264 leaves : ill. (some col.), maps ; 30 cm. + 1 computer optical disk (4 3/4 in.) / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / On the basis of the present study it is concluded that there is no firm evidence that the bulk of the mineralisation is pre-metamorphic, although the possibility has not been excluded. / Thesis (Ph.D.)--Adelaide University, Dept. of Geology and Geophysics, 2001
74

Structural geology, metamorphism and origin of the Kanmantoo Copper deposit, South Australia / by Jeffrey Christopher Schiller.

Schiller, Jeffrey Christopher January 2000 (has links)
Appendices 5 and 6 are made available in CD-ROM format. / Includes copies of articles co-authored by the author during the preparation of this thesis as appendix 7. / 14 maps (some folded, some col.); inserted in back pocket. / Includes bibliographical references (leaves 242-264). / System requirements for accompanying CD-ROM: Macintosh of IBM compatible computer. Other requirements: Adobe Acrobat Reader. / [15], 264 leaves : ill. (some col.), maps ; 30 cm. + 1 computer optical disk (4 3/4 in.) / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / On the basis of the present study it is concluded that there is no firm evidence that the bulk of the mineralisation is pre-metamorphic, although the possibility has not been excluded. / Thesis (Ph.D.)--Adelaide University, Dept. of Geology and Geophysics, 2001
75

The environmental and social history of the O'Donnell roast yard and townsite near Sudbury, Ontario

Symington Sager, M. Sheena January 1999 (has links) (PDF)
No description available.
76

The Kansanshi Cu-Au deposit, Domes region, Zambia : geology, mineralisation and alteration characteristics in the main pit

Chinyuku, Donald Tichaona January 2014 (has links)
The Kansanshi Cu-Au deposit located in the Domes region of the North West province of Zambia is characterised by structurally controlled high angle veins and associated alteration halos. The northwest trending Kansanshi antiform flanks the Solwezi syncline to the north and hosts the Kansanshi deposit and consists of tillites and metasedimentary rocks. Mineralisation is associated with Neoproterozoic Pan African deformation events experienced during the formation of the Lufilian fold belt; however recent findings confirm that structures in the form of reverse and normal faults and drag folds are critical controls on mineralisation within the deposit, Main pit in particular. Low angle faults occurring below the current pit are believed to have served as major fluid pathways during mineralisation. Age dating data from the Kansanshi deposit suggest that mineralisation took place between 512 and 503 Ma indicating that the event was associated with metamorphism. Two types of alteration are dominant within the Main pit (Kansanshi deposit) with the type and intensity of alteration being largely controlled by lithological units. Albite alteration occurs dominantly in phyllites and schists whereas dolomitisation is prevalent in calcareous units. Alteration is associated with mineralisation, and therefore is used as a condition for predicting vein or disseminated mineralisation. The high Au tenor at Kansanshi can be attributed to gold grains occurring in association with melonite (NiTe₂) and microfractured pyrite intergrown with chalcopyrite in sulphide and quartz dominated veins and veinlets. Analysis of gold grade distribution within the Main pit shows a clear concentration of the element along the major north-south trending structures like the 4800 and 5400 zones, possibly through supergene enrichment in the oxide-transition-sulphide zones. It is imperative that exploration for Kansanshi-type deposits will require geochemical and geophysical studies, understanding of the geology of an area to identify the three lithostratigraphic units (red beds, evaporites and reducing strata).
77

The geology of the Shamrocke Mine and surrounding area, Rhodesia

Kyle, Derek Lyndon January 1972 (has links)
The geology of the Shamrocke area is described relative to its regional setting and position within the stratigraphic succession of the Lomagundi System. The stratigraphy in the immediate vicinity of the Shamrocke Mine is detailed and discussed relative to the work of others south of the project area and in other regions. The petrography of the rocks of the Shamrocke Mine area is described and the results of a great deal of mineralogical work recorded. Maps of the project area are presented at various scales from field and photogeological evidence. The thesis area is situated on the South Zambezi Escarpment of Rhodesia, and the geology described included the basaI succession of the Lomagundi System and the pre-Lomagundi Escarpment Series. The Shamrocke Mine is located on a copper orebody associated with a granulite or granofels zone within the Dolomite Series of the Lomagundi System. This ore zone granulite appears to be a metasomatised calcareous grit some 1000 feet above the upper contact of the Deweras Series (basal Lomagundi) and, within the graphitic schist and phyllite, below a dolomitic horizon in the Dolomite Series. The Lomagundi succession in the Mine area unconformably overlies the pre-Lomagundi gneiss and meta-arkose of the older, metamorphosed and deformed Escarpment Series. The basal meta-arkose, meta-quartzite and coarse schist of the Deweras Series ascends southwards through the Dolomite Series (graphitic phyllite and schist, granulite, calcareous grit, dolomite, limestone), and the Argillaceous Series (schist, phyllite, quartzite), the beds dipping steeply to the south at an angle of between 50º and 70º. Post-Lomagundi plagioclase amphibolite (altered, intrusive meta-diabase) forms Iarge semi-concordant and transgressive sills throughout the area, particularly along the contact between the Deweras and Dolomite Series. The Shamrocke Mine is on the northern limb of a large synclinal structure, the Rusere Syncline, which forms a large embayment of Lomagundi rocks into the pre-Lomagundi gneisses and granodiorites northeast from the Mine. The fold is overturned to the east and southeast. The copper mineralisation within the area and in the areas to the south is considered to be invariably associated with the basal rocks of the Lomagundi System. It occurs within both the Deweras and Dolomite Series rocks and more often than not Iies close to the contact between these two Series. The sulphide mineralisation of the Shamrocke orebody is considered, from the results of the present study, to be metasomatically emplaced during carbonate metasomatism, either from an extraneous source or from within the ore zone rock itself. The present writer favours the origin of the copper sulphide to be original syngenetic sulphide of the basal rocks of the Lomagundi depository, which has been mobilised and metasomatically relocated, possibly by the effects of regional metamorphism related to intense deformation. It is perhaps not fortuitous that the majority of the copper occurrences in the area occur where the basaI beds of the succession have been cross-folded. The copper ore comprises a simple suite of minerals, the main constituents being chalcopyrite, cubanite and pyrrhotite. The deposit is compared relative to the other copper deposits of the Lomagundi System.
78

Towards social impact assessment of copper-nickel mining in Botswana

Mengwe, Moses Seargent January 2010 (has links)
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.
79

Mining and smelting technology and the politics of bronze in Shang and Western Zhou China : an inquiry into the Bronze Age interaction sphere

Reinhardt, Katrinka. January 1997 (has links)
No description available.
80

An assessment of heavy metal pollution near an old copper mine dump in Musina, South Africa

Singo, Ndinannyi Kenneth 24 October 2013 (has links)
Heavy metal pollution in water and soil is a serious concern to human health and the associated environment. Some heavy metals have bio-importance but the bio-toxic effects of many of them in human health are of great concern. Hence, there was a need for proper understanding of the concentration levels of these heavy metals in ground water and soil around the community residing in the vicinity of the defunct mine. Mining has become prominent in this area because of the existence of copper lodes, veins and veinlets. It was therefore necessary to assess these selected metals associated with copper mining as their concentration has a tendency to affect the environment and human health. The objective of this study was to establish the levels of lead (Pb)-zinc (Zn)-copper (Cu)-arsenic (As)-nickel (Ni) metals in ground water and soil associated with an old copper mine in the vicinity of the township and to compare them with the South African and international standards in order to safeguard the health of the community using such water for drinking purpose. Clean sampling plastic bottles were used to collect water from five water boreholes being used at present. Water samples were filtered using membrane filtration set LCW (0.45 μm). The samples were digested sequentially with different procedures for the total metal concentration. Concentrations of four metals commonly associated with Cu mining were examined at five different water boreholes which are used for drinking and industrial purposes. Flame Atomic Absorption Spectrophotometer (Perkin Elmar S/n 000003F6067A, Singapore) was used to analyze metals in water samples at Eskom Ga-Nala Laboratory: pH, electrical conductivity and turbidity were analyzed using an auto titrator meter (AT- 500,Japan), conductivity meter (Cole-parmer® YO-19601-00) and turbidity meter (AL 250TIR, Agua lytic, German) respectively. Soil samples were collected from the selected areas where human health is of a serious concern, and a hand held auger drill was used to recover samples, while shovels were used to prepare the sampling area. The samples were sieved up to 63.0 μm particle size and digested with aqua-regia. Flame Atomic Absorption Spectrophotometer (Model: AA400; Year: 2008; Manufacturer: Perkin Elmer; Germany; Serial no: 201S6101210) was used at the University of Venda Laboratory to analyze soil from the study area for possible heavy metal contamination due to the defunct Cu mine in the area. v The results showed variation of the investigated parameters in water samples as follows: pH, 6.0 to 7.51; EC, 70.0 to 96.40 μS/cm and turbidity, 1.05 to 4.56 NTU. The mean concentration of the metals increased in the followed order: Pb<Cu<As<Ni. Ni is the most abundant in the ground water determined with value of (6.49 μg/g). The observations have confirmed that most ground water contains an appreciable quantity of Ni. The mean value of As in water is (4.20 to 4.84 μg/g), Pb and Cu have (2.13 to 2.58 μg/g) and (1.52 to 2.52 μg/g) respectively. For soil samples, the mean concentration of the metals increased in the following order: Pb<Cu<Zn<As<Ni. Pb ranged from (0.023 to 0.036 μg/g) followed by Cu (0.28 to 0.45 μg/g) then Zn (0.026 to 0.053 μg/g), the mean range of As in soil ranged from (0.054 to 0.086 μg/g). However, some studies show much higher contamination of As from the natural sources and Ni with (0.057 to 0.144 μg/g) lastly. Accumulation of heavy metals in soil is of concern due to their toxic effects on human and animals. The quality of ground water from the five boreholes studied was satisfactory with turbidity (T), electrical conductivity (EC) and heavy metals (HM’s) below the WHO limit. The water therefore may, according to the WHO Standards be safely used as a drinking water. The concern lies on pH which was slightly (0.5) below the standard. There is a serious need to monitor the ground water which is now used for drinking purposes. This study revealed that heavy metal pollution in soil from the abandoned Cu mine in Musina is a threat to the health of the community. Although pollution was between medium and low in the contamination index, it is therefore important for the Musina Municipality or mine owner of Musina (TVL) Development Co Ltd copper mine to advocate possible remedial actions which will safeguard the environment and human health. The tailing at Musina’s old Cu mine have high pH and they lack normal soil stabilization processes, as a result the tailing does not develop a good plant cover. Pollution of the ground water resources is also evident in the study area where there is seepage or ingress of polluted water to the underground aquifers. Small-scale mining in Musina is causing further degradation to the environment but it supports the South African Waste Hierarchy by promoting the reuse and recycling of the tailing and mine dumps for the production of bricks. Mine workers are exposed to the above mentioned toxic heavy metals daily. Medicine will not help stop the poisoning. The only way to stop the metal poisoning is to stop being exposed to the heavy metals. / Environmental Sciences / M. Sc. (Environmental Management)

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