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The Karoo Supergroup outcropst in the mid-Zambezi Valley, southern Zambia. It is underlain by the Sinakumbe Group of Ordovician to Devonian age. The Lower Karoo Group (Late Carboniferous to Permian age) consists of the basal Siankondobo Sandstone Formation, which comprises three facies, overlain by the Gwembe Coal Formation with its economically important coal deposits, in turn overlain by the Madumabisa Mudstone Formation which consists of lacustrine mudstone, calcilutite, sandstone, and concretionary calcareous beds. The Upper Karoo Group (Triassic to Early Jurassic) is sub-divided into the coarsely arenaceous Escarpment Grit, overlain by the fining upwards Interbedded Sandstone and Mudstone, Red Sandstone; and Batoka Basalt Formations.Palynomorph assemblages suggest that the Siankondobo Sandstone Formation is Late Carboniferous (Gzhelian) to Early Permian (Asselian to Early Sakmarian) in age, the Gwembe Coal Formation Early Permian (Artinskian to Kungurian), the Madumabisa Mudstone Late Permian (Tatarian), and the Interbedded Sandstone and Mudstone Early or Middle Triassic (Late Scythian or Anisian). The marked quantitative variations in the assemblages are due partly to age differences, but they also reflect vegetational differences resulting from different paleoclimates and different facies.The low thermal maturity of the formations (Thermal Alteration Index 2) suggests that the rocks are oil prone. However, the general scarcity of amorphous kerogen, such as the alga Botryococcus sp., and the low proportion of exinous material, indicates a low potential for liquid hydrocarbons. Gas may have been generated, particularly in the coal seams of the Gwembe Coal Formation, that are more deeply buried.  相似文献   
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Mining in Zambia has been practised for centuries, and in the last 70 years Zambia has risen to become one of the world's leading Cu producers as a result of the exploitation of the Zambian Copperbelt orebodies. In contrast to this long history of mining, Zambia has a relatively short history of Earth Science Education. For the past 24 years, the earth sciences have been taught within the School of Mines in University of Zambia. The School started operation on 1st June, 1973, with the purpose of training professional geologists, extractive metallurgical/mineral processing engineers and mining engineers to service the needs of the mining industry in Zambia.The School consists of three departments — Geology, Metallurgy and Mineral Processing, and Mining Engineering — which deliver a five-year undergraduate programme. Students are admitted to the School after completing a one-year programme in the School of Natural Sciences of the University of Zambia. Students with an average of C+ or better in Biology, Chemistry, Mathematics and Physics are admitted into the School of Mines.The School of Mines has a total of 36 teaching positions — 12 for each Department. To successfully complete their course, students must pass 40 courses over a period of five years. During this time, industrial training is mandatory in the vacation periods after the third and fourth years of study. This training is mainly within the mining industry who in most cases sponsor the students for their studies in the School.The School admits 50 students on average per year, of whom five students take up Geology as a career. So far only two female students have studied in the School of Mines, both of them in Geology. The student to staff ratio in the Geology Department is 3 to 1. The low enrolment in Geology is thought to be because of a lack of knowledge of geology as a possible career by prospective students and a perceived lack of progression, once employed in industry. This has lead to a ‘Geoscience in Schools’ project with the main aim of making secondary school students aware of geology as a career.The Geology Department enjoys close co-operation with geology departments in a number of universities around the world, with industry, government ministries and regional bodies. It is hoped that the current increase in employment prospects for Geology graduates in Zambia will attract more students to geology as a career.  相似文献   
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Samples of topsoil together with reference samples of subsurface soil from a depth of 80–90 cm were collected in the central-northern part of the Zambian Copperbelt to distinguish lithogenic sources of metals from anthropogenic contamination of soils caused by fallout of dust from mining operations, flotation ore treatment plants, tailings dams, smelters and slag dumping grounds. The total sulphur, Cu and Co contents were found to be significantly higher in topsoil relative to subsurface soil over a large part of the surveyed area, and Zn, Pb, As and Hg contents showed a definite increase in the close neighbourhood of smelters and in the direction of prevailing winds. This indicates that the increase of these elements in the topsoil is due to anthropogenic activities. The areal extent and degree of anthropogenic contamination of topsoil can be expressed by an enrichment index (EI) based on the average ratio of the actual and median concentrations of the given contaminants. Although the contamination of soil by dust fallout decreases progressively with depth in the soil profile, in areas strongly affected by mining and mineral processing the anthropogenic contamination by sulphur and copper can be traced to a depth of 80–90 cm. In contrast, the concentration of elements such as Cr, Ni, and V, that show a direct correlation with the content of iron in the soils, increases in the subsurface soil relative to the topsoil. This is particularly evident in areas underlain by rocks of the Katanga Supergroup.  相似文献   
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