Bushveld igneous complex archives state of the planet. The bushveld layered complex of south africa measures up to 100. South africa is the worlds top producer of platinum, used in everything from jewelry to catalytic converters. Multivariate geochemical classification of chromitite. The palaeoproterozoic bushveld complex has been studied in detail in the last century, primarily because of the richness of the ore deposits of platinum. The general aquifer model for the bushveld complex comprises a perched, shallow aquifer in the weathered zone. Bushveld complex article about bushveld complex by the free. The bushveld complex is located in south africa, between the limpopo and north west provinces and covers an area of approximately 66000 km2 it consists of four groups of rocks.
The bushveld complex is a 65,000 km2 layered intrusive. The platinum group element deposits of the bushveld. Geochemistry of magnetitite layers in the upper zone of. Bushveld complex deposits of platinum and chromites, situated in transvaal province of the republic of south africa, on the territory of the districts of. Geochemistry of magnetitite layers in the upper zone of the bushveld complex, south africa. Access the pdf merger from any internetconnected desktop or mobile device and. Novel hypothesis for origin of massive chromitites in the. The geological setting, composition, mineralogy, and textures of the ores are described for the bushveld and stillwater complexes, the great dyke, the munni munni intrusion, complexes in finland, and some smaller intrusions. Kinnaird and mcdonald mineralisation in the northern limb of the bushveld complex 1 geological map of the northern limb of the bushveld complex showing the principal locations mentioned in the text. It is approximately 2 billion years old and is divided into four different limbs. Map of western and eastern limbs of the bushveld complex, south africa, showing outcrop trace of the ug2 chromitite and surface projection of mineral resource. It shows part of the bushveld complex, an area around the bospoort dam. The maficultramafic intrusion is up to 750 m thick and hosts large quantities of basemetal sulfides containing.
Platinumgroup elements in southern africamineral inventory. Oct 19, 2012 platinumgroup element pge deposits in the bushveld complex and other layered intrusions form when large, incompletely solidified magma chambers undergo central subsidence in response to crustal loading, resulting in slumping of semiconsolidated cumulate slurries to the centres of the intrusions and hydrodynamic unmixing of the slurries to form dense layers enriched in sulfides, oxides. Bushveld minerals acquisition of bushveld vametco limited. Shear wave velocity structure of the bushveld complex, south africa eldridge m. It lies almost entirely within the bounds of the transvaal. On the relationship between the bushveld complex and its. Bushveld igneous complex article about bushveld igneous. The bushveld igneous complex bic is the largest layered igneous intrusion within the earths crust. The bushveld complex, as exposed at cur rent levels of erosion, consists eastern, western and northern limbs, see figure 1, and is some. The bushveld complex, a product of interaction among magmas. Platinumgroup elements in the upper zone of the rustenburg layered suite of the bushveld complex.
Pdf the bushveld complex is wellknown for its large proportion of the worlds platinum and palladium resources. Powerful, fast, and optimized for all phones and tablets, xodos mobile app makes it easy to access, mark up, sort, share, sync, and manage even the most complex pdf documents. Geochemistry and mineralogy of the platreef and critical. Low cost means targeting the lowest cost position on the vanadium production cash cost curve, leveraging the high insitu and inmagnetite v 2 0 5 grades and the opencast mining proposition of bushveld minerals. They are characterized by a raised ferriferousness of the chrome spinels. Bushveld complex geological formation, south africa. This paper reports on the composition of chromite in the critical zone of the central sector of the eastern complex, as. The bushveld complex in the context of thethe bushveld.
The deposit is located 50 km east of the eastern limb of the bushveld complex and measures about 10 km by 800 m. A geological map of the area, which provides the largest known example of this interesting type of formation, is shown on the facing page. The american geosciences institute represents and serves the geoscience community by providing collaborative leadership and. Hatton anglo american research laboratories pty ltd. Webb c a council for geoscience, 280 pretoria road, private bag x112, pretoria 0001, south africa. Complex and they seem to merge with the major seams. Construction expos in south africa recommended for you. The bushveld complex is the largest maficultramafic layered intrusion on earth and encompasses about a million cubic kilometres of igneous rocks that were emplaced into the upper crust 205 billion years ago as part of a major intracontinental magmatic event. A primary vanadium platform means having one of largest highgrade primary vanadium resource base and the largest primary vanadium production in the world. Nov 17, 2007 a new geological map of the rustenburg layered suite south of the ysterbergplanknek fault of the northernpotgietersrus limb of the bushveld complex is presented, displaying features that were not available for publication in the past and are considered contributing to the complexity of this region. Kinloch amplats research centre, po box 6540, homestead, 1412, south africa and c.
Where the reef is thick, the platinum values are confined to its uppermost portion. The bushveld complex, a product of interaction among magmas derived from a mantle plume c. The bushveld complex is composed of the principle eastern, western, and northern limbs along with a number of outliers. The complex includes the merensky reef, which is the worlds biggest source of platinum as well as platinumgroup metals. Simplified geologic map and cross section of the bushveld complex. A new geological map of the rustenburg layered suite south of the ysterbergplanknek fault of the northernpotgietersrus limb of the bushveld complex is presented, displaying features that were not available for publication in the past and are considered contributing to the complexity of this region. The economic potential of many ore deposits is difficult to evaluate,but this is not so in the case of the bushveld ores. Origin of anorthosite and magnetitite layers in the bushveld.
An intrusive origin of some ug1 chromitite layers in the. Origin of anorthosite and magnetitite layers in the. The great dyke and the bushveld complex molope farms complex intruded preexisting crustal structures which transected the whole of the zimbabwe and kaapvaal cratons respectively convergent tectonic settings at highoblique angles to these structures would have created high dilation and slip tendencies on these structures. The chromium deposits of the bushveld complex, the potential resources of which are estimated at 2 billion tons, are found in pseudostrata, persistent for considerable distances, of ingrained and massif ores, 2 cm to 2 m thick in the pyroxenites and anorthosites. The bushveld complex the bushveld complex is the worlds largest layered intrusion, and because of its unique char acter most other layered intrusions are compared with it. The geology of the bushveld complex before discussing how these estimates are calculated, it is worth considering the origins and geology of the bushveld complex. Pdf mercury distribution amongst coexisting silicates. Possibly the most important omission in many of these subsequent contributions is the recognition about the distribution of the mineralization, summarized by wagner 1929. Due to the enormous size of the bushveld, the roof of the intrusion is neither eve. Geochemistry and mineralogy of the platreef and critical zone of the northern lobe of the bushveld complex, south africa. Pmas 100% owned tenements cover areas of one of the worlds largest known layered mafic intrusions, the windimurra complex, which is a close model of south africas mineralrich bushveld igneous complex bic, the worlds dominant source of platinum group metals pgm. Lee amplats geological services, po box 62179, marshalltown, johannesburg, 2107, south africa.
Platinumgroup elements in southern africamineral inventory and. The bushveld complex has been cited 1, 2, as a possible example of a large diameter 400 km, volume 10 6 km 3 igneous province generated by rapid decompression melting at the leading edge of a mantle plume, triggered by the impact of a large d. Bushveld definition is veld of southern africa with abundant shrubby and often thorny vegetation. There are three very different ore bodies, the merensky reef, the upper group 2 ug2. An introduction to mineralisation in the northern limb of. The 2060 ma old bushveld complex of about 66000 km2 extent is a saucershaped layered igneous intrusion and one of the great geological wonders of the world.
The bushveld complex, a layered mafic intrusion in south africa, shows extreme vertical differentiation in terms of mineral. For best results viewing and printing pdf documents, it is recommended that you download the documents to your computer and open them with adobe reader. The zonal nomenclature of the bushveld complex relegated to informal status by the south african committee for stratigraphy 1980, is reinstated and redefined using a hierarchy of zones, subzones. Thirty separates of plagioclase, orthopyroxene and clinopyroxene from the lower main zone of the northern limb of the bushveld complex were analysed for their mercury contents using combustion atomic absorption spectroscopy with gold amalgamation. Most of it comes from a geological formation the size of west virginia, called the bushveld igneous complex, created two billion years ago as molten lava from earths mantle bubbled to the surface and cooled. The bushveld complex underlies an area of about 50,000 square km 20,000 square miles. Pdf the platinum and palladium resources of the bushveld. It contains many magmatic ores, pegmatitic and hydrothermal ore deposits and has metamorphosed the floor rocks of the intrusive. Pdf documents opened from your browser may not display or print as intended. Geological interpretations from the pge distribution in. Pdf the platinum and palladium resources of the bushveld complex.
The ug1 chromitite in the bushveld complex is a 1 m thick massive layer overlain by orthopyroxenite 49 m thick and underlain by anorthosite 1. The bushveld complex, the largest layered maficultramafic intrusion worldwide, is host of numerous, laterally continuous and chemically similar chromitite layers. Bushveld complex bc 300km east west synclinal basin containing vast quantities of pgms and chromite. Pdf virgin rock temperatures and geothermal gradients in. Xodo is the ultimate crossplatform pdf viewer and annotator. The bushveld complex see figure 2 is an enormous irruption. Based on their stratigraphic position the layers are subdivided into a lower, middle and. Clarkmostert twp projects the presence of geological structures in igneous complexes such as the bushveld complex in south africa and the great dyke in zimbabwe is to be expected. The complex is made up of ultramafic to felsic igneous rocks and formed by repeated injection of magma into an enormous chamber. Geology and geomorphology of a uniquely layered ultramaficmafic intrusion pdf version geoscience in the economy.
Pge enrichment in chromitite layers and the merensky reef of the western bushveld complex. Pdf pge enrichment in chromitite layers and the merensky. Platinumgroup elements in the upper zone of the rustenburg. Geology 314 accretion of the bushveld complex foreword. The origin of chromitites in the bushveld complex has been attributed to two principal. Eastern limb of the bushveld complex, south africa. Chromite in the central sector of the eastern bushveld. From east to west, the bushveld extends over 350 km, and the eastern limb alone crops out for more than 150km northsouth. A dissertation submitted to the school of geosciences, university of the witwatersrand, johannesburg, south africa in fulfilment of the requirements for the degree of. The bushveld complex is wellknown for its large proportion of the worlds platinum and palladium resources. High underground temperatures reduce labour productivity, the highest cost element of mining. This is the preface to a special issue on various aspects of the bushveld complex, transvaal basin, south africa. A generalized map and various stratigraphic sections through the bushveld complex are shown in figs 1 and 2.
Bushveld minerals is a lowcost, vertically integrated primary vanadium producer with a diversi. Darker layers originally more clayrich, paler layers originally of silt or fine sand. In this study we focus on the majorelement concentrations in plagioclase analysed from a 28 km deep borehole core drilled through the upper part of the bushveld complex, south africa ashwal et al. Is there some commonality between the geological structures in the bushveld complex and the great dyke. Inventory and an assessment of undiscovered mineral resources u. Toronto stock exchange manual, national instrument 43101. Shear wave velocity structure of the bushveld complex, south.
Tectonic controls on the great dyke and the bushveld complex. Map of western and eastern limbs of the bushveld complex, south. Pdf despite a plethora of petrological studies, the emplacement mechanics of the worlds largest layered intrusion, the 2. Both chromite and associated silicates in chromiterich and chromitepoor rocks have been studied. To accomplish more complex tasks, you need to install additional software. Platinumgroup element pge deposits in the bushveld complex and other layered intrusions form when large, incompletely solidified magma chambers undergo central subsidence in response to crustal loading, resulting in slumping of semiconsolidated cumulate slurries to the centres of the intrusions and hydrodynamic unmixing of the slurries to form dense layers. The northern limb is known for the platreef, atypical mafic lithologies in sections of the. Combining this model of crystal growth with natural temperature cycling in magma chambers 73 indicates that temperature cycles of only a few.
After willemse 1964, wager and brown 1968, and irvine et al. The geology is described briefly assuming familiarity on the part of the reader. Geology and geomorphology of a uniquely layered ultramaficmafic intrusion. The uitkomst complex has been suggested to be genetically related to the 2060 ma, bushveld igneous complex bic. Drive back to johannesburg via middleburg and emalahleni. Banding exists on several scales, and is preserved down to submillimetre scale. The zonal nomenclature of the bushveld complex relegated to informal status by the south african committee for stratigraphy 1980, is reinstated and redefined using a.
It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin. Part or all of this report is presented in portable document format pdf. Novel hypothesis for origin of massive chromitites in the bushveld. Geological interpretations from the pge distribution in the bushveld. Introduction to the bushveld complex, south africa the bushveld complex, of palaeoproterozoic age, is located in the central northeast portion of the kaapvaal craton in southern africa, and has an estimated total area of 65 000 km2 hunter, 1976. Geologic map of the bushveld complex and surrounding rocks, south africa. The merensky cyclic unit, bushveld complex, south africa. Ensure data cells are associated with the correct header cells. Pdf structural and compositional constraints on the emplacement. Apr 11, 20 5 years to complete sinking the shafts at the new bakubung platinum mine big construction project duration. The bushveld complex, a product of interaction among.
Higher underground thermal gradient than the goldbearing witwatersrand basin, requiring refrigeration for underground mines deeper than 700 metres. Box 106, crown mines, 2025, south africa chromite and pgeenriched layers in the bushveld are modelled on a process of the cooling of resident lower zone magma by sub. Geological setting university of the witwatersrand. As most of the region tends to be dry, the bushveld is mostly beef cattle and game farming country, with only a few droughtresistant crops such as sorghum and millet being farmed, usually under irrigation. Many thin layers of chromitite exist in the bushveld. To look for the presence of merged or split cells, visually inspect the document. The bushveld also supplies significant quantities of palladium, rhodium, chromium, and vanadium. Zamani addmore dube 0303958g thesis submitted to the faculty of science, university of the witwatersrand johannesburg in. Bushveld complex bc sedibelo platinum mines limited.
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