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29-510: Kilo Moto is a semi-continuous greenstone belt in the northeast of the DRC. In the northern part, the Moto Goldmines project has an aggregate lease area of 1,841 square kilometres (711 sq mi), with most activity centered on a 35 square kilometres (14 sq mi) area around the old Durba gold mine. It is possible that as much as 25.7m ounces of gold are present. In the center

58-427: A detachment layer is present. Thrust tectonics is associated with the shortening and thickening of the crust, or the lithosphere. This type of tectonics is found at zones of continental collision , at restraining bends in strike-slip faults, and at the oceanward part of passive margin sequences where a detachment layer is present. Strike-slip tectonics is associated with the relative lateral movement of parts of

87-526: A greenstone belt and the granites they abut, and the Proterozoic where greenstone belts sit upon granite-gneiss basements and / or other greenstone belts, and the Phanerozoic where clear examples of island arc volcanism, arc sedimentation and ophiolite sequences become more dominant. This change in nature is interpreted as a response to the maturity of the plate tectonics processes throughout

116-831: A joint venture between AngloGold Ashanti and Randgold in the Kibali Gold Mine which the Randgold CEO has called the largest gold mine in Africa outside of South Africa. The partners had acquired the former owner Moto Gold Mines in October 2009. Greenstone belt Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gneiss bodies. The name comes from

145-528: A total recorded 11m ounces of gold from hard-rock mines in the Kilo Moto belt. Mining included a mixture of alluvials and shallow oxide pits. There were also underground industrial mines near Mongbwalu , namely Adidi , Senzere and Makala. The Democratic Republic of the Congo became independent in 1960 and the company was nationalised without compensation in 1967. As of 2011, Rio Tinto Mining and Exploration

174-413: Is associated with the stretching and thinning of the crust or the lithosphere . This type of tectonics is found at divergent plate boundaries, in continental rifts , during and after a period of continental collision caused by the lateral spreading of the thickened crust formed, at releasing bends in strike-slip faults , in back-arc basins , and on the continental end of passive margin sequences where

203-421: Is formed in the process of sea-floor spreading ; transform , where plates slide past each other, and convergent , where plates converge and lithosphere is "consumed" by the process of subduction . Convergent and transform boundaries are responsible for most of the world's major ( M w > 7) earthquakes . Convergent and divergent boundaries are also the site of most of the world's volcanoes , such as around

232-582: Is the Zani-Kodo area. To the south is the Mongbwalu field, a 10,000 square kilometres (3,900 sq mi) concession to the north and east of Bunia that is mainly owned by AngloGold Ashanti with the DRC parastatal Office des Mines de Kilo Moto (OKIMO) holding a 13.78% interest. The Kilo mine was opened in 1905 and the Moto mine in 1911. Gold was also extracted by panning the river gravels. In 1919

261-452: Is the study of the motions and deformations of the Earth's crust ( geological and geomorphological processes) that are current or recent in geological time . The term may also refer to the motions and deformations themselves. The corresponding time frame is referred to as the neotectonic period . Accordingly, the preceding time is referred to as palaeotectonic period . Tectonophysics is

290-496: The Archean greenstone belts. These similarities include a decrease in the amount of ultramafic and mafic rocks as you move up the stratigraphic column , in addition to an increase in pyroclastics , felsic and/or andesite rocks. Also, the rock successions tend to have clastics in the upper portion and tholeiitic suites in the lower. Calc-alkaline dikes are common in these suites. Archaean greenstones are found in

319-856: The Slave craton , northern Canada , Pilbara craton and Yilgarn Craton , Western Australia , Gawler Craton in South Australia , and in the Wyoming Craton in the US. Examples are found in South and Eastern Africa, namely the Kaapvaal craton and also in the cratonic core of Madagascar , as well as West Africa and Brazil , northern Scandinavia and the Kola Peninsula (see Baltic Shield ). Proterozoic greenstones occur sandwiched between

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348-586: The foreland to a collisional belt. In plate tectonics, the outermost part of the Earth known as the lithosphere (the crust and uppermost mantle ) act as a single mechanical layer. The lithosphere is divided into separate "plates" that move relative to each other on the underlying, relatively weak asthenosphere in a process ultimately driven by the continuous loss of heat from the Earth's interior. There are three main types of plate boundaries: divergent , where plates move apart from each other and new lithosphere

377-552: The Earth's geological history. Archaean plate tectonics did not take place on mature crust and as such the presence of thrust-in allochthonous greenstone belts is expected. By the Proterozoic, magmatism was occurring around cratons and with established sedimentary sources, with little recycling of the crust , allowing preservation of more sediments. By the Phanerozoic, extensive continental cover and lower heat flow from

406-519: The Earth's outer shell interact with each other. Principles of tectonics also provide a framework for understanding the earthquake and volcanic belts that directly affect much of the global population. Tectonic studies are important as guides for economic geologists searching for fossil fuels and ore deposits of metallic and nonmetallic resources. An understanding of tectonic principles can help geomorphologists to explain erosion patterns and other Earth-surface features. Extensional tectonics

435-466: The Pacific Ring of Fire . Most of the deformation in the lithosphere is related to the interaction between plates at or near plate boundaries. The latest studies, based on the integration of available geological data, and satellite imagery and Gravimetric and magnetic anomaly datasets have shown that the crust of the Earth is dissected by thousands of different types of tectonic elements which define

464-765: The Pilbara and Yilgarn cratons in Australia, and adjoining the Gawler Craton and within the extensive Proterozoic mobile belts of Australia, within West Africa, throughout the metamorphic complexes surrounding the Archaean core of Madagascar; the eastern United States , northern Canada and northern Scandinavia. The Abitibi greenstone belt in Ontario and Quebec is one of the largest Archean greenstone belts in

493-584: The characteristics of the Barberton Greenstone belt has been used as a primer for other greenstone belts around the world. He noted the existence of pillow lavas , indicating a lava being rapidly cooled in water , as well as the spinifex textures created by crystals formed under rapidly cooling environments, namely water. Tectonic Tectonics (from Latin tectonicus ; from Ancient Greek τεκτονικός ( tektonikós )  'pertaining to building ') are

522-419: The crust or the lithosphere. This type of tectonics is found along oceanic and continental transform faults which connect offset segments of mid-ocean ridges . Strike-slip tectonics also occurs at lateral offsets in extensional and thrust fault systems. In areas involved with plate collisions strike-slip deformation occurs in the over-riding plate in zones of oblique collision and accommodates deformation in

551-622: The government created the Régie Industrielle des Mines de Kilo-Moto , an autonomous body. In 1926 the Régie was converted into a commercial company, the Société des Mines d’Or de Kilo-Moto. Hydroelectric stations were built to power the crushing plants, and by 1930 the two mines, but mostly Kilo, were producing almost 5,000 kilograms (11,000 lb) annually. During the 1950s and 1960s Belgian charter companies extracted over 3m ounces from

580-535: The granite and gneiss events, because the vast majority of greenstones are interpreted as altered basalts and other volcanic or sedimentary rocks . As such, understanding the nature and origin of greenstone belts is the most fruitful way of studying Archaean geological history. Greenstone belts have been interpreted as having formed at ancient oceanic spreading centers and island arc terranes . Greenstone belts are primarily formed of volcanic rocks, dominated by basalt , with minor sedimentary rocks inter-leaving

609-406: The greater volume of otherwise homogeneous granite - gneiss within a craton contains a significantly larger degree of heterogeneity and complications and forms a tectonic marker far more distinct than the much more voluminous and homogeneous granites. Additionally, a greenstone belt contains far more information on tectonic and metamorphic events, deformations, and paleogeologic conditions than

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638-400: The green hue imparted by the colour of the metamorphic minerals within the mafic rocks: The typical green minerals are chlorite , actinolite , and other green amphiboles . Greenstone belts also often contain ore deposits of gold , silver , copper , zinc , and lead . A greenstone belt is typically several dozens to several thousand kilometres long. Typically, a greenstone belt within

667-431: The mantle has seen greater preservation of sediments and greater influence of continental masses. Greenstones, aside from containing basalts, also give rise to several types of metamorphic rocks which are used synonymously with ' metabasalt ' et cetera; greenschist , whiteschist and blueschist are all terms spawned from the study of greenstone belts. The West African early Proterozoic greenstone belts are similar to

696-404: The processes that result in the structure and properties of the Earth's crust and its evolution through time. The field of planetary tectonics extends the concept to other planets and moons. These processes include those of mountain-building , the growth and behavior of the strong, old cores of continents known as cratons , and the ways in which the relatively rigid plates that constitute

725-576: The study of the physical processes associated with deformation of the crust and mantle from the scale of individual mineral grains up to that of tectonic plates. Seismotectonics is the study of the relationship between earthquakes, active tectonics, and individual faults in a region. It seeks to understand which faults are responsible for seismic activity in an area by analysing a combination of regional tectonics, recent instrumentally recorded events, accounts of historical earthquakes, and geomorphological evidence. This information can then be used to quantify

754-403: The subdivision into numerous smaller microplates which have amalgamated into the larger Plates. Salt tectonics is concerned with the structural geometries and deformation processes associated with the presence of significant thicknesses of rock salt within a sequence of rocks. This is due both to the low density of salt, which does not increase with burial, and its low strength. Neotectonics

783-422: The volcanic formations. Through time, the degree of sediment contained within greenstone belts has risen, and the amount of ultramafic rock (either as layered intrusions or as volcanic komatiite ) has decreased. There is also a change in the structure and relationship of greenstone belts to their basements between the Archaean where there is little clear relationship, if any, between basalt- peridotite sheets of

812-802: The world. In Antarctica, the Proterozoic-aged Fisher Massif closely resembles the composition and structure of a greenstone belt. One of the best known greenstone belts in the world is the South African Barberton greenstone belt , where gold was first discovered in South Africa . The Barberton Greenstone belt was first uniquely identified by Prof Annhauser at the University of the Witwatersrand , Johannesburg . His work in mapping and detailing

841-412: Was in a joint venture with Kilo Goldmines, a Canadian company, to develop properties in the vicinity of Isiro and Mambasa . Kilo Goldmines was also active in a joint venture with Somituri sprl, a local company, in exploiting properties in the territories of Mambasa and Wamba near the village of Nia Nia . Colonial mines produced gold in this area from the 1920s until 1958. OKIMO held a 10% interest in

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