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Geology Of South Africa
The geology of South Africa is highly varied including cratons, greenstone belts, large impact craters as well as orogenic belts. The geology of the country is the base for a large mining sector that extracts gold, diamonds, iron and coal from world-class deposits. The geomorphology of South Africa consists of a high plateau rimmed to west, south and southeast by the Great Escarpment, and the rugged mountains of the Cape Fold Belt. Beyond this there is strip of narrow coastal plain. Cratons and orogens The basement of much of the northeastern part of South Africa is made up by the Kaapvaal craton. To the south and east, the craton is bordered by the Namaqua-Natal belt. In Neoproterozoic times, much of South Africa stabilized into the large Kalahari Craton that came to form part of the supercontinent Rodinia. The Kalahari Craton was near the center of Rodinia with paleogeographic reconstructions indicating it was surrounded by the cratons of Laurentia, Río de la Plata, Congo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brazilian Highlands
The Brazilian Highlands or Brazilian Plateau () is an extensive geographical region covering most of the eastern, southern and central portions of Brazil, in all some 4,500,000 km2 (1,930,511 sq mi) or approximately half of the country's land area. The vast majority of Brazil's population (203.062.512; ''2022 census'') lives in the highlands or on the narrow coastal region immediately adjacent to it. Ancient basaltic lava flows gave birth to much of the region. However, the time of dramatic geophysical activity is long past, as there is now no seismic or volcanic activity. Erosion has also played a large part in shaping the Highlands, forming extensive sedimentary deposits and wearing down the mountains. The Brazilian Highlands are recognized for its great diversity: within the region there are several different biomes, vastly different climatic conditions, many types of soil, and thousands of animal and plant species. Major divisions Due to its size and diversity, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastern Greenland
Tunu, in Danish Østgrønland ("East Greenland"), was one of the three counties (''amter'') of Greenland until 31 December 2008. The county seat A county seat is an administrative center, seat of government, or capital city of a county or parish (administrative division), civil parish. The term is in use in five countries: Canada, China, Hungary, Romania, and the United States. An equiva ... was at the main settlement, Tasiilaq. The county's population in 2005 was around 3,800. The county was made up of two former municipalities, Ammassalik Municipality and Ittoqqortoormiit Municipality. In 1974, the Northeast Greenland National Park was created from the vast and virtually uninhabited northern part of Illoqqortoormiut Municipality. It then covered the northern half of the county. Tunu was bordered in the east by the Greenland Sea, Denmark Strait and the North Atlantic Ocean. To the west lies Kitaa, and to the north, Avannaa. In 1988, the National Park was enlarged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epeirogenic Movement
In geology, epeirogenic movement (from Greek ''epeiros'', land, and ''genesis'', birth) is upheavals or depressions of land exhibiting long wavelengths and little folding apart from broad undulations. The broad central parts of continents are called cratons, and are subject to epeirogeny. The movement may be one of subsidence toward, or of uplift from, the center of Earth. The movement is caused by a set of forces acting along an Earth radius, such as those contributing to isostasy and faulting in the lithosphere. Epeirogenic movement can be permanent or transient. Transient uplift can occur over a thermal anomaly due to convecting anomalously hot mantle, and disappears when convection wanes. Permanent uplift can occur when igneous material is injected into the crust, and circular or elliptical structural uplift (that is, without folding) over a large radius (tens to thousands of km) is one characteristic of a mantle plume. In contrast to epeirogenic movement, orog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rift
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side. Where rifts remain above sea level they form a rift valley, which may be filled by water forming a rift lake. The axis of the rift area may contain volcanic rocks, and active volcanism is a part of many, but not all, active rift systems. Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates. ''Failed rifts'' are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Antarctica
East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctic continent, lying primarily in the Eastern Hemisphere south of the Indian Ocean, and separated from West Antarctica by the Transantarctic Mountains. It is generally greater in elevation than West Antarctica, and includes the Gamburtsev Mountain Range in the center. The geographic South Pole is located within East Antarctica. Apart from small areas of the coast, East Antarctica is permanently covered by ice and it has relatively low biodiversity, with only a small number of species of terrestrial plants, animals, algae, and lichens. The coasts are the breeding ground for various seabirds and penguins, and the leopard seal, Weddell seal, elephant seal, crabeater seal and Ross seal breed on the surrounding pack ice in summer. Location and description Almost completely covered in thick, permanent ice, East Antarctica comprises Coats Land, Queen Maud Land, Enderby Land, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precambrian Research
''Precambrian Research'' is a peer-reviewed scientific journal covering the geology of the Earth and its planetary neighbors. It is published by Elsevier and, , the editor-in-chief is V. Pease (Stockholm University). It was established in 1974. According to the ''Journal Citation Reports'', the journal has a 2022 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 3.8. References External links * Geology journals Elsevier academic journals English-language journals Academic journals established in 1974 {{geology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dronning Maud Land
Queen Maud Land () is a roughly region of Antarctica claimed by Norway as a dependent territory. It borders the claimed British Antarctic Territory 20° west, specifically the Caird Coast, Coats Land on the West, and the Australian Antarctic Territory 45° east, specifically Enderby Land on the East. In addition, a small unclaimed area from 1939 was annexed in June 2015. Positioned in East Antarctica, it makes out about one-fifth of the continent, and is named after the Norwegian Queen Maud (1869–1938). In 1930, the Norwegian Hjalmar Riiser-Larsen was the first person known to have set foot in the territory. On 14 January 1939, the territory was claimed by Norway. On 23 June 1961, Queen Maud Land became part of the Antarctic Treaty System, making it a demilitarised zone. It is one of two Antarctic claims made by Norway, the other being Peter I Island. They are administered by the Polar Affairs Department of the Norwegian Ministry of Justice and Public Security in Osl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congo Craton
The Congo Craton, covered by the Palaeozoic-to-recent Congo Basin, is an ancient Precambrian craton that with four others (the Kaapvaal, Zimbabwe, Tanzania, and West African cratons) makes up the modern continent of Africa. These cratons were formed between about 3.6 and 2.0 billion years ago and have been tectonically stable since that time. All of these cratons are bounded by younger fold belts formed between 2.0 billion and 300 million years ago. The Congo Craton occupies a large part of central southern Africa, extending from the Kasai region of the DRC into Sudan and Angola. It forms parts of the countries of Gabon, Cameroon, and the Central African Republic. A small portion extends into Zambia as well, where it is called the Bangweulu Block. Congo–São Francisco The Congo Craton and the São Francisco Craton are stable Archaean blocks that formed a coherent landmass until the opening of the South Atlantic Ocean during the break-up of Gondwana ( 2000–130 Ma). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Río De La Plata Craton
The Rio de la Plata Craton (RPC) is a medium-sized continental block found in Uruguay, eastern Argentina and southern Brazil. During its complex and protracted history it interacted with a series other blocks and is therefore considered important for the understanding of the amalgamation of West Gondwana. Two orogenic cycles have been identified in the RPC: a 2000 Ma-old western domain representing the old craton and a 700–500 Ma-old eastern domain assigned to the Brasiliano Cycle. It is one of the five cratons (ancient nuclei) of the South American continent. The other four cratons are: Amazonia, São Francisco, Río Apa and Arequipa–Antofalla. Geology Three shear zones divides the Precambrian basement of Uruguay and southern Brazil into four terranes. Along the Uruguayan east coast (reaching into Brazil) is the Cuchilla Dionisio Terrane, an allochthonous African block juxtaposed to the RPC along the Sierra Ballena Shear Zone (SBSZ). West of Cuchilla D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laurentia
Laurentia or the North American craton is a large continental craton that forms the Geology of North America, ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and the Hebridean terrane in northwest Scotland. During other times in its past, Laurentia has been part of larger continents and supercontinents and consists of many smaller terranes assembled on a network of early Proterozoic Orogenic belt, orogenic belts. Small microcontinents and oceanic islands collided with and Suture (geology), sutured onto the ever-growing Laurentia, and together formed the stable Precambrian craton seen today. Etymology The craton is named after the Laurentian Shield, through the Laurentian Mountains, which received their name from the St. Lawrence River, named after Saint Lawrence of Rome. Interior platform In eastern and centra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
