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Pharusian Ocean
The Pharusian Ocean is an ancient ocean that existed from 800 to 635 million years ago, between the break-up of the Rodinia supercontinent and the start of formation of the Gondwana supercontinent. Opening and closure The Pharusian Ocean opened around 800 million years ago in the Neoproterozoic era after rifting along the eastern margin of the West African craton during the breakup of Rodinia. The ocean began to close around 730 million years ago with eastward subduction of the Tilemsi arc, which was accreted against the Hoggar region of the Saharan Metacraton. The western part of the Hoggar massif is made of material from the Pharusian Ocean including oceanic basalts, arc volcanic and sedimentary rocks and sediments that were shed into the Pharusian Ocean by the West African craton and the eastern Hoggar. Closure was completed when the West African and Saharan cratons collided around 635 million years ago at the start of the Pan-African orogeny. Southern extension The Goiás Oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodinia
Rodinia (from the Russian родина, ''rodina'', meaning "motherland, birthplace") was a Mesoproterozoic and Neoproterozoic supercontinent that assembled 1.26–0.90 billion years ago and broke up 750–633 million years ago. were probably the first to recognise a Precambrian supercontinent, which they named 'Pangaea I'. It was renamed 'Rodinia' by who also were the first to produce a reconstruction and propose a temporal framework for the supercontinent. Rodinia formed at c. 1.23 Ga by accretion and collision of fragments produced by breakup of an older supercontinent, Columbia, assembled by global-scale 2.0–1.8 Ga collisional events.; Rodinia broke up in the Neoproterozoic with its continental fragments reassembled to form Pannotia 633–573 million years ago. In contrast with Pannotia, little is known yet about the exact configuration and geodynamic history of Rodinia. Paleomagnetic evidence provides some clues to the paleolatitude of individual pieces of the ... [...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). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lineament
''See also Line (geometry)'' A lineament is a linear feature in a landscape which is an expression of an underlying geological structure such as a fault. Typically a lineament will appear as a fault-aligned valley, a series of fault or fold-aligned hills, a straight coastline or indeed a combination of these features. Fracture zones, shear zones and igneous intrusions such as dykes can also be expressed as geomorphic lineaments. Lineaments are often apparent in geological or topographic maps and can appear obvious on aerial or satellite photographs. There are for example, several instances within Great Britain. In Scotland the Great Glen Fault and Highland Boundary Fault give rise to lineaments as does the Malvern Line in western England and the Neath Disturbance in South Wales. The term 'megalineament' has been used to describe such features on a continental scale. The trace of the San Andreas Fault might be considered an example.Whitten & Brooks, The Penguin Dictionary of Geol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benin
Benin ( , ; french: Bénin , ff, Benen), officially the Republic of Benin (french: République du Bénin), and formerly Dahomey, is a country in West Africa. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the north-west, and Niger to the north-east. The majority of its population lives on the southern coastline of the Bight of Benin, part of the Gulf of Guinea in the northernmost tropical portion of the Atlantic Ocean. The capital is Porto-Novo, and the seat of government is in Cotonou, the most populous city and economic capital. Benin covers an area of and its population in was estimated to be approximately million. It is a tropical nation, dependent on agriculture, and is an exporter of palm oil and cotton. Some employment and income arise from subsistence farming. The official language of Benin is French, with indigenous languages such as Fon, Bariba, Yoruba and Dendi also spoken. The largest religious group in Benin is Sunni Isl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algeria
) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , religion = , official_languages = , languages_type = Other languages , languages = Algerian Arabic (Darja)French , ethnic_groups = , demonym = Algerian , government_type = Unitary semi-presidential republic , leader_title1 = President , leader_name1 = Abdelmadjid Tebboune , leader_title2 = Prime Minister , leader_name2 = Aymen Benabderrahmane , leader_title3 = Council President , leader_name3 = Salah Goudjil , leader_title4 = Assembly President , leader_name4 = Ibrahim Boughali , legislature = Parliament , upper_house = Council of the Nation , lowe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture Zone
In structural geology, a suture is a joining together along a major fault zone, of separate terranes, tectonic units that have different plate tectonic, metamorphic and paleogeographic histories. The suture is often represented on the surface by an orogen or mountain range. Overview In plate tectonics, sutures are the remains of subduction zones, and the terranes that are joined together are interpreted as fragments of different palaeocontinents or tectonic plates. Outcrops of sutures can vary in width from a few hundred meters to a couple of kilometers. They can be networks of mylonitic shear zones or brittle fault zones, but are usually both. Sutures are usually associated with igneous intrusions and tectonic lenses with varying kinds of lithologies from plutonic rocks to ophiolitic fragments. An example from Great Britain is the Iapetus Suture which, though now concealed beneath younger rocks, has been determined by geophysical means to run along a line roughly parallel w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trans Brazilian Lineament
The Trans Brazilian Lineament (TBL), or Transbrasiliano Lineament, is a major shear zone that developed in the Precambrian period, and that has been reactivated several times since then, mostly recently during the Mesozoic. Movement along the shear zone helps explain how the South American continent could have fitted tightly to the African continent before the breakup of Gondwana. Formation and location The TBL was formed when the Goiás Ocean, lying between the Amazonian craton and the Congo / Sao Francisco craton, was closed during the formation of West Gondwana around 600 million years ago. The lineament extends from the northeast coast of Brazil in a southwesterly direction through Paraguay and into Argentina, where it is dissipated in the Salado and Colorado extension basins. The Trans-Saharan Belt (TSB), running from Algeria to Benin, was created in the same period. It marks the line where the Pharusian Ocean, linked to the Goiás Ocean, was closed as the West African c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amazonian Craton
The Amazonian Craton is a geologic province located in South America. It occupies a large portion of the central, north and eastern part of the continent and represents one of Earth's largest cratonic regions. The Guiana Shield and Central Brazil Shield (Guaporé Shield) constitute respectively the northern and southern exhumed parts of the craton. Between the two shields lies the Amazon Rift, a zone of weakness within the craton. Smaller cratons of Precambrian rocks south of the Amazonian Shield are the Río de la Plata Craton and the São Francisco Craton, which lies to the east. The Río Apa Craton at the Paraguay-Brazil border is considered be likely just the southern part of the Amazonian Craton. The rocks of Río Apa were deformed during the Sunsás orogeny. It has been suggested that the Late Mesoproterozoic– Early Neoproterozoic aged Sveconorwegian Orogen in Fennoscandia could have been caused by a continent–continent collision between the Amazonia and Bal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercontinent
In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leaves room for interpretation and is easier to apply to Precambrian times. To separate supercontinents from other groupings, a limit has been proposed in which a continent must include at least about 75% of the continental crust then in existence in order to qualify as a supercontinent. Supercontinents have assembled and dispersed multiple times in the geologic past (see table). According to modern definitions, a supercontinent does not exist today; the closest in existence to a supercontinent is the current Afro-Eurasian landmass, which covers approx. 57% of Earth's total land area. The last time the continental landmasses were near to one another was 336 to 175 million years ago as the supercontinent, Pangaea. The positions of continent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goiás Ocean
Goiás () is a Brazilian state located in the Center-West region. Goiás borders the Federal District and the states of (from north clockwise) Tocantins, Bahia, Minas Gerais, Mato Grosso do Sul and Mato Grosso. The state capital is Goiânia. With 7.2 million inhabitants, Goiás is the most populous state in the Center-West and the 11th most populous in the country. It has the ninth largest economy among Brazilian federative units. In Brazil's geoeconomic division, Goiás belongs to the Centro-Sul (Center-South), being the northernmost state of the southern portion of Brazil. The state has 3.3% of the Brazilian population and is responsible for 2.7% of the Brazilian GDP. The history of Goiás dates back to the beginning of the 18th century, with the arrival of pioneers from São Paulo. The Rio Vermelho region was the first to be occupied, where Vila Boa (later renamed Goiás) was founded. The development and settlement of the state took place, in a more intensified way, start ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
