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East Saharan Meta-craton
The Saharan Metacraton is a large area of continental crust in the north-central part of Africa. Whereas a craton is an old and stable part of the lithosphere, the term "metacraton" is used to describe a craton that has been remobilized during an orogenic event, but where the characteristics of the original craton are still identifiable. The geology of the continent has only been partially explored, and other names have been used to describe the general area that reflect different views of its nature and extent. These include "Nile Craton", "Sahara Congo Craton", "Eastern Saharan Craton" and "Central Saharan Ghost Craton". This last term is because the older rocks are almost completely covered by recent sediments and desert sands, making geological analysis difficult. Extent The "metacraton" covers an area of about . It lies between the Tuareg shield to the west, the Congo craton to the south, the Arabian-Nubian Shield to the east, and the northern African continental margin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pannotia
Pannotia (from Greek: ''wikt:pan-, pan-'', "all", ''wikt:νότος, -nótos'', "south"; meaning "all southern land"), also known as the Vendian supercontinent, Greater Gondwana, and the Pan-African supercontinent, was a relatively short-lived Neoproterozoic supercontinent that formed at the end of the Precambrian during the Pan-African orogeny (650–500 Megaannum, Ma), during the Cryogenian period and broke apart 560 Ma with the opening of the Iapetus Ocean, in the late Ediacaran and early Cambrian. Pannotia formed when Laurentia was located adjacent to the two major South American cratons, Amazonian craton, Amazonia and Río de la Plata craton, Río de la Plata. The opening of the Iapetus Ocean separated Laurentia from Baltica, Amazonia, and Río de la Plata. A 2022 paper argues that Pannotia never fully existed, reinterpreting the geochronology, geochronological evidence: "the supposed landmass had begun to break up well before it was fully assembled". However, the assembly of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central African Republic
The Central African Republic (CAR) is a landlocked country in Central Africa. It is bordered by Chad to Central African Republic–Chad border, the north, Sudan to Central African Republic–Sudan border, the northeast, South Sudan to Central African Republic–South Sudan border, the east, the Democratic Republic of the Congo to Central African Republic–Democratic Republic of the Congo border, the south, the Republic of the Congo to Central African Republic–Republic of the Congo border, the southwest, and Cameroon to Cameroon–Central African Republic border, the west. Bangui is the country's capital and largest city, bordering the Democratic Republic of the Congo. The Central African Republic covers a land area of about . As of 2024, it has a population of 5,357,744, consisting of about 80 ethnic groups, and is in the scene of a Central African Republic Civil War, civil war, which has been ongoing since 2012. Having been a Ubangi-Shari, French colony under the name Ubangi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of African Earth Sciences
The ''Journal of African Earth Sciences'' is a peer-reviewed scientific journal published by Elsevier established in 1983. It covers the earth sciences, primarily on issues that are relevant to Africa and the Middle East. Editorial board The editors-in-chief are Mohamed Abdelsalam (Oklahoma State University), Damien Delvaux (Royal Museum for Central Africa) et Read Mapeo ( University of Botswana). See also *'' GeoArabia'' *''South African Journal of Geology The ''South African Journal of Geology'' is a quarterly peer-reviewed scientific journal published by the Geological Society of South Africa that was established in March 1896 as the ''Transactions of the Geological Society of South Africa'', obt ...'' References External links * Geology journals Geology of Africa Elsevier academic journals English-language journals Academic journals established in 1983 {{geology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcontinent
Continental crustal fragments, partly synonymous with microcontinents, are pieces of continents that have broken off from main continental masses to form distinct islands that are often several hundred kilometers from their place of origin. Causes Continental fragments and microcontinent crustal compositions are very similar to those of regular continental crust. The rifting process that caused the continental fragments to form most likely impacts their layers and overall thickness along with the addition of mafic intrusions to the crust. Studies have determined that the average crustal thickness of continental fragments is approximately . The sedimentary layer of continental fragments can be up to thick and can overlay two to three crustal layers. Continental fragments have an average crustal density of which is very similar to that of typical continental crust. Strike-slip fault zones cause the fragmentation of microcontinents. The zones link the extensional zones where co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proterozoic
The Proterozoic ( ) is the third of the four geologic eons of Earth's history, spanning the time interval from 2500 to 538.8 Mya, and is the longest eon of Earth's geologic time scale. It is preceded by the Archean and followed by the Phanerozoic, and is the most recent part of the Precambrian "supereon". The Proterozoic is subdivided into three geologic eras (from oldest to youngest): the Paleoproterozoic, Mesoproterozoic and Neoproterozoic. It covers the time from the appearance of free oxygen in Earth's atmosphere to just before the proliferation of complex life on the Earth during the Cambrian Explosion. The name ''Proterozoic'' combines two words of Greek origin: meaning "former, earlier", and , meaning "of life". Well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the evolution of eukaryotes via symbiogenesis; several global glaciations, which produced the 300 million years-long Huronian glaciation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoggar Mountains
The Hoggar Mountains (; Berber: ''idurar n Ahaggar'') are a highland region in the central Sahara in southern Algeria, along the Tropic of Cancer. The mountains cover an area of approximately 550,000 km2. The Hoggar Mountains are home to the Ahaggar National Park. The tallest peak in the range and Algeria, Mount Tahat, is located in the park area, which covers approximately . Geography This mountainous region is located about south of the capital, Algiers. The area is largely rocky desert with an average elevation of more than above sea level. The highest peak, Mount Tahat, is at . The mountains are primarily composed of metamorphic rock approximately 2 billion years old, although there are areas where more recent volcanic activity has laid down much newer rock. Several of the more dramatic peaks, such as Ilamen, are the result of erosion wearing away extinct volcano domes, leaving behind the more resistant material that plugged the volcanic cones. Assekrem is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharusian Ocean
The Pharusian Ocean (; ) is an ancient ocean that existed on Earth from , between the break-up of the Rodinia supercontinent and the start of formation of the Pannotia 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 Ocean, lying to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zealandia, Arabian Peninsula, Arabia, and the Indian subcontinent. Gondwana was formed by the Accretion (geology), accretion of several cratons (large stable blocks of the Earth's crust), beginning with the East African Orogeny, the collision of India and Geography of Madagascar, Madagascar with East Africa, and culminating in with the overlapping Brasiliano orogeny, Brasiliano and Kuunga orogeny, Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of some , about one-fifth of the Earth's surface. It fused with Laurasia during the Carboniferous to form Pan ... [...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 (Ga) and broke up 750–633 million years ago (Ma). 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 plate 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 Ma. In contrast with Pannotia, little is known about Rodinia's configuration and geodynamic history. Paleomagnetic evidence provides some clues to the paleolatitude of individual pieces of the Earth's crus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pan-African Orogeny
The Pan-African orogeny was a series of major Neoproterozoic orogenic events which related to the formation of the supercontinents Gondwana and Pannotia about 600 million years ago. This orogeny is also known as the Pan-Gondwanan or Saldanian Orogeny. The Pan-African orogeny and the Grenville orogeny are the largest known systems of orogenies on Earth. The sum of the continental crust formed in the Pan-African orogeny and the Grenville orogeny makes the Neoproterozoic the period of Earth's history that has produced most continental crust. History and terminology The term ''Pan-African'' was coined by for a tectono-thermal event at about 500 Ma when a series of mobile belts in Africa formed between much older African cratons. At the time, other terms were used for similar orogenic events on other continents, i.e. '' Brasiliano'' in South America; ''Adelaidean'' in Australia; and ''Beardmore'' in Antarctica. Later, when plate tectonics became generally accepted, the term ''Pan-A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saharan Metacraton
The Saharan Metacraton is a large area of continental crust in the north-central part of Africa. Whereas a craton is an old and stable part of the lithosphere, the term "metacraton" is used to describe a craton that has been remobilized during an orogenic event, but where the characteristics of the original craton are still identifiable. The geology of the continent has only been partially explored, and other names have been used to describe the general area that reflect different views of its nature and extent. These include "Nile Craton", "Sahara Congo Craton", "Eastern Saharan Craton" and "Central Saharan Ghost Craton". This last term is because the older rocks are almost completely covered by recent sediments and desert sands, making geological analysis difficult. Extent The "metacraton" covers an area of about . It lies between the Tuareg shield to the west, the Congo craton to the south, the Arabian-Nubian Shield to the east, and the northern African continental margin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
