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1983 Guinea Earthquake
On December 22, 1983 an earthquake with a magnitude of 6.3 struck northern Guinea, killing around 300 people, and injuring 1,500. Around 200 people went missing. An earthquake of this magnitude was unusual for this region of West Africa, which was previously believed by most seismologists to be Aseismic creep, aseismic. The earthquake destroyed 5,000 houses. It had an intensity of IX (Violent) on the Mercalli intensity scale, although United States Geological Survey, USGS reported it as VIII (Severe). The earthquake caused cracks in the ground, and an entire cavern to collapse. Geology The earthquake occurred on the edge of the Paleozoic Bové Basin, near the western margin of the Precambrian West African Craton and close to the southern end of the late Proterozoic to Variscan orogeny, Hercynian Mauritanide Belt. See also *List of earthquakes in 1983 *Geology of Guinea References Further reading

* {{Earthquakes in Africa Natural disasters in Guinea Earthquakes in Af ...
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Fault (geology)
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ...
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Proterozoic
The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided into three geologic eras (from oldest to youngest): the Paleoproterozoic, Mesoproterozoic, and Neoproterozoic. The Proterozoic covers the time from the appearance of oxygen in Earth's atmosphere to just before the proliferation of complex life (such as trilobites or corals) on the Earth. The name ''Proterozoic'' combines two forms of ultimately Greek origin: meaning 'former, earlier', and , 'of life'. The well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the evolution of eukaryotes; several glaciations, which produced the hypothesized Snowball Earth during the Cryogenian Period in the late Neoproterozoic Era; and the Ediacaran Period (635 to 538.8 Ma) which is characterize ...
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1983 In Guinea
The year 1983 saw both the official beginning of the Internet and the first mobile cellular telephone call. Events January * January 1 – The migration of the ARPANET to Internet protocol suite, TCP/IP is officially completed (this is considered to be the beginning of the true Internet). * January 24 – Twenty-five members of the Red Brigades are sentenced to life imprisonment for the 1978 murder of Italian politician Aldo Moro. * January 25 ** High-ranking Nazism, Nazi war crime, war criminal Klaus Barbie is arrested in Bolivia. ** IRAS is launched from Vandenberg AFB, to conduct the world's first all-sky infrared survey from space. February * February 2 – Giovanni Vigliotto goes on trial on charges of polygamy involving 105 women. * February 3 – Prime Minister of Australia Malcolm Fraser is granted a double dissolution of both houses of parliament, for 1983 Australian federal election, elections on March 5, 1983. As Fraser is being granted the dissolution, Bill Hayden ...
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December 1983 Events In Africa
December is the twelfth and final month of the year in the Julian and Gregorian calendars and is also the last of seven months to have a length of 31 days. December got its name from the Latin word ''decem'' (meaning ten) because it was originally the tenth month of the year in the calendar of Romulus which began in March. The winter days following December were not included as part of any month. Later, the months of January and February were created out of the monthless period and added to the beginning of the calendar, but December retained its name. Macrobius, '' Saturnalia'', tr. Percival Vaughan Davies (New York: Columbia University Press, 1969), book I, chapters 12–13, pp. 89–95. In Ancient Rome, as one of the four Agonalia, this day in honour of Sol Indiges was held on December 11, as was Septimontium. Dies natalis (birthday) was held at the temple of Tellus on December 13, Consualia was held on December 15, Saturnalia was held December 17–23, Opiconsivia ...
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Earthquakes In Africa
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from those that are so weak that they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time period. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume. The word ''tremor'' is also used for non-earthquake seismic rumbling. At the Earth's surface, earthquakes manifest themselves by shaking and displacing or disrupting the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes ca ...
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Natural Disasters In Guinea
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena. The word ''nature'' is borrowed from the Old French ''nature'' and is derived from the Latin word ''natura'', or "essential qualities, innate disposition", and in ancient times, literally meant "birth". In ancient philosophy, ''natura'' is mostly used as the Latin translation of the Greek word ''physis'' (φύσις), which originally related to the intrinsic characteristics of plants, animals, and other features of the world to develop of their own accord. The concept of nature as a whole, the physical universe, is one of several expansions of the original notion; it began with certain core applications of the word φύσις by pre-Socr ...
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Geology Of Guinea
Geologically, Guinea is covered by a crust of a very large Archean West African Craton with its northern and western regions having formations of younger Proterozoic rocks and its eastern region consists greenstone belts under the Birimian Supergroup which account for a major portion of West Africa's gold and iron ore reserves. Weathering of paleozoïcs schists has resulted in laterisiation leading to the formation of very large bauxite deposits. The geological formation of Guinean-Liberian belt is Precambrian and Paleozoic rocks. Large bauxite laterite deposits in Silurian shale and Ordovician sandstone have been sourced in the Tertiary by the dolerites; these are discovered in the Fouta Djalan mountain. In the northeastern part of the country, gold has been registered in Birimian. In the crystalline area of the north and south east of the country the prime mineral is iron ore which has itabirites. References Bibliography * External links
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List Of Earthquakes In 1983
This is a list of earthquakes in 1983. Only earthquakes of magnitude 6 or above are included, unless they result in damage and/or casualties, or are notable for some other reason. Events in remote areas will not be listed but included in statistics and maps. Countries are entered on the lists in order of their status in this particular year. All dates are listed according to UTC time. Maximum intensities are indicated on the Mercalli intensity scale and are sourced from United States Geological Survey (USGS) ShakeMap data. By death toll Listed are earthquakes with at least 10 dead. By magnitude Listed are earthquakes with at least 7.0 magnitude. By month January February March April May June July August September October References {{Earthquakes by year 1983 1983 earthquakes 1983 The year 1983 saw both the official beginning of the Internet and the first mobile cellular telephone call. Events January * January 1 – The ...
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Mauritanide Belt
The Mauritanide Belt is an ancient orogen running parallel to the west coast of Africa from Morocco to Guinea-Bissau. The orogeny that formed the Mauritanide Belt was active between 320 and 270 million years ago in the Carboniferous and Permian. During this time period the eastern nappes of the belt thrust over rocks of Devonian age in the Taoudeni Basin. During the Triassic the Mauritanide Belt was split from the Appalachian Mountains (with which it was previously a single orogen) as the Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ... opened. References Carboniferous orogenies Carboniferous Africa Orogenies of Africa Geology of Guinea-Bissau Geology of Mauritania Geology of Morocco Geology of Senegal Geology of the Gambia Permian orogenies Permian Afri ...
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Variscan Orogeny
The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea. Nomenclature The name ''Variscan'', comes from the Medieval Latin name for the district '' Variscia'', the home of a Germanic tribe, the Varisci; Eduard Suess, professor of geology at the University of Vienna, coined the term in 1880. (Variscite, a rare green mineral first discovered in the Vogtland district of Saxony in Germany, which is in the Variscan belt, has the same etymology.) ''Hercynian'', on the other hand, derives from the Hercynian Forest. Both words were descriptive terms of strike directions observed by geologists in the field, ''variscan'' for southwest to northeast, ''hercynian'' for northwest to southeast. The ''variscan'' direction reflected the direction of ancient fold belts cropping out throughout Germany and adjacent countries and the meaning shifted from d ...
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West African Craton
The West African Craton (WAC) is one of the five cratons of the Precambrian basement rock of Africa that make up the African Plate, the others being the Kalahari craton, Congo craton, Saharan Metacraton and Tanzania Craton.Jessell M.W., Liégeois J-P. (2015). "100 years of research on the West African Craton". ''Journal of African Earth Sciences''. 112(B): 377– 381. Cratons themselves are tectonically inactive, but can occur near active margins,Ennih N. & Liégeois J-P. (2008). ''The Boundaries of the West African Craton''. Geological Society, London, Special Publications. 297: 1–17. with the WAC extending across 14 countries in Western Africa, coming together in the late Precambrian and early Palaeozoic eras to form the African continent. It consists of two Archean centers juxtaposed against multiple Paleoproterozoic domains made of greenstone belts, sedimentary basins, regional granitoid-tonalite-trondhjemite-granodiorite, tonalite-trondhjemite-granodiorite (TTG) plutons, an ...
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Normal Fault
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ...
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