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Lake Nyos
Lake Nyos ( ) is a crater lake in the Northwest Region of Cameroon, located about northwest of Yaoundé, the capital. Nyos is a deep lake high on the flank of an inactive volcano in the Oku volcanic plain along the Cameroon line of volcanic activity. A volcanic dam impounds the lake waters. A pocket of magma lies beneath the lake and leaks carbon dioxide () into the water, changing it into carbonic acid. Nyos is one of only three lakes known to be saturated with carbon dioxide in this way, and therefore prone to limnic eruptions (the others being Lake Monoun, also in Cameroon, and Lake Kivu in the Democratic Republic of Congo and Rwanda). In 1986, possibly as the result of a landslide, Lake Nyos suddenly emitted a large cloud of , which suffocated 1,746 people and 3,500 livestock in nearby towns and villages, the most notable one being Chah, which was abandoned after the incident. The limnic eruption not only devastated human and livestock populations but also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Northwest Region (Cameroon)
The Northwest Region, or North-West Region () is a region with special status in Cameroon. Its capital is Bamenda. The Northwest Region was part of the Southern Cameroons, found in the western highlands of Cameroon. It is bordered to the southwest by the Southwest Region, to the south by the West Region, to the east by the Adamawa Region, and to the north by Nigeria. Various Ambazonian nationalist and separatist factions regard the region as being distinct as a polity from Cameroon. In 1919, the Northwest Region became solely administered by the United Kingdom. In 1961, the region joined the Cameroon.Emmanuel Mbah, ''Environment and Identity Politics in Colonial Africa: Fulani Migrations and Land Conflict'', Taylor & Francis, UK, 2016, p. 21 Ambazonian separatists regard both the North-West and South-West regions as being constituent components of their envisaged breakaway state. History The origins of the region are linked to the settlement of the Tikar people who jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lake Kivu
Lake Kivu is one of the African Great Lakes. It lies on the border between the Democratic Republic of the Congo and Rwanda, and is in the Albertine Rift, the western branch of the East African Rift. Lake Kivu empties into the Ruzizi River, which flows southwards into Lake Tanganyika. In 1894, German officer and colonial ruler Gustav Adolf von Götzen was the first recorded European to visit the lake. In the past, Lake Kivu drained toward the north, contributing to the White Nile. About 13,000 to 9,000 years ago, volcanism, volcanic activity blocked Lake Kivu's outlet to the watershed of the Nile. The volcanism produced mountains, including the Virunga Mountains, Virungas, which rose between Lake Kivu and Lake Edward, to the north. Water from Lake Kivu was then forced south down the Ruzizi. This, in turn, raised the level of Lake Tanganyika, which overflowed down the Lukuga River. Lake Kivu is one of three lakes in the world, along with Lake Nyos and Lake Monoun, that undergo lim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Maar
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow crater lake, which may also be called a maar.David S.G. Thomas and Andrew Goudie (eds.), ''The Dictionary of Physical Geography'' (Oxford: Blackwell, 2000), 301. . Maars range in size from across and from deep. Most maars fill with water to form natural lakes. Most maars have low rims composed of a mixture of loose fragments of volcanic rocks and rocks torn from the walls of the diatreme. Etymology The name ''maar'' comes from a Moselle Franconian dialect word used for the circular lakes of the Daun area of Germany. The word evolved from its first use in German in the modern geological sense in 1819 and is now used in English and in the geological sciences as the term for the explosion crater, even if water from rainfall might alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Stratovolcano
A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and explosive eruptions. Some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and solidifies before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high to intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less viscous mafic magma. Extensive felsic lava flows are uncommon, but can travel as far as 8 km (5 mi). The term ''composite volcano'' is used because strata are usually mixed and uneven instead of neat layers. They are among the most common types of volcanoes; more than 700 stratovolcanoes have erupted lava during the Holocene Epoch (the last 11,700 years), and many ol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Oku Volcanic Field
The Oku Volcanic Field or Oku Massif is a group of volcanoes based on a swell in the Cameroon Volcanic Line, located in the Oku region of the Western High Plateau of Cameroon. The Mount Oku stratovolcano rises to 3,011 m above sea level. The massif has a diameter of almost 100 km and contains four major stratovolcanoes: Mount Oku, Mount Babanki 15 km SW of Oku, Nyos and Nkambe. Rocks in the massif have ages from 24.9 to 22.1 million years ago, but more recent activity has occurred. The massif is composed of rhyolitic and trachytic rock, and contains many maars and basaltic cinder cones. The Oku Volcanic Field includes two crater lakes, Lake Nyos to the north and Lake Monoun to the south. On 15 August 1984, an earthquake and landslide triggered a major release of carbon dioxide from Lake Monoun, killing several people. Lake Nyos is inside a maar formed by an explosion about 400 years ago, and is about 1,800 m wide and 208 m deep. There is a low-temp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lake Nyos From Landsat, 2014
A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from the ocean, although they may be connected with the ocean by rivers. Lakes, as with other bodies of water, are part of the water cycle, the processes by which water moves around the Earth. Most lakes are fresh water and account for almost all the world's surface freshwater, but some are salt lakes with salinities even higher than that of seawater. Lakes vary significantly in surface area and volume of water. Lakes are typically larger and deeper than ponds, which are also water-filled basins on land, although there are no official definitions or scientific criteria distinguishing the two. Lakes are also distinct from lagoons, which are generally shallow tidal pools dammed by sandbars or other material at coastal regions of oceans or large la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Nigeria
Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, a population of more than 230 million, it is the List of African countries by population, most populous country in Africa, and the List of countries and dependencies by population, world's sixth-most populous country. Nigeria borders Niger in Niger–Nigeria border, the north, Chad in Chad–Nigeria border, the northeast, Cameroon in Cameroon–Nigeria border, the east, and Benin in Benin–Nigeria border, the west. Nigeria is a Federation, federal republic comprising 36 States of Nigeria, states and the Federal Capital Territory, Nigeria, Federal Capital Territory, where its capital, Abuja, is located. The List of Nigerian cities by population, largest city in Nigeria by population is Lagos, one of the largest List of largest cities, metr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Levee
A levee ( or ), dike (American English), dyke (British English; see American and British English spelling differences#Miscellaneous spelling differences, spelling differences), embankment, floodbank, or stop bank is an elevated ridge, natural or artificial, alongside the river banks, banks of a river, often intended to flood control, protect against flooding of the area adjoining the river. It is usually soil, earthen and often runs parallel (geometry), parallel to the course of a river in its floodplain or along low-lying coastlines. Naturally occurring levees form on river floodplains following flooding. Sediment and alluvium are deposition (geology), deposited on the banks and settle, forming a ridge that increases the river channel's capacity. Alternatively, levees can be artificially constructed from fill dirt, fill, designed to regulate water levels. In some circumstances, artificial levees can be environmental degradation, environmentally damaging. Ancient civilization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Smithsonian (magazine)
''Smithsonian'' is a magazine covering science, history, art, popular culture and innovation. The first issue was published in 1970. History The history of ''Smithsonian'' began when Edward K. Thompson, the retired editor of ''Life'' magazine, was asked by then-Secretary of the Smithsonian, S. Dillon Ripley, to produce a magazine "about things in which the Smithsonian nstitutionis interested, might be interested or ought to be interested." Thompson later recalled that his philosophy for the new magazine was that it "would stir curiosity in already receptive minds. It would deal with history as it is relevant to the present. It would present art, since true art is never dated, in the richest possible reproduction. It would peer into the future via coverage of social progress and of science and technology. Technical matters would be digested and made intelligible by skilled writers who would stimulate readers to reach upward while not turning them off with jargon. We would fin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chah (Cameroon)
Chah, or Cha, is a village in the Northwest Province of Cameroon that was largely abandoned after the Lake Nyos disaster of 1986, when an eruption of carbon dioxide from nearby Lake Nyos Lake Nyos ( ) is a crater lake in the Northwest Region of Cameroon, located about northwest of Yaoundé, the capital. Nyos is a deep lake high on the flank of an inactive volcano in the Oku volcanic plain along the Cameroon line of volcan ... killed many of its inhabitants. The village's population in 2005 was 593, 147 of which were men, and 446 were women. The village's infrastructure consists of at least seven kilometers of road, two bridges, and seven culverts. There are concerns about the stability of the natural rock wall that holds back the lake water. Regardless, the area was resettled after the disaster and reportedly has highly fertile soil. References Northwest Region (Cameroon) {{Cameroon-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
American Geophysical Union
The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, Atmospheric science, atmospheric, Oceanography, ocean, Hydrology, hydrologic, Astronomy, space, and Planetary science, planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international fields within the Earth and space sciences. The geophysical sciences involve four fundamental areas: atmospheric sciences, atmospheric and ocean sciences; solid-Earth sciences; hydrologic sciences; and space sciences. The organization's headquarters is located on Florida Avenue in Washington, D.C. History The AGU was established in December 1919 by the United States National Research Council, National Research Council (NRC) to represent the United States in the International Union of Geodesy and Geophysics (IUGG), and its first chairman w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Asphyxia
Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body which arises from abnormal breathing. Asphyxia causes generalized hypoxia, which affects all the tissues and organs, some more rapidly than others. There are many circumstances that can induce asphyxia, all of which are characterized by the inability of a person to acquire sufficient oxygen through breathing for an extended period of time. Asphyxia can cause coma or death. In 2015, about 9.8 million cases of unintentional suffocation occurred which resulted in 35,600 deaths. The word asphyxia is from Ancient Greek "without" and , "squeeze" (throb of heart). Causes Situations that can cause asphyxia include but are not limited to: airway obstruction (such as from asthma, laryngospasm, or simple blockage from the presence of foreign materials); from being in environments where oxygen is not readily accessible: such as underwater, in a low oxygen atmosphere, or in a vacuum; environments where s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
