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Erta Ale
Erta Ale (or Ertale or Irta'ale; Amharic: ኤርታሌ) is a continuously active basaltic shield volcano in the Afar Region of northeastern Ethiopia, which is itself part of the wider Afar Triangle (a barren desert region straddling Djibouti, Ethiopia and Eritrea). The volcano is located in the Danakil Depression, an area on the border between Ethiopia and Eritrea that is below sea level. It is the most active of the volcanoes in Ethiopia. Geology Erta Ale is high, with one or sometimes two active lava lakes at the summit which occasionally overflow on the south side of the volcano. It is notable for holding the longest-existing lava lake, present since at least 1906.Barnie, T.D., Oppenheimer, C., and Pagli, C. (2016). Magmatic Rifting and Active Volcanism. Geological Society, London, Special Publications, 420, 181–208. https://doi.org/10.1144/SP420.15 Volcanoes with lava lakes are rare: there were only eight in the world reported in 2019. ''Erta Ale'' means "smoking mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afar Region
The Afar Region (; ; ), formerly known as Region 2, is a Regions of Ethiopia, regional state in northeastern Ethiopia and the homeland of the Afar people. Its capital is the planned city of Semera, which lies on the paved Awash, Ethiopia, Awash–Assab highway. It is bordered by Eritrea to the north and Djibouti to the northeast; it also shares regional borders with the Tigray Region, Tigray, Amhara Region, Amhara, Oromia, Oromo and Somali Region, Somali regions. The Afar Triangle, the northern part of which is the Danakil Depression, is part of the Great Rift Valley, Ethiopia, Great Rift Valley of Ethiopia, and is located in the north of the region. It has the lowest point in Ethiopia and one of the lowest in Africa. The southern part of the region consists of the valley of the Awash River, which empties into a string of lakes along the Djibouti–Ethiopia border. Other notable landmarks include the Awash National Park. Demographics Based on the 2017 projections by the Centra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Volcanoes In Ethiopia
This is a list of volcanoes in Ethiopia. It includes both active and extinct vents. See also * List of mountains in Ethiopia * Geography of Ethiopia * Lists of volcanoes References {{Global Volcanism Program Lists of landforms of Ethiopia, Volcanoes Lists of volcanoes, Ethiopia Volcanoes of Ethiopia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afar Language
Afar is an Afroasiatic language belonging to the Cushitic branch, primarily spoken by the Afar people, native to parts of Djibouti, Eritrea and Ethiopia. It is an official language in Ethiopia; and a national language in Djibouti and Eritrea. Afar is officially written in the Latin script and has over 2.6 million speakers. Classification Afar is classified within the Cushitic branch of the Afroasiatic family. It is further categorized in the Lowland East Cushitic sub-group, along with Saho and Somali. Its closest relative is the Saho language. Geographic distribution The Afar language is spoken as a mother tongue by the Afar people in Djibouti, Eritrea, and the Afar Region of Ethiopia. According to '' Ethnologue'', there are total Afar speakers. Of these, 1,280,000 were recorded in the 2007 Ethiopian census, with 906,000 monolinguals registered in the 1994 census. Official status In Djibouti, Afar is a recognized national language. It is also one of the broadcasti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopian News Agency
The Ethiopian News Agency ( ''Ye-Ityopya Zéna Agelgelot'' (IZA) or ENA) is the official news agency of the government of Ethiopia. It is the oldest news organisation in Ethiopia. History and Activities Established in 1942 as a national wire news center, the Ethiopian News Agency has been gathering, compiling and disseminating news stories to the public through the mass media, websites and various social media platforms. As the oldest and experienced newscaster in the country, ENA has been disseminating news and related stories, documentary and TV programs through its 38 branch offices across the country. Moreover, the Agency publishes a bi-monthly magazine called Negari which features topical local and international issues and agenda of paramount importance. The agency broadcasts its news and programs in six local and foreign languages: Amharic, Afan Oromo, Tigrigna, English, Arabic and French. ENA was restructured and made accountable to the House of Peoples’ Representativ ... [...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] |
Dike (geology)
In geology, a dike or dyke is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reaches the surface. They are studied by geologists for the clues they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mafic
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase feldspar. Mafic materials can also be described as ferromagnesian. History The term ''mafic'' is a portmanteau of "magnesium" and "ferric" and was coined by Charles Whitman Cross, Joseph P. Iddings, Louis V. Pirsson, and Henry Stephens Washington in 1912. Cross' group had previously divided the major rock-forming minerals found in igneous rocks into ''salic'' minerals, such as quartz, feldspars, or feldspathoids, and ''femic'' minerals, such as olivine and pyroxene. However, micas and aluminium-rich amphiboles were excluded, while some calcium minerals containing little iron or magnesium, such as wollastonite or apatite, were included in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Crust
Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. The crust lies above the rigid uppermost layer of the mantle. The crust and the rigid upper mantle layer together constitute oceanic lithosphere. Oceanic crust is primarily composed of mafic rocks, or sima, which is rich in iron and magnesium. It is thinner than continental crust, or sial, generally less than 10 kilometers thick; however, it is denser, having a mean density of about 3.0 grams per cubic centimeter as opposed to continental crust which has a density of about 2.7 grams per cubic centimeter. The crust uppermost is the result of the cooling of magma derived from mantle material below the plate. The magma is injected into the spreading center, which consists mainly of a partly solidified crystal mush derive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Intrusion
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained ( phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 geological 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Sea Rift
The Red Sea Rift is a mid-ocean ridge between two tectonic plates, the African plate and the Arabian plate. It extends from the Dead Sea Transform fault system, and ends at an intersection with the Aden Ridge and the East African Rift, forming the Afar triple junction in the Afar Depression of the Horn of Africa. The Red Sea Rift was formed by the divergence between the African and Arabian plates. The rift transitioned from a continental rift to an oceanic rift. Magnetic anomalies suggest that the spreading rate on either side of the Red Sea is about 1 cm/year. The African plate has a rotation rate of 0.9270 degrees/ Ma (million years), while the Arabian plate has a rotation rate of 1.1616 degrees/Ma. Spreading model A two-stage spreading model explains the tectonic evolution in this region. The first major rift motion was seen in the lower/middle Eocene, followed by major seafloor spreading in the late Eocene and early Oligocene. This was followed by a period of 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
