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Lengai And Lava, Ngorongoro District
Ol Doinyo Lengai is an active volcano in northern Tanzania. It consists of a volcanic cone with two craters, the northern of which has erupted during historical time. Uniquely for volcanoes on Earth, it has erupted natrocarbonatite, an unusually low temperature and highly fluid type of magma. Eruptions in 2007–2008 affected the surrounding region. Name The Maasai and Sonjo people refer to the volcano as "The Mountain of God", associated with a myth of the abode of the god Engai, who withdrew there after being hit by a hunter with an arrow. Other names are Basanjo, Donjo Ngai, Duenjo Ngai, Mongogogura, Mungogo wa Bogwe, and Oldonyo L'Engai. Geography and geomorphology Ol Doinyo Lengai lies in the Arusha region of Tanzania, south of Lake Natron and northwest of the city of Arusha. The summit was first explored between 1904 and 1915. , about 300,000 people live in the region, and livestock farming is the most important economic activity, although tourism is increasingly import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanzania
Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to the south; Zambia to the southwest; and Rwanda, Burundi, and the Democratic Republic of the Congo to the west. According to a 2024 estimate, Tanzania has a population of around 67.5 million, making it the most populous country located entirely south of the equator. Many important hominid fossils have been found in Tanzania. In the Stone and Bronze Age, prehistoric migrations into Tanzania included South Cushitic languages, Southern Cushitic speakers similar to modern day Iraqw people who moved south from present-day Ethiopia; Eastern Cushitic people who moved into Tanzania from north of Lake Turkana about 2,000 and 4,000 years ago; and the Southern Nilotic languages, Southern Nilotes, including the Datooga people, Datoog, who originated fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, 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 (geometry), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephelinite
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite). If olivine is present, the rock may be classified as an olivine nephelinite. Nephelinite is dark in color and may resemble basalt in hand specimen. However, basalt consists mostly of clinopyroxene (augite) and calcic plagioclase. Basalt, alkali basalt, basanite, tephritic nephelinite, and nephelinite differ partly in the relative proportions of plagioclase and nepheline. Alkali basalt may contain minor nepheline and does contain nepheline in its CIPW normative mineralogy. A critical ratio in the classification of these rocks is the ratio nepheline/(nepheline plus plagioclase). Basanite has a value of this ratio between 0.1 and 0.6 and also contains more than 10% olivine. Tephritic nephelinite has a value between 0.6 and 0.9. Nephelinite has a value greater than 0.9. Le Maitre (2002) defines and discusses these and other criteria in the classification of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melilite
Melilite refers to a mineral of the melilite group. Minerals of the group are solid solutions of several endmembers, the most important of which are gehlenite and åkermanite. A generalized formula for common melilite is ( Ca, Na)2( Al, Mg, Fe2+) Silicon">Si<_a>[.html" ;"title="Silicon.html" ;"title="Silicon">Si)Silicon">SiOxygen">O7 Discovered in 1793 near Rome, it has a yellowish, greenish-brown color. The name derives from the Greek words meli (μέλι) "honey" and lithos (λίθους) "stone".The name refers to a group of minerals (melilite group) with chemically similar composition, nearly always minerals in åkermanite-gehlenite series. Minerals of the melilite group are sorosilicates. They have the same basic structure, of general formula ''A''2''B(T''2O7). The melilite structure consist of pairs of fused ''T''O4, where ''T'' may be Si, Al, B, in bow-tie form. Sharing one corner, the formula of the pair is ''T''2O7. These bow-ties are linked togeth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilimanjaro
Mount Kilimanjaro () is a dormant volcano in Tanzania. It is the highest mountain in Africa and the highest free-standing mountain above sea level in the world, at above sea level and above its plateau base. It is also the highest volcano in the Eastern Hemisphere and the fourth most topographically prominent peak on Earth. Kilimanjaro's southern and eastern slopes served as the home of the Chagga Kingdoms until their abolition in 1963 by Julius Nyerere. The origin and meaning of the name Kilimanjaro is unknown, but may mean "mountain of greatness" or "unclimbable". Although described in classical sources, German missionary Johannes Rebmann is credited as the first European to report the mountain's existence, in 1848. After several European attempts, Hans Meyer reached Kilimanjaro's highest summit in 1889. The mountain was incorporated into Kilimanjaro National Park in 1973. As one of the Seven Summits, Kilimanjaro is a major hiking and climbing destination. There are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olduvai Gorge
The Olduvai Gorge or Oldupai Gorge in Tanzania is one of the most important paleoanthropology, paleoanthropological localities in the world; the many sites exposed by the gorge have proven invaluable in furthering understanding of early human evolution. A steep-sided ravine in the Great Rift Valley that stretches across East Africa, it is about 48 km long, and is located in the eastern Serengeti Plains within the Ngorongoro Conservation Area in the Olbalbal ward located in Ngorongoro District of Arusha Region, about from Laetoli, another important archaeological locality of early human occupation. The British/Kenyan paleoanthropologist-archeologist team of Mary Leakey, Mary and Louis Leakey established excavation and research programs at Olduvai Gorge that achieved great advances in human knowledge. The site is registered as one of the National Historic Sites of Tanzania. The gorge takes its name from the Maasai language, Maasai word ''oldupai'' which means "the place of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monogenetic Volcanic Field
A monogenetic volcanic field is a type of volcanic field consisting of a group of small monogenetic volcanoes, each of which erupts only once, as opposed to polygenetic volcanoes, which erupt repeatedly over a period of time. The small monogenetic volcanoes of these fields are the most common subaerial volcanic landform. Many monogenetic volcanoes are cinder cones, often with lava flows, such as Parícutin in the Michoacán-Guanajuato volcanic field, which erupted from 1943 to 1952. Some monogenetic volcanoes are small lava shields, such as Rangitoto Island in the Auckland volcanic field. Other monogenetic volcanoes are tuff rings or maars. A monogenetic field typically contains between ten and a hundred volcanoes. The Michoacán-Guanajuato field in Mexico contains more than a thousand volcanoes and is exceptionally large. Monogenetic fields occur only where the magma supply to the volcano is low or where vents are not close enough or large enough to develop plumbing syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelai
Gelai Volcano also known as Gelai (''Mlima Gelai'', in Swahili) stands at tall and is located in Longido District of Arusha Region in Tanzania. The volcano is located in the geographic area of the Crater Highlands and is a shield volcano that last erupted in the pleistocene. It is at the southeastern edge of Lake Natron in the East African Rift. Gelai is the third most prominent peak in Arusha Region and is the 13th highest peak in Arusha region. Volcanic activity on Gelai dates to less than one million years ago. A number of earthquakes occurred in the area in the summer of 2007. Associated with the largest earthquake on 17 July, a NNE-oriented fracture or narrow graben formed on the southern flank of Gelai. The fracture may be associated with the intrusion of a narrow dike at a depth of around . Forest Reserve Gelai Forest is a Local Government Reserve that was formed in 1955 and comprises around 2,341 acres of the isolated top of Gelai Hill, which has an elevation of 2,942 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed the Oligocene and preceded the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and Ape, hominoids into Eurasia. During the late Miocene, the conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crater Highlands
The Crater Highlands or Ngorongoro Volcanic Highlands (''Milima kasoko ya Ngorongoro '', in Swahili) are a geological region along the East African Rift in the Arusha Region and parts of northern Manyara Region in north Tanzania. The Crater Highlands are made up of several large volcanic complexes, including the 2.4-2.2 Ma Lemagarut and 2.25-2.0 Ma Ngorongoro basalt-trachybasalt- trachyandesite volcanoes (Ngorongoro also contains trachydacite) and the 1.6-1.5 Ma Oldeani basalt-trachyandesite volcano.Zaitsev, A., Marks, M., Wenzel, T., Spratt, J., Sharygin, V., Strekopytov, S., & Markl, G. (2012). Mineralogy, geochemistry and petrology of the phonolitic to nephelinitic Sadiman volcano, Crater Highlands, Tanzania. Lithos, 152, 66-83. https://doi.org/10.1016/j.lithos.2012.03.001 Geology The highlands are located in a spreading zone at the intersection of branches of two tectonic plates, the African Plate and Somali Plate, resulting in distinctive and prominent landforms. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
