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Aïr Mountains
The Aïr Mountains or Aïr Massif ( tmh, Ayăr; Hausa: Eastern ''Azbin'', Western ''Abzin'') is a triangular massif, located in northern Niger, within the Sahara. Part of the West Saharan montane xeric woodlands ecoregion, they rise to more than and extend over . Lying in the midst of desert north of the 17th parallel, the Aïr plateau, with an average altitude between , forms an island of Sahel climate which supports a wide variety of life, many pastoral and farming communities, and dramatic geological and archaeological sites. There are notable archaeological excavations in the region that illustrate the prehistoric past of this region. The endangered African wild dog (''Lycaon pictus'') once existed in this region, but may now be extirpated due to human population pressures in this region. Geology The Precambrian to Cenozoic Aïr Mountains consist of peralkaline granite intrusions which appear dark in colour (unusual since most granitic masses are light- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agadez Region
Agadez Region is one of the seven regions of Niger. At , it covers more than half of Niger's land area, and is the largest region in the country, as well as the largest African state subdivision. The capital of the department is Agadez. History The region is a centre for palaeontology, with numerous dinosaur skeletons being found here, including the '' Ouranosaurus nigeriensis''. Cave painting and the remains of ancient human settlements are also located here. Tuareg peoples began migrating to the region from the mid-8th century. From the mid-15th century to the early 20th, much of the region was under the control of the Sultanate of Agadez, except for a period when the area came under the rule of the Songhai Empire in the 1500s. The region suffered with the advent of French colonialism as power shifted away to the southwest; Tuareg disaffection with French rule resulted in the Kaocen revolt in 1916–17. This process continued following Niger's independence in 1960; local ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1997 278-13 Sahara Niger
File:1997 Events Collage.png, From left, clockwise: The movie set of ''Titanic'', the highest-grossing movie in history at the time; ''Harry Potter and the Philosopher's Stone'', is published; Comet Hale-Bopp passes by Earth and becomes one of the most observed comets of the 20th century; Golden Bauhinia Square, where sovereignty of Hong Kong is handed over from the United Kingdom to the People's Republic of China; the 1997 Central European flood kills 114 people in the Czech Republic, Poland, and Germany; Korean Air Flight 801 crashes during heavy rain on Guam, killing 229; Mars Pathfinder and Sojourner land on Mars; flowers left outside Kensington Palace following the death of Diana, Princess of Wales, in a car crash in Paris., 300x300px, thumb rect 0 0 200 200 Titanic (1997 film) rect 200 0 400 200 Harry Potter rect 400 0 600 200 Comet Hale-Bopp rect 0 200 300 400 Death of Diana, Princess of Wales rect 300 200 600 400 Handover of Hong Kong rect 0 400 200 600 Mars Pathfinde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrar Bous
Adrar Bous is a massif in the Aïr Mountains on the western edge of the Ténéré Desert, Niger. Archaeological research at Adrar Bous, conducted by J. Desmond Clark, has produced finds spanning the Late Acheulean (1.76 – 0.13 Ma) through the Neolithic (11,950 – 6,450 BP). The massif contains a number of sites where microlithic tools are present, along with faunal and human remains. Most notable are extensive remains of ritualized feasting by specialized Tenerian cattle pastoralists. Its name is written in the Tamasheq language. The massif itself has been dated to be about 487 million years old. Geology While the oldest formations in Adrar Bous date to the Precambrian period (~4600 – 541.0 ± 1.0 Ma), much of the ring-dike formation originated during the early Silurian period (443.8 ± 1.5 – 419.2 ± 3.2 Ma), likely due to the melting of the Saharan ice caps at that time. The massif is composed primarily of granite, and is host to a number of workable rocks: j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mont Greboun
Mont may refer to: Places * Mont., an abbreviation for Montana, a U.S. state * Mont, Belgium (other), several places in Belgium * Mont, Hautes-Pyrénées, a commune in France * Mont, Pyrénées-Atlantiques, a commune in France * Mont, Saône-et-Loire Mont () is a commune in the Saône-et-Loire department in the region of Bourgogne-Franche-Comté in eastern France. See also *Communes of the Saône-et-Loire department The following is a list of the 565 communes of the Saône-et-Loire depa ..., a commune in France Other uses * Mont (food), a category of Burmese snacks and desserts * Mont (surname) * Mont., botanical author abbreviation of Camille Montagne (1784-1866), French military physician and botanist * ''Seawise Giant'', the largest ship in the world, later renamed MV ''Mont'' for her final journey * Menthu or Mont, a deity in Egyptian mythology * M.O.N.T, South Korean boy group See also * Le Mont (other) * Monts (other) * Monte (disamb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion Surface
In geology and geomorphology, an erosion surface is a surface of rock or regolith that was formed by erosion and not by construction (e.g. lava flows, sediment deposition) nor fault displacement. Erosional surfaces within the stratigraphic record are known as unconformities, but not all unconformities are buried erosion surfaces. Erosion surfaces vary in scale and can be formed on a mountain range or a rock. Particularly large and flat erosion surfaces receive the names of peneplain, paleoplain, planation surface or pediplain. An example of erosion surface is road surface erosion which is caused by natural and anthropogenic factors. Erosion surface can be measured through direct, contact measurement methods and indirect, non-contact measurement methods. Road surface erosion Just like mountains and rocks, erosion can also occur on unsealed roads due to natural and anthropogenic factors. Road surface erosion could be caused by snowfall, rainfall and wind. The material an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Cambria ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plateau
In geology and physical geography, a plateau (; ; ), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. Often one or more sides have deep hills or escarpments. Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental. A few plateaus may have a small flat top while others have wide ones. Formation Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, Plate tectonics movements and erosion by water and glaciers. Volcanic Volcanic plateaus are produced by volcanic activity. The Columbia Plateau in the north-western United States is an example. They may be formed by upwelling of volcanic magma or extrus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G06 S65 63158
G, or g, is the seventh letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''gee'' (pronounced ), plural ''gees''. History The letter 'G' was introduced in the Old Latin period as a variant of ' C' to distinguish voiced from voiceless . The recorded originator of 'G' is freedman Spurius Carvilius Ruga, who added letter G to the teaching of the Roman alphabet during the 3rd century BC: he was the first Roman to open a fee-paying school, around 230 BCE. At this time, ' K' had fallen out of favor, and 'C', which had formerly represented both and before open vowels, had come to express in all environments. Ruga's positioning of 'G' shows that alphabetic order related to the letters' values as Greek numerals was a concern even in the 3rd century BC. According to some records, the original seventh letter, 'Z', had been purged from the Latin alphabet somewhat ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or '' granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
