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Azawagh Niger BMNG
The Azawagh (alias ''Azaouagh'' or ''Azawak'') is a dry basin covering what is today the northwestern Niger, as well as parts of northeastern Mali and southern Algeria. The Azawagh is mainly made up of Sahelian and Saharan flatlands and has a population that is predominantly Tuareg, with some Arabic-speaking, Bouzou and Wodaabe minorities and a recent influx of Hausa and Zarma. Name The Tuareg word ''azawaɣ'' means "savannah". Azawad, a term used for the portion of northern Mali claimed by the Tuareg rebel movement National Movement for the Liberation of Azawad, is believed to be an Arabic corruption of "Azawagh". Geography The Azawagh refers to the dry structural basin, which once carried a northern tributary of the Niger River, the Azawagh river, known as Dallol Bosso further south. The river, which ran some in prehistoric times, dried up after the Neolithic Subpluvial and created a basin of some . Its valley, which geologists call the Iullemmeden Basin, is bordere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azawad
Azawad, or Azawagh (Tuareg: Azawaɣ, or Azawad; ar, أزواد) was a short-lived unrecognised state from 2012 to 2013. Azawagh (''Azawaɣ'') is the generic Tuareg Berber name of all Tuareg Berber areas, especially the northern half of Mali and northern and western Niger. Its independence was declared unilaterally by the National Movement for the Liberation of Azawad (MNLA) in 2012, after a Tuareg rebellion drove the Malian Army from the region. Azawad, as claimed by the MNLA, comprises the Malian regions of Timbuktu, Kidal, Gao, as well as a part of Mopti region, encompassing about 60 percent of Mali's total land area. Azawad borders Burkina Faso to the south, Mauritania to the west and northwest, Algeria to the north and northeast, and Niger to the east and southeast, with undisputed Mali to its southwest. It straddles a portion of the Sahara and the Sahelian zone. Gao is its largest city and served as the temporary capital, while Timbuktu is the second-largest city, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Movement For The Liberation Of Azawad
The National Movement for the Liberation of Azawad or the Azawad National Liberation Movement (Tamasheq: '; ar, الحركة الوطنية لتحرير أزواد ''al-Ḥarakat al-Waṭaniyat Litaḥrīr ʾĀzawād''; french: Mouvement national de libération de l'Azawad, MNLA), formerly the National Movement of Azawad (french: Mouvement national de l'Azawad, MNA), is a political and military organisation based in Azawad in northern Mali. The movement is mostly made up of ethnic Tuareg, some of whom are believed to have fought in the Libyan army during the 2011 Libyan Civil War (though other Tuareg MNLA fighters were on the side of the National Transitional Council and returned to Mali after that war). The movement was founded in October 2011 and had stated that it includes other Saharan peoples. The Malian government has accused the movement of having links to Al-Qaeda in the Islamic Maghreb. The MNLA denies this claim. By 1 April 2012 the MNLA and Ansar Dine were in contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeolian Sand
Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth (or other planets). Winds may erode, transport, and deposit materials and are effective agents in regions with sparse vegetation, a lack of soil moisture and a large supply of unconsolidated sediments. Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts. The term is derived from the name of the Greek god Aeolus, the keeper of the winds. Definition and setting ''Aeolian processes'' are those processes of erosion, transport, and deposition of sediments that are caused by wind at or near the surface of the earth. Sediment deposits produced by the action of wind and the sedimentary structures characteristic of these deposits are also described as ''aeolian''. Aeolian processes are most important in areas where there is little o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clay is the oldest known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by Chicxulub impact, an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. In the Pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bedrock
In geology, bedrock is solid Rock (geology), rock that lies under loose material (regolith) within the crust (geology), crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedrock is often called an outcrop. The various kinds of broken and weathered rock material, such as soil and subsoil, that may overlie the bedrock are known as regolith. Engineering geology The surface of the bedrock beneath the soil cover (regolith) is also known as ''rockhead'' in engineering geology, and its identification by digging, drilling or geophysics, geophysical methods is an important task in most civil engineering projects. Superficial deposition (geology), deposits can be very thick, such that the bedrock lies hundreds of meters below the surface. Weathering of bedrock Exposed bedrock experiences weathering, which may be physical or chemical, and which alters the structure of the rock to leave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrar Des Ifoghas
The Adrar des Ifoghas (also Adrar des Iforas; Tamasheq: ⴰⴷⵔⴰⵔ ⵏ ⵉⴼⵓⵖⴰⵙ in Tifinagh; Adrar n Ifoghas; ar, أدرار إيفوغاس Ifoghas' Mountains) is a massif located in the Kidal Region of Mali, reaching into Algeria. It has an area of around 250,000 square kilometers (97,000 square miles). Geography The Adrar des Ifoghas area is characterized by wide, shallow valleys and is strewn with piles of eroded granite blocks. The massif's valleys open to the Tamesna plain on the east, to the Telemsi fosse on the west, to the western basin of the Azaouak valley on the south and to the Tanezrouft on the north. Settlements of the area include Kidal, Aguel'hoc, Boghassa, Essouk and Tessalit. The Adrar des Ifoghas is known locally as "Adagh". "Adrar" is the Berber word for mountain, while "Ifogha" is the name of an aristocratic Tuareg clan, "Kel Ifoghas", who have dominated the region for generations. Like most Tuareg, the Kel Ifoghas are nomadic, raising cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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-ton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoggar Mountains
The Hoggar Mountains ( ar, جبال هقار, Berber: ''idurar n Ahaggar'') are a highland region in the central Sahara in southern Algeria, along the Tropic of Cancer. The mountains cover an area of approximately 550,000 km. Geography This mountainous region is located about south of the capital, Algiers. The area is largely rocky desert with an average elevation of more than above sea level. The highest peak, Mount Tahat, is at . The mountains are primarily composed of metamorphic rock approximately 2 billion years old, although there are areas where more recent volcanic activity has laid down much newer rock. Several of the more dramatic peaks, such as Ilamen, are the result of erosion wearing away extinct volcano domes, leaving behind the more resistant material that plugged the volcanic cores. Assekrem is a famous and often visited point where Charles de Foucauld built a hermitage in 1911. The main city near the Hoggar Mountains is Tamanrasset, built in a desert val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iullemmeden Basin
The Iullemmeden Basin (Berber language: Iwellemmedden) is a major sub-Saharan inland basin in West Africa, extending about north to south and east to west. It covers western Niger and parts of Algeria, Mali and Nigeria. It is named after the Iullemmeden, a federation of Tuareg people who live in the central region of Niger. Its geographic range is largely coincident with the Azawagh region.Paris, 1995 Description The area of the Iullemmeden Basin seems to have started to subside in Permo-Triassic times, and to have experienced gradual downwarping during the Late Cretaceous to Paleogene times, while steadily filling with sediment. Two prominent fault trends run NNE-SSW through the center of the basin, while WSW-ENE faults trends are found in the northeast of the basin near the Aïr Mountains. Stratigraphy The sediments from Cambrian to Pleistocene times are thick, with alternating layers formed when the basin was undersea and above sea level. Potentially valuable minerals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
