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Tadrart Rouge
The Tadrart Rouge (meaning "Red Mountain") or Southern Tadrart or Algerian Tadrart or Meridional Tadrart is a mountain range in southeastern Algeria, part of the Algerian Desert. The area has a rich array of rock art. Geography The ''Tadrart Rouge'' is a roughly 15–30 km large and 150 km long southern prolongation of the Libyan Tadrart Acacus into Algeria spanning to the frontier of Niger. Primarily composed of sandstone, it links the Tassili n’Ajjer in the north-west to the Djado in the southeast. The range is broken by a series of west-east oriented fossil drainage networks resulting in deep gorges. ''In Djaren'', discharging into the erg of ''Tin Merzuga'', is the most important one. The range reaches its maximum elevation of towards its southern end about 160 km southeast of Djanet. Erosion has formed a large number of natural arches. The area is well known for the spectacular red-orange sand dune fields contrasting with the jagged dark red rock formations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algeria
) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , religion = , official_languages = , languages_type = Other languages , languages = Algerian Arabic (Darja) French , ethnic_groups = , demonym = Algerian , government_type = Unitary semi-presidential republic , leader_title1 = President , leader_name1 = Abdelmadjid Tebboune , leader_title2 = Prime Minister , leader_name2 = Aymen Benabderrahmane , leader_title3 = Council President , leader_name3 = Salah Goudjil , leader_title4 = Assembly President , leader_name4 = Ibrahim Boughali , legislature = Parliament , upper_house = Council of the Nation , lower_house ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Djanet
Djanet ( ar, جانت) is an oasis city, and capital of Djanet District as well as of Djanet Province, southeast Algeria. It is located south of Illizi. According to the 2008 census it has a population of 14,655, up from 9,699 in 1998, and an annual population growth rate of 4.3%. It is inhabited by the Kel Ajjer Tuareg people. History The region of Djanet has been inhabited since Neolithic times. There were periods of ten thousand years at a time that the area was not desert. The flora and fauna were luxuriant as is seen in the numerous rock paintings of Tassili n'Ajjer around Djanet. Populations of hunter-gatherers lived there. Djanet was founded in the Middle Ages by the Tuareg. The Ottoman Empire, which had a nominal authority over the Fezzan region, reinforced their presence in the area at the beginning of the 20th century in reaction to the colonization of Africa by the Europeans. Geography Djanet, and the nearby towns of Azelouaz, El Mihan, Adjahil and Eferi, lie in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Africa
The history of Africa begins with the recent African origin of modern humans, emergence of hominids, archaic humans and — around 300–250,000 years ago—anatomically modern humans (''Homo sapiens''), in East Africa, and continues unbroken into the present as a patchwork of diverse and politically developing nation states. The earliest known recorded history Classical African civilization, arose in Ancient Egypt, and later in Nubia, the Sahel, the Maghreb, and the Horn of Africa. Following the desertification of the Sahara, North African history became entwined with the Middle East and Southern Europe while the Bantu expansion swept from modern day Cameroon (Central Africa) across much of the sub-Saharan continent in waves between around 1000 BC and 1 AD, creating a linguistic commonality across much of the central and Southern continent. During the Middle Ages, Islam spread west from Arabia to Egypt, crossing the Maghreb and the Sahel. Some notable pre-colonial states and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saharan Rock Art
Saharan rock art is a significant area of archaeological study focusing on artwork carved or painted on the natural rocks of the central Sahara desert. The rock art dates from numerous periods starting years ago, and is significant because it shows the culture of ancient African societies. The paintings and carvings of the Sahara are endangered, and vulnerable rock art on uncovered rock has already disappeared. Organizations, such as the Trust for African Rock Art, are researching and recording as much information about Saharan rock art as possible, while raising awareness of threats to the art itself. Archaeological sites Important regions and sites include: *Cave of Swimmers and Cave of Beasts caves area, Gilf Kebir area, Egypt *Tibesti, Chad: Also known as Tibesti Massif or Tibesti Mountains located in central Sahara, extending from Niger and Libya. The mountains are volcanic and are approximately long and wide. The rock art that exists in these mountains was created befor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Ranges Of Algeria
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable terrain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tifinagh
Tifinagh ( Tuareg Berber language: or , ) is a script used to write the Berber languages. Tifinagh is descended from the ancient Libyco-Berber alphabet. The traditional Tifinagh, sometimes called Tuareg Tifinagh, is still favored by the Tuareg Berbers of the Sahara desert in southern Algeria, northeastern Mali, northern Niger and northern Burkina Faso for use writing the Tuareg Berber language. Neo-Tifinagh () is an alphabet developed by Berber Academy to adopt Tuareg Tifinagh for use with Kabyle; it has been since modified for use across North Africa. Tifinagh is one of three major competing Berber orthographies alongside the Berber Latin alphabet and the Arabic script. Tifinagh is the official script for Tamazight, an official language of Morocco. However, outside of symbolic cultural uses, Latin remains the dominant script for writing Berber languages both in Morocco and throughout North Africa. The ancient Libyco-Berber script (or the Libyc script) was used by the an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stefan Kröpelin
Stefan Kröpelin is a geologist and climate researcher at the University of Cologne who specializes in studying the eastern Sahara desert and its climatic history. In 2017, he was awarded with thCommunicator Awardof the Deutsche Forschungsgemeinschaft for the excellent communication of his research both in Germany and international. Research The journal ''Nature'' described Kröpelin as "one of the most devoted Sahara explorers of our time." According to Siddiq Abd Algadir, president of the Sudanese Geologists' Union in Khartoum and a fellow student with Kröpelin in the 1980s, "Much of what we now know about the geology, the environments and even the people in some of the most remote parts of the Sahara, we really owe to tefan Kröpelinand the expeditions he has led." Contrary to other evidence that the Sahara suddenly changed from a wet to dry climate 5,000 years ago, Kröpelin's core samples at Lake Yoa suggests the transition took longer, some 3,000 years from 5,600 to 2,700 B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. According to '' Britannica'', there exists four savanna forms; ''savanna woodland'' where trees and shrubs form a light canopy, ''tree savanna'' with scattered trees and shrubs, ''shrub savanna'' with distributed shrubs, and ''grass savanna'' where trees and shrubs are mostly nonexistent.Smith, Jeremy M.B.. "savanna". Encyclopedia Britannica, 5 Sep. 2016, https://www.britannica.com/science/savanna/Environment. Accessed 17 September 2022. Savannas maintain an open canopy despite a high tree density. It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Humid Period
The African humid period (AHP) (also known by other names) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, trees and lakes was caused by changes in Earth's orbit around the Sun; changes in vegetation and dust in the Sahara which strengthened the African monsoon; and increased greenhouse gases. During the preceding Last Glacial Maximum, the Sahara contained extensive dune fields and was mostly uninhabited. It was much larger than today, but its lakes and rivers such as Lake Victoria and the White Nile were either dry or at low levels. The humid period began about 14,600–14,500 years ago at the end of Heinrich event 1, simultaneously to the Bølling–Allerød warming. Rivers and lakes such as Lake Chad formed or expanded, glaciers grew on Mount Kilimanjaro and the Sahara retreated. Two major dry fluctuations occurred; during the Youn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeoclimate
Paleoclimatology (British spelling, palaeoclimatology) is the study of climates for which direct measurements were not taken. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to understand natural variation and the evolution of the current climate. Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere. The scientific field of paleoclimatology came to maturity in the 20th century. Notable periods studied by paleoclimatologists are the frequent glaciations that Earth has undergone, rapid cooling events like the Younger Dryas, and the rapid warming during the Paleocene–Eocene Thermal Maximum. Studies of past changes in the environm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Arch
A natural arch, natural bridge, or (less commonly) rock arch is a natural landform where an arch has formed with an opening underneath. Natural arches commonly form where inland cliffs, coastal cliffs, fins or stacks are subject to erosion from the sea, rivers or weathering ( subaerial processes). Most natural arches are formed from narrow fins and sea stacks composed of sandstone or limestone with steep, often vertical, cliff faces. The formations become narrower due to erosion over geologic time scales. The softer rock stratum erodes away creating rock shelters, or alcoves, on opposite sides of the formation beneath the relatively harder stratum, or caprock, above it. The alcoves erode further into the formation eventually meeting underneath the harder caprock layer, thus creating an arch. The erosional processes exploit weaknesses in the softer rock layers making cracks larger and removing material more quickly than the caprock; however, the caprock itself continues to er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erg (landform)
An erg (also sand sea or dune sea, or sand sheet if it lacks dunes) is a broad, flat area of desert covered with wind-swept sand with little or no vegetative cover. The word is derived from the Arabic word ''ʿarq'' (), meaning "dune field". Strictly speaking, an erg is defined as a desert area that contains more than of aeolian or wind-blown sand and where sand covers more than 20% of the surface. Smaller areas are known as "dune fields". The largest hot desert in the world, the Sahara, covers and contains several ergs, such as the Chech Erg and the Issaouane Erg in Algeria. Approximately 85% of all the Earth's mobile sand is found in ergs that are greater than . Ergs are also found on other celestial bodies, such as Venus, Mars, and Saturn's moon Titan. Description Ergs are concentrated in two broad belts between 20° to 40°N and 20° to 40°S latitudes, which include regions crossed by the dry, subsiding air of the trade winds. Active ergs are limited to regions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
