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Mizane Birhan
Mizane Birhan is a ''tabia'' or municipality in the Dogu'a Tembien district of the Tigray Region of Ethiopia. The ''tabia'' centre is in Ma’idi village, located approximately 13 km to the southeast of the ''woreda'' town Hagere Selam (as the crow flies). Geography The ''tabia'' is astride the Imba Dogu’a ridge, between valleys of Rubaksa and Ruba Bich’i Rivers. The highest peak is Imba Dogu’a (2620 m a.s.l.) and the lowest place at east is along Ruba Bich’i (1960 m a.s.l.) and at west 2020 m, down from Addi Welo. Geology From the higher to the lower locations, the following geological formations are present: * Mekelle Dolerite, forming the large Imba Dogu’a batholite that dominates Mizane Birhan * Upper basalt * Interbedded lacustrine deposits * Lower basalt * Amba Aradam Formation * Agula Shale * Antalo Limestone: a large quarry south of Ma’idi * Quaternary alluvium and freshwater tufa Geomorphology and soils The main geomorphic u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopia
Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the north, Djibouti to the northeast, Somalia to the east and northeast, Kenya to the south, South Sudan to the west, and Sudan to the northwest. Ethiopia has a total area of . As of 2022, it is home to around 113.5 million inhabitants, making it the 13th-most populous country in the world and the 2nd-most populous in Africa after Nigeria. The national capital and largest city, Addis Ababa, lies several kilometres west of the East African Rift that splits the country into the African and Somali tectonic plates. Anatomically modern humans emerged from modern-day Ethiopia and set out to the Near East and elsewhere in the Middle Paleolithic period. Southwestern Ethiopia has been proposed as a possible homeland of the Afroasiatic langua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable beddin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Flood
A flash flood is a rapid flooding of low-lying areas: washes, rivers, dry lakes and depressions. It may be caused by heavy rain associated with a severe thunderstorm, hurricane, or tropical storm, or by meltwater from ice or snow flowing over ice sheets or snowfields. Flash floods may also occur after the collapse of a natural ice or debris dam, or a human structure such as a man-made dam, as occurred before the Johnstown Flood of 1889. Flash floods are distinguished from regular floods by having a timescale of fewer than six hours between rainfall and the onset of flooding. Flash floods are a significant hazard, causing more fatalities in the U.S. in an average year than lightning, tornadoes, or hurricanes. Flash floods can also deposit large quantities of sediments on floodplains and can be destructive of vegetation cover not adapted to frequent flood conditions. Causes Flash floods most often occur in dry areas that have recently received precipitation, but they may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mika'el Abiy
Mika’el Abiy is a ''tabia'' or municipality in the Dogu’a Tembien district of the Tigray Region of Ethiopia. The ''tabia'' centre is in Megesta village, located approximately 7 km to the southeast of the ''woreda'' town Hagere Selam. Geography The ''tabia'' stretches down south of the main road towards Rubaksa, which is a wider area with several springs and traditional irrigation. The highest peak is Gumawta (2815 m a.s.l.) on the Tsatsen plateau and the lowest place Rubaksa (1920 m a.s.l.). Geology and soils Geological formations From the higher to the lower locations, the following geological formations are present: * Upper basalt * Interbedded lacustrine deposits * Lower basalt * Amba Aradam Formation * Antalo Limestone * Quaternary alluvium and freshwater tufa Soilscape The main geomorphic units, with corresponding soil types are: * Hagere Selam Highlands, along the basalt and sandstone ridge ** Associated soil types *** shallow soils with high ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addi Azmera
Addi Azmera is a ''tabia'' or municipality in the Dogu'a Tembien district of the Tigray Region of Ethiopia. The name refers to good spring rains (“azmera”), in relation to the local microclimate. The ''tabia'' centre is in Tukhul town, located approximately half-way between the ''woreda'' town Hagere Selam and the regional capital Mekelle. Geography The ''tabia'' stretches on both sides of the main road that climbs towards Dogu’a Tembien after passing the bridge on Giba River. The highest location are the upper slopes of Imba Dogu’a (2590 m a.s.l.) and the lowest place along Giba River (1750 m a.s.l.). It comprises cultivated plains and steeper slopes, with often good vegetation (re)growth. Geology From the higher to the lower locations, the following geological formations are present: * Mekelle Dolerite * Amba Aradam Formation * Agula Shale - there are gypsum quarries in this formation, exploited by the cement factory of Mekelle * Antalo Limestone – many quarri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage System (geomorphology)
In geomorphology, drainage systems, also known as river systems, are the patterns formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and hydrologists often view streams as part of drainage basins (and sub-basins). This is the topographic region from which a stream receives runoff, throughflow, and its saturated equivalent, groundwater flow. The number, size, and shape of the drainage basins varies and the larger and more detailed the topographic map, the more information is available. Drainage patterns Per the lie of channels, drainage systems can fall into one of several categories, known as drainage patterns. These depend on the topography and geology of the land. All forms of transitions can occur between parallel, dendritic, and trellis patterns. Accordant versus discordant drainage patterns A drai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nile
The Nile, , Bohairic , lg, Kiira , Nobiin language, Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered the List of rivers by length, longest river in the world, though this has been contested by research suggesting that the Amazon River is slightly longer.Amazon Longer Than Nile River, Scientists Say Of the world's major rivers, the Nile is one of the smallest, as measured by annual flow in cubic metres of water. About long, its drainage basin covers eleven countries: the Democratic Republic of the Congo, Tanzania, Burundi, Rwanda, Uganda, Kenya, Ethiopia, Erit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tekezé River
The Tekezé or Täkkäze River ( amh, ተከዜ, ti, ተከዘ; originally meaning "river" in Ge’ez, ), also spelled Takkaze, is a major river of Ethiopia. For part of its course it forms a section of the westernmost border of Ethiopia and Eritrea. The river is also known as the Setit () in Eritrea, western Ethiopia, and eastern Sudan. According to materials published by the Ethiopian Central Statistical Agency, the Tekezé River is long. The canyon which it has created is the deepest in Africa and one of the deepest in the world, at some points having a depth of over 2000 meters (6,562 feet). Course The Tekezé River rises in the central Ethiopian Highlands near Mount Qachen within Lasta, from where it flows west, north, then west again, forming the westernmost border of Ethiopia and Eritrea from the confluence of the Tomsa with the Tekezé at to the tripoint between the two countries and Sudan at . After entering northeastern Sudan at the tripoint it joins the Atbarah ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertisol
A vertisol, or vertosol, is a soil type in which there is a high content of expansive clay minerals, many of them known as montmorillonite, that form deep cracks in drier seasons or years. In a phenomenon known as argillipedoturbation, alternate shrinking and swelling causes ''self-ploughing'', where the soil material consistently mixes itself, causing some vertisols to have an extremely deep A horizon and no B horizon. (A soil with no B horizon is called an ''A/C soil''). This heaving of the underlying material to the surface often creates a microrelief known as ''gilgai''. Vertisols typically form from highly basic rocks, such as basalt, in climates that are seasonally humid or subject to erratic droughts and floods, or that impeded drainage. Depending on the parent material and the climate, they can range from grey or red to the more familiar deep black (known as "black earths" in Australia, "black gumbo" in East Texas, "black cotton" soils in East Africa, and "vlei soils" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luvisol
Luvisols are a group of soils, comprising one of the 32 Reference Soil Groups in the international system of soil classification, the World Reference Base for Soil Resources The World Reference Base for Soil Resources (WRB) is an international soil classification system for naming soils and creating legends for soil maps. The currently valid version is the fourth edition 2022. It is edited by a working group of the Inte ... (WRB). They are widespread, especially in temperate climates, and are generally fertile. Luvisols are widely used for agriculture. Distribution Luvisols cover 500–600 million ha of land area, mainly in the temperate zones. They form on a wide variety of mineral parent materials. In Mediterranean regions, the formation of hematite can produce red-coloured Chromic Luvisols. Description and formation The main characteristic of Luvisols is an argic horizon, a subsurface zone with higher clay content than the material above it. This typically arises as clay is was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loam
Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–silt–clay, respectively. These proportions can vary to a degree, however, and result in different types of loam soils: sandy loam, silty loam, clay loam, sandy clay loam, silty clay loam, and loam. In the , textural classification triangle, the only soil that is not predominantly sand, silt, or clay is called "loam". Loam soils generally contain more nutrients, moisture, and |
Leptosol
A Leptosol in the World Reference Base for Soil Resources (WRB) is a very shallow soil over hard rock or a deeper soil that is extremely gravelly and/or stony. Leptosols cover approximately 1.7 billion hectares of the Earth's surface. They are found from the tropics to the cold polar regions and from sea level to the highest peaks. Leptosols are particularly widespread in mountain areas, notably in Asia, South America, northern Canada and Alaska; and in the Saharan and Arabian deserts. Elsewhere, Leptosols can be found on hard rocks or where erosion has kept pace with soil formation or removed the top of the soil. In the FAO soil classification for the UNESCO Soil Map of the World (1974) the Leptosols on calcareous rock were called Rendzinas, those on acid rock were Rankers. The very shallow, less than 10 cm deep, ''Lithic Leptosols'' in mountain regions are the most extensive Leptosols on Earth. Leptosols are unattractive soils for rainfed agriculture because of their inab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
