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Tanqua
Tanqwa is a river of northern Ethiopia. Rising in the mountains of Dogu’a Tembien (2510 metres above sea level), it flows westward to Giba River which empties finally in the Tekezé River. Hydrography It is a confined river, locally meandering in its narrow alluvial plain, with a slope gradient of 25 metres per kilometre. With its tributaries, the river has cut a deep gorge. Tributaries Tributaries, upstream from Abiy Addi, include * Tsech'i River * May Qoqah * Arwadito * Adawro River Hydrology Hydrological characteristics The runoff footprint or annual total runoff volume is 41 million m³ at the bridge in Abiy Addi and 79 million m³ at the confluence with Giba River at Barashuwa. Peak discharges up to 543 m³ per second occur in the second part of the rainy season (month of August) when there are strong rains and the soils are saturated with water in many places. The percentage of total rainfall that directly leaves the catchment as storm runoff (also called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abergele (woreda)
Tanqua Abergele ( ti, ጣንቋ ኣበáˆáŒˆáˆˆ, amh, አበáˆáŒˆáˆŒ) is one of the Districts of Ethiopia, or ''woredas'', in the Tigray Region of Ethiopia. Part of the Mehakelegnaw Zone, Abergele is bordered on the south by the Wag Hemra Zone of Amhara Region, then by the Tekezé River on the west which separates it from North Gondar Zone of Amhara Region, on the north by Kola Tembien, on the east by Degua Tembien and on the southeast by the Debub Misraqawi (South Eastern) Zone. The administrative center of this woreda is Yechila; other towns in Abergele include Sele and Jijike. Abergele is one of the low lying districts of central Tigray and the Tanqua River, which originates near Hagere Selam, flows through this woreda and joins the Geba just north of Jijike. It further feeds the Tekezé River. The Tekezé Dam is also located in this woreda. History It was a constituent of the old Tembien awrajja. Historically, Abergele seems to have formed a province since early tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abergele (woreda)
Tanqua Abergele ( ti, ጣንቋ ኣበáˆáŒˆáˆˆ, amh, አበáˆáŒˆáˆŒ) is one of the Districts of Ethiopia, or ''woredas'', in the Tigray Region of Ethiopia. Part of the Mehakelegnaw Zone, Abergele is bordered on the south by the Wag Hemra Zone of Amhara Region, then by the Tekezé River on the west which separates it from North Gondar Zone of Amhara Region, on the north by Kola Tembien, on the east by Degua Tembien and on the southeast by the Debub Misraqawi (South Eastern) Zone. The administrative center of this woreda is Yechila; other towns in Abergele include Sele and Jijike. Abergele is one of the low lying districts of central Tigray and the Tanqua River, which originates near Hagere Selam, flows through this woreda and joins the Geba just north of Jijike. It further feeds the Tekezé River. The Tekezé Dam is also located in this woreda. History It was a constituent of the old Tembien awrajja. Historically, Abergele seems to have formed a province since early times ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kola Tembien
Kola Tembien (, "Lower Tembien") is a woreda in Tigray Region, Ethiopia. It is named in part after the former province of Tembien. Part of the Mehakelegnaw Zone, Kola Tembien is bordered on the south by Abergele, on the west by the Tekezé River which separates it from the Semien Mi'irabawi (North Western) Zone, on the north by the Wari River which separates it from Naeder Adet and Werie Lehe, on the east by Misraqawi (Eastern) Zone, and on the southeast by Degua Tembien. Towns in Kola Tembien include Guya and Werkamba. The town of Abiy Addi is surrounded by Kola Tembien. Demographics Based on the 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), this woreda has a total population of 134,336, an increase of 28.13% over the 1994 census, of whom 66,925 are men and 67,411 women; 0 or 0.00% are urban inhabitants. With an area of 2,538.39 square kilometers, Kola Tembien has a population density of 52.92, which is 56.29 than the Zone average ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degua Tembien
Dogu'a Tembien (, "Upper Tembien", sometimes transliterated as Degua Tembien) is a woreda in Tigray Region, Ethiopia. It is named in part after the former province of Tembien. Nowadays, the mountainous district is part of the Southeastern Tigray Zone. The administrative centre of this woreda is Hagere Selam. History Dogu’a Tembien holds numerous prehistoric sites, which have been dated to the Middle Stone Age in Ayninbirkekin, or Pastoral Neolithic in Aregen and Menachek. Geography Topography and landscapes Major mountains :* Tsatsen, 2815 metres, a wide mesa between Hagere Selam and Inda Maryam Qorar () :* Ekli Imba, 2799 metres, summit of the Arebay massif in Arebay ''tabia'' or district () :* Imba Zuw’ala, 2710 metres, near Hagere Selam () :* Aregen, 2660 metres, in Aregen ''tabia'' () :* Dabba Selama, 2630 metres, in Haddinnet ''tabia'' () (not to be confused with the homonymous monastery) :* Imba Dogu’a, 2610 metres, in Mizane Birhan ''tabia'' () :* Imba Raâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degua Tembien
Dogu'a Tembien (, "Upper Tembien", sometimes transliterated as Degua Tembien) is a woreda in Tigray Region, Ethiopia. It is named in part after the former province of Tembien. Nowadays, the mountainous district is part of the Southeastern Tigray Zone. The administrative centre of this woreda is Hagere Selam. History Dogu’a Tembien holds numerous prehistoric sites, which have been dated to the Middle Stone Age in Ayninbirkekin, or Pastoral Neolithic in Aregen and Menachek. Geography Topography and landscapes Major mountains :* Tsatsen, 2815 metres, a wide mesa between Hagere Selam and Inda Maryam Qorar () :* Ekli Imba, 2799 metres, summit of the Arebay massif in Arebay ''tabia'' or district () :* Imba Zuw’ala, 2710 metres, near Hagere Selam () :* Aregen, 2660 metres, in Aregen ''tabia'' () :* Dabba Selama, 2630 metres, in Haddinnet ''tabia'' () (not to be confused with the homonymous monastery) :* Imba Dogu’a, 2610 metres, in Mizane Birhan ''tabia'' () :* Imb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ashangi Basalts
The Ashangi Basalts are the earliest Tertiary volcanic rocks in north Ethiopia, hence they are in the lowest position. These dark porphyritic basalts are separated from the Mesozoic formations below it by basal Conglomerate (geology), conglomerates. The basalts hold phenocrysts that developed before the magma reached the earth surface. These basalts are weathered, partially eroded and have a sub-horizontal stratification, particularly at the lower part. This series was created during the first period of the flood basalt eruptions in north Ethiopia, in the Oligocene. Name and definition The name was coined by geologist William Thomas Blanford, who accompanied the British Expedition to Abyssinia in 1868,{{cite book , last1=Blanford , first1=W.T. , title=Observations on the geology and zoology of Abyssinia, made during the progress of the British expedition to that country in 1867-68 , url=https://archive.org/details/cu31924024736666 , date=1870 , publisher=Macmillan and Co. , location ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Runoff Footprint
A runoff footprint is the total surface runoff that a site produces over the course of a year. According to the United States Environmental Protection Agency (EPA) stormwater is "rainwater and melted snow that runs off streets, lawns, and other sites". Urbanized areas with high concentrations of impervious surfaces like buildings, roads, and driveways produce large volumes of runoff which can lead to flooding, sewer overflows, and poor water quality. Since soil in urban areas can be compacted and have a low infiltration rate, the surface runoff estimated in a runoff footprint is not just from impervious surfaces, but also pervious areas including yards. The total runoff is a measure of the site’s contribution to stormwater issues in an area, especially in urban areas with sewer overflows. Completing a runoff footprint for a site allows a property owner to understand what areas on his or her site are producing the most runoff and what scenarios of stormwater green solutions like ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrograph
A hydrograph is a graph showing the rate of flow ( discharge) versus time past a specific point in a river, channel, or conduit carrying flow. The rate of flow is typically expressed in cubic meters or cubic feet per second (cms or cfs). It can also refer to a graph showing the volume of water reaching a particular outfall, or location in a sewerage network. Graphs are commonly used in the design of sewerage, more specifically, the design of surface water sewerage systems and combined sewers. Terminology ;Discharge: the rate of flow (volume per unit time) passing a specific location in a river, or other channel. The discharge is measured at a specific point in a river and is typically time variant. ;Approach Segment: the river flow before the storm (antecedent flow). ;Rising limb: The rising limb of the hydrograph, also known as concentration curve, reflects a prolonged increase in discharge from a catchment area, typically in response to a rainfall event. ;Peak discharge:'the hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Content
Water content or moisture content is the quantity of water contained in a material, such as soil (called soil moisture), rock, ceramics, crops, or wood. Water content is used in a wide range of scientific and technical areas, and is expressed as a ratio, which can range from 0 (completely dry) to the value of the materials' porosity at saturation. It can be given on a volumetric or mass (gravimetric) basis. Definitions Volumetric water content, θ, is defined mathematically as: :\theta = \frac where V_w is the volume of water and V_\text = V_s + V_w + V_a is equal to the total volume of the wet material, i.e. of the sum of the volume of solid host material (e.g., soil particles, vegetation tissue) V_s, of water V_w, and of air V_a. Gravimetric water content is expressed by mass (weight) as follows: :u = \frac where m_w is the mass of water and m_s is the mass of the solids. For materials that change in volume with water content, such as coal, the gravimetric water content, ''u' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stormwater
Stormwater, also spelled storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow. Stormwater can soak into the soil ( infiltrate) and become groundwater, be stored on depressed land surface in ponds and puddles, evaporate back into the atmosphere, or contribute to surface runoff. Most runoff is conveyed directly as surface water to nearby streams, rivers or other large water bodies (wetlands, lakes and oceans) without treatment. In natural landscapes, such as forests, soil absorbs much of the stormwater. Plants also reduce stormwater by improving infiltration, intercepting precipitation as it falls, and by taking up water through their roots. In developed environments, such as cities, unmanaged stormwater can create two major issues: one related to the volume and timing of runoff (flooding) and the other related to potential contaminants the water is carrying (water pollution). In addition to the pollutants carr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abiy Addi
Abiy Addi (also spelled Abi Addi; Tigrigna ዓብዪ ዓዲ "Big town") is a town in central Tigray Region, Tigray, Ethiopia. Abiy Addi is at the southeastern edge of the Kola Tembien woreda, of which it is the capital. Overview The town is divided into two parts by the Tanqwa, Tanqwa River, the lower part being the more respectable part while the upper part "is where you'll find the marketplace ... and the seedier bars in which you're most likely to see Awri dancing as the ''tej'' hits the mark." Briggs notes that Abiy Addi is known in Tigray for the frenetic style of dancing called "Awri", as well as the quality of its honey. Having visited Abiy Abbi in the mid-1940s, David Roden Buxton, David Buxton thought that "perhaps the best thing about Abbi Addi was the panorama of the Semien Mountains, Simien mountains standing to the west beyond the deep valley of the Tekezé." Buxton notes that the entire height of that mountain range was visible, from the southern foothills to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaji Basalts
The Alaji (upper) Basalts are the youngest series of the Ethiopian flood basalts. The most recent flows are only 15 million years old. Name and definition The name was coined by geologist William Thomas Blanford, who accompanied the British Expedition to Abyssinia in 1868, after the Imba Alaje mountain. So far the nomenclature has not been proposed for recognition to the International Commission on Stratigraphy. Stratigraphic context Uppermost Tertiary flood basalts in Ethiopia. Locally they are covered by Pliocene shield volcanoes, such as the Simien Mountains, or Mount Guna. These flows have been deposited on the lower Ashangi Basalts and locally on intra-volcanic sedimentary rock. Environment Like all volcanic rocks, the Alaji Basalts originate from initial melting of the Earth's mantle. After extrusion, the magmatic structures form at the surface. Common volcanic structures such as lava tubes or ropy lavas are absent in the Alaji Basalts, but (columnar joints) are omnipres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
