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2005, Technical University of Denmark, Lund University.(На англ. / Грунтовые воды: оценка ресурсов с использованием традиционных методов, дистанционного зондирования и ГИС на примере южной периферийной части Эфиопии).
Abstract: Groundwater assessment is essential for drought prone areas such asNegelle Borena, southern peripheral part of Ethiopia, which suffers from,sever shortages of water. Major source of water for people in and aroundNegelle is the underexploited groundwater. This study has conductedhydrogeological investigation in a 250sqkm area of a drainage basin.Geological, hydrometeorological, hydrogeological, remote sensing andhydrochemical studies were implemented for studying the groundwaterresource in the area. The main objective of this study is to assessgroundwater resource using the results from multi-source data (satelliteimages, field measurements, hydrogeological and geochemical surveys).
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Groundwater resource assessment in hard rock terrain using conventional, remote sensing and GIS approach: a case study in southern peripheral part of Ethiopia EWRA2005 – Abstract – 022 Khalid Adem (1) Environment & Resources DTU, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark (2) Department of Water Resources Engineering, Lund University, SE-221 00 Lund, Sweden Abstract: Groundwater assessment is essential for drought prone areas such as Negelle Borena, southern peripheral part of Ethiopia, which suffers from, sever shortages of water. Major source of water for people in and around Negelle is the underexploited groundwater. This study has conducted hydrogeological investigation in a 250sqkm area of a drainage basin. Geological, hydrometeorological, hydrogeological, remote sensing and hydrochemical studies were implemented for studying the groundwater resource in the area. The main objective of this study is to assess groundwater resource using the results from multi-source data (satellite images, field measurements, hydrogeological and geochemical surveys). Geological studies have revealed that basement rocks consisting of gneissic and schist composition characterize half of the catchment. The basement is dissected by numerous fractures systems (NE-SW, NNE, SSW and E-W) and granite intrusive which facilitate movement of groundwater and contribute towards spring development. On the eastern portion of the study area, the Phanerozoic cover outcrops showing an increase in thickness up to 500m deep further towards the east. It consists of calcite rocks, clay, sand, and loam with intercalating shale units. The Phanerozoic unit constitutes aquifers, which facilitate deep groundwater systems Analysis of hydrometeorological components shows that mean precipitation for the catchment is about 647mm per annum. The area is characterized by bimodal type of rainfall, and the high proportion of the total amount of the annual rainfall comes from the first rainy season that lasts from March to May. Temperature in the study area varies from 13.9 o C low to 29.7 o C high. Actual evapotranspiration is evaluated using the simple “book keeping” Thornwait and Mather method and is found to be 1 2 Khalid Adem about 93.6% of the annual input from the precipitation. The mean annual recharge to the catchment is 31.4mm and about 9.2mm of water leaves the catchment as surface runoff Qualitative analysis has been conducted to characterize the different hydrolithologic units. From the analysis, five hydrostratigraphic units have been characterized based on porosity, permeability and storage capacity. Recharge area in the catchment is mainly confined to the Phanerozoic cover and the discharge areas are in the basement terrain. Application of the GIS and remote sensing shows that movement of groundwater in the study area is mainly c