IJEP 41(10): 1160-1165 : Vol. 41 Issue. 10 (October 2021)
Jagadeshan*, B. Dessalegn, A. Abel B. Gosaye and J. Muralitharan
Arba Minch University, Department of Geology, College of Natural Science, Arba Minch, Ethiopia
Abstract
Electrical resistivity survey was carried out in Masgerdo river basin, Borena, southern Ethiopia, in order to assess the groundwater potential zones. Geologically, study area is underlain by volcanic basalt rocks, quaternary deposition and precambrian granitic basement rocks. 20 vertical electrical soundings were carried out with Schlumberger electrode configuration with current electrode spacing (AB/2) half ranging from 1-750 m. The measured apparent resistivity signals have been interpreted through curve matching technique using IX 1D software. The curves are prominently of QH, KH and HA type indicating the presence of 4 layers followed by a combination of curves QKA, KHK, KQH, QQH, QHK, QKK, HKH, QQQ and QHA indicating the presence of 5 sub-surface layers. Interpretations of resistivity data reveal the number of sub-surface layers, thickness and groundwater bearing capacity within the study area. The best layer which acts as the good groundwater aquifer of study area is the 3rd and 4th layer which consists of medium to highly weathered/fractured rock and unconsolidated sand formations at the depth between 4-20 m.
Keywords
Schlumberger electrode, Curve matching, Masgerdo river, Aquifer, Groundwater
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