{"title":"Geophysical investigations for groundwater in Precambrian terrains: a case history from Ikare, southwestern Nigeria","authors":"M.A. Olorunniwo, M.O. Olorunfemi","doi":"10.1016/0899-5362(87)90035-2","DOIUrl":null,"url":null,"abstract":"<div><p>Magnetic, very low frequency electromagnetic (VLF) and electrical resistivity methods have been applied in mapping buried bedrock relief for groundwater exploration in the Precambrian terrains of Ikare, southwestern Nigeria.</p><p>Quantitative interpretation of the magnetic data involved initial modelling and Euler deconvolution using elementary magnetic sources to identify applicable geological models in the spatial domain. A depth estimate of the top of the buried valley of 23 m was obtained. The application of power spectral deconvolution yielded an estimated depth of up to 67 m on the bedrock surface. The VLF data indicated the existence of subsurface lineament in the area while obtained resistivity of the sedimentary fill amounted to 260 ohm-m.</p><p>The results of the three techniques have successfully delineated a buried river channel for groundwater extraction in a crystalline basement terrain.</p></div>","PeriodicalId":100749,"journal":{"name":"Journal of African Earth Sciences (1983)","volume":"6 6","pages":"Pages 787-796"},"PeriodicalIF":0.0000,"publicationDate":"1987-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0899-5362(87)90035-2","citationCount":"40","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of African Earth Sciences (1983)","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0899536287900352","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 40
Abstract
Magnetic, very low frequency electromagnetic (VLF) and electrical resistivity methods have been applied in mapping buried bedrock relief for groundwater exploration in the Precambrian terrains of Ikare, southwestern Nigeria.
Quantitative interpretation of the magnetic data involved initial modelling and Euler deconvolution using elementary magnetic sources to identify applicable geological models in the spatial domain. A depth estimate of the top of the buried valley of 23 m was obtained. The application of power spectral deconvolution yielded an estimated depth of up to 67 m on the bedrock surface. The VLF data indicated the existence of subsurface lineament in the area while obtained resistivity of the sedimentary fill amounted to 260 ohm-m.
The results of the three techniques have successfully delineated a buried river channel for groundwater extraction in a crystalline basement terrain.