Investigating aquifer structure in a low-latitude crystalline basement complex of southwestern Nigeria using radial vertical electrical sounding

2021 ◽  
Vol 14 (4) ◽  
Author(s):  
Moruffdeen Adedapo Adabanija ◽  
Lanre Lateef Kolawole ◽  
Adegoke Olukayode Afolabi ◽  
Olawale Olakunle Osinowo
2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Akindeji O Fajana ◽  
Oluseun A Sanuade ◽  
Omolade T Olawunmi ◽  
Ajibola R Oyebamiji

This study compared the interpretation results of the Vertical Electrical Sounding (VES) data acquired using the conventional Schlumberger and modified Schlumberger arrays with a view to assessing the effectiveness of the modified Schlumberger arrays of VES as alternatives to the conventional Schlumberger array at sites with space constraint during geophysical exploration. A total of thirty (30) VES data for both conventional Schlumberger and modified Schlumberger arrays were collected across different rock units within Federal University Oye-Ekiti campus and Irare estate in Oye-Ekiti metropolis, south-western Nigeria, with electrode spacing (


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Ahmed Babeker Elhag

The geology and hydro-geophysical features can aid in identifying borehole location. The study aims to investigate groundwater aquifers and best location of boreholes in the crystalline basement area of Abu Zabad near El Obeid Southwest, Sudan. The study area is underlain by two aquifers formations from Precambrian age. The oldest units of basement complex of area under investigation consist of metamorphic rocks including gneiss, schist, and quartzite.The geophysical methods electromagnetic (EM) and vertical electrical sounding (VES) surveys showed that best aquifers yield for construction of boreholes are in weathering and fractures formation. The EM results revealed that structural features are significant for groundwater potential and interpretation of the VES data also revealed four geo-electric layers, but generally two distinct lithologic layers, which include Superficial deposit and bedrock-basement respectively. The curves generated from the data revealed H curve and HK curve, and thickness of these layers varies from 15 m to 50 m in the area. The aquifer thickness range from 20 m to 30 m. The study concludes that these techniques are suitable for identifying borehole location in the basement rock in Abu Zabad Area Sudan.


2018 ◽  
Vol 65 (1) ◽  
pp. 45-58
Author(s):  
A.A. Oyedele ◽  
G.M. Olayanju ◽  
A.O. Talabi ◽  
S.N. Ogunyebi ◽  
O.F. Ojo

AbstractVertical electrical sounding, well inventory and physicochemical analysis were conducted to evaluate soil corrosivity and aquifer protective capacity of overburden units in the basement complex terrain of Ado-Ekiti, southwestern Nigeria. The topsoil is composed of slightly corrosive materials at the eastern, southern and northeastern flanks and the central portion with resistivity values ranging from 60 to 180 Ωm. Moderately corrosive/slightly corrosive materials (with resistivity values of 10 < ρ < 60 Ωm) constitute the second layer around the eastern, southern and north-eastern flanks. Pockets of areas in the northwestern, southeastern, eastern and central parts of the metropolis are practically non-corrosive with resistivity values in excess of 200 Ωm. Zones of good, moderate, weak and poor overburden protective capacity were delineated, with longitudinal conductance (S) values of 0.7 < S < 4.9, 0.2 < S < 0.69, 0.1 < S < 0.19 and S < 0.1 mhos, respectively. On a regional consideration, 23.31%, 18.80% and 57.9% of the study area is characterised by overburden materials of poor, weak and moderate protective capacity, respectively. Only 6.02% of the area indicates good overburden protective capacity.


Author(s):  
Priscillia Egbelelulu ◽  
Taiwo Adewumi ◽  
Emmanuel Emeka Udensi ◽  
Naeem Abdulsalam ◽  
Oke Israel Okwokwo

This research work focused on the use of direct current resistivity method to analyse data collected from refuse dumpsite at eastern bye pass Minna. The study area lies approximately on longitude 60 36’19.84”E to 6036’23.15”E and latitude 90 38’04.97”N to 9038’08.25”N, with a dimension of 100m x 100m within the basement complex of north central Nigeria. Vertical Electrical Sounding was carried out on the dumpsite with the aim of delineating the leachate contaminant plumes using resistivity method. Nine electrical resistivity profiles were measured on the site. Six transverse profiles were conducted on the dumpsite with thirty-six vertical electrical sounding (VES) point, three transverse profiles was also conducted on the control site which is 100 meters away from the dumpsite having nine vertical electrical sounding (VES) point and a dimension of 40m x 40m. The resistivity data obtained was analyzed using winresist software. The data obtained from the study area revealed three underlain layer they are the topsoil, fractured basement and fresh basement. The dumpsite was typified by A-types and H-types of curve and the control site was typified by H-type of curves. Iso–resistivity maps at various depths were observed, at the surface, 3m, 5m,7m, and 10m for the dumpsite and the control site. It can therefore be inferred from this study that the depth of contamination is 7 meter and aquifer found within this depth are most likely to be contaminated by leachate and water bearing formation beyond the depth of 7m is safe from contamination. The rate of contamination of the study area is approximately 1.0 meter per year.


2021 ◽  
Author(s):  
'Muyiwa Adekunle Adeyanju ◽  
Oluwaseun Victoria Fatoye ◽  
O.E Oyanameh

Abstract The study aims to integrate magnetic and vertical electrical sounding (VES) resistivity methods to determine groundwater prospective in part of Aran-orin Sheet 224. A total of three traverses were established in the study area for the vertical electrical sounding using the Schlumberger electrode configuration. A total of 17 VES points was established using the ABEM Terrameter SAS 1000C model with maximum half-current electrode spacing (AB/2) of 120m. A total of eight traverses were established for the magnetics survey with station intervals of 10 m and inter-profile spacing of 100 m. The magnetic and VES data were qualitatively and quantitatively interpreted using IPI2WIN and OASIS MONTAJ package respectively. The geo-electric sections reveal a maximum of 3-4 layers beneath the sub-surface an overburden thickness ranges from 8.2 m to 64.9 m and the corresponding lithology inferred are topsoil, weathered Rock, fractured basement and fresh basement. The depth to basement using half-width method showed that the depth ranges from 8.4-56.04 m, which corresponds with the electrical survey.


Author(s):  
Cyril Chibueze Okpoli ◽  
Blessing omobolanle Akinbulejo

AbstractAeromagnetic and vertical electrical sounding around Ijano, southwestern Nigeria, was investigated for groundwater potential. Aeromagnetic dataset and vertical electrical sounding were acquired and used to investigate the study area. Oasis Montaj, Microsoft Excel and Arc GIS were used to present the results in maps, images and profiles. In order to map out the geological structures of the study area, magnetic image enhancing filters applied to the total magnetic intensity using Geosoft (Oasis Montaj) are reduction to equator, vertical derivative, total horizontal derivative and upward continuation. These filters helped define the lithological boundaries, geological structures, faults, folds and contacts. The lineament of aeromagnetic map was generated from derived field intensity gradients and solutions of Euler deconvolution carried out on the aeromagnetic data using structural index of 0.5 and 1. The processed image shows the lineaments trends majorly towards NE–SW directions. From these combined results of the study area, consistent aeromagnetic lineament map was generated showing the probable positions and trends of the suspected fractured/faulted zone as well as other basement structures. Hydro-lineament density maps based on lineament were produced from the generalized structure trends in the area. The result from the depth sounding data interpretation indicates three curve types which are H, HA and KH, where curve type H has the highest occurrence. The results from the vertical electrical sounding data revealed that the areas with the highest hydro-lineament density are good for groundwater prospect and development. The study has led to the delineation of areas where groundwater occurrences are most promising for sustainable supply, suggesting that an area with high concentrations of lineament density has a high tendency for groundwater prospecting. The results from the study show that the aeromagnetic technique is capable of extracting lineament trends in an inaccessible tropical forest.


Sign in / Sign up

Export Citation Format

Share Document