- Vertical electrical sounding (VES) was used to map the groundwater potential of an industrial estate in Ogbomoso, Nigeria using 10 soundings.
- The soundings revealed 3-4 layer earth models consisting of topsoil, weathered/clay layers, fractured basement, and fresh basement.
- Maps of overburden thickness, weathered layer properties, and bedrock relief identified the southern and eastern parts as most promising for groundwater development, with the northeastern part considered fair.
Application of Electrical Resistivity Tomography for Soil Competence Study in...IIJSRJournal
This study was carried out to determine soil competence around University of Benin Teaching Hospital and its environs using electrical resistivity tomography method. The Wenner Schlumberger Array Profiling method was used to give information of the subsurface resistivity. The result of the study showed that in ERT 1, highly competent soil were observed with resistivity values between 725Ωm and greater than 6546Ωm, which means that the area is underlain by clay sand at the top and sand/laterite/bedrock at the bottom. ERT 2 is characterized by highly competent soils with high resistivity values between 899Ωm to greater than 7851 Ωm, which indicates that the soil is underlain by sand/laterite/bedrocks. Furthermore, ERT 3 is group as highly competent soils, with resistivity values between762Ωm and greater than 6980 Ωm; this shows that the profile 3 is underlain by sand/laterite/bed rock. The study shows that though most part of the area contains soils that are competent, because of the presence of clay which on most occasion in the Niger Delta are expandable, detailed Geophysical and Civil engineering studies should be carried out before the erection of high rising engineering structures such as network masts, buildings and water tanks within the study area.
Twelve vertical electrical soundings, VES, were carried out in parts of Abua in northwestern part of Rivers State in the sedimentary basin of the Niger delta of Nigeria, to determine the overburden layering and infer the aquifer depth/thickness and probable safe structural foundation depths in the region. The Schlumberger array method was employed using an ABEM 300B Terrameter and maximum current electrode spread of 400 m. The computed apparent resistivity field log values were plotted against the current electrode spreads and interpreted with IPWIN 2 and Sulphure 8 software to obtain the overburden thickness/depth, resistivity and the isopach map and then infer the subsoil layering thickness including potential aquifer zones within the depths of investigation in the area. The curve types revealed that three and four geoelectric sections were penetrated by the survey array with overburden thickness ranging from 4.2 m in Elok community to 91.7 m in Ilghom community. Potential aquifers with variable thickness from 5 to 60 m at depths of from 4.5 m and below the earth surface were identified. The subsurface soils types can support structural foundations from depths of 1.0 m and below the earth surface based on the type of building/engineering structures.
Integrated Geophysical and Geotechnical Evaluation of Foundation Failure in P...inventionjournals
Geophysical and geotechnical methods have been integrated with the aim of assessing characteristics of sub-surface layers to identify why structures in some parts of Ikere-Ekiti Southwestern Nigeria are failing or sinking as a result of foundation failure. Eight (8) vertical electrical sounding (VES) were carried out using resistivity meter and six (6) pits were dug to a depth of 1.2m. Six disturbed soil samples were collected from the six dug pits for the study. These samples were subjected to geotechnical tests in the laboratory, which include moisture content, shear test, Atterberg limit and grain size analysis. The acquired VES data were processed and interpreted using partial curve matching technique. The results of the all the mall the eight VES produced H curves. This curve type manifested three layers which are composed of sandy-clay, clayeysand/weathered basement and weathered basement/rock head. The depth o rockhead ranges from 12.1 to 43.2m. VES stations four and five have deeper depth to rock head (i.e. 21.3 to 43.2m) while other locations have lesser depth to rockhead (i.e.1 12.1m to 17.5m). The second layer has the lowest resistivity values meaning that it is somewhat conductive owing to clayey sand deposition and weathered area. Geotechnical test shows that the soils in the study area generally has high moisture content, low plasticity, and from grain size distribution, high concentrations of silt and clay. From the result, it is established that the layer in which the foundations are built upon are rated as poor to fairly competent. This might be as a result of poor drainage system characterised the study area which brought about the local deposition of the supposed subsoil. Therefore, high moisture content made the subsoil to lose its competency thereby causing the structures in the study area to subside
Geo-electric Investigation of the Cause of Structural Failure Indices on a Se...iosrjce
Electrical resistivity imaging has been employed to investigate the causes of structural failure related
cracks on a set of administrative buildings in southwestern Nigeria. The goals were to determine the
distribution of subsurface geologic lithologies beneath the set of buildings and therefrom infer the relative
strengths of such lithologies. Data were collected along four geo-electric traverses using the ABEM1000
Terrameter unit. The dipole-dipole array was utilized with an electrode separation of 5 m. Observed field data
were processed and inverted using a 2.5D finite-element modeling inversion algorithm. Results indicate that the
northeastern half of the site is underlain by unweathered basement rocks overlain by thin (generally < 4 m) soil
cover, while the southwestern region is dominated at depths beyond 4 m by low-resistivity water-saturated clays
and some weathering tills. The clays apparently receive abundant supply of water from a seasonal stream
channel adjacent to the westerly administrative blocks. The block presenting with the most damage has been
built out over the edge of the shallow basement rocks onto these less competent water-saturated clays in the
southeastern region resulting in cantilever-style differential settling. A second damaged block is situated
entirely on low resistivity water-saturated clays. Differential settling on this block is likely related to the
difference in thicknesses of the clays between sites of the north and south facing walls of the structure. Beneath
the northern wall, the clays are thinner and could be expected to compress less than at the southern wall.
Though uncalibrated to core or log data, the results allowed a first insight into possible causes of structural
failure on the buildings and it is hoped that palliative measures will benefit from these results.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Application of Electrical Resistivity Tomography for Soil Competence Study in...IIJSRJournal
This study was carried out to determine soil competence around University of Benin Teaching Hospital and its environs using electrical resistivity tomography method. The Wenner Schlumberger Array Profiling method was used to give information of the subsurface resistivity. The result of the study showed that in ERT 1, highly competent soil were observed with resistivity values between 725Ωm and greater than 6546Ωm, which means that the area is underlain by clay sand at the top and sand/laterite/bedrock at the bottom. ERT 2 is characterized by highly competent soils with high resistivity values between 899Ωm to greater than 7851 Ωm, which indicates that the soil is underlain by sand/laterite/bedrocks. Furthermore, ERT 3 is group as highly competent soils, with resistivity values between762Ωm and greater than 6980 Ωm; this shows that the profile 3 is underlain by sand/laterite/bed rock. The study shows that though most part of the area contains soils that are competent, because of the presence of clay which on most occasion in the Niger Delta are expandable, detailed Geophysical and Civil engineering studies should be carried out before the erection of high rising engineering structures such as network masts, buildings and water tanks within the study area.
Twelve vertical electrical soundings, VES, were carried out in parts of Abua in northwestern part of Rivers State in the sedimentary basin of the Niger delta of Nigeria, to determine the overburden layering and infer the aquifer depth/thickness and probable safe structural foundation depths in the region. The Schlumberger array method was employed using an ABEM 300B Terrameter and maximum current electrode spread of 400 m. The computed apparent resistivity field log values were plotted against the current electrode spreads and interpreted with IPWIN 2 and Sulphure 8 software to obtain the overburden thickness/depth, resistivity and the isopach map and then infer the subsoil layering thickness including potential aquifer zones within the depths of investigation in the area. The curve types revealed that three and four geoelectric sections were penetrated by the survey array with overburden thickness ranging from 4.2 m in Elok community to 91.7 m in Ilghom community. Potential aquifers with variable thickness from 5 to 60 m at depths of from 4.5 m and below the earth surface were identified. The subsurface soils types can support structural foundations from depths of 1.0 m and below the earth surface based on the type of building/engineering structures.
Integrated Geophysical and Geotechnical Evaluation of Foundation Failure in P...inventionjournals
Geophysical and geotechnical methods have been integrated with the aim of assessing characteristics of sub-surface layers to identify why structures in some parts of Ikere-Ekiti Southwestern Nigeria are failing or sinking as a result of foundation failure. Eight (8) vertical electrical sounding (VES) were carried out using resistivity meter and six (6) pits were dug to a depth of 1.2m. Six disturbed soil samples were collected from the six dug pits for the study. These samples were subjected to geotechnical tests in the laboratory, which include moisture content, shear test, Atterberg limit and grain size analysis. The acquired VES data were processed and interpreted using partial curve matching technique. The results of the all the mall the eight VES produced H curves. This curve type manifested three layers which are composed of sandy-clay, clayeysand/weathered basement and weathered basement/rock head. The depth o rockhead ranges from 12.1 to 43.2m. VES stations four and five have deeper depth to rock head (i.e. 21.3 to 43.2m) while other locations have lesser depth to rockhead (i.e.1 12.1m to 17.5m). The second layer has the lowest resistivity values meaning that it is somewhat conductive owing to clayey sand deposition and weathered area. Geotechnical test shows that the soils in the study area generally has high moisture content, low plasticity, and from grain size distribution, high concentrations of silt and clay. From the result, it is established that the layer in which the foundations are built upon are rated as poor to fairly competent. This might be as a result of poor drainage system characterised the study area which brought about the local deposition of the supposed subsoil. Therefore, high moisture content made the subsoil to lose its competency thereby causing the structures in the study area to subside
Geo-electric Investigation of the Cause of Structural Failure Indices on a Se...iosrjce
Electrical resistivity imaging has been employed to investigate the causes of structural failure related
cracks on a set of administrative buildings in southwestern Nigeria. The goals were to determine the
distribution of subsurface geologic lithologies beneath the set of buildings and therefrom infer the relative
strengths of such lithologies. Data were collected along four geo-electric traverses using the ABEM1000
Terrameter unit. The dipole-dipole array was utilized with an electrode separation of 5 m. Observed field data
were processed and inverted using a 2.5D finite-element modeling inversion algorithm. Results indicate that the
northeastern half of the site is underlain by unweathered basement rocks overlain by thin (generally < 4 m) soil
cover, while the southwestern region is dominated at depths beyond 4 m by low-resistivity water-saturated clays
and some weathering tills. The clays apparently receive abundant supply of water from a seasonal stream
channel adjacent to the westerly administrative blocks. The block presenting with the most damage has been
built out over the edge of the shallow basement rocks onto these less competent water-saturated clays in the
southeastern region resulting in cantilever-style differential settling. A second damaged block is situated
entirely on low resistivity water-saturated clays. Differential settling on this block is likely related to the
difference in thicknesses of the clays between sites of the north and south facing walls of the structure. Beneath
the northern wall, the clays are thinner and could be expected to compress less than at the southern wall.
Though uncalibrated to core or log data, the results allowed a first insight into possible causes of structural
failure on the buildings and it is hoped that palliative measures will benefit from these results.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Geophysical Investigation for Groundwater Potential in Rufus Giwa Polytechnic...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Geophysical Investigations of a Pavement Failure Along Akure-Ijare Road, Sout...iosrjce
Geophysical investigations were carried out along two failed segments of Akure-Ijare road, named
locality 1 and locality 2, with the aim of establishing the cause(s) of the incessant pavement failure along the
road. The geophysical investigations involved the Very Low Frequency Electromagnetic (VLF-EM) and
Electrical Resistivity Methods. The VLF-EM measurements were taken at intervals of 10 m along traverses
parallel to road pavements. Two techniques were adopted for the electrical resistivity method namely: the
vertical electrical sounding (VES) and a combination of horizontal profiling and sounding using dipole-dipole
configuration with inter stations separation (a) of 5 m and an expansion factor (n) that varies from 1 to 5. The
Schlumberger configuration was used for the VES with AB/2 varying from 1 to 65 m. Nine (9) and twelve (12)
VES were carried out at localities 1 and 2 respectively. The VLF-EM method revealed that the road pavement is
founded on a weakly conductive material devoid of major geological structure. The Vertical electrical sounding
curves range from A, H to KH. The geoelectric sections generally identified three to four geologic sequences
that comprise topsoil, weathered layer, partly weathered/fracture basement and fresh basement. At locality 1,
the topsoil/subsoil on which the road is founded are of low resistivity generally less than 100 Ω-m composed of
clayey materials, while the road pavement along locality 2 is within the resistive topsoil or directly on bedrock.
The bedrock along this locality is generally shallow (< 2 m) with an uneven interface. Therefore, from the
results of the investigation the causes of road failure in the studied roadway are heterogeneity and clayey nature
of the topsoil/sub-grade material, lack of proper drainage at the road embankment and poor construction
material.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Interpretation of Structural Terrace of Sheets: 303, 304 and 305 using Geophy...IIJSRJournal
The study on interpretation of aeromagnetic data of parts of Bamenda Massif (sheet 303, 304, and 305) South-eastern Nigeria has been evaluated. The data sets used are digitized maps of aeromagnetic data. The study area was characterized into four distinct zones such as A, B, C and D. Zone A occur in the northern portion and it is characterized by linear anomaly of amplitude 66.2 - 98.5nT. Zone B and C primarily share the same structural grain connecting the southwest and southern portions of the study area where they are characterised with large ''bull eye'' and narrow shaped anomalies. Zone D occupies the western and central portions of the study area showing features of magnetic highs and lows due to sporadic intrusions. The analysis review lineament structures aligned in a NE-SW and NW-SE trends which is in similar pattern to the initial rifting of the southern Nigerian margin system. Zone A, B and C are bound by intrusives of igneous origin. However, the interconnectivity of the structural lineaments makes them stand out as pathways for mineralization. Thus, most of the lineaments are believed to be located at a depth range of <246.5m to 258.2m, 258.2m to 437m, 212.9m to >626.1m and 769.2m to 1039.7m within the subsurface rocks.
This study was carried out to determine the subsurface lithology and possible depths for structural foundations in Ignatius Ajuru University of Education, Port Harcourt in southern Nigeria using electrical resistivity techniques of VES and borehole logging. Model ABEM SAS 300B Terrameter aided by SAS 200 log meter were used for the data collection while version IPWIN2 software was used for the processing of the VES data. Six profiles of different locations, using maximum current electrode spread of 200 m and maximum potential electrode spread of 30 m, were used to obtain resistivity range of 1.2 to 4335 Ωm for three to four geoelectric sections covering depth interval of 19.8 m in the area. The borehole data covered a depth range of 0 to 20 m. The results show lithostratigraphy sequence of silty sands, laterite, grain and coarse sands with resistivity values of 721 to 4000 Ωm. These soils can support structures with foundations as close as 0.5 m to 3 m or more below the earth surface because laterite and sandy soils have the ability of a firm grasp of structural foundations as they do not retain moisture that will cause foundational deformation and shifting that may eventually lead to collapse of the structures.
Subsurface Sedimentary Thickness and Structural types of Formations in Imo St...IIJSRJournal
Imo State is part of the Niger Delta of Nigeria that is blessed with a lot of natural resources. These have not been fully exploited and subsurface information of the region is needed to enhance the exploration of these resources. In this work airborne gravity data obtained from the Nigerian Geological Survey Agency has been interpreted to obtain information on the structural types, sedimentary thickness and hydrocarbon potentials of the state. These were archived by use of Oasis Montaj software. The residual gravity anomaly was first extracted from the field data with a polynomial operation and then enhanced by a high pass filter before gridding, modelling and depth estimation, using inverse and forward modelling and Euler deconvolution operation. The results reveal syncline and anticline structures with strike angles of varying degrees and strike-slip faults. The depth to evaluated anomalous bodies was between 4,001 m and 9,439 m, all located in the Ameki and Imo Formations which are composed of sandstones and shales. The structures and formations they occur are favorable environments for hydrocarbon habitation as is common in the Niger delta basin. The Euler depth estimates gave sedimentary thickness ranges of 113.5 m to 8,717 m and falls within basement depths in the Niger Delta
Investors have been avoiding the Okurike Barite due to paucity of
information on its economic worth in spite of the high demand for barites by the
local industries. This study was embarked upon to determine the spread and
industrial quality of the barite deposit in order to bridge the information gap. The
Okurike Barite mineralised site was investigated using geophysical Vertical
Electrical Sounding (VES) and Electrical Resistivity Tomography (ERT) and
geological techniques. The geophysical data were acquired along three profiles
while the barite samples were analysed using the laboratory techniques in order to
determine their elemental compositions and physical characteristics. Results show
that the barites occur with gravels, breccias and weathered basement materials
within a very limited region. The resistivity values of the barite mineralised region
were observed to vary between 731 and ~1500 Ωm. The barites are characterised by
specific gravity of 4.4, density of 3.64 g/cm3, porosity of 28%, uniaxial compressive
strength of 29.4 kN/mm2 and water absorption capacity of 1.5%. The elements Ba
and Fe dominate the elemental composition with 77.28 and 19.98% respectively.
BaO, Fe2O3 and MnO are preferentially enriched with abundance of 71.28, 21.40
and 6.10% respectively. These results show that the industrial quality of the
Okurike Barite is high although its spread is limited.
Geotechnical Investigation of Soil around Arawa-Kundulum Area of Gombe Town, ...iosrjce
This Project work involves the investigation of soil at Arawa- Kundulum area in Gombe town of
North Eastern Nigeria. The study area is a newly developing part of Gombe town but has been defaced by
cracks on buildings, and this calls for appropriate geotechnical investigation of soils of the area. Soil samples
were collected from eight (8) different locations within the study area. At each trial pit, four (4) samples were
collected at intervals of 0.5m, 1.0m, 1.5m and 2.0m depths below ground level and were investigated for their
Geotechnical properties with a view to classifying for their suitability or otherwise for infrastructural
development. The geotechnical tests carried out on these samples include: Natural moisture content, Specific
gravity, Physico-chemical tests, Particle size distribution (Sieve analysis), Atterberg limits and Compaction
tests. All these tests were carried out using the BS 1377, (1990) Parts 1 - 9 specification. Based on the test
results obtained from the study area, comparison were made with some standard specifications and it was
revealed that the soil samples are clayey soils which are unsuitable for most engineering construction because
they have poor bearing capacities. However from the investigation above, the main geotechnical problems that
affect design and engineering structures are found to be presence of expansive soil composed of silt and clay
with high plasticity index. This soil is therefore not recommended for Engineering purposes. In the event of
siting a building project, the soil should be stabilized before embarking on the project
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Geo Environmental Investigation of Abuad Dumpsite, Southwestern NigeriaIJERA Editor
Geoenvironmental study of ABUAD female dumpsite was conducted to investigate the suitability of its location
and potential impact on groundwater in the environment. Profiling and Vertical electrical sounding methods
were employed using Dipole - Dipole and Schlumberger configuration respectively. Five points were sounded
and one profile was occupied. Three heterogeneous subsurface lithologic units were established namely; lateritic
topsoil, clayey-sand, and, fresh basement. The curve types are simple H and HA. The topsoil and clayey-sand
materials are characterized with relatively low resistivity values while the fresh basement materials are
characterized with high resistivity values. The average resistivity and thickness values for the topsoil are
280.0Ωm and.2.3m respectively. Clayey-sand was encountered in all the locations with average resistivity and
thickness values of 32.0Ωm and 7.3m respectively. Basement is relatively shallow in the study area, it was
encountered in all the locations with an average resistivity and depth values to the top of basement of 674Ωm,
and 9.6m respectively. Overburden materials are relatively thin within the area with an average resistivity and
thickness values of 156Ωm, and 9.6m respectively. The overburden materials constituting the aquiferous units
within the study area are porous, vulnerable, and good paths for leachate migration. The relatively low
resistivity values within the clayey-sand layers (14 - 61Ωm) are suggestive of leachate intrusion, while relatively
high resistivity values of the impervious basement are due to their crystalline nature. The proximity of the
dumpsite to both the cafeteria and residential halls is a cause for concern.
Combined Geophysical And Geotechnical Techniques For Assessment Of Foundation...IRJESJOURNAL
Abstract: This study was carried out to assess the subsurface conditions around the school of technology complex in Lagos State Polytechnic, Ikorodu, using integrated geophysical and geotechnical techniques. The site lies within the Sedimentary terrain of southwestern Nigeria. Allied Ohmega Resistivity meter was used for data collection of 1-D and 2-D resistivitymeasurement while WinResist software and Dipro software were used for the processing respectively.The results of the vertical electrical sounding indicate that the depth to basement values ranges between 27.6 and 39.5m. The 2D resistivitysurvey has provided valuable information on the lateral and vertical variation of the layer competent for erecting foundation of engineering structures. The CPT probed an average depth of 4.8m and has identified material of very high shear strength associated with dense sand materials. The correlation of the three techniques used revealed similar soil layering consisting of topsoilsandy clay, coarse sand and sand.A mechanically stable coarse sand material was discovered as weathered layer which indicates high load bearing capacity suitable for foundation in the area and can support massive structures.
Subsurface 2D Image Analyses of the Uyangha Basement Area, South-Eastern NigeriaIOSR Journals
Geo-electric soundings were made in Stella Maris Secondary School, in Uyangha, Nigeria to image
the subsurface and obtain thicknesses and resistivities of different layers. A quantitative interpretation of the
data obtained clearly reveals the presence of four (4) geo-electric sections which are interpreted to be dry
laterite, moist laterite, weathered basement, and saturated basement. The depth probed is about 100m. The
saturated basement is the aquifer unit. Depth to aquifer unit in the area is at about 65m to 80m.The thickness of
the aquifer unit ranges from 20m to 35m. For ground water exploitation, boreholes in the area should therefore
be drilled to the depth of 91m, for reasonable groundwater yield. The lateritic layer makes the study area
suitable for building construction in the area.
Integrated Geophysical Studies Over Parts of Central Cross River State for th...iosrjce
A total of 71 Vertical Electrical Soundings were carried out using Schlumberger electrode
configuration for the evaluation of groundwater potential in parts of central Cross River State, Nigeria.
Interpretation of data showed three to six geoelectric layers. Productive shallow and deep aquifer zones were
identified at depths of 60 m and 150 m respectively, corresponding to a resistivity range of 100-500 Ωm for
shallow aquifers and 1000-2500 Ωm for deep aquifers respectively. The lithologic data of the aquifers revealed
sand/sandstone and very coarsed grained sand/fractured basement, respectively. Seismic refraction survey was
also carried out within the same study area for the foundation study of rocks. The studies revealed an average
thickness of 4.5 m (probably sand/clay) and 10.0 m (probably gravelly sand/shale) for the first and second
layers respectively. The range of velocities for the first three layers are 602 m/s to 960 m/s, 378 m/s to 2,424 m/s
and 1,587 m/s to 5,368 m/s, respectively, indicating that the soils in the area are not homogeneous. It is inferred
from the relative high values of calculated elastic constants in most of the locations, that the soils are well
consolidated and as such suitable for large engineering construction in such locations, while in the rest of the
locations the soils are considered unconsolidated and unsuitable for large construction work due to the relative
low values of the elastic constants.
Geophysical Investigation for Groundwater Potential in Rufus Giwa Polytechnic...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Geophysical Investigations of a Pavement Failure Along Akure-Ijare Road, Sout...iosrjce
Geophysical investigations were carried out along two failed segments of Akure-Ijare road, named
locality 1 and locality 2, with the aim of establishing the cause(s) of the incessant pavement failure along the
road. The geophysical investigations involved the Very Low Frequency Electromagnetic (VLF-EM) and
Electrical Resistivity Methods. The VLF-EM measurements were taken at intervals of 10 m along traverses
parallel to road pavements. Two techniques were adopted for the electrical resistivity method namely: the
vertical electrical sounding (VES) and a combination of horizontal profiling and sounding using dipole-dipole
configuration with inter stations separation (a) of 5 m and an expansion factor (n) that varies from 1 to 5. The
Schlumberger configuration was used for the VES with AB/2 varying from 1 to 65 m. Nine (9) and twelve (12)
VES were carried out at localities 1 and 2 respectively. The VLF-EM method revealed that the road pavement is
founded on a weakly conductive material devoid of major geological structure. The Vertical electrical sounding
curves range from A, H to KH. The geoelectric sections generally identified three to four geologic sequences
that comprise topsoil, weathered layer, partly weathered/fracture basement and fresh basement. At locality 1,
the topsoil/subsoil on which the road is founded are of low resistivity generally less than 100 Ω-m composed of
clayey materials, while the road pavement along locality 2 is within the resistive topsoil or directly on bedrock.
The bedrock along this locality is generally shallow (< 2 m) with an uneven interface. Therefore, from the
results of the investigation the causes of road failure in the studied roadway are heterogeneity and clayey nature
of the topsoil/sub-grade material, lack of proper drainage at the road embankment and poor construction
material.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Interpretation of Structural Terrace of Sheets: 303, 304 and 305 using Geophy...IIJSRJournal
The study on interpretation of aeromagnetic data of parts of Bamenda Massif (sheet 303, 304, and 305) South-eastern Nigeria has been evaluated. The data sets used are digitized maps of aeromagnetic data. The study area was characterized into four distinct zones such as A, B, C and D. Zone A occur in the northern portion and it is characterized by linear anomaly of amplitude 66.2 - 98.5nT. Zone B and C primarily share the same structural grain connecting the southwest and southern portions of the study area where they are characterised with large ''bull eye'' and narrow shaped anomalies. Zone D occupies the western and central portions of the study area showing features of magnetic highs and lows due to sporadic intrusions. The analysis review lineament structures aligned in a NE-SW and NW-SE trends which is in similar pattern to the initial rifting of the southern Nigerian margin system. Zone A, B and C are bound by intrusives of igneous origin. However, the interconnectivity of the structural lineaments makes them stand out as pathways for mineralization. Thus, most of the lineaments are believed to be located at a depth range of <246.5m to 258.2m, 258.2m to 437m, 212.9m to >626.1m and 769.2m to 1039.7m within the subsurface rocks.
This study was carried out to determine the subsurface lithology and possible depths for structural foundations in Ignatius Ajuru University of Education, Port Harcourt in southern Nigeria using electrical resistivity techniques of VES and borehole logging. Model ABEM SAS 300B Terrameter aided by SAS 200 log meter were used for the data collection while version IPWIN2 software was used for the processing of the VES data. Six profiles of different locations, using maximum current electrode spread of 200 m and maximum potential electrode spread of 30 m, were used to obtain resistivity range of 1.2 to 4335 Ωm for three to four geoelectric sections covering depth interval of 19.8 m in the area. The borehole data covered a depth range of 0 to 20 m. The results show lithostratigraphy sequence of silty sands, laterite, grain and coarse sands with resistivity values of 721 to 4000 Ωm. These soils can support structures with foundations as close as 0.5 m to 3 m or more below the earth surface because laterite and sandy soils have the ability of a firm grasp of structural foundations as they do not retain moisture that will cause foundational deformation and shifting that may eventually lead to collapse of the structures.
Subsurface Sedimentary Thickness and Structural types of Formations in Imo St...IIJSRJournal
Imo State is part of the Niger Delta of Nigeria that is blessed with a lot of natural resources. These have not been fully exploited and subsurface information of the region is needed to enhance the exploration of these resources. In this work airborne gravity data obtained from the Nigerian Geological Survey Agency has been interpreted to obtain information on the structural types, sedimentary thickness and hydrocarbon potentials of the state. These were archived by use of Oasis Montaj software. The residual gravity anomaly was first extracted from the field data with a polynomial operation and then enhanced by a high pass filter before gridding, modelling and depth estimation, using inverse and forward modelling and Euler deconvolution operation. The results reveal syncline and anticline structures with strike angles of varying degrees and strike-slip faults. The depth to evaluated anomalous bodies was between 4,001 m and 9,439 m, all located in the Ameki and Imo Formations which are composed of sandstones and shales. The structures and formations they occur are favorable environments for hydrocarbon habitation as is common in the Niger delta basin. The Euler depth estimates gave sedimentary thickness ranges of 113.5 m to 8,717 m and falls within basement depths in the Niger Delta
Investors have been avoiding the Okurike Barite due to paucity of
information on its economic worth in spite of the high demand for barites by the
local industries. This study was embarked upon to determine the spread and
industrial quality of the barite deposit in order to bridge the information gap. The
Okurike Barite mineralised site was investigated using geophysical Vertical
Electrical Sounding (VES) and Electrical Resistivity Tomography (ERT) and
geological techniques. The geophysical data were acquired along three profiles
while the barite samples were analysed using the laboratory techniques in order to
determine their elemental compositions and physical characteristics. Results show
that the barites occur with gravels, breccias and weathered basement materials
within a very limited region. The resistivity values of the barite mineralised region
were observed to vary between 731 and ~1500 Ωm. The barites are characterised by
specific gravity of 4.4, density of 3.64 g/cm3, porosity of 28%, uniaxial compressive
strength of 29.4 kN/mm2 and water absorption capacity of 1.5%. The elements Ba
and Fe dominate the elemental composition with 77.28 and 19.98% respectively.
BaO, Fe2O3 and MnO are preferentially enriched with abundance of 71.28, 21.40
and 6.10% respectively. These results show that the industrial quality of the
Okurike Barite is high although its spread is limited.
Geotechnical Investigation of Soil around Arawa-Kundulum Area of Gombe Town, ...iosrjce
This Project work involves the investigation of soil at Arawa- Kundulum area in Gombe town of
North Eastern Nigeria. The study area is a newly developing part of Gombe town but has been defaced by
cracks on buildings, and this calls for appropriate geotechnical investigation of soils of the area. Soil samples
were collected from eight (8) different locations within the study area. At each trial pit, four (4) samples were
collected at intervals of 0.5m, 1.0m, 1.5m and 2.0m depths below ground level and were investigated for their
Geotechnical properties with a view to classifying for their suitability or otherwise for infrastructural
development. The geotechnical tests carried out on these samples include: Natural moisture content, Specific
gravity, Physico-chemical tests, Particle size distribution (Sieve analysis), Atterberg limits and Compaction
tests. All these tests were carried out using the BS 1377, (1990) Parts 1 - 9 specification. Based on the test
results obtained from the study area, comparison were made with some standard specifications and it was
revealed that the soil samples are clayey soils which are unsuitable for most engineering construction because
they have poor bearing capacities. However from the investigation above, the main geotechnical problems that
affect design and engineering structures are found to be presence of expansive soil composed of silt and clay
with high plasticity index. This soil is therefore not recommended for Engineering purposes. In the event of
siting a building project, the soil should be stabilized before embarking on the project
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Geo Environmental Investigation of Abuad Dumpsite, Southwestern NigeriaIJERA Editor
Geoenvironmental study of ABUAD female dumpsite was conducted to investigate the suitability of its location
and potential impact on groundwater in the environment. Profiling and Vertical electrical sounding methods
were employed using Dipole - Dipole and Schlumberger configuration respectively. Five points were sounded
and one profile was occupied. Three heterogeneous subsurface lithologic units were established namely; lateritic
topsoil, clayey-sand, and, fresh basement. The curve types are simple H and HA. The topsoil and clayey-sand
materials are characterized with relatively low resistivity values while the fresh basement materials are
characterized with high resistivity values. The average resistivity and thickness values for the topsoil are
280.0Ωm and.2.3m respectively. Clayey-sand was encountered in all the locations with average resistivity and
thickness values of 32.0Ωm and 7.3m respectively. Basement is relatively shallow in the study area, it was
encountered in all the locations with an average resistivity and depth values to the top of basement of 674Ωm,
and 9.6m respectively. Overburden materials are relatively thin within the area with an average resistivity and
thickness values of 156Ωm, and 9.6m respectively. The overburden materials constituting the aquiferous units
within the study area are porous, vulnerable, and good paths for leachate migration. The relatively low
resistivity values within the clayey-sand layers (14 - 61Ωm) are suggestive of leachate intrusion, while relatively
high resistivity values of the impervious basement are due to their crystalline nature. The proximity of the
dumpsite to both the cafeteria and residential halls is a cause for concern.
Combined Geophysical And Geotechnical Techniques For Assessment Of Foundation...IRJESJOURNAL
Abstract: This study was carried out to assess the subsurface conditions around the school of technology complex in Lagos State Polytechnic, Ikorodu, using integrated geophysical and geotechnical techniques. The site lies within the Sedimentary terrain of southwestern Nigeria. Allied Ohmega Resistivity meter was used for data collection of 1-D and 2-D resistivitymeasurement while WinResist software and Dipro software were used for the processing respectively.The results of the vertical electrical sounding indicate that the depth to basement values ranges between 27.6 and 39.5m. The 2D resistivitysurvey has provided valuable information on the lateral and vertical variation of the layer competent for erecting foundation of engineering structures. The CPT probed an average depth of 4.8m and has identified material of very high shear strength associated with dense sand materials. The correlation of the three techniques used revealed similar soil layering consisting of topsoilsandy clay, coarse sand and sand.A mechanically stable coarse sand material was discovered as weathered layer which indicates high load bearing capacity suitable for foundation in the area and can support massive structures.
Subsurface 2D Image Analyses of the Uyangha Basement Area, South-Eastern NigeriaIOSR Journals
Geo-electric soundings were made in Stella Maris Secondary School, in Uyangha, Nigeria to image
the subsurface and obtain thicknesses and resistivities of different layers. A quantitative interpretation of the
data obtained clearly reveals the presence of four (4) geo-electric sections which are interpreted to be dry
laterite, moist laterite, weathered basement, and saturated basement. The depth probed is about 100m. The
saturated basement is the aquifer unit. Depth to aquifer unit in the area is at about 65m to 80m.The thickness of
the aquifer unit ranges from 20m to 35m. For ground water exploitation, boreholes in the area should therefore
be drilled to the depth of 91m, for reasonable groundwater yield. The lateritic layer makes the study area
suitable for building construction in the area.
Integrated Geophysical Studies Over Parts of Central Cross River State for th...iosrjce
A total of 71 Vertical Electrical Soundings were carried out using Schlumberger electrode
configuration for the evaluation of groundwater potential in parts of central Cross River State, Nigeria.
Interpretation of data showed three to six geoelectric layers. Productive shallow and deep aquifer zones were
identified at depths of 60 m and 150 m respectively, corresponding to a resistivity range of 100-500 Ωm for
shallow aquifers and 1000-2500 Ωm for deep aquifers respectively. The lithologic data of the aquifers revealed
sand/sandstone and very coarsed grained sand/fractured basement, respectively. Seismic refraction survey was
also carried out within the same study area for the foundation study of rocks. The studies revealed an average
thickness of 4.5 m (probably sand/clay) and 10.0 m (probably gravelly sand/shale) for the first and second
layers respectively. The range of velocities for the first three layers are 602 m/s to 960 m/s, 378 m/s to 2,424 m/s
and 1,587 m/s to 5,368 m/s, respectively, indicating that the soils in the area are not homogeneous. It is inferred
from the relative high values of calculated elastic constants in most of the locations, that the soils are well
consolidated and as such suitable for large engineering construction in such locations, while in the rest of the
locations the soils are considered unconsolidated and unsuitable for large construction work due to the relative
low values of the elastic constants.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Evaluation of sub-soil geo-electric properties in a proposed power sub-statio...IJERA Editor
Electrical resistivity survey was carried out in a site proposed for the construction and installation of a Power sub-station. The project will involve subsurface installation of cables and other objects that easily conduct electricity. Extant laws including EIA also require knowledge of subsurface distribution of resistivity in construction projects that would involve burial of steel pipes and cables. The imperative of this is emphasized by the location of the project in an area of shallow groundwater conditions. Field resistivity measurements were undertaken using ABEM Terrameter SAS 1000, adopting Schlumberger configuration in vertical electric sounding at 12 locations within the study site. The results were used to generate geo-electric log models. Three geo-electric profile models (pseudo- profiles) were also taken NE-SW of the site. Interpretation of the models shows that the area is characterized by two geo-electric layers to the depth of 30m. The upper layer of lower resistivity occurs to a depth of 2-3m. This layer consists of lateritic to silty sands. The lower layer has a resistivity of between 900 - >2000 Ωm and represents fine to coarse sands and gravels. On the Soil Electrical Resistivity Classification (BS 1377), the subsoil falls within non-corrosive class. Objects installed in the soil are not likely to suffer corrosion soon. Similarly, subsurface electrical installations will pose minimal hazards and would require basic precautions to avoid electrical accidents.
In order to solve the water scarcity problem in South Malang, East Java,
Indonesia, we have attempted to investigate groundwater by assessing the subsurface
geology and groundwater potential zones. An attempt had been made to identify the
subsurface lithology and aquifer zones by VES (Vertical Electrical Sounding) method
in Pagak, Kepanjen, Kromengan and Gondanglegi district. The study area consists of
major subsurface litho units like sand, silt, clay, tuff, limestone and andesit. In order
to explore the groundwater resources of the study area with an aerial extent of 100
km2, electrical soundings have been conducted by adopting Schlumberger technique
in 12 locations with AB/2 200 m and 5 resistivity profiles were acquired. The field
data were interpreted and processed qualitatively and quantitatively by using
computer software. Considering the geological, geomorphology and hydrogeological
conditions the VES interpretation was done. The study has shown that the region is
underlain by 5 geoelectric layers within the depth penetrated. The groundwater
potential in South Malang reveals four distinct classes (zones) representing ‘Very
good’, ‘good’, ‘moderate’ and ‘poor’ groundwater potential in the area. From the
interpretation result the VES no. 7 (Pagak), and VES no. 9 (Kepanjen) are found to be
prospective for groundwater. It’s also identified that Groundwater occurs under
water table conditions the depth of water table ranges from 5 to 30 m.
Eight Vertical Electrical Sounding surveys were carried out in Abua town in Rivers State, Nigeria to determine the depth to shallow aquifers suitable for borehole drilling for groundwater use in the town. The Schlumberger array method was employed with current electrode spread of 200 m to 600 m and the corresponding electric current and voltage measured. The apparent resistivity was obtained and plotted against half the current electrode spread with the aid of an IPWIN 12 software to obtain the field curves which were interpreted in terms of resistivity, thickness and depth of occurrence. The results revealed two to four geoelectric sections with resistivity values of 8.29 Ω to 777 Ω. The maximum depth penetrated was 56.5 m with the maximum current electrode spread used. A shallow aquifer close to the surface at Omelema waterside was observed with a thickness of 49 m. The abnormal resistivity value of this zone indicates that it was probably contaminated by saline water intrusion. At Abua LGA site, a shallow aquifer was also observed at a depth of 7.86 m. At the dump site, the shallow aquifer was contaminated by leachates while at Omelema primary school site the result revealed unconsolidated sediments. The results for Abua Amp site and Rghom site also revealed shallow aquifers at depths of 4 m and 6 m respectively.
Geoelectrical and Hydrochemical Assessment of Groundwater for Potability in E...Premier Publishers
Geoelectrical and hydrochemical investigations were carried in order to determine the potentials and quality of groundwater in Ebonyi North, Southeastern Nigeria. These methods were also selected to determine their economy and accuracy compared to seismic method. Fifteen (15) vertical electric sounding (VES) survey were conducted using the Schlumberger configuration in order to evaluate the character of the aquifers in the studied locations while twelve (12) groundwater samples were collected from boreholes for hydrochemical analysis. Geoelectric sections derived from modelling of the VES data with the interpex IX1D software reveal 3 to 5 subsurface layers. The lithologic succession comprises of topsoil, lateritic clay, partially weathered, weathered and fractured Asu River shale. The weathered and fractured layers constituted the productive water bearing or aquiferous zones of good groundwater potentials. Hydrochemical analysis of groundwater samples reveals that the pH range from 7.8 to 8.8, electrical conductivity from 10.0 to 1754.00 μS/cm, total dissolved solid from 10.0 to 786.0 mg/l and total hardness from 14.0 to 271.0 mg/l. The analytical results present the concentration of the ions in the following order: Mg > Ca > Na > K and Cl > SO4 >HCO3> NO3 > CO3. Piper trilinear diagram reveals only one water type, with Ca and Cl as the major dominant ions. The major ions concentrations are within recommended standard for drinking, hence the groundwater from the area is suitable for drinking and domestic purposes.
● Heavy Metal Emission Characteristics of Urban Road Runoff
https://ojs.bilpublishing.com/index.php/jees/article/view/1711
● Investigation of Geology and Hydro-geophysical Features Using Electromagnetic and Vertical Sounding Methods for Abu Zabad Area, Western Kordofan State, Sudan https://ojs.bilpublishing.com/index.php/jees/article/view/1279
● Power Spectrum in the Conductive Terrestrial Ionosphere
https://ojs.bilpublishing.com/index.php/jees/article/view/1763
● Thoughts on the Construction of Beautiful Villages with Poverty Alleviation in the Perspective
https://ojs.bilpublishing.com/index.php/jees/article/view/1615
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Investigation of Groundwater Potential and Aquifer Protective Capacity of Par...Premier Publishers
The aim of this study was to investigate groundwater potential and aquifer protective capacity of an area behind the College of Science, Federal University of Petroleum Resources, Effurun-Warri area of Delta State, Nigeria. The data was acquired using ABEM SAS 4000 Terrameter and processed using IPI2win and Interpex software. Five Vertical Electrical Soundings were carried out with maximum current electrode separation (AB) of 120 m. The VES curves generated from the data revealed HKH curve type for VES 1 and VES 2, KQH curve for VES 3 and KH curve for VES 4 and 5. Five resistivity layers were identified for VES 1 - 3 while four resistivity layers were identified for VES 4 – 5. Analysis and interpretation of VES data obtained from the study area showed VES 3, VES 4 and VES 5 to be most appropriate locations to be explored for borehole development due to low resistivity of the weathered/fractured aquiferous layers coupled with the relatively high thicknesses of the weathered layers. However, all the aquifers in the VES locations are poorly protected due to the very low aquifer protective capacity parameters in the VES locations.
Seismic Refraction Survey for Groundwater Potentials of Northern Paiko Area. ...iosrjce
This paper titled Seismic Refraction Survey for Groundwater Potentials of Southern Paiko Area.
Niger State, Nigeria, employs the service of seismic refraction survey method. A twelve-channel seistronix was
used for the data collection. The profiles were marked at 100 m intervals, while the profiles lines traversed
1000 m (1km). A Total of 44 spreads were shot. Data were collected, Time – distance (T-S) graphs were plotted
using matrix laboratory software, velocities of the underlying layers obtained and depths to the refractor layer
computed and geologic cross sections were obtained. The results obtained gave an overview of the lateral
variation in the lithological changes of the subsurface earth materials in the surveyed area. The basement
surface varied in depth, from 10.16 m to a maximum of 14.80 m. weathered layer velocities ranging from 809
m/s to 3612 m/s and consolidated layer velocities varying between 2858 m/s to 9696 m/s. Four shot points were
delineated as aquifer potentials of the area having depth to refractor varying between 13.70 m and 14.80 m with
overburden velocities ranging from 1940 m/s to 3462 m/s. The rock materials identified in the surveyed area are
chiefly sand, saturated clay, gravel, gneiss, igneous rock and granite.
Resistivity Imaging of Shallow Sediments within University of Maiduguri Campu...iosrjce
Electrical resistivity imaging within University of Maiduguri campus shows varying resistivity values
and thicknesses for shallow sediments from one profile line to another. Sequence stratigraphy of the sediments
indicates they were deposited at different times and varying conditions. Structure of the medium of deposition
conditioned the lithological structures of the sediments. Basin or bowl-shapes of some resistivity structures are
characteristics of some gravelly and clayey sediments. In most cases where such structures are encountered,
gravels seem to host sands; while clays are located at the central parts. This situation may suggest that the
sediments were deposited at the same time, where heavier ones settled to the bottom of the stratigraphy.
Sometimes clayey sediments host sandy sediments; a situation that may be associated with different times of
deposition. Some sediments were laid horizontally, some inclined and others nosed into overlying ones.
Majority of the resistivity images indicate clayey sediments occupying the basal resistivity units. Lower
resistivity values associated with some clayey sediment suggest high degree of saturation. The water might have
been derived through infiltration of the overlying porous sediments. The clays may be followed upwardly by
sands, while gravels sometimes form the capping sediments. Few resistivity profiles host the three sediments at
the bottom of the resistivity structures. Stratigraphic thicknesses for the sediments vary both laterally and
vertically. These are associated with the structure of the medium and prevailing conditions at the time of
deposition
Determination of Thickness of Overburden in Basement Area Using Schlumberger ...iosrjce
The overburden thickness of Abuja (Lat. 70
12´N – 9
0 30´ N and Long. 50
24´E- 7
0
19´E)
has been estimated. The geophysical method used was the electrical resistivity and the electrodes
array was Schlumberger type. The equipment utilized were four electrodes, hammer, four reels of
wires, crocodile clips, measuring tape, global positioning systems(GPS) and a terrameter. The survey
was carried out in two locations and the average resistivity values of the first four geoelectrical layers
were from the surface, 590 Ωm, 1800 Ωm, 1900 Ωm and 760 Ωm. These layers were interpreted as
probably top soil, laterite, weathered basement rock and fairly weathered basement rock. The
average thickness of the overburden was found to be 5.43m
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Subsurface Determination Of Cavities In Limestone Rock Area By Geoelectric Me...IJERA Editor
Two Dimensional of geoelectric method can be used to find out the conductive formation in the earth surface. The purpose of this research is to give the description about the geological subsurface formation, that the high resistivity value is indicate the potential area of cave and void in the limestone rocks. The dipole dipolegeoelectric method is used in this research with the path of lines is 250 m with 10 m electrode spacing. The total lines is 7 and the azimuth is from east to west. Resistivity method is started with inject the electrical current into the earth by current electrode, then potential difference will arise and measured by potential electrode. Variation value of resistance for each layer rock can calculated by divided potential defference with current value. The existence of the cavity is known by the resistivity value is more than 2500 ohm-m, while the cracks have a resistivity of 1500 to 2500 ohm-m.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Toxic effects of heavy metals : Lead and Arsenicsanjana502982
Heavy metals are naturally occuring metallic chemical elements that have relatively high density, and are toxic at even low concentrations. All toxic metals are termed as heavy metals irrespective of their atomic mass and density, eg. arsenic, lead, mercury, cadmium, thallium, chromium, etc.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...
Rmz 59-4 3
1. 363
RMZ – Materials and Geoenvironment, Vol. 59, No. 4, pp. 363–390, 2012
The groundwater potential evaluation at industrial estate
Ogbomoso, Southwestern Nigeria
Ocena potenciala podtalnice na industrijskem območju
Ogbomoso v jugozahodni Nigeriji
L. A. Sunmonu1, T. A. Adagunodo1, *, E. R. Olafis oye1 & O. P. Oladejo2
1Ladoke Akintola University of Technology, Department of Pure and Applied
Physics, P. M. B. 4000, Ogbomoso, Oyo State, Nigeria
2Emmanuel Alayande College of Education, Department of Physics, Oyo, Oyo
Original scientific paper
State, Nigeria
*Corresponding author. E-mail: taadagunodo@yahoo.com
Received: August 20, 2012 Accepted: November 4, 2012
Abstract: Vertical Electrical Sounding method was used to map Oyo
State industrial estate Ogbomoso with a view to determining the
groundwater potential of the study area. Ten Vertical Electri-cal
Soundings (VES) were carried out across the area using the
schlumberger electrode array configuration with current elec-trode
separation (AB) varying from 130 m to 200 m. Nine out
of the ten modeled curves were H-type where the remaining one
was KH-type. The geoelectric sections obtained from the sound-ing
curves revealed 3-layer and 4-layer earth models respec-tively.
The models showed the subsurface layers categorized
into the topsoil, weathered/clay, fractured layers and the fresh
bedrock. The weathered basement and fractured basement are
the aquifer types delineated for the area. Groundwater potential
evaluated from the maps (i.e. overburden thickness, anisotropic
coefficient, weathered layer isothickness, weathered layer isore-sistivity,
transverse resistance and bedrock relief maps) revealed
that the Southern and Eastern parts of the study area are the most
promising region for borehole development. However, North-eastern
region of the study area can also be considered as fair for
borehole development.
2. 364 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
Izvleček: Z metodo vertikalnega električnega sondiranja so kartirali
industrijsko območje države Oyo Ogmoboso v Nigeriji z name-nom
opredeliti potencial podtalnice. Opravili so sedem vertikal-nih
električnih sondiranj (VES) s Schlumbergerjevo razporedi-tvijo
elektrod in razdaljami med tokovnima elektrodama (AB)
od 130 m do 200 m. Devet izmed desetih modeliranih krivulj je
bilo vrste H, preostala pa vrste KH. Geoelektrični profili, izde-lani
po krivuljah sondiranja, razkrivajo triplastne in štiriplastne
modele. Zastopane so plasti vrhnjega nivoja tal, preperine/gli-ne,
razpokane kamnine in nepreperele kamnine. Vodonosnika
na preiskovanem ozemlju sta v prepereli podlagi in razpokani
podlagi. Potencial podzemne vode, ocenjen po izdelanih kartah
(debeline pokrova, koeficienta anizotropnosti, navidezne debe-line
in navidezne upornosti in reliefa preperinske plasti), kaže,
da so najperspektivnejši za vrtanje južni in vzhodni deli razi-skovanega
območja. Potencial vode v severovzhodnem delu je
RMZ-M&G 2012, 59
Introduction
The importance of groundwater as a
supply source to the socio-economic
development of a country is tremen-dous.
Though, the state water corpo-rations
make use of some minor riv-ers
as a means of water supply to the
populace especially in the urban areas
but this water is insufficient for do-mestic
uses let alone its availability
for industrial uses. Constant supply of
water cannot be denied in any indus-trial
settings, as it serves as one of the
amenities to be available in industries.
Therefore, groundwater has proved it-self
to be the only available source of
water for industrial uses.
The use of geophysics for both ground-water
resource mapping and for water
quality evaluations has increased dra-matically
over the years. The Vertical
Electrical Soundings (VES) has proved
very popular with groundwater stud-ies
due to simplicity of the technique.
ocenjen kot povprečen.
Key words: vertical electrical sounding, groundwater potential, frac-tured
basement, thick overburden, aquifer, industrial estate
Ključne besede: vertikalno električno sondiranje, potencial podtal-nice,
razpokana podlaga, debel pokrov, vodonosnik, industri-jska
lokacija
3. The groundwater potential evaluation at industrial estate Ogbomoso, ... 365
Groundwater has become immensely
important for human water supply in
urban and rural areas in developed and
developing nations alike (Omosuyi,
2010). Using this method, depth and
thickness of various subsurface layers
and their water yielding capabilities
can be inferred. Therefore, evaluation
of groundwater potential at industrial
estate Ogbomoso was done in order to
know the groundwater yielding capa-bilities
or groundwater conditions of
the study area. In basement complex,
unweathered basement rocks contain
negligible groundwater. Significant
aquifers however, develop within the
weathered overburden and fractured
bedrock. This research is particular
to know feasibility of potable water
borehole in the industrial estate (i.e. to
know the promising areas for ground-water
prospects within the study area).
This was done in order to advise the
building engineers and the users of
the estate not to build factories, ware
houses or administrative buildings on
the available zones for groundwater
exploration and to know the promising
zones for groundwater exploration in
the study area. However, the ground-water
conditions of industrial estate
when properly understood could be
used as an effective tool in the plan-ning
of reliable water borehole in the
study area.
The study area is underlain by Precam-brian
rocks of the Nigerian Basement
RMZ-M&G 2012, 59
Complex where aquifers are both iso-lated
and compartmentalized. These
rocks in their deformed state posses lit-tle
or no primary intergranular porosity
and permeability and thus the occur-rence
of groundwater is due largely to
the development of secondary porosity
and permeability by weathering and/
or fracturing of the parent rocks (Ac-worth,
1987; Olorunfemi & Fas uyi,
1993; Olayinka et al, 1997). Ground-water
localization in this region is con-trolled
by a number of factors which
include the parent rock type, the depth,
extent and pattern of weathering,
thickness of weathered materials, and
the degree, frequency and connectivity
of fracturing, fissuring and jointing, as
well as the type and nature of the fill-ings
in the joint apertures (Oluyide a&
Udey, 1965; Bia nchi & Snow, 1969;
Ass eez, 1972; Odusa nya, 1989; Esu,
1993; Eduvie & Olabode, 2001).
Considering the limited characteris-tics
of the groundwater reservoirs in
the Basement Complex, the full ben-efit
of the aquifer system can only be
exploited through a well coordinated
hydrogeophysical and geological in-vestigation
program of the prospec-tive
area. Geoelectrical techniques are
powerful tools and play a vital role in
groundwater investigations particu-larly
in the delineation of the aquifer
configuration in complex geological
environments. A planned geoelectrical
investigation is capable of mapping an
4. 366 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
aquifer system, clay layers, the depth
and thickness of aquifers, fissure or
fracture location, and qualitatively es-timating
local groundwater flow (Fit -
terma n & Stewart, 1986; McNeill,
1987; Olas ehinde, 1989) and has been
adopted in this study. The most com-monly
used geophysical technique for
groundwater exploration is electrical
resistivity (Mazac et al, 1987) which
is aimed at identifying high conductiv-ity
anomalies, normally thought to be
due to deep weathering. Recent devel-opments
in geoelectrical data acquisi-tion
and interpretation methodology
provide electrical images of subsurface
features. A properly calibrated electri-cal
image can be used to infer the aq-uifer
configuration: depth, thickness,
horizontal and vertical extent of the
aquifers. Investigation involving detail
geophysical study for groundwater po-tential
in the area covered by this study
is presently non-existence. This exi-gency
inspired this study. Therefore,
the primary objective of this study was
to determine the groundwater potential
and to identify suitable sites/locations
for exploration of groundwater in in-dustrial
estate Ogbomoso, Southwest-ern
Nigeria.
Site description
The studied area lies within the crys-talline
Basement Complex of Nigeria
(MacDonald & Davies, 2000). It lies
within latitude 080 06′ 07.4″ and 080 06′
25.4″ and longitude 0040 15′ 03.3″ and
0040 15′ 49.0″. The study area is locat-ed
at the outskirt of Ogbomoso South
Local Government and shares bound-ary
with Surulere Local Government
Area along old Oshogbo road. The
study area is accessible with network
of roads that surrounds it and very
close to Aarada market.
Hydrogeological setting
According to MacDonald & Davies
(2000) who classified the hydrogeol-ogy
of Sub-Saharan Africa into four
provinces, these are: Precambrian
basement rocks, volcanic rocks, uncon-solidated
sediments and consolidated
sedimentary rocks (figure 1a). These
four provinces Nigeria (figure eare well represented in
1b). The study area is
located on the Precambrian basement
rocks of Southwestern Nigeria which
comprise of crystalline and metamor-phic
rocks over 550 million years old
(MacDonald & Davies, 2000).
Unweathered basement rock contains
negligible groundwater. However, sig-nificant
aquifers develop within the
weathered overburden and fractured
bedrock (MacDonald & Davies, 2000;
Alagbe, 2005). In the soil zone (top
soil) of Precambrian basement, perme-ability
is usually high, but groundwater
does not exist throughout the year and
5. The groundwater potential evaluation at industrial estate Ogbomoso, ... 367
dries out soon after the rains end. Be-neath
the soil zone, the rock is often
highly weathered and clay rich, there-fore
permeability is low. Towards the
base of the weathered zone, near the
fresh rock interface, the proportion of
clay significantly reduces. This hori-zon,
which consists of fractured rock,
is often permeable, allowing water to
move freely. Wells or boreholes that
penetrate this horizon can usually pro-vide
sufficient water for consumption
(MacDonald & Davies).
Deeper fractures within the basement
rocks are also an important source
of groundwater, particularly where
the weathered zone is thin or absent.
These deep fractures are tectonically
controlled and can sometimes provide
supplies of up to 1 l/s or even 5 l/s. The
groundwater resources within the reg-olith
and deeper fracture zones depend
on the thickness of the water-bearing
zone and the relative depth of the wa-ter
table. The deeper the weathering,
the more sustainable the groundwater
(MacDonald & Davies, 2000).
Geological setting
Regionally, the Study area lies within
the South Western parts of the Base-ment
rocks, which is part of the much
larger Pan-Africa mobile belt that lies
in between the West Africa Craton and
Congo Craton, suspected to have been
RMZ-M&G 2012, 59
subjected only to a thermotectonic
event (Alagbe, 2005).
In general, the southwestern Nigeria
crystalline Basement (figure 1c) can be
grouped into three:
• The Migmatite-Gneiss Com-plex:
It compose of Migmatite and
gneiss of various composition. Rel-ics
of sedimentary rocks such as
quartzitic rocks occurring within
the group with ages ranging from
Pan-Africa (600 million years) to
Leonian (Russ, 1957).They have
been metamorphosed in the mid-dle
to upper amphibolite facies
(Ajibade et al, 1988).
• Metasedimentary and Metavol-canic
Rocks: (This is also known
as Low grade sediment dominated
schist belt) trending N-S which are
considered to be Upper Proterozoic
(Birimian) in age. The Northwest-ern
basement has well developed
schist belts(Green Schist facies)
comprising mainly of phyllite,
Schist, quartzitic and banded iron
formation(BIF).The rocks are con-sidered
to be Upper Proterozoic
that has been infolded into Migma-tite-
gneiss complex (Truss well &
Cope, 1963).
• The Pan-African Older Granite
Series: This intrude both into the
Migmatite-gneiss-quartzite com-plex
and the Low grade schist belts.
They range widely in age and com-position
from true granite to grano-
6. 368 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
diorite, adamalite and tonalities.
Other rocks associated with it are
highly hypersthenes bearing rocks
called charnokites.
Their Rb/Sr ages range between
750 million years and 450 million
years(Ajibade et al 1988), which are
considered to be ages of emplacement,
classify these rocks as strictly belong-ing
to Pan Africa. Notably among
the granite series are Kusheriki gran-ites
(Truswell & Cope, 1963). The
above three division is largely based
on lithology and does not in anyway
reflect the range of Complex field re-lationship
and structures displayed on
the rocks.
Locally, the study area lies within
Ogbomoso and is underlain by rocks
of the Precambrian complex with
Quartzite and Quartz-Schist and Un-differentiated
Gneiss and Migma-
Figure 1a. The hydrogeological domains of Sub-Saharan Africa (MacDonald &
Davies, 2000).
7. The groundwater potential evaluation at industrial estate Ogbomoso, ... 369
tite (Ajibade et al., 1988). The rock
groups in the area include quartzites
and gneisses (Ajibade et al, 1988).
Schistose quartzites with micaceous
minerals alternating with quartzo-feldsparthic
ones are also experienced
in the area. The gneisses are the most
dominant rock type. They occur as
granite gneisses and banded gneisses
with coarse to medium grained tex-ture.
Noticeable minerals include
quartz, feldspar and biotite. Pegma-tites
RMZ-M&G 2012, 59
are common as intrusive rocks
occurring as joints and vein fillings
(Rahaman, 1976; Ayantunji, 2005).
They are coarse grained and weath-ered
easily in to clay and sand-sized
particles, which serve as water-bear-ing
horizon of the regolith. Structural
features exhibited by these rocks are
foliation, faults, joints and microfolds
which have implications on ground-water
accumulation and movement
(Ayantunji, 2005).
Figure 1b. The hydrogeological domains of Nigeria (extracted from MacDonald &
Davies, 2000).
8. 370 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
Figure 1c. Geological map of Nigeria showing the study area. (Modified after Ajibade
et al, 1988).
AB MN
(( 2 2
RMZ-M&G 2012, 59
Theory of electrical resistivity in
rocks
The foundation of electrical resistiv-ity
theory is the Ohm’s law (Grant &
West , 1965) which states that the ratio
of potential difference (V) between two
ends of a conductor in an electrical cir-cuit
to the current (I) flowing through
it is a constant.
V = IR (1)
Where R is a constant known as resist-ance
measured in ohms (Ω).
If the conductor is a homogeneous cyl-inder
of length (L) and cross sectional
area (A), the resistance will be propor-tional
to the length and inversely pro-portional
to the area (Duffin, 1979).
ρL
R = (2)
A
Where 2πr2
ρ is the resistivity measured in
ohm-meter (Ωm).
ΔV = ∫ E.dr.
The earth’s material is predominantly
made up of silicate, which are basi-cally
V I
ρ
2
Δ =
non-conductors. The presence of
r
π
water in the pore spaces of the soil and
in the ρ rocks = ΔV.enhances 2πr
the conductivity
of the earth when an electrical current
(I) is passed Δ
through it, thus making
the rock ρ =
V
.
G
a a semi-I
conductor.
If the electrical field generated by the
current is E across the length when a
potential difference (V) is applied, then
the potential difference can be defined
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
ρ < ρ > ρ < ρ
9. ρ
2
The groundwater potential evaluation at industrial estate Ogbomoso, ... 371
(Evwaraye & Mgbana, 1993) as:
V = EL (3)
where E is the electric field strength
with dimension of volt per meter
(V/m).
If the current electrode is taken to pen-etrate
a small hemisphere of radius r,
then the area of the hemisphere be-comes
ρL
ρL
2πr2.
ρL
A
Substituting for E and integrating
Equation 3 gives:
2πr2
ΔV = ∫ E.dr.
(Duffin, 1979) (4)
ρ
2
ρ
2
ρL
or ρ
(5)
2
and (6)
Since the Δ
Δ
earth V
V
is not homogeneous,
Equation Δ
V
6 is used to define an appar-ent
resistivity ρa which is the resistivity
AB MN
ρ
2
the earth would have if it were homo-geneous
AB MN
(( 2 2
(( 2 2
AB MN
(Grant & West , 1965). Equa-tion
(( 2 2
6 can be written in a general form
as:
AB MN
(( 2 2
n
h h
Σ Σ
n
h h
Σ Σ
n
h h
ρ
Σ Σ
V
Δ
ρ
t
ρ
t
t
RMZ-M&G 2012, 59
(7)
where G is a geometrical factor fixed
for a given electrode configuration.
The schlumberger electrode configura-tion
has been used in this study. i i
In this
i i
arrangement, current is i injected i
into the
earth through two electrodes which cre-ate
a potential field which is detected by
another pair of electrodes. The geomet-rical
V
Δ
factor for the schlumberger elec-trode
configuration is given by:
(8)
AB MN
(( 2 2
where AB is the distance between two
current electrodes, and MN is the dis-tance
between two potential difference.
Materials and methodology
Σ Σ
n
h h
A four ρ
day t
geophysical i survey i
was car-ried
out from 13th to 16th October, 2011
using the electrical resistivity method.
The survey was conducted with R 50
Resistivity meter. A total of 10 Verti-cal
Electrical Sounding (VES) stations
were occupied randomly to cover the
area of study (Figure 2). The schlum-berger
array with maximum electrode
spacing (AB) of 130 m to 200 m was
used for the field resistance measure-ments.
The resistivity values were de-termined
and plotted on a double loga-rithmic
graph paper for quick check on
the field. The VES curves were gener-ated
by applying the conventional curve
matching (Zohdy, 1973; Zohdy & Ma-boy,
1974; Patra & Nath, 1999).
Parameters such as apparent resistiv-ity
and thickness obtained from par-tial
curve matching were used as input
data for computer iterative modeling
A
2πr2
ΔV = ∫ E.dr.
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
2
1
1
1
1
1
1
(Σ −
)
=
−
=
−
= = = n
i
i
i
n
i
i i
l
h
ρ
ρ
ρ
λ
T T T = K × R = Kσ × R
ρ
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
2
1
1
1
1
1
1
(Σ −
)
=
−
=
−
= = = n
i
i
n
i
i i
l
h
ρ
ρ
ρ
λ
T T T = K × R = Kσ × R
ρ
A
2πr2
ΔV = ∫ E.dr.
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
2
1
1
1
1
1
1
(Σ −
)
=
−
=
−
= = = n
i
i
i
n
i
i i
l
h
ρ
ρ
ρ
λ
T T T = K × R = Kσ × R
ρ
A
2πr2
ΔV = ∫ E.dr.
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
n
Σ −
1
Σ
−
1
i
n
h i i
h
ρ
ρ
ρ
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
2
1
1
1
1
1
1
(Σ −
)
=
−
=
−
= = = n
i
i
i
n
i
i i
l
h
ρ
ρ
ρ
λ
T T T = K × R = Kσ × R
ρ
10. 372 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
using the WinResist software (Vander
Velpen, 2004). The VES curves gener-ated
gives the thickness and the resis-tivities
of different layers. The depth
sounding curves were then classified
according to the resistivity contrasts
between the layers as H, K, A, Q or
multiples thereof, following the clas-sification
by Keller & Fris chnecht
(1970) and Patra & Nath (1999). The
modeling produced series of curves as
shown in figure 3(a–b). Nine out of the
ten curves were H-type (ρ1 > ρ2 < ρ3)
while the remaining one showed KH-type
(ρ1 < ρ2 > ρ3 < ρ4). Surfer 8 soft-ware
(Surfer 8, 2002) was further used
on personal computer to produce 3-di-mensional
view of Overburden isopach
map, overburden anisotropic coefficient
map, weathered layer isothickness map,
weathered layer isoresistivity map,
weathered layer transverse resistance
map, and bedrock relief map in order
to evaluate the groundwater potential
of the study area. Surfer 8 program is
software that helps to produce 2-Di-mensional
and 3-Dimensional images.
Geoelectric layers parameters was input
into this software to produce 3-Dimen-sional
images of subsurface in order to
determine the groundwater potential of
industrial estate Ogbomoso.
Figure 2. Layout map of Vertical Electrical Sounding stations.
11. The groundwater potential evaluation at industrial estate Ogbomoso, ... 373
Results and discussion
The presence of groundwater in any
rock presupposes the satisfaction of two
factors: adequate porosity and adequate
permeability. On account of their crys-talline
nature, the metamorphic and ig-neous
rocks of the Basement Complex
satisfy neither of these requirements.
Basement complex rocks are thus con-sidered
RMZ-M&G 2012, 59
to be poor aquifers because of
their low primary porosity and perme-ability
necessary for groundwater ac-cumulation
(Davis & De Weist, 1966).
However, secondary porosity and per-meability
imposed on them by fractur-ing,
fissuring, jointing, and weathering
through which water percolates make
them favourable for groundwater stor-age
(Omorinbola, 1979).
Figure 3(a). The modeled curve for VES 1 to VES 6
12. 374 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
Figure 3(b). The modeled curve for VES 7 to VES 10.
The modeled curves showed three
layers in nine of the VES stations
(i.e. VES 1, 2, 3, 4, 5, 6, 7, 9 and 10)
and four layers in the remaining one
(i. e. VES 8) (figure 3a–b). The result
showed that 60 % of the VES stations
have thin overburden and fresh base-ment
rocks (i.e. VES 1, 3, 4, 5, 7 and
10), 20 % of the VES stations have
thick overburden and fresh basement
rocks (i.e. VES 8 and 9) while the
remaining 20 % of the VES stations
have thick overburden and fractured
basement rocks (i. e. VES 2 and 6).
From the results, VES 2 and 6 are
the best location for groundwater
prospect because of the thick over-burden
and fracture in the basement
(Wright, 1990; Meju et al., 1999).
VES 8 and 9 could be considered
as another location for groundwa-ter
exploration because Benson
& Jones (1988) and Lenkey et al.
(2005) reported that boreholes
should be sited where the regolith
is thickest.
Summary of the formation of
the layer parameters is present-ed
in table 1 while summary of
classification of the resistivity
sounding curves is presented in
table 2.
13. The groundwater potential evaluation at industrial estate Ogbomoso, ... 375
Table 1. Summary of the formation of layer parameters.
Groundwater Potential Evaluation
The groundwater potential of a base-ment
complex area is determined by
a complex inter-relationship between
the geology, post emplacement tecton-ic
history (fractures), weathering pro-cesses
and depth, nature of the weath-ered
layer, groundwater flow pattern,
recharge and discharge processes
(Olorunfemi et al, 1999). The ground-water
potential of the study area was
evaluated based on maps (i.e. overbur-den
thickness, anisotropic coefficient,
weathered layer isothickness, weath-ered
layer isoresistivity, transverse
resistance and bedrock relief maps)
generated from the VES interpretation
RMZ-M&G 2012, 59
results. The characteristic geoelectric
parameters enabled the groundwater
potential rating at each VES location.
These maps are as presented below.
Overburden Thickness Isopach Map
The depth to the basement (overburden
thickness) beneath the sounding sta-tions
were plotted and contoured at 1m
interval as shown in figure 4. This was
done to enable a general view of the
aquifer geometry of the surveyed area.
The overburden is assumed to include
the topsoil, the lateritic horizon and the
clay/weathered rock. The values range
from 4.4 m to 21.1 m. Areas with thick
overburden corresponding to basement
Location
Layer 1 Layer 2 Layer 3 Layer 4
r1/(Ω m) h1/m r2/(Ω m) h2/m r3/(Ω m) h3/m r4/(Ω m) h4/m
VES 1
VES 2
VES 3
VES 4
VES 5
VES 6
VES 7
VES 8
VES 9
VES 10
400.3
222.2
280.7
197.8
190.3
215.4
100.4
230.9
228.1
220.1
2.6
2.3
1.8
2.2
4.5
2.3
2.0
3.0
1.4
2.3
100.7
90.4
61.5
50.2
86.5
41.8
76.0
988.4
30.4
100.1
6.5
18.8
7.9
4.1
4.8
17.0
2.4
5.5
18.1
6.9
95835.0
606.4
2160.8
4580.4
1830.7
271.8
4344.4
128.5
6781.7
4036.2
-------
9.0
--
-------
14522.8
--
----------
Table 2. Classification of the resistivity sounding curves.
Curve types Resistivity model Model frequency VES Locations
H
ρ> ρ< ρ1 2 3
KH
ρ< ρ> ρ< ρ1 2 3 4
Total
91
10
1, 2, 3, 4, 5, 6, 7, 9, 10
8
14. 376 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
depression and are known to have high
groundwater potential particularly in
the basement complex area (Wright,
1990; Olorunfemi & Okhue, 1992;
Meju et al., 1999).
The Southern (i. e. VES 6), Northeast-ern
(i. e. VES 8 and VES 9) and East-ern
(i. e. VES 2) side of the study area
has thick overburden thickness while
the Western and Southeastern side of
the study area showed thin overburden
thickness. The Southern, Northeastern,
and the Eastern side of the study area
are the promising locations for ground-water
prospect.
Since the yield of a well in the Base-ment
Complex is expected to have
a positive correlation with the depth
Table 3. Aquifer potential as a function of the depth to bedrock (Olayinka et al., 1997).
Overburden Thickness (m)
Range Weighting
<5 2.5
5–10 5
10–15 7.5
>15 10
Figure 4. Overburden thickness isopach map
15. ΔV = ∫ E.dr.
V I
ρ
2
The groundwater potential evaluation at industrial estate Ogbomoso, ... 377
r
π
Δ =
to ρ = bedrock, ΔV.2πr
weights that are directly
proportional to the overburden thick-ness
V
Δ
have been assigned (Olayinka et
G
I
a .
ρ =
al., 1997). These weights range from a
minimum of 2.5 for thickness less than
5 m to a AB maximum MN
of 10 for overbur-den
(( 2 2
) )
2
) −
(
2
π
thickness exceeding 15 m (table 3).
MN
)
2
2(
G
=
Coefficient of Anisotropy of the Over-burden
The overburden’s coefficient of anisot-ropy
1 2 3 ρ > ρ < ρ
(λ) was calculated for each VES sta-tion
using the layer resistivities and thick-nesses
(Olorunfemi & Okhue, 1992);
1 2 3 4 ρ < ρ > ρ < ρ
1
−
h h
−
n
n
Σ Σ
i
ρ
i i
ρ
i i
1
(Σ )
i
ρ
= = = n
i
t
ρ
l
λ
T T T = K × R = Kσ × R
ρ
RMZ-M&G 2012, 59
(9)
where ρt is the transverse resistance,
ρl is the longitudinal resistance, i is
the summation limit varying from 1
to n – 1, hi is the ith layer thickness
and ρi is the i-th layer resistivity.
The λ values were plotted and con-toured.
This was done in order to know
the areas that are good for groundwa-ter
prospects. Areas which show ridges
on the map will be promising zones
for groundwater prospects while areas
which show depressions on the map
will not be suitable for groundwater
prospects. The resulting overburden
coefficient of anisotropy map (figure
5) shows λ values ranging from 1.0 to
1.45 with a mean value of 1.16. Viv-idly,
the Northeastern and to the base
1
1
2
1
−
1
=
=
h
i
Figure 5. Overburden anisotropy coefficient map.
16. 378 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
Table 4. Aquifer potential as a function of overburden anisotropic coefficient.
Anisotropy Coefficient (λ)
Range Weighting
<1 2.5
1–1.5 5
1.5–2 7.5
>2 10
RMZ-M&G 2012, 59
of the Eastern side of the study area
showed that overburden’s coefficient
of anisotropy (λ) is high. Also, some
peaks were observed at Southern to the
Southwestern part of the study area.
These areas with peaks are the prom-ising
locations for groundwater pros-pect.
Olorunfemi et al, (1991) gives the
mean coefficient of anisotropy of ig-neous
and metamorphic rocks of the
Basement Complex of southwestern
Nigeria as 2.12 and 1.56 respectively
and that groundwater yields increase
linearly with increase in λ (Olorun-femi
& Olorunniwo, 1985; Olorun-femi
et al, 1991; Olorunfemi & Okhue,
1992). All the values of λ obtained fall
within the range of areas underlain by
metamorphic rocks in the southwest-ern
Nigeria.
Since the yield of a well in the Base-ment
Complex is expected to have a
positive correlation with the value of
the overburden anisotropic coefficient,
weights, ranging from a minimum of
2.5 for λ less than 1 to a maximum
of 10 for λ exceeding 2 have been as-signed
(table 4).
Weathered Layer Isothickness Map
The weathered layers as defined in
this work are materials constituting
the regolith, straddled in between the
topsoil or laterite and fractured or fresh
bedrock. The thickness of these litho-logical
materials varies between 2.4 m
and 18.8 m. This was determined from
the layer interpretation of the sounding
results. The weathered layer isopach
map was produced using a contour
interval of 1 m (figure 6). The map
was produced with a view to observ-ing
how the weathered basement layer
considered to be the major component
of the aquifer in the study area varied
from place to place.
The weathered layer is seen to be
thickest at Eastern, some part of the
Northeastern region and Southern part
of the study area, groundwater poten-tial
is most prominent here. The West-ern
and peak of the Southeastern part
of the study area showed a very thin
weathered layer.
17. The groundwater potential evaluation at industrial estate Ogbomoso, ... 379
Weathered Layer Isoresistivity Map
In order to have an insight to the
groundwater potentials of the study
area, an aquifer resistivity map (fig-ure
7) was produced from the inter-preted
VES data results of this work.
The resistivity value of the aquifers
at each VES site location was plotted
and contoured at 5 Ω m. The map was
produced in order to distinguish high
water-bearing weathered layer from
low water-bearing ones, and to find out
whether or not the degree of weath-ering
/saturation varies from point to
point in the study area.
As shown on the map, the resistivity
value of the aquifer is highest at the
RMZ-M&G 2012, 59
Northeastern (i. e. VES 8 and VES
9) part of the study area which falls
within medium potential condition (ta-ble
5). However, the Southern part (i.
e. VES 6) and the Western part (i. e.
VES 4) of the study area showed low
resistivity values. The Southern part
might be the most promising location
for groundwater prospect because of
the results from VES curve 6 (Wright,
1990; Meju et al., 1999). The Western
part (i.e. VES 4) could be considered
as another promising area for ground-water
prospect but because of its thin
overburden (Lenkey at al., 2005), the
water present in the aquifer might not
be able to serve the industrial purposes
in the time of prolonged dry season.
Figure 6. Weathered layer isothickness map
18. 380 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
The electrical resistivity of the sap-rolite
layer overlying the basement
is controlled by the parent rock type,
climatic factors, as well as the clay
content. A low resistivity of the or-der
of less than 20 Ω m is indicative
of a clayey regolith (Carruthers &
Smith, 1992; Olayinka et al, 1997).
This reduces the permeability and
thus lowers the aquifer potential.
Weights are assigned to the weath-ered
layer resistivity values accord-ing
to Wright, (1992). Table 5 sum-marized
the optimum aquifer poten-tials
associated with the saprolite
resistivities.
Figure 7. Weathered layer isoresistivity map
Table 5. Aquifer potential as a function of the weathered layer resistivity (modified after
Wright, 1992).
Weathered Layer Resistivity (Ω m)
Range Aquifer Characteristics Weighting
<20 Clay with limited potential 7.5
21–100 Optimum weathering and good groundwater potential 10
101–150 Medium conditions and potential 7.5
151–300 Little weathering and poor potential 5
>300 Negligible potential 2.5
19. The groundwater potential evaluation at industrial estate Ogbomoso, ... 381
ρL
Weathered Layer Transverse Resist-ance
Map
Aquifer transmissivity has been found
to be a very powerful means of con-firming
zones of prolific aquifers. This
ρ
2
parameter is defined in hydrogeology,
as the product of aquifers hydraulic
conductivity (or permeability) and its
thickness.
T = K × h (10)
where Δ
T V
is transmissivity, K is hydrau-lic
conductivity and h is the thickness
of the aquifer (Todd, 1980).
(( AB 2 MN
2
According to Mai llet, 1974 transverse
resistance (R) of a layer as of the Dar-
TZarrouk parameters, is defined as:
R= h × ρ (11)
T Where, h and ρ are thickness and resis-tivity
respectively, of the layer.
The relationship between transmissiv-ity
(T) and transverse resistance (RT) is
meaningful, simply because hydrau-lic
n
h h
Σ Σ
ρ
conductivity t
(K) and i resistivity i
(ρ)
have a direct linear relationship (Niwas
& Singhal, 1981). Combining the two
equations, we have
RMZ-M&G 2012, 59
(12)
This relationship is suitable for de-termination
of aquifer transmissivity,
as the ratio K/ρ = Kσ is assumed to
be constant in areas with similar geo-logic
setting and water quality (Niwas
& Singhal, 1981; Aderinto, 1986;
Onuoha & Mbazi, 1988; Onu, 2003).
Thus knowing the value of K for some
existing boreholes and the value of σ
extracted from the sounding interpre-tation
for the aquifers at the borehole
locations, the transmissivity of the aq-uifer
can be computed.
These established relationships were
utilized with the hydraulic conductiv-ity
(K) values of boreholes near North-western
side (i.e. some metres away
from VES 10), near Northeastern side
(i. e. some metres away from VES 9),
and the other two boreholes were lo-cated
towards the Southern part of the
study area (i. e. behind the Civil de-fence
office). The hydraulic conduc-tivity
(K) were determined to be (6.62,
11.99, 11.42 and 15.54) m/d respec-tively
after pumping test by D’ Strata
Drilling Company and the Kσ of these
points were found to be 0.097, 0.097,
0.1164 and 0.1034 respectively. An
average of 0.10344 was used for the
entire study area. The transmissivity
at each VES station was determined
by multiplying average Kσ with corre-sponding
transverse resistance, RT and
the variation of transmissivity across
the aquiferous zone of the investigated
area is shown in figure 8.
On a purely empirical basis, it can be
admitted that the transmissivity of an
aquifer is directly proportional to its
transverse resistance (Henriet, 1975).
Therefore, transverse resistance maps
is used in determination of zones with
A
2πr2
ΔV = ∫ E.dr.
r
V I
π
Δ =
ρ = ΔV.2πr
G
I
a .
ρ =
)
2
2(
) )
2
) (
2
MN
G
−
=
π
1 2 3 ρ > ρ < ρ
1 2 3 4 ρ < ρ > ρ < ρ
2
1
1
1
1
1
1
(Σ −
)
=
−
=
−
= = = n
i
i
i
n
i
i i
l
h
ρ
ρ
ρ
λ
T T T = K × R = Kσ × R
ρ
20. 382 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
high groundwater potential (Toto et al,
1983: Braga et al, 2006) and suitable
for drilling wells.
The Eastern flank of the study area has
transverse resistance corrensponding
to high transmissivity which in turn
means greater water potential. Also, a
little peak is experienced at the South-ern
part of the study area, this location
is another promising area for ground-water
prospect in the study area. How-ever,
the Western and the Southeastern
flank generally has low transmissivity.
On a purely empirical basis, it can be
admitted that the transmissivity of an
aquifer is directly proportional to its
transverse resistance (Henriet, 1975;
Hadi, 2009). Hence, there exists a lin-
Figure 8. Weathered layer transverse resistance map.
Table 6. Aquifer potential as a function of the weathered layer transverse resistance.
Transverse Resistance (Ω m2)
Range Weighting
<400 2.5
400–1000 5
1000–2000 7.5
>2000 10
21. The groundwater potential evaluation at industrial estate Ogbomoso, ... 383
ear relationship between groundwater
potential and the transverse resistance
of an aquifer (Aderinto, 1986). Table
6 gives a summary of the variation of
aquifer potential with transverse resist-ance.
Bedrock Relief Map
The bedrock relief map (figure 9) is
a contoured map of the bedrock ele-vations
beneath all the VES stations.
These bedrock elevations were ob-tained
by subtracting the overburden
thicknesses from the surface eleva-tions
at the VES stations. The bedrock
relief map generated for the locations
shows the subsurface topography of
the bedrock across the surveyed area.
Bedrock relief map helps to see viv-idly
the suspected areas for ground-water
prospects. Areas with basement
depressions on the map serve as col-lecting
trough for groundwater which
will be the best zones for groundwa-ter
prospects. Bedrock relief has been
used by Okhue & Olorunfemi (1991),
Olorunfemi & Okhue (1992), Dan–
Hassan & Olorunfemi (1999), Olo-runfemi
et al, (1999) and Bala & Ike
(2001) to investigate into groundwa-ter
prospects at Ile- Ife SW, Kaduna
North Central, Akure SW and Gu-sau
NW part of Nigeria respectively.
Procedures used by them have been
adopted under this subsection in order
to get the promising areas for ground-water
prospects at Industrial Estate
Ogbomoso SW Nigeria.
RMZ-M&G 2012, 59
The map shows series of basement
lows/depressions and basement
highs/ridges. Southern, Eastern and
Northeastern part (i. e. VES 2, 6, 8
and 9) are the designated areas for
the depressions while Northwestern,
Western, Southwestern and South-eastern
part (i. e. VES 1, 3, 4, 5 and
7) are ridges zones. The depression
zones are noted for thick overburden
cover while the basement high/ridge
zones are noted for thin overburden
cover. Omosuyi & Enikanselu (1999)
findings revealed that depressions
zone in the basement terrain serves
as groundwater collecting trough
especially water dispersed from the
bedrock crests. Thus, the zones with
basement depressions are priority ar-eas
for groundwater development in
the study locations.
If the bedrock has a low resistivity,
a high aquifer potential could be
inferred as result of expected high
fracture permeability. Bedrock re-sistivities
of the study area from fig-ure
3a–b are as given below: VES
1 = 95835.0 Ω m, VES 2 = 606.4 Ω
m, VES 3 = 2160.8 Ω m, VES 4 =
4580.4 Ω m, VES 5 = 1830.7 Ω m,
VES 6 = 271.8 Ω m, VES 7 = 4344.4
Ω m, VES 8 = 14522.8 Ω m, VES 9
= 6781.7 Ω m and VES 10 = 4036.2
Ω m. The maximum weight of 10 is
therefore assigned to cases where
the resistivity of the bedrock is less
than 750 Ω m. As the resistivity of
22. 384 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
the bedrock increases, there would
be a reduction in the influence of
weathering, with a correspond-ing
lowering of the aquifer poten-tial
(Olayinka et al, 1997). Table 7
gives a summary of the variation of
aquifer potential with bedrock resis-tivity.
Final Groundwater Potential Map of
the Study Area
Final groundwater potential map of the
study area was produced in order to
draw the final conclusion from the eval-uated
maps. The weights that have been
assigned in Table 1 – Table 7 were used
to get the weights of Overburden Thick-
Figure 9. Bedrock relief map.
Table 7. Aquifer potential as a function of bedrock resistivity.
Bedrock Resistivity (Ω m)
Range Aquifer Characteristics Weighting
<750 High fracture permeability as a result of weathering; high
aquifer potential 10
750–1500 Reduced influence of weathering; medium aquifer potential 7.5
1500–3000 Low aquifer potential 5
>3000 Little or no weathering of the bedrock; negligible potential 2.5
23. The groundwater potential evaluation at industrial estate Ogbomoso, ... 385
ness, Anisotropy Coefficient, Weath-ered
Layer Resistivity, Transverse Re-sistance
and Bedrock Resistivity of the
study area.
A single weighted average is then deter-mined
from the geometric mean of the
five weights to produce the 2-Dimen-sional
RMZ-M&G 2012, 59
groundwater potential map of the
investigated area (figure 10). The map
presents local groundwater prospects of
the study area which is zoned in to high,
medium and low groundwater potentials.
Area with colour brown on the map con-stitute
the low groundwater potential
zone (i. e. VES 1, VES 3, VES 4, VES 5,
VES 7 and VES 10) while area with col-our
blue constitute the high groundwa-ter
potential zone (i. e. VES 2 and VES
6). Medium groundwater potential zone
share its colour between brown and blue,
this is noted at the Northeastern side of
the study area (I .e. VES 8 and VES 9).
The Southern (VES 6) and the Eastern
(VES 2) part of the study area are seen
to have relatively higher groundwater
potential than the Northeastern (VES
8 and VES 9) region of the study area.
Southwestern, Southeastern, Western,
Northern and Northwestern (i. e. VES 1,
VES 3, VES 4, VES 5, VES 7 and VES
10) regions are seen to have low ground-water
potential in the study area. These
zones with low groundwater potential
will be good for engineering purposes
(i.e. construction of factories).
Figure 10. Final groundwater potential map of the study area
24. 386 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
Conclusion
Though the study area was assigned
as an industrial estate, as long as wa-ter
still remains one of our essential
amenities in life, the groundwater po-tential
evaluation in the industrial es-tate
Ogbomoso cannot be overlooked.
Ignorantly without carrying out geo-physical
survey, the building contrac-tor
might have decided to build on the
promising areas for groundwater ex-ploration
which will lead to scarcity
of groundwater in the study area. Also,
building of factories on promising are-as
for groundwater exploration is even
disastrous to the users in the future.
The study has been able to highlight
the importance of resistivity method in
effective hydrogeologic characteriza-tion
and groundwater exploration. This
study has proved to be quite successful
for mapping outrock types, structural
formations and fractures which would
not have been observed at the surface.
The presence of weathered layer and
fractured basement are key compo-nents
of aquifer system and zone of
groundwater accumulation in industrial
estate, Ogbomoso. A multidimensional
approach to this study (that is mod-eled
curves and the maps presented for
groundwater potential evaluation) has
made the study both very qualitative
and quantitative as information missed
by any of the methods is revealed by
the other and thereby necessitating jus-tifiable
conclusions.
It can be concluded that the low resis-tivity
and significantly thick weathered
rock/clay and the fractured basement
constitute the aquifer in this area. Re-sults
from this study have revealed that
the Southern and Eastern parts of the
study area are the most promising re-gion
for borehole development. How-ever,
Northeastern region of the study
area can also be considered as fair for
borehole development as it has been
shown from Figure 10.
It is recommended that detailed work
be done in this industrial estate using
other relevant geophysical methods so
as to confirm the fractures predicted
and to elucidate the patterns of the
fractures.
Acknowledgements
The corresponding author is grateful to
Mr. E. O. and Mrs. C. J. Adagunodo,
Miss T. O. Ayinla, Prof. Bayo Ajulo,
and Mrs V. A. Ajulo (nee Adagunodo)
for the financial support in the course
of carrying out this research.
References
Acworth, R. I. (1987): The development
of crystalline basement aquifers in a
tropical environment. Quarterly Jour-
25. The groundwater potential evaluation at industrial estate Ogbomoso, ... 387
nal of Engineering Geology, Vol. 20,
265–272.
Aderinto, I. O. (1986): Estimating aquifer
transmissivity in the Basement Com-plex
using Dar-Zarrouk parameters,
Unpublished M. Sc Thesis, University
of Ibadan, Nigeria.
Ajibade, A. C., Rahama n, M. A. & Ogezi,
A. E. O. (1988): The Precambrian of
Nigeria, a Geochronological Survey.
Publication of the Geological Survey
of Nigeria.
Alagbe, O. A. (2005): Integration of
Electrical Resistivity Techniques and
Lineament analysis in Hydrogeologi-cal
investigation of parts of Ogbomo-so,
South – Western Nigeria. M.Tech
Thesis, Ladoke Akintola University of
Technology, Ogbomoso, Nigeria.
Ass eez, L. O. (1972): Hydrogeology of
Southwestern Nigeria. The Nigerian
Engineer, Vol. 7, (1), 22–44.
Ayantunji, B. G. (2005). Integrated use of
electrical and electromagnetic (VLF)
method in the delineation of the
fault pattern of Odokoto, Ogbomoso,
Southwestern Nigeria. M.Tech The-sis,
Department of Pure and Applied
Physics, Ladoke Akintola University
of Technology, Ogbomoso, Nigeria.
Bala, A. N. & Ike, E. C. (2001): The aq-uifer
of the crystalline basement rocks
of Gusau area, Northwestern Nigeria.
Journal of Mining and Geology, Vol.
2, (37), 177–184.
Benson, S. & Jones, C. R. C. (1988): The
combined EMT geophysical method
for sitting boreholes. Groundwater,
Vol. 26, 45–63.
Bia nchi, L. & Snow, D. T. (1969): Per-meability
of crystalline rocks from
RMZ-M&G 2012, 59
measured orientations and apertures
of fractures. Annals of Arid zones, Vol.
8, (2), 231–245.
Braga, A. C. O., Filho, W. M. & Dour-ado,
J. C. (2006): Resistivity (DC)
method applied to aquifer protection
studies. Revista Brasileira Geofysica,
Vol. 24, 573–581.
Carruthers, R. M. & Smit h, I. F. (1992):
The use of ground electrical survey
methods for siting water supply bore-holes
in shallow crystalline basement
terrains. In: WRIGHT, E. P. & BUR-GESS,
W. G. (eds). The hydrogeology
of crystalline basement aquifers in Af-rica.
Geological society special publi-cation,
No. 66, pp. 203–220.
Dan-Hassa n, M. A. & Olorunfemi , M. O.
(1999): Hydrogeophysical investiga-tion
of a basement terrain in the north
central part of Kaduna State, Nigeria.
Journal of Mining and Geology, Vol.
2, (35), 189–206.
Davis , S. N. & De Wiest , R. J. M. (1966):
Hydrogeology. Wiley, New York.
Duffin, W. J. (1979): Electricity and Mag-netism.
3rd Ed. The English Book Soci-ety,
58–61, 155–156.
Eduvie, M. O. & Olabode, O. T. (2001):
Evaluation of aquifer potential in the
crystalline basement using geoelec-tric
sounding data from the southern
part of Kaduna State, Nigeria. Water
Resources-Journal of NAH, Vol. 12,
(2), 56–61.
Esu, O. E. (1993): Fracture Mapping-
Scientific basis for well siting in hard
rocks. Water Resources-Journal of Ni-gerian
Association of Hydogeologists
(NAH), Vol. 4, (1&2), 25–35.
Evwaraye, A. O. & Mgbanu, E. N. (1993):
26. 388 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
Electromagnetism and Modern Phys-ics
for physical sciences. Spectrum
books Ltd, 86–88.
Fitt erma n, D. V. & Stewart, M. T. (1986):
Transient electromagnetic sounding
for groundwater. Geophysics, Vol. 51,
995–1005.
Grant, F. S. & West , G. F. (1965): Inter-pretation
theory in applied geophys-ics.
McGraw Hill Book Company,
385–443.
Hadi, T. N. (2009): Geoelectric Investiga-tion
of the Aquifer Characteristics and
Groundwater Potential in Behbahan
Azad University Farm, Khuzestan,
Iran. Journal of Applied Sciences, Vol.
9(20), 3691–3698.
Henriet, J. P. (1975): Direct applications
of the Dar-Zarrouk parameters in
groundwater surveys. Geophys. Pros-pect.,
Vol. 24, 344–353.
Keller, S. & Fris chnecht, N. (1970): An
interactive computer/graphic – dis-play-
terminal system for interpreta-tion
of resistivity soundings. Geophys-ics
prospect, Vol. 23, 449–458.
Lenkey, L., Ham ori, Z. & Mihalffy, P.
(2005): Investigating the hydrogeolo-gy
of a water-supply area using direct-current
vertical electrical soundings.
Geophysics, Vol. 70(4), H1–H19.
MacDonald, A. M. & Davies, J. (2000): A
brief review of groundwater for rural
water supply in Sub-Saharan Africa.
B.G.S. Technical Report. W.C./00/33.
Mai llet, R. (1974): The fundamental
equations of electrical prospecting.
Geophysics, Vol. 12: 529–556.
Mazac, O., Kelly, W. E. & Landa, I.
(1987): Surface geoelectrical methods
for groundwater pollution and protec-tion
studies. Journal of Hydrology,
Vol. 93, 277–287.
McNeill, J. D. (1987): Advances in elec-tromagnetic
methods for groundwater
studies. Proceedings of Exploration
’87–Applications of Geophysics and
Geochemistry, 678–702.
Meju, M. A., Fontes, S. L., Oliveira, M.
F. B., Lima , J. P. R., Ulugerger, E. U.
& Carras quilla, A. A. (1999): Re-gional
aquifer mapping using com-bined
VES-TEM-AMT?EMAP meth-ods
in the semiarid eastern margin of
Parnaiba Basin, Brazil. Geophysics,
Vol. 64(2), 337–356.
Niwas , S. & Singhal, D. C. (1981): Esti-mation
of aquifer transmissivity from
Dar-Zarrouk parameters in porous me-dia.
J. Hydrol. Vol. 50, 393–399.
Odusa nya, B. O. (1989): An empirical re-sistivity
model for predicting shallow
groundwater occurence in the Base-ment
Complex. M.Sc. thesis, Univer-sity
of Ibadan, Nigeria.
Okhue, E. T. & Olorunfemi , M. O. (1991):
Electrical resistivity investigation of a
typical Basement Complex area. The
Obafemi Awolowo University campus
case study. J. Mining Geol., Vol. 2,
(27), 63–69.
Olas ehinde, P. I. (1989): Elucidating frac-ture
patterns of the Nigerian Basement
Complex using electrical resistiv-ity
method. Z. Angew. Geowiss. Heff.,
Vol. 8, (5), 109–120.
Olayinka , A.I., Akpa n, E. J. & Magbagbe-ola,
O. A. (1997): Geoelectric sound-ing
for estimating aquifer potential in
the crystalline basement area around
shaki, southwestern Nigeria. Water
Resources- Journal of NAH, Vol. 8, (1
27. The groundwater potential evaluation at industrial estate Ogbomoso, ... 389
& 2), 71–81.
Olorunfemi , M. O. & Fas uyi, S. A.
(1993): Aquifer types and the geoelec-trical/
hydrogeologic characteristics of
part of the central basement terrain of
Nigeria. Journal of African earth sci-ences,
Vol. 16, 309–317.
Olorunfemi , M. O., Ojo, J. O. & Aki n-tunde,
O. M. (1999): Hydrogeophysi-cal
evaluation of the groundwater
potential of Akure metropolis, South-western
Nigeria. J. Mining Geol., Vol.
2 (35), 207–228.
Olorunfemi , M. O. & Okhue, E. T. (1992):
Hydrogeologic and Geologic Signifi-cance
of a Geoelectric Survey at Ile-
Ife, Nigeria Journal of Mining and
Geology, Vol. 28, (2), 221–229.
Olorunfemi , M. O., Olanrewaju, V. O.
& Alade, O. (1991): On the electri-cal
anisotropy and groundwater yield
in a Basement Complex area of South
Western Nigeria. Journal of African
Earth Sciences, Vol. 12, No. 3, pp.
467–472.
Olorunfemi , M. O. & Olorunniwo, M. A.
(1985): Geoelectric parameters and
aquifer characteristics of some parts
of southwestern Nigeria. Geologia
Applicata E, Idrogeologia, XX, part 1,
pp. 99–109.
Oluyide, P. O. & Udey, A. N. (1965): Pre-liminary
comments on the fracture
system of Nigeria. Paper presented at
the national seminar on earthquakes
in Nigeria, A.B.U., Zaria, Nigeria.
Omorinbola, E. (1979): A quantitative
evaluation of groundwater storage in
Basement Complex regoliths in south-eastern
Nigeria. Ph.D Thesis, Univer-sity
of Ibadan, 254.
RMZ-M&G 2012, 59
Omosuyi, G. O. & Enika nselu, P. A.
(1999): Direct Current Resistivity
Sounding for Groundwater Potential
in Basement Complex of North-Cen-tral
Nigeria. J. Sci. Eng. Tech., Vol. 1,
(2), 331–334.
Omosuyi, G. O. (2010): Geoelectric assess-ment
of groundwater prospect and vul-nerability
of overburden aquifers at Idan-re,
South Western Nigeria. Ozean Jour-nal
of Applied Sciences, Vol. 3(1), 19–28.
Onu, N. N. (2003): Estimates of the rela-tive
specific yield of aquifers from
geo-electrical sounding data of the
coastal plains of Southwestern Nige-ria.
J. Technology. Educ. Nig., Vol. 8,
69–83.
Onuoha, K. M. & Mbazi, F. C. C. (1988):
Aquifer transmissivity from electrical
sounding data: the case of Ajali sand-stone
aquifers, Southeast of Enugu,
Nigeria. In: C. O. Ofoegbu (editor),
Groundwater and Mineral resources
of Nigeria, Friedr. Vieweg & Son Pub-lishers,
pp. 17–30.
Patra, H. P. & Nath, S. K. (1999):
Schlumberger Geoelectric Sounding
in Groundwater (Principle, Interpreta-tion
and Application). Published by A.
A. Balkema/Rotterdam/Brookfield.
Rahama n, M. A. (1976): Review of the
Basement Geology of Southwestern
Nigeria. In: Kogbe, C. A. (ed.) Geol-ogy
of Nigeria. Elizabethan Pub. Co.,
Lagos. 41–58.
Russ , W. (1957): The Geology of part
of Niger, Zaria and Sokoto Province
.Bull. Geological Surv Nigeria, Vol.
27, pp. 42.
Surfer 8, (2002). Version 8.01. Surface
mapping system. Golden Software
28. 390 Sunmonu, L. A., Adagunodo, T. A., Olafis oye, E. R., Oladejo, O. P.
RMZ-M&G 2012, 59
Inc, Colorado.
Todd, D. K. (1980): Groundwater Hydrol-ogy.
2nd Edn., John Willey Sons Inc.,
New York, pp. 539.
Toto, E. A., Kerrouri, C., Zouhri, I., El
Bas ri, M., Ibenbrahim , A., Turner, D.
C. (1983): Upper Proterozoic Schist
Belts in the Nigerian Sector of the
Pan-African Province of West Africa.
Precamb. Res. 21, 55–79.
Truss well, J. F. & Cope, R. N. (1963): The
Geology of Part of Nigeria and Zaria
province. Northern Nigeria Bull. Geo-logical
Surv Nigeria, Vol. 29, pp. 42.
Vander Velpen, B. P. A. (2004): WinRE-SIST
Version 1.0. Resistivity Sound-ing
Interpretation Software. M.Sc. Re-search
Project, ITC, Delft Netherland.
Wright, E. P. (1990): Basement aquifers in
Africa. Commonwealth Science Tech-nical
Paper, Vol. 273, (2), 363–394.
Wright, E. P. (1992): The hydrogeology
of crystalline basement aquifers in Af-rica.
In: Wright, E. P. & Burgess, W.
G. (eds). The hydrogeology of crystal-line
basement aquifers in Africa. Geo-logical
society special publication No.
66, pp. 1–27.
Zohdy, A. A. R. (1973): The use of schlum-berger
and equatorial in groundwater
investigation near EL Paso, Texas.
Geophysics, Vol. 34 (5), 713–728.
Zohdy, A. A. & Maboy, D. R. (1974):
Application of surface geophysics to
groundwater investigation. U.S. Geol.
Surv. Book 2 Ch D1, 304–320.