The document summarizes an engineering geophysical investigation conducted around Ungwan Doka, Shika area in northwestern Nigeria. Vertical electrical soundings using Schlumberger configuration were performed at 18 locations. The resistivity data revealed 2-4 subsurface layers: a topsoil layer, a weathered basement layer, a partly weathered/fractured basement layer, and a fresh basement layer. Resistivity values and layer thicknesses varied across layers and locations. The study characterized the subsurface and evaluated its competence, structural variations, groundwater potential, and safety of the hydrogeologic system to inform engineering design.
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
Geotechnical Investigation for Design and Construction of Civil Infrastructur...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.
Engineering geologists provide geological and geotechnical recommendations, analysis, and design associated with human development and various types of structures. Engineering geology is a promising subject for operational applications of geological knowledge. The future lies in this subject. Opportunities will increase for students specializing in this subject.
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
Geotechnical Investigation for Design and Construction of Civil Infrastructur...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.
Engineering geologists provide geological and geotechnical recommendations, analysis, and design associated with human development and various types of structures. Engineering geology is a promising subject for operational applications of geological knowledge. The future lies in this subject. Opportunities will increase for students specializing in this subject.
A study was conducted at a sawah site in Ghana to examine the relationship between landscape
position and some selected soil properties with the aim of generating adequate data for modeling
landscape relationships and to aid both researchers and farmers in taking critical management
decisions. Soil properties namely total porosity, moisture content, infiltration rates, hydraulic
conductivity, sand content, silt content, clay content, gravel concentration, bulk density, soil pH, total
nitrogen, soil organic matter and cation exchange capacity were collected and analysed. Data were
collected at the foot slopes, middle slopes and at the upper slopes from four major landuses (maize, oil
palm, natural vegetation and plantain) in the study area. Simple statistical parameters such as mean
and standard deviation were used to analyse the data. Moisture content, total porosity, soil pH, organic
matter and carbon and total nitrogen increased downslope whilst sand content, clay content, bulk
density occurred at upper slopes decreased downslope. Management practices appeared to have
influenced infiltration rate, hydraulic conductivity and silt content.
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.
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.
Geology is the scientific study of the all constituents of planets, their internal and external forms and processes. More precisely, it is the study of nature, structure and history of the planet. Earth is the home to all life, well known to the humankind. Geology, itself, is a major part of The Earth and atmospheric sciences, which were born as twins . The subject of geology encompasses all aspects including the composition, structure, physical properties, and history of a planets'( like Earth's) inter-related components and the processes that are shaping the features on the surface. Geologists are the scientists who study the origin, occurrence, distribution and utilities of all materials(metallic, non-metallic, inorganic, etc), minerals, rocks, sediments, soils, water, oil and all other inorganic natural resources. It is a very vast subject covering a wide spectrum of scientific principles and holding hundred and fifty plus scientific branches. This report enumerates and highlights most of them, in a nutshell, for all those who intends to know for planning their career path.
Sedimentology and Paleoenvironment of Deposition of the Deba-Fulani Member of...AZOJETE UNIMAID
The sedimentology and paleoenvironment of the Deba-Fulani Member of the Pindiga Formation were investigated on the basis of their grain size distribution. Granulometric analysis has indicated that the samples are generally well to moderately sorted with skewness values ranging from negatively to positively skewed which may indicate influence of both marine and fluvial conditions. Bivariate plot relationships of standard deviation vs. mean, standard deviation vs. skewness, first percentile vs. mean also indicated both fluvial and marine setting for the middle part of the Pindiga Formation member. However, most of the bivariate plot showed dominance of fluvial environment. The probability curve plot shows a prevalence of three-sand population curves which are usually associated with wave processes indicating marine conditions for most part of the Deba-Fulani Member.
This is a presentation onEngineering Geology.
It contains-
>>Meaning
>>Definition
>>Objective
>>Scope in Construction;Water Resource Developement;Town and Regional Planning.
>>Age Of Earth.
---------------------------------------------------------------------------------------------------------------------------
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.
Integrated ERT and Magnetic Surveys in a Mineralization Zone in Erkowit - Red...IJERA Editor
The present study focus on integrated geophysical surveys carried out in the mineralization zone in Erkowit region, Eastern Sudan to determine the extensions of the potential ore deposits on the topographically high hilly area and under the cover of alluvium along the nearby wadi and to locate other occurrences if any. The magnetic method (MAG) and the electrical resistivity tomography (ERT) were employed for the survey. Eleven traverses were aligned approximately at right angles to the general strike of the rock formations. The disseminated sulfides are located on the alteration shear zone which is composed of granitic and dioritic highly ferruginated rock occupying the southwestern and central parts of the area, this was confirmed using thin and polished sections mineralogical analysis. The magnetic data indicates low magnetic values for wadi sedimentary deposits in its southern part of the area, and high anomalies which are suspected as gossans due to magnetite formed during wall rock alteration consequent to mineralization. The significant ERT imagesdefinelow resistivity zone as traced as sheared zones which may associated with the main loci of ore deposition. The study designates that correlation of magnetic and ERT anomalies with lithology are extremely useful in mineral exploration due to variations in some specific physical properties of rocks.
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.
A study was conducted at a sawah site in Ghana to examine the relationship between landscape
position and some selected soil properties with the aim of generating adequate data for modeling
landscape relationships and to aid both researchers and farmers in taking critical management
decisions. Soil properties namely total porosity, moisture content, infiltration rates, hydraulic
conductivity, sand content, silt content, clay content, gravel concentration, bulk density, soil pH, total
nitrogen, soil organic matter and cation exchange capacity were collected and analysed. Data were
collected at the foot slopes, middle slopes and at the upper slopes from four major landuses (maize, oil
palm, natural vegetation and plantain) in the study area. Simple statistical parameters such as mean
and standard deviation were used to analyse the data. Moisture content, total porosity, soil pH, organic
matter and carbon and total nitrogen increased downslope whilst sand content, clay content, bulk
density occurred at upper slopes decreased downslope. Management practices appeared to have
influenced infiltration rate, hydraulic conductivity and silt content.
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.
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.
Geology is the scientific study of the all constituents of planets, their internal and external forms and processes. More precisely, it is the study of nature, structure and history of the planet. Earth is the home to all life, well known to the humankind. Geology, itself, is a major part of The Earth and atmospheric sciences, which were born as twins . The subject of geology encompasses all aspects including the composition, structure, physical properties, and history of a planets'( like Earth's) inter-related components and the processes that are shaping the features on the surface. Geologists are the scientists who study the origin, occurrence, distribution and utilities of all materials(metallic, non-metallic, inorganic, etc), minerals, rocks, sediments, soils, water, oil and all other inorganic natural resources. It is a very vast subject covering a wide spectrum of scientific principles and holding hundred and fifty plus scientific branches. This report enumerates and highlights most of them, in a nutshell, for all those who intends to know for planning their career path.
Sedimentology and Paleoenvironment of Deposition of the Deba-Fulani Member of...AZOJETE UNIMAID
The sedimentology and paleoenvironment of the Deba-Fulani Member of the Pindiga Formation were investigated on the basis of their grain size distribution. Granulometric analysis has indicated that the samples are generally well to moderately sorted with skewness values ranging from negatively to positively skewed which may indicate influence of both marine and fluvial conditions. Bivariate plot relationships of standard deviation vs. mean, standard deviation vs. skewness, first percentile vs. mean also indicated both fluvial and marine setting for the middle part of the Pindiga Formation member. However, most of the bivariate plot showed dominance of fluvial environment. The probability curve plot shows a prevalence of three-sand population curves which are usually associated with wave processes indicating marine conditions for most part of the Deba-Fulani Member.
This is a presentation onEngineering Geology.
It contains-
>>Meaning
>>Definition
>>Objective
>>Scope in Construction;Water Resource Developement;Town and Regional Planning.
>>Age Of Earth.
---------------------------------------------------------------------------------------------------------------------------
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.
Integrated ERT and Magnetic Surveys in a Mineralization Zone in Erkowit - Red...IJERA Editor
The present study focus on integrated geophysical surveys carried out in the mineralization zone in Erkowit region, Eastern Sudan to determine the extensions of the potential ore deposits on the topographically high hilly area and under the cover of alluvium along the nearby wadi and to locate other occurrences if any. The magnetic method (MAG) and the electrical resistivity tomography (ERT) were employed for the survey. Eleven traverses were aligned approximately at right angles to the general strike of the rock formations. The disseminated sulfides are located on the alteration shear zone which is composed of granitic and dioritic highly ferruginated rock occupying the southwestern and central parts of the area, this was confirmed using thin and polished sections mineralogical analysis. The magnetic data indicates low magnetic values for wadi sedimentary deposits in its southern part of the area, and high anomalies which are suspected as gossans due to magnetite formed during wall rock alteration consequent to mineralization. The significant ERT imagesdefinelow resistivity zone as traced as sheared zones which may associated with the main loci of ore deposition. The study designates that correlation of magnetic and ERT anomalies with lithology are extremely useful in mineral exploration due to variations in some specific physical properties of rocks.
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.
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.
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.
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.
Landslide Investigation of Ikwette, Obudu Local Government Area of Cross Rive...iosrjce
This study investigates the causes of a slope failure at Ikwette, Obudu local Government Area of
Cross River State, Nigeria in 2013. It also involves a slope stability analysis of the failed slope, which was OB1.
To understand instability in the study area, a combination of field, geotechnical and statistical analysis were
undertaken. Some obtained parameters were then applied in a slope/W Geostudio 2012 software program which
uses the conventional limit equilibrium methods to simulate the dominant factors inducing instability. Results of
the geotechnical investigations of the samples taken from Ikwette, showed an average maximum dry density
value of 1.63kg/m3
, which was a low to moderate value and average optimum moisture content value of 18%.
Analysis from the particle size distribution, showed that the particle sizes where silty sand, with a Coefficient of
uniformity (Cu) value of 1.8 and Coefficient of curvature (Cc) value of 0.968, indicating that the soil is
uniformly or poorly graded. Triaxial compression test showed an angle of internal friction and cohesion values
averaging around 12.65° and 43kPa respectively, which indicates that the shear strength of the soil was
reduced, due to the activities of high precipitation intensity which increased to a monthly value of 375.3mm
before the landslide event. Also, the factor of safety value for the slope in OB1, where the landslide occurred
was 1.114, which is close to the value for an incipient failure. Hence the results of the aforementioned methods
and simulation shown can be used in predicting areas of possible landslides, as well as the causes of such soil
deformations, and as such, safety measures could be taken against the reoccurrence of landslides in such areas.
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.
Evidence of Geological Control on Reservoir Petrophysical Properties of “Beta...Premier Publishers
Geological controls on the reservoir petrophysical properties of “BETA Field” have been carried out using suites of wireline logs. Stratigraphic relationship among the reservoir sand bodies including their geometrical architectures, and their stacking patterns were also established. Exponential regression analysis of some of the petrophysical parameters were carried out to establish any relationship with depositional processes as well as depositional environments of the reservoir sand bodies in the field. The main factor controlling petrophysical properties and thickness for these reservoirs is the type of sandstone facies. The petrophysical evaluation of both reservoirs (K and Q) depicts porosity range from fair to very good across wells (i.e 11% to 25%). From the evaluated reservoirs porosity, there is no significant reduction of porosity with depth increase. The values obtained for the permeability of both reservoirs (K and Q) varied widely and inconsistent across the wells in the study field. The various depositional environments established in BETA field include fluvial, tidal channel, mouth bars, delta front, and the reservoir sands occurring in different depositional settings, resulting from different depositional processes, which had a wide range of petrophysical properties.
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.
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.
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.
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.
Groundwater prospecting and Aquifer Delineation using Vertical Electrical Sou...iosrjce
A total of twenty seven (27) vertical electrical soundings (VES) where carried out on the basement
complex area of Kumbotso Local Government Area of Kano with a spread of 40m-45m adopted. The results
obtained revealed three to four geo-electric layers of the subsurface. The third weathered basement and a forth
fractured basement rock constitutes the Aquiferous water bearing layers with resistivity ranges from 6Ωm -
265Ωm respectively with average thickness of 19m and 15m respectively. The result shows the weathered
regolith to be thicker than the fractured bedrock layer; average depth range of boreholes in the area is between
30m-35m while the average static water levels in dug wells is 8.3m. It is highly recommended that a spread of
between 75-85m be used in the future and also the use of EM method to locate deep fractures as important in
maximizing the borehole yield.
Similar to Engineering geophysical investigation around ungwan doka, shika area within the basement complex of north western nigeria. (20)
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
GraphSummit Singapore | The Art of the Possible with Graph - Q2 2024Neo4j
Neha Bajwa, Vice President of Product Marketing, Neo4j
Join us as we explore breakthrough innovations enabled by interconnected data and AI. Discover firsthand how organizations use relationships in data to uncover contextual insights and solve our most pressing challenges – from optimizing supply chains, detecting fraud, and improving customer experiences to accelerating drug discoveries.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
Enchancing adoption of Open Source Libraries. A case study on Albumentations.AIVladimir Iglovikov, Ph.D.
Presented by Vladimir Iglovikov:
- https://www.linkedin.com/in/iglovikov/
- https://x.com/viglovikov
- https://www.instagram.com/ternaus/
This presentation delves into the journey of Albumentations.ai, a highly successful open-source library for data augmentation.
Created out of a necessity for superior performance in Kaggle competitions, Albumentations has grown to become a widely used tool among data scientists and machine learning practitioners.
This case study covers various aspects, including:
People: The contributors and community that have supported Albumentations.
Metrics: The success indicators such as downloads, daily active users, GitHub stars, and financial contributions.
Challenges: The hurdles in monetizing open-source projects and measuring user engagement.
Development Practices: Best practices for creating, maintaining, and scaling open-source libraries, including code hygiene, CI/CD, and fast iteration.
Community Building: Strategies for making adoption easy, iterating quickly, and fostering a vibrant, engaged community.
Marketing: Both online and offline marketing tactics, focusing on real, impactful interactions and collaborations.
Mental Health: Maintaining balance and not feeling pressured by user demands.
Key insights include the importance of automation, making the adoption process seamless, and leveraging offline interactions for marketing. The presentation also emphasizes the need for continuous small improvements and building a friendly, inclusive community that contributes to the project's growth.
Vladimir Iglovikov brings his extensive experience as a Kaggle Grandmaster, ex-Staff ML Engineer at Lyft, sharing valuable lessons and practical advice for anyone looking to enhance the adoption of their open-source projects.
Explore more about Albumentations and join the community at:
GitHub: https://github.com/albumentations-team/albumentations
Website: https://albumentations.ai/
LinkedIn: https://www.linkedin.com/company/100504475
Twitter: https://x.com/albumentations
zkStudyClub - Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex ProofsAlex Pruden
This paper presents Reef, a system for generating publicly verifiable succinct non-interactive zero-knowledge proofs that a committed document matches or does not match a regular expression. We describe applications such as proving the strength of passwords, the provenance of email despite redactions, the validity of oblivious DNS queries, and the existence of mutations in DNA. Reef supports the Perl Compatible Regular Expression syntax, including wildcards, alternation, ranges, capture groups, Kleene star, negations, and lookarounds. Reef introduces a new type of automata, Skipping Alternating Finite Automata (SAFA), that skips irrelevant parts of a document when producing proofs without undermining soundness, and instantiates SAFA with a lookup argument. Our experimental evaluation confirms that Reef can generate proofs for documents with 32M characters; the proofs are small and cheap to verify (under a second).
Paper: https://eprint.iacr.org/2023/1886
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
UiPath Test Automation using UiPath Test Suite series, part 5DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 5. In this session, we will cover CI/CD with devops.
Topics covered:
CI/CD with in UiPath
End-to-end overview of CI/CD pipeline with Azure devops
Speaker:
Lyndsey Byblow, Test Suite Sales Engineer @ UiPath, Inc.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Generative AI Deep Dive: Advancing from Proof of Concept to ProductionAggregage
Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
Pushing the limits of ePRTC: 100ns holdover for 100 days
Engineering geophysical investigation around ungwan doka, shika area within the basement complex of north western nigeria.
1. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
Engineering Geophysical Investigation Around Ungwan Doka,
Shika Area within the Basement Complex of North-Western
Nigeria
⃰ FADELE S.I (M.Sc), JATAU B.S (Ph.D) AND UMBUGADU A. (M.Sc)
Nasarawa State University, Keffi, Nigeria
⃰ Email: fadeleidowu@yahoo.com +2348066035524; bsjatau@yahoo.co.uk +2348034529326
Abstract
Geophysical investigation for engineering or environmental studies was carried out around Ungwan Doka of
Shika area which falls within the Basement Complex of North-Western Nigeria. The study is aimed at evaluating
the competence of the near surface formation as foundation materials, and to unravel the subsurface profile
which in turn determines if there would be any subsurface lithological variation(s) that might lead to structural
failure at the site and evaluating the groundwater potential of the site and determining the level of safety of the
hydrogeologic system. Vertical Electrical Sounding (VES), using Schlumberger configuration was adopted. A
total of 18 VES was conducted. The data obtained were subjected to 1-D inversion algorithm to determine the
layer parameters. The geoelectric section revealed two to four lithologic units defined by the topsoil, which
comprises clayey-sandy and sandy lateritic hard pan; the weathered basement; partly weathered/fractured
basement and the fresh basement. The resistivity values range from 26 m - 373 m; 77 m - 391 m; 473 m -
708 m; and 1161 m - 3600 m in the topsoil, weathered, fractured basement and fresh basement respectively.
Layer thicknesses vary from 0.38m – 6.58m in the topsoil, 1.1m – 33.04m in the weathered layer, 5.86m – 34.1m
in the fractured basement. Depth from the surface to bedrock/fresh basement generally varied between 2.65m
and 37.75m. Based on the resistivity values, it is concluded that the subsurface material up to the depth of 25m is
competent and has high load-bearing capacity. However, resistivity values less than 100 m at depths of
10m-15m indicate high porosity, high clayey sand content and high degree of saturation which are indications of
soil conditions requiring serious consideration in the design of massive engineering structures. The
hydrogeologic system at the site is vulnerable to contamination. Hence, the result reasonably provide a basis for
which groundwater potential zones are appraised for safety in case potential sources of groundwater
contamination sites such as septic tanks and sewage channels are planned for the area under study.
Key words: VES, Top soil, Weathered Basement, Partly weathered or Fractured Basement, Fresh ,Basement
1. Introduction
The failure statistic of structures such as buildings, tarred roads and bridges throughout the nation is increasing
geometrically. Most of these failures were caused by swelling clays (Blyth and Freitas, 1988). In recent times,
the collapse of civil engineering structures has been on the increase for reasons associated with subsurface
geological sequence (Omoyoloye et al., 2008). The foundation of any structure is meant to transfer the load of
the structure to the ground without causing the ground to respond to uneven and excessive movement. In order to
achieve this, most buildings are supported on pads, strips and rafts or piles (Blyth and Freitas, 1988). Therefore
the knowledge of the probable cause of rampant failure of building foundations due to subsurface movements
giving rise to cracks or structural differential settlements has been a great concern to geoscientists. This has
helped to distinguish between a continuing movement, which is often more likely to be a problem and those of
single events, which may not require repair depending on the extent of damage. However, adequate insight on
the types and patterns of foundation-based cracks and their evaluation has necessitated the need to consider the
geological and geophysical basis for buildings’ failure and adequate precaution taken to minimize such disaster.
The amount, type and direction of foundation movement are commonly noted from the bulging of brick or
masonry blocks. These in turn reveal the risk of vertical collapse or horizontal dislocation. The risk could be
traced to the height of construction, materials used for the building, site factor, earth loading or water. Other
factors include the seismic action, atmospheric disaster and accident (Omoyoloye et al., 2008). If cracks are old
with no sign of continuing or recurrent movement, building inspectors accept monitoring rather than quickly
recommending repairs. Most house settling cracks are basically caused by either the differences in expansion and
compression coefficients of the construction materials, relative changes in the shapes and sizes of saturated soils
or the dynamic earth. The need for subsurface geophysical investigation has therefore become very imperative so
as to prevent loss of valuable properties and lives that always accompany such a failure. Foundation evaluation
of a new site is necessary so as to provide subsurface and aerial information that normally assist civil engineers,
builders and town planners in the design and siting of foundations of civil engineering structures (Omoyoloye, et
al., 2008). Geophysical methods such as the Electrical Resistivity (ER), Seismic refraction, Electromagnetic
17
2. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
(EM), Magnetic and Ground Penetrating Radar (GPR) are used singly or in combinations for engineering site
investigations. The applications of such geophysical investigation are used for the determination of depth to
bedrock, structural mapping and evaluation of subsoil competence (Burland and Burbidge, 1981; Burger, 1992).
The engineering geophysical investigation was carried out at Ungwan Doka in Shika area, Kaduna State,
North-Western Nigeria, aimed at determining the depth to the competent stratum in the subsurface, delineation
of areas that are prone to subsidence or some form of instability, evaluating the groundwater potential of the site
and determining the level of safety of the hydrogeologic system in the study area.
2. Location and Topography of the Study area
The study area lies between Latitudes 110 10’ 49”N - 110 11’ 05” N and Longitudes 70 35’40”E - 70 38’ 50” E.
The site is situated along the Sokoto road, North West of Zaria (Fig. 1). The topography is that of high plain (flat
terrain) of Hausa land. The site is located within the tropical climatic belt with Sudan Savannah vegetation. The
environment is Savannah type with distinct wet and dry season. The rainfall regime is simple but with slight
variation which consists of wet season lasting from May to September and characterized by heavy down pour at
the start and end of the rainy season. The annual rainfall varies between 800 mm to 1090 mm while the mean
annual temperature ranges between 240C to 310C reaching a maximum of about 360C around April (Hore,1970;
Goh and Adeleke, 1978).
3. Geology of Study Area
The study area is laid on undifferentiated Basement Complex. Though there were no rock out-crops within the
site, observation however revealed that the weathered bedrock in some existing hand-dug wells within the site
and environs indicates the occurrence of granitic rocks within the site which are porphiritic in texture. The study
area falls within the Metasediments of the Basement Complex (McCurry, 1970). The Basement Complex in
Kaduna state was affected by an Orogeny, which predated the emplacement of the Older Granite. During this
event, deformation of the basement produced north-south trending basins of Metasediment in the form of
Synclinoria. Tertiary earth movements tilted the Metasediments to north and warped the basement along the axis
of the uplift pass through the present Kaduna state having northwest trend. They have a pronounced effect on the
drainage pattern of the state. Through the process of metamorphism, migmatization and granitization that
occurred within at least two tectono-metamorpic cycles, the rocks were largely transformed into migmatites and
granite gneiss, with some relics of the original gneisses McCurry (1976). The Basement Complex was later
intruded by series of intermediate and acid plutonic rocks during the Pan African Orogeny according to McCurry
(1976). Oyawoye (1970), showed that there is structural similarity between the study area and the rest of West
Africa. (MacLeod et al 1971), reported that newer basalts often overlie alluvial deposits. The Younger Granites
are high level discordant intrusions in the Basement Complex and occupy approximately 8% of the total surface
area of Nigeria according to Rahaman (1976).
4. Methodology
Vertical Electrical Soundings (VES) using Schlumberger array were carried out at eighteen (18) stations. A
regular direction of N-S azimuth was maintained in the orientation of the profiles. Overburden in the basement
area is not as thick as to warrant large current electrode spacing for deeper penetration (Oseji, et al., 2005;
Okolie, et al., 2005), therefore the largest Current electrode spacing AB used was 200m, that is, 1/2AB=100m.
The principal instrument used for this survey is the ABEM (Signal Averaging System, (SAS 300) Terrameter.
The resistance readings at every VES point were automatically displayed on the digital readout screen and then
written down on paper.
5. Results and Discussion
Shlumberger array shown in figure 2 was adopted for the survey. A and B are point current electrodes through
which current is driven into the ground, while M and N are two potential electrodes to record the potential
distribution in the subsurface within the two current electrodes.
From Ohm’s law, the current I and potential V in a metal conductor at constant temperature are related as
follows:
V = IR (1)
Where R is the constant of proportionality termed resistance and it is measured in ohms. The resistance R, of a
conductor is related to its length L and cross sectional area A by;
R = ρL / A (2)
18
3. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
Where ρ is the resistivity and it is a property of the material considered.
From equation (1) and (2),
V = IρL / A (3)
The vertical electrical sounding (VES) with Schlumberger array involves fixing the potential electrodes at point
M and N, and symmetrically increasing the current electrode separation AB about the centre by displacing A and
B outwardly in steps. This will increase the depth of penetration within the separation AB. Thus the varying
resistivity measured when electrode array position is varied in an inhomogeneous medium is termed apparent
resistivity.
For simple treatment, a semi-infinite solid with uniform resistivity, ρ, is considered. A potential gradient is
measured at M and N when current electrodes located on the surface of the equipotential surface is semi-spheral
downward into the ground at each electrode. The surface area will then be 2πL2, where L is the radius of the
sphere. Thus
V = Iρ / 2πL (4)
By deduction then, the potential at M (VM), due to the two current electrodes, is
VM = Iρ/{2π (1/r1 – 1/r2)} (5)
Similarly, the potential at electrode N (VN) is given by
VN = Iρ/{2π (1/r3 – 1/r4)} (6)
where r1, r2, r3 and r4 are shown in Figure 2.
The potential difference, ∆V, acrss electrodes M and N is VM – VN. If the body is inhomogeneous like the study
area, apparent resistivity (ρa) is considered,
ρa = K (∆V/ I) (7)
Where ρa is apparent resistivity in ohm-metre, and
K = 2π [(1/r1 – 1/r2) - (1/r3 – 1/r4)] -1 (8)
K is called the geometric factor whose value depends on the type of electrode array used.
For Schlumberger array, if MN =2b and 1/2AB = L then,
K = π (L2/2b – b/2) (9)
The geometric factor, K, was first calculated for all the electrode spacings using the equation 9; K= π (L2/2b –
b/2), for Schlumberger array with MN=2b and 1/2AB=L. The values obtained, were then multiplied with the
resistance values to obtain the apparent resistivity, ρa, values (equation 7). Then the apparent resistivity, ρa,
values were plotted against the electrode spacings (1/2AB) on a log-log scale to obtain the VES sounding curves
using an appropriate computer software IPI2win in the present study. Some sounding curves and their models are
shown in Fig.3. Similarly, geoelectric sections are shown in Figs. 4 and 5.Three resistivity sounding curve types
were obtained from the studied area and these are the H (ρ1>ρ2<ρ3), A (ρ1< ρ2<ρ3) and KH (ρ1>ρ2< ρ3>ρ4) type
curves. However, there are few points which show two geologic layer cases. The results of the interpreted VES
curves are shown in Tables 1 and 2. The modeling of the VES measurements carried out at eighteen (18) stations
has been used to derive the geoelectric sections for the various profiles (Figure 4 and 5). These have revealed
that there are mostly four and three geologic layers beneath each VES station, and two layer cases at three
different VES points. The geologic sequence beneath the study area is composed of top soil, weathered
basement, partly weathered/fractured basement, and fresh basement. The topsoil is composed of clayey-sandy
and sandy-lateritic hard crust with resistivity values ranging from 26 m to 391 m and thickness varying from
0.38m to 6.58m, thinnest at VES 12 and thickest at VES 13. It is however, observed from the geoelectric
sections that VES 10, 11, 12 and 13 are characterized with low resistivity values varying between 26 m to
99 m suggesting the clayey nature of the topsoil in these areas and possibly high moisture content. The second
layer is the weathered basement with resistivity values varying from 77 m to 391 m and thickness ranges
between 1.1m to 33.04m, thinnest at VES 16 and thickest at VES 6. The third layer is the partly weathered and
fractured basement with resistivity and thickness values varying between 473 m to 708 m and 5.86m to 34.1m
19
4. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
respectively. The layer is extensive and thickest at VES 18 and thinnest at VES 16. The fourth layer is
presumably fresh basement whose resistivity values vary from 1161 m to 3600 m with an infinite depth.
Though the thickness of the bedrock is assumed to be infinite, the depth from the earth’s surface to the bedrock
surface varies between 2.65m to 37.75m. Quite a few of the profiles dipping and a negligible number of them
show synclinal and fractured structure. These formations have some geological, physical and near-surface
engineering significance.
6.1 Profile A-A’
Profile A-A’ geoelectric section suggests that the site is characterized by lateritic hard pan at different
consolidation levels within shallow depths, while gneiss and granites mainly, characterize the basements (Fig.4).
The fresh basements have synclinal structure which cut across the profile. The weathered/fractured basement has
a dipping layering. The probable feature that may cause building failure could be geologic feature like dipping
bedrock or synclinal structure. This is because while overburden materials fill the synclinal structure, their
columns undergo ground movement by subsidence and thereby could amount to uneven settlement at the
foundation depths of buildings. In other words, uneven stress distribution may occur at the foundation depths of
subsurface, that is one side of building structure may have a stronger support than the other adjacent of it.
Another factor that could contribute to structural defect of building is the seasonal variation in the saturation of
clay which causes ground movement and is caused by clay swells and shrinkages which are occasioned by
alternate wet and dry seasons. The area is characterized by clay soils with lateritic patches at shallow depths with
their thickness ranging between 1.06m and 4.14m.
6.2 Profile B-B’
The geoelectric section revealed clayey sandy topsoil having some lateritic hard crust patches (Fig. 5). The
synclinal structure at VES point 11 is not well pronounced and may not pose any serious danger to building
foundation. However, there is a deep weathering beneath VES point 17 and 18. The presence of laterite beneath
the clayey topsoil which hardly extends beyond 2.5m reduces the danger posed by clay formation to large
buildings. This area forms a good site for the erection of high-rise civil engineering structures.
6.3 Competence Evaluation
There are no indications of any major linear structure such as fracture or faults that could aid building
subsidence. The geologic sequence beneath the area is composed of thin layer of topsoil, thick weathered layer,
partly weathered/fractured basement and fresh bedrock. The topsoil constitutes the layer within which small civil
engineering structures can be constructed. From the table of resistivity values Table 1, the topsoil is composed of
sandy clay, clayey sand and patches of lateritic hard pans. Engineering competence of the subsurface can be
qualitatively evaluated from the layer resistivity. The higher the layer resistivity value, the higher the
competence of a layer; hence from the point of view of the resistivity value therefore, laterite is the most
competent of the delineated topsoil, followed by clayey sand and sandy clay being the least competent. Based on
the resistivity values, depths of about 8-10m can support small to medium size structures while depth in excess
of 25m can support massive civil engineering structures in the study area.
6.4 Groundwater Potential
Even though experience has shown that there is no direct relationship between groundwater yield and borehole
depth in a basement complex environment, studies (Bala and Ike, 2001; Omosuyi et al., 2008; Ariyo and
Osinawo, 2007) revealed that areas with thick overburden cover in such basement complex terrain has high
potential for groundwater. According to Ariyo and Oguntade (2009), in a basement complex terrain, areas with
overburden thickness of 15m and above are good for groundwater development. The highest groundwater yield
is often obtained from a weathered/fractured aquifer, or simply a subsurface sequence that has a combination of
a significantly thick and sandy weathered layer and fractured aquifer. Where the bedrock is not fractured, a
borehole can be located at a point having a relatively high layer resistivity greater than 150 m but less than
600 m (Olorunfemi, 2009). From the foregoing two parameters – overburden thickness and resistivity values,
VES 1, 2, 3, 4, 5, 6, 7, 17 and 18 can be considered to be productive zones for groundwater development in the
study area. Since the area is generally shallow to the water aquifer and groundwater in this area is vulnerable to
pollution, the depth of sewage system should be <10m to the weathered basement (aquiferrous zone) in order to
avoid groundwater contamination. It is suggested that potential sources of contamination site like sewage
channels should be sited far away from viable aquifer units to ensure safety consumption of groundwater within
the area.
7. Conclusion
The VES results revealed heterogeneous nature of the subsurface geological sequence. Though the geoelectric
section showed complexity in the subsurface lithology, there is however, no indication of any major
fracture/fault that could aid subsidence. The geologic sequence beneath the study area is composed of topsoil,
20
5. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
weathered layer, partly weathered/fractured basement, and fresh basement. The topsoil is composed of
clayey-sandy and sandy-lateritic hard crust with resistivity values ranging from 26 m to 391 m and thickness
varying from 0.38m to 6.58m, thinnest at VES 12 and thickest at VES 13. It is however, observed from the
geoelectric sections that VES 10, 11, 12 and 13 are characterized with low resistivity values varying between
26 m to 99 m suggesting the clayey nature of the topsoil in these areas and possibly high moisture content.
The second layer is the weathered basement with resistivity values varying from 77 m to 391 m and thickness
ranges between 1.1m to 33.04m, thinnest at VES 16 and thickest at VES 6. The third layer is the partly
weathered and fractured basement with resistivity and thickness values varying between 473 m to 708 m and
5.86m to 34.1m respectively. The layer is extensive and thickest at VES 18 and thinnest at VES 16. The fourth
layer is presumably fresh basement whose resistivity values vary from 1161 m to 3600 m with an infinite
depth. Though the thickness of the bedrock is assumed to be infinite, the depth from the earth’s surface to the
bedrock surface varies between 2.65m to 37.75m. A-curve type which shows a continuous and uniform increase
in resistivity predominates. This curve typifies an area showing characteristics of high load-bearing strength.
This is followed by HK-curve showing that some areas have overburden saturation which recharges the main
aquifer units. The rest of the curves are minority in number with H-type curve which has a minimum resistivity
intermediate layer underlain and overlain by more resistant materials reminiscent of areas promising for
groundwater development and also few 2-layer cases close to the bedrock are observed. Based on the resistivity
values of the different geoelectric layers, the various geologic units up to depth of 25m are competent and can
support massive civil engineering structures. The presence of laterite beneath the clayey topsoil which hardly
extends beyond 2.5m reduces the danger posed by clay formation to large buildings. Other probable causes of
foundation defects are the growth of tree roots, organic deposits, sink holes, cavities or ground surface saturation
due to seepages and this should be taken care of during building project implementation to ensure that buildings
erected at the site stands the test of time. In a basement complex terrain, areas with overburden thickness of
15m and above are good for groundwater development. The highest groundwater yield is often obtained from a
weathered/fractured aquifer, or simply a subsurface sequence that has a combination of a significantly thick and
sandy weathered layer and fractured aquifer. Where the bedrock is not fractured, a borehole can be located at a
point having a relatively high layer resistivity greater than 150 m but less than 600 m (Olorunfemi, 2009).
From the foregoing two parameters – overburden thickness and resistivity values, VES 1, 2, 3, 4, 5, 6, 7, 17 and
18 can be considered to be productive zones for groundwater development in the study area. To ensure safety
appraisal of groundwater consumption in the area, potential sources of contamination site should be sited far
away from viable aquifer units to ensure safety consumption of groundwater within the study area.
Acknowledgement
The field guide and contributions of Dr. B.S Jatau technically and financially cannot be over emphasized. His
supports, corrections and guides are gratefully acknowledged, you are indeed a good mentor. Words of wisdom
and encouragement from my fathers and mentors in geology matters, the likes of Prof. S. Abaa and Prof. N.G.
Obaje also make this paper work a huge success.
21
6. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
References
Ariyo, S.O. and Oguntade, A.K. (2009). Geophysical Investigation for Groundwater Potential in
Mamu Area, Southwestern Nigeria. Medwell Online Journal of Earth Sciences, Vol.3, no.1, pp.10-13.
Ariyo, S.O. and Osinawo, O.O. (2007). Hydrogeophysical Evaluation of Groundwater Potentials of
Atan/Odosenbora. Medwell Online Journal of Earth Sciences, Vol.9, no.1, pp. 50-65.
Bala, A.E. and Ike, E.C. (2001). The Aquifer of the Crystalline Basement Complex Area of Africa. Quarterly
Journal of Engineering Geology, Vol.18, pp. 35-36.
Burger, R.H (1992), ‘Exploration Geophysics of the Shallow Subsurface’. Prentice Hall, U.S.A. pp. 30-56
Blyth, F.G.H and de Freitas, M.D., (1988). Geology for Engineers. Butler and Tannar Ltd, Frome and
London. Pp. 292-293.
Burland, J.B and Burbidge, M.C (1981). Settlement of Foundations on Sand and Gravel Proceedings of
the Institution of Civil Engineers, 78(1), pp. 1325- 1381.
Goh, C.L., and Adeleke, B.O., (1978). Certificate Physical and Human Geography’ Oxford University Press,
Ibadan,pp78-150.
Hore, P.N (1970). Weather and Climate of Zaria and its Region. (Ed.) By M.J. Mortimore, Department of
Geography, Occasional Paper No4. A.B.U. Zaria. pp. 41-54
McCurry, P. O. (1970). The Geology of Zaria sheet 102 S.W and its Region in Mortimore, M.J. (Ed).
Department of Geography occasional paper No.4, Ahmadu Bello University, Zaria. pp. 1-3.
McLeod W.N.; Turner D.C. and Wright, E.P. (1971). The Geology of Jos Plateau with 1:100,000 Sheets
147,148,168,169,189 and 190. Geol. Survey Nigeria Bulletin, 32.
Omosuyi, G.O., Ojo, J.S. and Enikanoselu, P.A. (2003). Geophysical Investigation for Groundwater around
Obanla-Obakekere in Akure Area within the Basement Complex of South-western Nigeria. Journal of
Mining and Geology, Vol.39, no.2, pp. 109-116.
Okolie, E.C., Osemeikhian, J.E.A., Oseji, J.O. and Atakpo, E. (2005). Geophysical Investigation of the Source of
River Ethiope in Ukwuani Local Government Area of Delta State. Nigerian Institute of Physics, Vol.17,
pp.30-45.
Olorunfemi M.O. (2009). Water resources, Groundwater Exploration, Borehole site selection, and Optimum
Drill Depth in Basement Complex Terrain: Journal of the Nigerian Association of Hydrogeologists.
Special Publication Series 1, pp. 1-20.
Omoyoloye, N.A., Oladapo, M.I. and Adeoye, O.O., (2008). Engineering Geophysical Study of Adagbakuja
Newtown Development, Southwestern Nigeria. Medwell Online Journal of Earth Science; Vol. 2(2);
pp. 55-63
Oseji, J.O., Atakpo, E. and Okolie, E.C. (2005). Geoelectric Investigation of the Aquifer Characteristics and
Groundwater Potential in Kwale, Delta State. Nigerian Journal of Applied Sciences and Environmental
Management, Vol.9, pp. 157-1600.
Oyawoye, M.O (1970). The Basement Complex of Nigeria. In: Dessauvagie, TFJ and White man, A.J (Eds)
African Geology. University Press, Ibadan Nigeria pp. 91-97.
Rahaman, M.A. (1976).Review of the Basement Geology of South western Nigeria. In: Kogbe (Ed.). Geology
of Nigeria, Elizabeth Publishing Company Lagos pp 41-58.
22
7. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
Figure 1: Location Map Showing the Study Area (From Northern Nigerian Survey Map)
Study Area
23
8. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
Table 1: The results of the interpreted VES curves
24
9. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
r1 r2
Earth’s surface
A M N B
r3 r4
Figure 2: Four-general electrode configuration (Shlumberger Array).
25
10. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
26
11. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
VES VES 2 VES 4 VES VES VES VES 8 VES 9
1 VES 3 5 6 7
A A’
373 ࢹ 370 ࢹ 276 ࢹ 304 ࢹ 365 ࢹ 353 ࢹ
257 ࢹ 272 ࢹ
367 ࢹ
ࢹ
59 ࢹ 708ߗ݉
298 ࢹ
351 ࢹ 228 ࢹ
77 ࢹ
10
3115 ࢹ
1765 ࢹ
144 ࢹ
391 ࢹ
DEPTH (m)
473 ࢹ
20
834 ࢹ
522 ࢹ
1362 ࢹ
503 ࢹ
30
1251 ࢹ
1410 ࢹ 1450 ࢹ
40
Lateritic hard pan (Top soil) Weathered layer
Partly weathered/fractured layer Fresh basement
27
12. Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol 2, No.7, 2012
Figure 4: Geoelectric section along profiles A-Ai
VES 10 VES 11 VES 12 VES 13 VES 14 VES 15 VES 16 VES 17 VES 18
B’
B 28 ࢹ 281 ࢹ 256 ࢹ
26 ࢹ
28 ࢹ 30 ࢹ 30 ࢹ 254 ࢹ
316 ࢹ 347 ࢹ 358 ࢹ
356 ࢹ
261 ࢹ
162 ࢹ 199 ࢹ
519 ࢹ
694 ࢹ
302 ࢹ 3699 ࢹ 2593 ࢹ
3307 ࢹ
1270 ࢹ
2935 ࢹ
10
1519 ࢹ 658 ࢹ
1410 ࢹ
DEPTH (m)
20
30
1614 ࢹ
40
3511 ࢹ
Clay/clayey sandy (Top soil) Lateritic hard pan (Top soil)
Weathered layer Partly weathered/fractured layer
Fresh basement
Figure 5: Geoelectric section along profiles B-Bi
28
13. This academic article was published by The International Institute for Science,
Technology and Education (IISTE). The IISTE is a pioneer in the Open Access
Publishing service based in the U.S. and Europe. The aim of the institute is
Accelerating Global Knowledge Sharing.
More information about the publisher can be found in the IISTE’s homepage:
http://www.iiste.org
The IISTE is currently hosting more than 30 peer-reviewed academic journals and
collaborating with academic institutions around the world. Prospective authors of
IISTE journals can find the submission instruction on the following page:
http://www.iiste.org/Journals/
The IISTE editorial team promises to the review and publish all the qualified
submissions in a fast manner. All the journals articles are available online to the
readers all over the world without financial, legal, or technical barriers other than
those inseparable from gaining access to the internet itself. Printed version of the
journals is also available upon request of readers and authors.
IISTE Knowledge Sharing Partners
EBSCO, Index Copernicus, Ulrich's Periodicals Directory, JournalTOCS, PKP Open
Archives Harvester, Bielefeld Academic Search Engine, Elektronische
Zeitschriftenbibliothek EZB, Open J-Gate, OCLC WorldCat, Universe Digtial
Library , NewJour, Google Scholar