This document summarizes the results of two vertical electrical soundings (VES) conducted in Benin City, Nigeria to determine aquifer depths. VES 1 identified a six-layer structure with the water-bearing formation found at a depth of 17.98m. VES 2 identified a five-layer structure with the water-bearing formation at a depth of 32.43m. The resistivity method was used to measure subsurface resistivity values at increasing electrode separations. Lithological interpretations identified sand and clayey sand formations, with the deepest formations comprised of water-bearing sand aquifers.
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.
Hydrogeological assessment of two important wetlands (GDEs) in Hodgson's Wetl...getnathans
This document summarizes a study of two wetlands, W023 and W024, located within the Buntine-Marchagee Natural Diversity Recovery Catchment in Western Australia. The study analyzed the regional geology, hydrogeology, and water balances of the wetlands. For both wetlands, the major water inputs were horizontal groundwater inflow and surface water inflow, while the major outputs were horizontal groundwater outflow and evapotranspiration. The water and chloride balances showed that W023 had a surplus of 560 kg/year of chloride while W024 had a deficit of 310 cubic meters/year of water. The study provides insight into the hydrology and geochemistry of the two wetland systems.
The document summarizes a study on fatigue crack propagation life in a single edged notched beam. Finite element analysis was used to model the beam and predict fatigue life under different loads and stress ratios. Experimental testing was also conducted on physical specimens to validate the FEA results. The FEA and experimental results showed a linear relationship between fatigue life and stress ratio. The study demonstrated that FEA can accurately predict fatigue life and provide insight into fatigue damage phenomena in notched beams.
This document summarizes research on heterojunction diodes fabricated from germanium-tin (GeSn) alloys grown by molecular beam epitaxy. The key points are:
1) Heterojunction diodes of p-type GeSn and n-type germanium were fabricated with GeSn tin contents up to 9%.
2) Electrical measurements of the current-voltage characteristics showed the diodes had good rectifying behavior with low turn-on voltages.
3) Analysis of the diode parameters, such as reverse saturation current and series resistance, showed these increased with higher tin content in the GeSn layer. This suggests higher tin content results in higher conductivity in the diodes.
This document summarizes a case study that used geophysical methods to characterize focused seepage through an earthfill dam. Resistivity and self-potential tomography were used to investigate anomalous seepage. The self-potential signals provide information about groundwater flow patterns because the source current density responsible for the SP signals is proportional to the Darcy velocity. However, the resistivity distribution also influences the SP distribution, so resistivity and SP data need to be used together. The study conducted resistivity and SP surveys at a dam in Colorado experiencing anomalous seepage at the toe. The data revealed SP and resistivity anomalies that were used to delineate three anomalous seepage zones and estimate the source of localized seepage
Measurement of Salinity and Electrical Conductivity of Land Forms in Akwa Ibo...iosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Application of electrical resistivity tomography (ert) and arial photographs ...Alexander Decker
1. The document describes a study using electrical resistivity tomography (ERT) and aerial photographs to identify karst features like sinkholes at three construction sites in Perak, Malaysia.
2. ERT surveys found anomalies indicating saturated clay and possible sinkholes at the first site, several sinkholes and clay zones at the second site, and multiple soil collapse sinkholes and clay zones at the third site.
3. The study aims to locate karst features, estimate bedrock depth, and characterize the features to inform construction planning and mitigate geohazards at the sites.
The document reports on a study of the AC and DC conductivity of three glycine family nonlinear optical (NLO) single crystals: Trisglycine Zinc Chloride (TGZC), Triglycine Acetate (TGAc), and Glycine Lithium Sulphate (GLS). The AC conductivity was measured from 50 Hz to 5 MHz and increased with temperature for all crystals. The activation energies calculated from the AC conductivity were 0.035 eV for TGZC, 0.075 eV for TGAc, and 0.10 eV for GLS. The DC conductivity also increased with temperature from 313 K to 423 K, and the activation energies calculated were 0.050 eV for TGZC, 0.060 eV
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.
Hydrogeological assessment of two important wetlands (GDEs) in Hodgson's Wetl...getnathans
This document summarizes a study of two wetlands, W023 and W024, located within the Buntine-Marchagee Natural Diversity Recovery Catchment in Western Australia. The study analyzed the regional geology, hydrogeology, and water balances of the wetlands. For both wetlands, the major water inputs were horizontal groundwater inflow and surface water inflow, while the major outputs were horizontal groundwater outflow and evapotranspiration. The water and chloride balances showed that W023 had a surplus of 560 kg/year of chloride while W024 had a deficit of 310 cubic meters/year of water. The study provides insight into the hydrology and geochemistry of the two wetland systems.
The document summarizes a study on fatigue crack propagation life in a single edged notched beam. Finite element analysis was used to model the beam and predict fatigue life under different loads and stress ratios. Experimental testing was also conducted on physical specimens to validate the FEA results. The FEA and experimental results showed a linear relationship between fatigue life and stress ratio. The study demonstrated that FEA can accurately predict fatigue life and provide insight into fatigue damage phenomena in notched beams.
This document summarizes research on heterojunction diodes fabricated from germanium-tin (GeSn) alloys grown by molecular beam epitaxy. The key points are:
1) Heterojunction diodes of p-type GeSn and n-type germanium were fabricated with GeSn tin contents up to 9%.
2) Electrical measurements of the current-voltage characteristics showed the diodes had good rectifying behavior with low turn-on voltages.
3) Analysis of the diode parameters, such as reverse saturation current and series resistance, showed these increased with higher tin content in the GeSn layer. This suggests higher tin content results in higher conductivity in the diodes.
This document summarizes a case study that used geophysical methods to characterize focused seepage through an earthfill dam. Resistivity and self-potential tomography were used to investigate anomalous seepage. The self-potential signals provide information about groundwater flow patterns because the source current density responsible for the SP signals is proportional to the Darcy velocity. However, the resistivity distribution also influences the SP distribution, so resistivity and SP data need to be used together. The study conducted resistivity and SP surveys at a dam in Colorado experiencing anomalous seepage at the toe. The data revealed SP and resistivity anomalies that were used to delineate three anomalous seepage zones and estimate the source of localized seepage
Measurement of Salinity and Electrical Conductivity of Land Forms in Akwa Ibo...iosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Application of electrical resistivity tomography (ert) and arial photographs ...Alexander Decker
1. The document describes a study using electrical resistivity tomography (ERT) and aerial photographs to identify karst features like sinkholes at three construction sites in Perak, Malaysia.
2. ERT surveys found anomalies indicating saturated clay and possible sinkholes at the first site, several sinkholes and clay zones at the second site, and multiple soil collapse sinkholes and clay zones at the third site.
3. The study aims to locate karst features, estimate bedrock depth, and characterize the features to inform construction planning and mitigate geohazards at the sites.
The document reports on a study of the AC and DC conductivity of three glycine family nonlinear optical (NLO) single crystals: Trisglycine Zinc Chloride (TGZC), Triglycine Acetate (TGAc), and Glycine Lithium Sulphate (GLS). The AC conductivity was measured from 50 Hz to 5 MHz and increased with temperature for all crystals. The activation energies calculated from the AC conductivity were 0.035 eV for TGZC, 0.075 eV for TGAc, and 0.10 eV for GLS. The DC conductivity also increased with temperature from 313 K to 423 K, and the activation energies calculated were 0.050 eV for TGZC, 0.060 eV
1-D Electrical Resistivity Survey For Groundwater In Ketu-Adie Owe, Ogun Stat...iosrjce
This research involved the use of 1-D electrical resistivity survey method for groundwater
investigation in Ketu-Adie Owe, Ogun State. Seven (7) vertical electrical resistivity soundings (VES) using
Schlumberger array were carried out at different locations. The Schlumberger resistivity soundings were
executed with half-spacing in the range of 1.00 – 100.00 metres. The curve types are AAK, AAK, KHAK, AKQ,
KQH, AK. The study shows that viable aquifer is within 17.30 – 52.90 metres square.
Electrical resistivity data interpretation for groundwater detection in titta...eSAT Journals
Abstract The present study aims to detect the groundwater potential in Tittagudi Taluk of Cuddalore District, Tamil Nadu, India using electrical measurement. Electric resistivity data interpretation was carried out using Schlumberger configuration with electrode spacing (AB/2) of 100 m distance. The VES was calculated by multiplying the resistance by constant obtained from the Schlumberger formula. The resistivity curves were analysed with curve matching techniques along with the help of computer programme. The sub-surface lithology was evaluated and correlated with the available borehole data. The results of quantitative interpretation of geoelectrical data indicated that the layer system having minimum of two layers to a maximum of eight layers in the area. The low and high resistivities obtained are ranging from 0.5 to 27755 ohm/m respectively. Majority of resistivity curves are falling in ‘A’ type. The contact zone of sedimentary and crystalline rock formations are clearly delineated on Northeast to Southwest directions along Sirumangalam, Agaram and Sirumalai habitations. The prominent low resistivity anomaly observed in and around Adari area (VES. 03), this have been encountered in all the iso-resistivity contour maps, indicating that, a trend of structural elements like a weaker zone or lineament or fracture occurred in NE direction of the study area which may be a favorable zone for targeting groundwater. Key words: Electrical Measurements, Tittagudi Taluk, Schulmberger Configuration And Iso-Resistivity Maps.
Partially filled electrode for DMF devicesWaleed Salman
This document describes research into partially filled electrodes for digital microfluidic devices. The researchers conducted simulations and experiments to evaluate how reducing the filled area of electrodes affects actuation forces on droplets. The simulations showed that actuation force decreases linearly as electrode fill percentage decreases. However, forces were independent of the vertical location of removed electrode areas. Experiments confirmed that partially filled electrodes can still achieve droplet actuation speeds sufficient for many applications, with frequencies over 10 electrodes per second achieved at 40% fill area. Partially filled electrodes also allow integration of additional on-chip elements and transmission microscopy imaging of droplets.
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
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.
- Mesoporous glasses can have their bandgap tuned by manipulating the stress in the glass network through thermal annealing. The stress arises from the mismatch in thermal expansion between the pore walls and pores.
- Higher annealing temperatures increase the stress in a mesoporous (TiO2)1-x(SiO2)x glass, widening its bandgap from 3.74 eV to 4.02 eV.
- This physical method of bandgap tuning could enable applications in photocatalysis by allowing optimization of the material for different light wavelengths without chemical doping.
The document discusses a geo-electrical imaging survey conducted in Edo State, Nigeria to characterize the subsurface geology for environmental and engineering studies. Resistivity data was collected along four lines using the Wenner array and inverted to produce 2D resistivity images. The images indicate resistivity increases with depth and identify three main layers - alluvium deposits from 0-20m underlain by laterite to 20m thick, underlain by sandstone and shale. Areas over 3500 ohm-m represent bedrock of gravel and granite, showing the area is suitable for construction. The study found no evidence of contamination or faults, but low conductivity suggests limited aquifer potential for water supply.
Application of vertical electrical sounding and horizontal profiling methods ...Alexander Decker
The document describes a study that used vertical electrical sounding (VES) and horizontal profiling (EP) methods to characterize the subsurface stratification at a proposed dam site on the Segen River in Tigray, Northern Ethiopia. Ten VES points were collected along two profiles, and two EP surveys were conducted along the profiles. The VES and EP results identified weak zones up to 20-30 meters deep at several locations along the profiles, indicating the need for further core drilling investigations to properly evaluate the subsurface conditions for dam construction.
Geoelectric Investigation of Groundwater Potential of Ihiala and Its Environ,...iosrjce
IOSR Journal of Applied Geology and Geophysics (IOSR-JAGG) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of Applied Geology and Geophysics. The journal welcomes publications of high quality papers on theoretical developments and practical applications in Applied Geology and Geophysics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Application Of Resistivity For Groundwater, Hydrogeology and Pollution ResearchOmokpariolaElshalom
It was a group seminar geophysics course presentation in my year 3 of which I was asked to represent the group in giving an oral presentation of how we can apply resistivity in the geophysical investigation of groundwater, pollution ansd hydrogeology.
Moisture content investigation in the soil samples using microwave dielectric...IJECEIAES
The microwaves of typical frequency ranges of 3 GHz to 30 GHz have been in use for remote sensing applications which are progressing rapidly. The microwaves can sense existing moisture in any material that absorbs moisture such as soil or vegetation. In case of soils which may be comprised of variable mix proportionate of solids, liquids or gases and distinct textures subjected to the associated size and the arrangements of soil particles. Hence, the moisture absorption by a specific type of soil used to be different. The inherent physical and electrical properties such as color, texture, grains, dielectric constant, conductivity or permeability, etc. differentiate various soils. In this work, authors present soil moisture measurement by simple estimation of emissivity i.e. the ratio of energy radiated by an object to absorbing the body of same physical temperature. A strategic method of measuring dielectric constant using a microwave signal is used in this research work. The measurement of the dielectric constant of the soils collected from the specific regions and analysis of results has been reported. The proposed method is less complex and can further be used for the identification of soil moisture and agricultural applications.
Geohydraulic parameters are essential elements in groundwater resource management and conservation.
Most of these parameters especially the hydraulic conductivity and transmissivity are usually estimated
from pumping test carried out on drilled boreholes. This paper presents a study conducted in Abi area of
the Ikom-Mamfe Embayment with the objective of estimating aquifer parameters from 30 evenly
distributed vertical electrical soundings using the Schlumberger configuration and hydrogeologic
measurements from 28 boreholes within the area as an alternative way of generating an initial data
for groundwater characterisation and quality assessment in the area. The results showed low resistivity
645 Xm, hydraulic conductivity 62.0 105 m/s (61.7 m/day) and transmissivity 65.2 104 m2/s
(645 m2/day) for the water-bearing aquifer horizons in the northeastern and northwestern parts of
the study area due to the nature of the aquifer system that were predominantly fractured shale. The sand
based aquifers had higher values in the neighbourhood of 100–800 Xm, 4.0 105–1.0 104 m/s
(3.46–9.04 m/day) and 6.94 104–3.81 103 m2/s (60–330 m2/day) for the respective parameters
mentioned above. The potability of the groundwater system as observed from hydrogeologic measurements
of water samples from most boreholes were relatively poor, having electrical conductivity
and total dissolved solids values of 250–931.0 lS/cm and 500–623.77 mg/l respectively due to the
influence of clay minerals within the aquifer horizon. Some of the vertical electrical sounding points were
taken in the vicinity were pumping tests and lithologic data were available for adequate comparison of
the results.Electrical resistivity
Geohydraulic parameters
Groundwater
Hydraulic conductivity
Ikom-Mamfe Embayment
Abi-Nigeria
Evaluation of sub-soil geo-electric properties in a proposed power sub-statio...IJERA Editor
This document summarizes the results of an electrical resistivity survey conducted at a proposed power substation site in Rivers State, Nigeria. The survey found that the subsurface is characterized by two main geo-electric layers: an upper layer of lower resistivity lateritic to silty sands extending to depths of 2-3 meters, and a lower layer of higher resistivity fine to coarse sands and gravels forming the major aquifers in the area. Analysis showed that the subsoil falls within the non-corrosive class, indicating that subsurface electrical installations would pose minimal hazards with basic precautions.
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.
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.
Groundwater investigation using geophysical methods a case study of pydibhim...eSAT Publishing House
This document summarizes the results of a geophysical investigation using vertical electrical sounding (VES) methods at 13 locations around an industrial area in India. The VES data was interpreted to generate geo-electric sections and pseudo-sections showing subsurface resistivity variations. Three main layers were typically identified - a high resistivity topsoil, a weathered middle layer, and a basement rock. Pseudo-sections revealed relatively more weathered areas in the northwest and southwest. Resistivity sections helped identify zones of possible high groundwater potential based on low resistivity anomalies sandwiched between more resistive layers. The study concluded the electrical resistivity method was useful for understanding subsurface geology and identifying areas prospective for groundwater exploration.
Effect of alpha irradiation on silicon schottky diode detectoreSAT Journals
Abstract This paper gives a brief overview of Semiconductor Schottky diode detector in response to α-particle irradiation. As α-particle are difficult to detect so we need a high resolution device for its detection. In this paper we have simulated a model of Si Schottky diode detector in Sentaurus TCAD Software. TCAD (Technology Computer Aided Design) simulation is a boon for the semiconductor devices. Using this tool we can simulate and design semiconductor devices and can generate simulation model to get the best optimum simulation results for semiconductor diode. Sentaurus TCAD supports wide range of semiconductor technologies from conventional to compound semiconductor detector. α-particles induced transient current pulse measurement were carried out on Si Schottky diode at (1) different temperature, (2) different energies of the incident α-particle and (3) different reverse bias of Schottky diode. Effect of temperature, incident α-particle and reverse bias on the generated α- induced transient current pulse were analyzed. Keywords: Semiconductor Schottky diode, Single event transient (SET), α particle, reverse bias, Sentaurus TCAD
THE STUDY ON THE PLASMA GENERATOR THEORY FOR THIN DISC AND THIN RING CONFIGUR...AM Publications
Various corona discharges plasma generators equipment have been composed with significant ability to produce saturation current effect. The effect was generated by the potential difference of the capacitive system where two electrodes are set with opposite charges to each other. The saturation current occurring in this capacitive electrode system can be generated by a small voltage source (about 12 volts). A sufficiently large electric field and a saturation current, can be obtained from a configuration of sharp electrodes. An example of the electrode shape is a configuration of a very thin and sharp disc surrounded by a ring electrode in a two-dimensional space. The value of the electric field and the saturation current will be calculated in mentioned electrode configuration.
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.
1-D Electrical Resistivity Survey For Groundwater In Ketu-Adie Owe, Ogun Stat...iosrjce
This research involved the use of 1-D electrical resistivity survey method for groundwater
investigation in Ketu-Adie Owe, Ogun State. Seven (7) vertical electrical resistivity soundings (VES) using
Schlumberger array were carried out at different locations. The Schlumberger resistivity soundings were
executed with half-spacing in the range of 1.00 – 100.00 metres. The curve types are AAK, AAK, KHAK, AKQ,
KQH, AK. The study shows that viable aquifer is within 17.30 – 52.90 metres square.
Electrical resistivity data interpretation for groundwater detection in titta...eSAT Journals
Abstract The present study aims to detect the groundwater potential in Tittagudi Taluk of Cuddalore District, Tamil Nadu, India using electrical measurement. Electric resistivity data interpretation was carried out using Schlumberger configuration with electrode spacing (AB/2) of 100 m distance. The VES was calculated by multiplying the resistance by constant obtained from the Schlumberger formula. The resistivity curves were analysed with curve matching techniques along with the help of computer programme. The sub-surface lithology was evaluated and correlated with the available borehole data. The results of quantitative interpretation of geoelectrical data indicated that the layer system having minimum of two layers to a maximum of eight layers in the area. The low and high resistivities obtained are ranging from 0.5 to 27755 ohm/m respectively. Majority of resistivity curves are falling in ‘A’ type. The contact zone of sedimentary and crystalline rock formations are clearly delineated on Northeast to Southwest directions along Sirumangalam, Agaram and Sirumalai habitations. The prominent low resistivity anomaly observed in and around Adari area (VES. 03), this have been encountered in all the iso-resistivity contour maps, indicating that, a trend of structural elements like a weaker zone or lineament or fracture occurred in NE direction of the study area which may be a favorable zone for targeting groundwater. Key words: Electrical Measurements, Tittagudi Taluk, Schulmberger Configuration And Iso-Resistivity Maps.
Partially filled electrode for DMF devicesWaleed Salman
This document describes research into partially filled electrodes for digital microfluidic devices. The researchers conducted simulations and experiments to evaluate how reducing the filled area of electrodes affects actuation forces on droplets. The simulations showed that actuation force decreases linearly as electrode fill percentage decreases. However, forces were independent of the vertical location of removed electrode areas. Experiments confirmed that partially filled electrodes can still achieve droplet actuation speeds sufficient for many applications, with frequencies over 10 electrodes per second achieved at 40% fill area. Partially filled electrodes also allow integration of additional on-chip elements and transmission microscopy imaging of droplets.
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
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.
- Mesoporous glasses can have their bandgap tuned by manipulating the stress in the glass network through thermal annealing. The stress arises from the mismatch in thermal expansion between the pore walls and pores.
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Most of these parameters especially the hydraulic conductivity and transmissivity are usually estimated
from pumping test carried out on drilled boreholes. This paper presents a study conducted in Abi area of
the Ikom-Mamfe Embayment with the objective of estimating aquifer parameters from 30 evenly
distributed vertical electrical soundings using the Schlumberger configuration and hydrogeologic
measurements from 28 boreholes within the area as an alternative way of generating an initial data
for groundwater characterisation and quality assessment in the area. The results showed low resistivity
645 Xm, hydraulic conductivity 62.0 105 m/s (61.7 m/day) and transmissivity 65.2 104 m2/s
(645 m2/day) for the water-bearing aquifer horizons in the northeastern and northwestern parts of
the study area due to the nature of the aquifer system that were predominantly fractured shale. The sand
based aquifers had higher values in the neighbourhood of 100–800 Xm, 4.0 105–1.0 104 m/s
(3.46–9.04 m/day) and 6.94 104–3.81 103 m2/s (60–330 m2/day) for the respective parameters
mentioned above. The potability of the groundwater system as observed from hydrogeologic measurements
of water samples from most boreholes were relatively poor, having electrical conductivity
and total dissolved solids values of 250–931.0 lS/cm and 500–623.77 mg/l respectively due to the
influence of clay minerals within the aquifer horizon. Some of the vertical electrical sounding points were
taken in the vicinity were pumping tests and lithologic data were available for adequate comparison of
the results.Electrical resistivity
Geohydraulic parameters
Groundwater
Hydraulic conductivity
Ikom-Mamfe Embayment
Abi-Nigeria
Evaluation of sub-soil geo-electric properties in a proposed power sub-statio...IJERA Editor
This document summarizes the results of an electrical resistivity survey conducted at a proposed power substation site in Rivers State, Nigeria. The survey found that the subsurface is characterized by two main geo-electric layers: an upper layer of lower resistivity lateritic to silty sands extending to depths of 2-3 meters, and a lower layer of higher resistivity fine to coarse sands and gravels forming the major aquifers in the area. Analysis showed that the subsoil falls within the non-corrosive class, indicating that subsurface electrical installations would pose minimal hazards with basic precautions.
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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.
Groundwater investigation using geophysical methods a case study of pydibhim...eSAT Publishing House
This document summarizes the results of a geophysical investigation using vertical electrical sounding (VES) methods at 13 locations around an industrial area in India. The VES data was interpreted to generate geo-electric sections and pseudo-sections showing subsurface resistivity variations. Three main layers were typically identified - a high resistivity topsoil, a weathered middle layer, and a basement rock. Pseudo-sections revealed relatively more weathered areas in the northwest and southwest. Resistivity sections helped identify zones of possible high groundwater potential based on low resistivity anomalies sandwiched between more resistive layers. The study concluded the electrical resistivity method was useful for understanding subsurface geology and identifying areas prospective for groundwater exploration.
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Abstract This paper gives a brief overview of Semiconductor Schottky diode detector in response to α-particle irradiation. As α-particle are difficult to detect so we need a high resolution device for its detection. In this paper we have simulated a model of Si Schottky diode detector in Sentaurus TCAD Software. TCAD (Technology Computer Aided Design) simulation is a boon for the semiconductor devices. Using this tool we can simulate and design semiconductor devices and can generate simulation model to get the best optimum simulation results for semiconductor diode. Sentaurus TCAD supports wide range of semiconductor technologies from conventional to compound semiconductor detector. α-particles induced transient current pulse measurement were carried out on Si Schottky diode at (1) different temperature, (2) different energies of the incident α-particle and (3) different reverse bias of Schottky diode. Effect of temperature, incident α-particle and reverse bias on the generated α- induced transient current pulse were analyzed. Keywords: Semiconductor Schottky diode, Single event transient (SET), α particle, reverse bias, Sentaurus TCAD
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1. Available online at www.pelagiaresearchlibrary.com
Pelagia Research Library
Advances in Applied Science Research, 2013, 4(6):268-276
ISSN: 0976-8610
CODEN (USA): AASRFC
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Analysis of electrical resistivity data for the determination of aquifer depth at
Sapele RD in Benin city
Molua O. Collins, Igherighe C. Edwin and Eseka Kenneth
Physics Department, College of Education, Agbor, Delta State, Nigeria
_____________________________________________________________________________________________
ABSTRACT
The importance of groundwater cannot be overemphasized. For this reason, the exploration for water and its
purification is therefore a vital aspect of Geophysics. The resistivity method of surveying was carried out for the
study of underground aquifer at Sapele road in Benin-City, Edo State, Nigeria. Data were acquired using the ABEM
Terrameter 300B using the Schlumberger array. Two locations were considered, and for each location, the vertical
electrical sounding was used to obtain readings for resistance and the apparent resistivities. The results obtained
showed that water bearing formation for the two survey areas, was found at depths of 17.98m for VES 1 and 32.43m
for VES 2.
Keywords: Aquifer, Sapele , Resistivity, Data, Electrical
_____________________________________________________________________________________________
INTRODUCTION
Electrical resistivity surveys are usually very useful and convenient when searching for groundwater and in the
exploration of mineral. It can also provide information about the subsurface formations when potential
measurements are taken at the surface.
The electrical resistivity method as a tool for geophysical exploration, is based on the fact that the underlying rock
materials can impose resistance to the flow of current and as such ohm’s law could be applied to them if the earth is
homogenous, the resistivity measured is called true resistivity otherwise, the term apparent resistivity is used and
this is a weighted average of the resistivities of the various formation.
The usual practice in resistivity survey measurements is to introduce current into the ground by means of two
current electrodes and potential drop is measured through a second pair of potential electrodes. The flow of current
within the earth is affected by subsurface formation and hence the distribution of electric potential.
Conduction of electricity in the ground occurs through the interstitial water present in the rock and which contains
some dissolved salts invariably. Low resistivity usually indicates the presence of water (clay) in the formation, this
is therefore as important as water salinity in establishing the true resistivity of a medium [1]
MATERIALS AND METHODS
The use of the electrical resistivity method as a geophysical tool for exploration is based on the flow of electric
current through the ground, and rock material. To allow the passage of current through the ground such a rock
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material should posses some form of electrical resistance, and be able by their nature to store charges. Therefore
some basic equations will necessarily relate these quantities. When we apply a voltage V across the ends of a body
of constant cross sectional area, the current I is proportional to the applied voltage (Ohm’s law). So that
V = IR or R =
I
V
Where R is the proportionality constant called the resistance of the body.
We also know that for a given material, the distance is proportional to its length and inversely proportional to the
cross sectional area A, of the body, so that
R = ρ L/A or ρ = RA/L
Where ρ , is the resistivity of the material, and has unit Ohm-metre (Ωm).
The vertical electrical sounding (VES) technique involves the use of electrical method, with depth control, in which
electrode spacing is increased to obtain information from greater depths at a given surface location [2]. It is used for
detecting changes with depth in the resistivity of the earth, beneath the given location. The principle of VES is based
on the fact that the wider the current electrode separation the deeper the current penetration.
Fig 1: diagram of Schlumberger electrode Array
The apparent resistivity is given by
ρ a = (∧ CD V/T) (L/CD) 2
– 0.25)
Where CD = distance between potential electrodes,
L = AB/2 = half the distance between current electrodes
AB is the distance between current electrodes. In this work, field measurement was taken at AB/2 = 1.00, 1.47, 2.15,
3.16, 4.64, 6.81, 10.00, 14.70, 21.50, 31.60, 46.40, 68.10, 100.00 and 147.00. A common initial value of CD is
0.15m and this is expanded gradually to satisfy the condition CD ≤ AB/2
Location of Study Area
This study was conducted in Sapele road in Benin-city metropolis. Benin-city is situated between latitude 60
15’ and
90
90’ N and longitude 60
11’ and 80
79’ E in Edo State, Nigeria. Benin-city metropolis is also known as Idu. It is
classified under the humid tropical rainforest zone. There are two distinct seasons characterized by seven months
(April – October) of wet season and five months (November – March) of dry season. Mean rainfall is 3,500mm
while temperature ranges from 2700
C -300
C.
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Local Geology
The area under study is underlain by basement complex rocks of precambrian to upper Cambrian age and cretaceous
to tertiary sedimentary rocks.
The basement complex comprises chiefly of undifferentiated basement rocks [3], undifferentiated Meta sediments
and older granite. In the sedimentary area there are five lithostratigraphic units observed. These are:
i. Nkporo shale group –consisting of shale & mudstone.
ii.Upper and lower coal measure –coal, sand stone and shale.
iii. Ajali formation –false bedded sandstones
iv. Imo clay –shale group –clays and shales with limestone
v. Bende amaki group – clay, clayey sands and shale.
The results of the two vertical electrical soundings obtained in the field are shown in tables 1 and 2 respectively. The
apparent resistivity values at each station were calculated using the equation below:
RESULTS AND DISCUSSION
VERTICAL ELECTRICAL SOUNDING (VES 1)
STATE: EDO
LGA: OREDO
DATE: 8/8/2010
OBSERVERS: MOLUA ET AL
WEATHER: HOT
ELECTRODE SYSTEM SCHLUMBERGER INSTRUMENT: PASI E2 DIGIT
SITE DESCRIPTION: BEHIND STATE SCHOOL OF NURSING (OFF SAPELE RD)
Table 1: VES 1
S/N
Electrode Separations
(AB/2) (m)
MN/2 (m)
Resistance (Ohms)
⋀⋁⋀⋁⋀⋁⋀⋁ = R
1
Geometric
Factors (k)
Apparent
Resisitvity (Ohm-m)
1 1.0 0.2 330.5 7.54 2492
2 1.47 0.2 127.0 16.66 2116
3 2.15 0.2 506.0 36.00 1823
4 3.16 0.2 186.0 78.1 1453
5 4.64 0.2 686.0 168.8 1158
6 6.81 0.2 238.0 364.0 866
7 6.81 1.4 167.0 49.85 832
8 10.0 0.2 143.0 785.0 1123
9 10.0 1.4 756.0 110.04 832
10 14.7 1.4 408.5 204.35 982
11 21.5 1.4 224.0 516.65 1157
12 31.6 1.4 108.0 1118.63 1208
13 31.6 6.0 524.0 552.0 1320
14 46.4 1.4 506.0 2414.39 1223
15 46.4 6.0 235.0 554.29 1303
16 68.1 6.0 115.0 1204.85 1386
17 100.0 6.0 530.0 2608.91 1383
18 100.0 2.0 187.0 764.29 1411
18 147.0 6.0 244.0 5633.15 1374
20 147.0 2.0 885.5 1666.42 1467
21 215.0 2.0 410.5 3600.54 1478
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VERTICAL ELECTRICAL SOUNDING (VES 2)
STATE: EDO
LGA: OREDO
DATE: 8/8/2010
OBSERVERS: MOLUA ET AL
WEATHER: HOT
BEARING: PARALLEL TO THE FIRST BUT 50m FROM IT (SADDLE)
ELECTRODE SYSTEM SCHLUMBERGER INSTRUMENT: PASI E2 DIGIT
SITE DESCRIPTION: BEHIND STATE SCHOOL OF NURSING (OFF SAPELE RD)
Table 2: VES 2
S/N
Electrode Separations
(AB/2) (m)
MN/2 (m)
Resistance (Ohms)
⋀⋁⋀⋁⋀⋁⋀⋁ = R
1
Geometric
Factors (k)
Apparent Resisitvity
(Ohm-m)
1 1.0 0.2 274.5 7.54 2070
2 1.47 0.2 143.0 16.66 2382
3 2.15 0.2 760.0 36.00 2736
4 3.16 0.2 400.0 78.1 3124
5 4.64 0.2 180.0 168.8 3038
6 6.81 0.2 663.0 364.0 2413
7 10.0 0.2 262.0 785.0 2057
8 21.5 0.2 399.0 3630.7 1449
9 21.5 4.0 833.0 175.26 1461
10 31.6 0.2 123.5 7843.4 969
11 31.6 4.0 295.0 385.9 1138
12 46.4 4.0 137.5 839.29 1154
13 68.1 4.0 735.0 1758.5 1292
14 68.2 14.0 275.0 498.55 1371
15 100.0 4.0 384.0 3921.22 1506
16 100.0 14.0 144.0 1100.45 1585
17 147.0 14.0 631.0 2403.5 1517
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Fig 2A: QHAK-Type Section
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Fig 2B: QHAK-Type Section
7. Molua O. Collins et al Adv. Appl. Sci. Res., 2013, 4(6):268-276
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VES 2 computation of thickness and apparent resistivity
CO-ORDINATES:
A = 0, hO) = (1700 ohm-m, 1.60m)
B = 1, h1) = (3100 ohm-m, 3.50m) h1/ho = 4.0
C. = 2, h2) = (2000 ohm-m, 5.40m) h2/h1 = 0.5
D. = 3, h3) = (1100 ohm-m, 27.5m) h3/h2 = 4.2
E. = 4 h4) = (1450, ohm-m, 110m) h4/h3 = 2.8
Table 3: Layer Parameters
Layer Thickness h(m) App. Resistivity a (ohm-m) How Computed
1 1.60 1700
2 6.40 3966
hoxh1/ho=1.60x4=6.4
ox 1/ o=1700x2.333=3966
h1
1
3 1.75 1329
h1xh2/h1=3.5x0.5=1.75
1x 2/ 1=3100x0.42825=1329
h2
2
4 22.68 1000
h2xh3/h2=5.4x4.2=22.68
2x 3/ 2=2000x0.5=1000
h3
3
5 77.0 1650
h3xh4/h3=27.5x2.8=77
3x 4/ 3=1100x1.50=1650
h4
4
6 967
h4xh5/h4=110x00= 0
4x 5/ =1450x0.667=967
h5
5
Total transverse Resistance (R) = Σ 1h1= 180, 158.150hm-m2
Total Longitudinal Conductance (S) = ∑ = 7.32x102
mho (Siemens)
Total Thickness (H) = Σh1= 109.48m.
Transverse Resistivity (Pt) = R/H = 1646.33 ohm-m
Longitudinal resistivity ( 11)= H/S = 1495.63 ohm-m
Resistivity of rocks and soils okwueze, 1978 as reported by Boyo, 1988 as reported by Otobo [4].
Table 4: Table of established resistivity ranges for the different rocks in Ugbowo area of Benin City
ROCK TYPE
RESISTIVITY RANGE
MINIMUM RESISITIVY VALUE (OHM-M) MAXIMUM RESISTIVITY VALUE (OHM-M)
Top Soil 160 1000
Laterite 300 5176
Clay 300 800
Sand clay/clay Sand 1000 1500
Clean Sand 1000 11000
Ves 1: Interpretation.
This sounding was conducted along 150o
Azimuthal (30o
SE) behind state school of Nursing, Sapele Road, Benin
City. The result of the sounding curve figure (4.5) show a 6-layer QHAK type geoelectric structure with a top layer
whose resistivity is 3,500 ohm-m, underlain by a lower resistivity layer of 1,500 ohm-m. The third and the fourth
layers have resistivities of 400 Ohm-m. The third and the fourth layers have resistivities of 400 ohm-m and 1517
ohm-m respectively while the fifth and the sixth layers have resistivities of 1600 ohm-m and 1000 ohm-m
respectively.
Correlating this result with that of the geoelectric resistivity as shown in figure 4.7 we observed that the first layer
which extends to a depth of 2.15m is composed of dry sand. The second layer with thickness 10.75m is made of
sand, while the third layer of thickness 2.33m is of clayey sand. The fourth layer of thickness 2.75m is made up of
sand. The fifth layer with thickness 108m units is composed of water bearing sand and very extensive. The sixth
layer is composed of water saturated sand. The water table was encountered here as inferred from borehole logs that
water level exists on an average of 70m below the surface while the maximum depth of penetration in this station is
8. Molua O. Collins et al Adv. Appl. Sci. Res., 2013, 4(6):268-276
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125.98m. The total tranverance resistance at this station is 201,553.75 ohm and the longitudinal conductance at this
station is 8.29 x 102
mho. The coefficient of anisotropy is: 1.026
Ves 2: Interpretation.
This was carried out on the same bearing i.e. parallel to the first but not having same centre point. This is separated
from the first at a distance of about 50m. Results of the sounding curve in figure (4.8) shows a six layer KHK type
geoelectric structure with the top layer whose resistivity is 1,700 ohm-m, underlain by a layer of higher resistivity of
3966 ohm-m. The third and the fourth have resistivities 1329 Ohm-m and 1000 ohm-m respectively, while the fifth
and the sixth layers have resistivities of 1650 ohm-m and 967 ohm-m respectively.
The first layer of thickness, 1.6m contains sand (top soil) while the second layer of thickness 6.4m contains Dry
Sand. The third layer having thickness of 1.75m still contains dry sand. The fourth of thickness 22.68m is composed
of sand. The fifth layer having thickness of 77.0 is composed of water bearing sand, while the sixth layer composed
of water saturated sand. Maximum depth penetration was 109.48m, and as in VES I the water table was
encountered. The total transverse resistance is 180,158.15 ohm while the longitudinal conductance at this station is
7.32x102 mho. The coefficient of anisotropy is: 1.05.
Results from the appropriate interpretation techniques
Table 5: VES 1 (summary)
LAYER
APPARENT RESISTIVITY
(Ohm-m)
THICKNESS h(m) LITHOLOGY
1
2
3
4
5
6
3,500
1500
400
1517
1600
1000
2.15
10.75
2.33
2.75
108
∞
Dry sand (Top Soil) sand
Clayery and
Sand
Water bearing sand and
very extensive
Table 6: VES 2 (summary)
LAYER
APPARENT RESISTIVITY
(Ohm-m)
THICKNESS h(m) LITHOLOGY
1
2
3
4
5
6
1700
3966
1329
1000
1650
967
1.60
6.4
1.75
22.68
77.0
∞
Sand (Top Soil)
Dry Sand
Dry Sand
Sand
Water bearing Sand
Water saturated sand.
Based on the interpretation of the VES curves, it was found that the water bearing formations (Aquifers) was mainly
sands. This was encountered in both VES I and VES 2 stations. For the case of VES I the depth to probable aquifers
was 17.98m while the water table is within the sixth layer with resistivity 1000 ohm-m considering the sixth later the
low resistivity of the layer as compared to the fifth can be associated to the water present in the sixth layer. The
second station VES I that was done in a saddle, where water was encountered again has the probable aquifers at
depth of 32.43m, while the water table is within the sixth layer with resistivity of 967 ohm-m. The low resistivity of
the sixth layer as compared to that the layer can be associated to the water present in the sixth layer.
CONCLUSION
The Benin formation as one can infer from the data acquired so far in the field survey, is mainly sand and at the
same time slightly isotropic. It was observed that the topography plays a major role in that if on a high level it takes
a very wide spread of the electrodes before a deeper penetration even up to the aquifer can be achieved, unlike when
it is done in a saddle like in the case of VES 2.
From the results got from the investigation of Sapele area using the resistivity method, to be more particular the use
of Schlumberger array shows that the depth of probable water bearing formation at a depth of 17.98m in the elevated
region tend at 32.43 in the saddle below ground surface. The survey area may hold good prospect for ground water
9. Molua O. Collins et al Adv. Appl. Sci. Res., 2013, 4(6):268-276
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in view of its fairly thick aquifer layer. And in most cases will not require going through great depth before hitting
water.
Acknowledgements
We wish to the contribution of late Mr Idovah B P. whose work formed the bedrock of this paper.
REFERENCES
[1] Asokhia, M. B. Engineering Geology Samtos Service Ltd Lagos Nigeria. 1995
[2]Beck, A .E. Physical principles of exploration method Mc Nigeria Association of petroleum of
Eplorationist.1981.
[3] Dauda, O.F. Application of Electrical Resistivity Method to hydro-geological problems of the Benin formation
(Unpublished B.Sc project, Geology department, Uniben). 1989
[4] Otobo,E. Determination of water bearing formation in Oko area of Benin-city by electrical resistivity method
(Unpublished M.Sc Thesis, physics department, Uniben ). 1992