electrical resistivity sounding for subsurface delineation and evaluation of groundwater potential...
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Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
Electrical Resistivity
Evaluation of Groundwater Potential of Araromi Akungba
Ondo State
Muraina Z. Mohammed1, 2, 3
Department of Geology & Applied Geophysics, Adekunle Ajasin University, Akungba Akoko
PMB 001, Akungba*E-mail of the correspondence author: [email protected]
Abstract
Electrical resistivity sounding of Araromi area of
subsurface units and evaluating the groundwater potential of the area. Forty (40) Schlumberger vertical electrical
resistivity soundings were acquired with ABEM SAS 1000 Resistivity Meter. The elec
varied from 1 – 65 m with maximum spread length
involved partial curve matching and computer iteration technique using WinResist software.
Three to four distinct subsurface geologic layers were identified from the geoelectric layers, aided by borehole
lithological logs. These included a lateritic clay/sandy clay/clayey sand/sandy topsoil, clayey weathered layer,
partially weathered/fractured basement and the fresh baseme
ohm-m and 0.7-1.5 m; 196-472 ohm
respectively.. The depth to bedrock varied from 0 to 20.1 m. The bedrock relief was generally uneven, with
bedrock elevations that varied between 312 and 346 m above sea level. The bedrock relief map delineated two
major parallel basement depressions striking approximately NW
The isopach map of the overburden show
constituted the dominant aquifer units with tendency for low groundwater potential
and thin nature of the overburden. Future groundwater resource developmen
feasible in few places characterized by relatively thick
Keywords: Schlumberger, Sounding, Electrode, Resistivity, Thickness, Groundwater, Rating
1. Introduction
The availability of safe and potable water in an environment is a veritable index of a tremendous role to the
development and growth of a community.
and students of Adekunle Ajasin University in Akungba t
towns of Iwaro- Oka and Etioro -
between Ikare and Owo towns in the northern part of Ondo state southwestern Nigeria.
Araromi-Akungba community has witnessed an exponential increase in population of various groups of
people in recent times. The inhabitants range from students to civil workers and artisans/local traders that
migrated to earn livings with the relocation of a state un
development heralded an increased local economy of the community as well as impacted heavy demands on
potable water for domestic uses. Inhabitants depend primarily on shallow water wells/hand
surface water resources which usually run dry during the dry season. During this period, limited amount of
potable water for consumption is usually sourced from water vendors and few boreholes sunk by the state
government and few individuals. These provisions
individuals and governmental agencies are not meeting expectations as two out of three boreholes sunk for water
supplies usually fail as soon as works are completed on them.
At present, groundwater via shallow hand dug wells and few borehole constructions constitutes a major
source of drinking water supply in this area. The yields are somewhat variable and less than expected average
considered enough for the overall populace. In order to ease the probl
living standard of the community this study was initiated to delineate the subsurface geological sequences and
their hydrogeological characteristics/groundwater potentials in the light of the notably sustainable groundw
yield of typical basement terrains. Generally, surface water accumulates after precipitation under the influence of
gravity in rock cavities as a vast groundwater reservoir supplying wells, boreholes, springs and flowing streams
(Harr 1962). In a typical Precambrian Basement Complex area
within the weathered and the tectonically induced geological features; fractured/fissured, sheared or jointed/faulted
basement columns of the rock unit(s). These
of burial and hence increase the porosity and permeability of such units for groundwater accumulation, discharge
0948 (Online)
29
al Resistivity Sounding for Subsurface Delineation and
Groundwater Potential of Araromi Akungba
Ondo State Southwestern Nigeria
Muraina Z. Mohammed1*
Thompson H. T. Ogunribido2 & Adedamola T. Funmilayo
Department of Geology & Applied Geophysics, Adekunle Ajasin University, Akungba Akoko
PMB 001, Akungba-Akoko, Ondo state. Nigeria.
mail of the correspondence author: [email protected]
sounding of Araromi area of Akungba Akoko was conducted with a view to de
units and evaluating the groundwater potential of the area. Forty (40) Schlumberger vertical electrical
resistivity soundings were acquired with ABEM SAS 1000 Resistivity Meter. The electrode spacing (AB/2) was
65 m with maximum spread length of 130 m. The interpretation of the data was quantitative, and
involved partial curve matching and computer iteration technique using WinResist software.
face geologic layers were identified from the geoelectric layers, aided by borehole
lithological logs. These included a lateritic clay/sandy clay/clayey sand/sandy topsoil, clayey weathered layer,
partially weathered/fractured basement and the fresh basement with resistivity and thickness values of 3
472 ohm-m and 3.9-20.1 m; 533-742 ohm-m and 1.8-4.2 m; and infinity ohm
. The depth to bedrock varied from 0 to 20.1 m. The bedrock relief was generally uneven, with
bedrock elevations that varied between 312 and 346 m above sea level. The bedrock relief map delineated two
major parallel basement depressions striking approximately NW-SE as the major groundwater collecting centers
The isopach map of the overburden showed generally thin overburden (< 15 m). The weathered/fractured layer
constituted the dominant aquifer units with tendency for low groundwater potential rating
and thin nature of the overburden. Future groundwater resource development in the study area is considered
feasible in few places characterized by relatively thick and sandy column of the overburden
Schlumberger, Sounding, Electrode, Resistivity, Thickness, Groundwater, Rating
of safe and potable water in an environment is a veritable index of a tremendous role to the
development and growth of a community. Araromi area of Akungba Akoko is a new settlement notably for staff
and students of Adekunle Ajasin University in Akungba town. It is bounded in the east and south by neighboring
Supare Akoko respectively, and it is situated southeast of Akungba town
between Ikare and Owo towns in the northern part of Ondo state southwestern Nigeria.
ungba community has witnessed an exponential increase in population of various groups of
people in recent times. The inhabitants range from students to civil workers and artisans/local traders that
migrated to earn livings with the relocation of a state university to Akungba Akoko few years ago. This
development heralded an increased local economy of the community as well as impacted heavy demands on
potable water for domestic uses. Inhabitants depend primarily on shallow water wells/hand
ace water resources which usually run dry during the dry season. During this period, limited amount of
potable water for consumption is usually sourced from water vendors and few boreholes sunk by the state
government and few individuals. These provisions are grossly inadequate as further efforts by group of
individuals and governmental agencies are not meeting expectations as two out of three boreholes sunk for water
supplies usually fail as soon as works are completed on them.
shallow hand dug wells and few borehole constructions constitutes a major
source of drinking water supply in this area. The yields are somewhat variable and less than expected average
populace. In order to ease the problem of water scarcity and improve the
living standard of the community this study was initiated to delineate the subsurface geological sequences and
their hydrogeological characteristics/groundwater potentials in the light of the notably sustainable groundw
yield of typical basement terrains. Generally, surface water accumulates after precipitation under the influence of
gravity in rock cavities as a vast groundwater reservoir supplying wells, boreholes, springs and flowing streams
cal Precambrian Basement Complex area, this groundwater reservoir is usually contained
within the weathered and the tectonically induced geological features; fractured/fissured, sheared or jointed/faulted
basement columns of the rock unit(s). These geological processes alter the rock units to reduce resistivity
and hence increase the porosity and permeability of such units for groundwater accumulation, discharge
www.iiste.org
Sounding for Subsurface Delineation and
Groundwater Potential of Araromi Akungba-Akoko
& Adedamola T. Funmilayo3
Department of Geology & Applied Geophysics, Adekunle Ajasin University, Akungba Akoko
mail of the correspondence author: [email protected]
Akungba Akoko was conducted with a view to delineating the
units and evaluating the groundwater potential of the area. Forty (40) Schlumberger vertical electrical
trode spacing (AB/2) was
130 m. The interpretation of the data was quantitative, and
involved partial curve matching and computer iteration technique using WinResist software.
face geologic layers were identified from the geoelectric layers, aided by borehole
lithological logs. These included a lateritic clay/sandy clay/clayey sand/sandy topsoil, clayey weathered layer,
nt with resistivity and thickness values of 3-174
4.2 m; and infinity ohm-m
. The depth to bedrock varied from 0 to 20.1 m. The bedrock relief was generally uneven, with
bedrock elevations that varied between 312 and 346 m above sea level. The bedrock relief map delineated two
as the major groundwater collecting centers.
The weathered/fractured layer
rating arising from the clayey
t in the study area is considered
overburden units.
Schlumberger, Sounding, Electrode, Resistivity, Thickness, Groundwater, Rating
of safe and potable water in an environment is a veritable index of a tremendous role to the
Araromi area of Akungba Akoko is a new settlement notably for staff
own. It is bounded in the east and south by neighboring
and it is situated southeast of Akungba town
ungba community has witnessed an exponential increase in population of various groups of
people in recent times. The inhabitants range from students to civil workers and artisans/local traders that
iversity to Akungba Akoko few years ago. This
development heralded an increased local economy of the community as well as impacted heavy demands on
potable water for domestic uses. Inhabitants depend primarily on shallow water wells/hand-dug wells and
ace water resources which usually run dry during the dry season. During this period, limited amount of
potable water for consumption is usually sourced from water vendors and few boreholes sunk by the state
are grossly inadequate as further efforts by group of
individuals and governmental agencies are not meeting expectations as two out of three boreholes sunk for water
shallow hand dug wells and few borehole constructions constitutes a major
source of drinking water supply in this area. The yields are somewhat variable and less than expected average
em of water scarcity and improve the
living standard of the community this study was initiated to delineate the subsurface geological sequences and
their hydrogeological characteristics/groundwater potentials in the light of the notably sustainable groundwater
yield of typical basement terrains. Generally, surface water accumulates after precipitation under the influence of
gravity in rock cavities as a vast groundwater reservoir supplying wells, boreholes, springs and flowing streams
groundwater reservoir is usually contained
within the weathered and the tectonically induced geological features; fractured/fissured, sheared or jointed/faulted
cal processes alter the rock units to reduce resistivity at depth
and hence increase the porosity and permeability of such units for groundwater accumulation, discharge
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
and exploitation. This, therefore, constitutes the basis of the choice of geo
this present study.
The method has been successfully employed in the delineation of subsurface geological sequence,
geological structures/features of interest, aquifer units, types and depth extent in almost all g
This is because of the significant resistivity contrasts that exist between different earth materials
Fasuyi 1993). The resistivity method can therefore map interface along which a resistivity contrast exists. This
interface may or may not coincide with geological boundary (Telford
survey / method works on the basis of energizing the subsurface via the use of two current electrodes with the
resulting potential difference measured by another two electrodes termed the potential electrodes.
2. Site Description
2.1 Site Location and Physiography
The study area is located in Araromi
confined within latitudes 70 27’ 5.82” and 7
approximate
Figure 1. Map of Ondo State showing the Study Area and the Layout
OSUN STATE
OGUN STATE
ATLANTIC OCEAN
4 30'E
6 00'N
6 30'
7 00'
7 30'N
4 30'E
Igbokoda/ Ilaje
Okitipupa
Odigbo/Ose
Ondo West
Ile-Oluji/Oke-Igbo
801200 801400 801600 801800
824600
824800
825000
825200
825400
825600
LEGEND
Major Roads
Building
Church
Minor Roads
From Akure
V.C. Lodge
Block Industry
Garage
Filling Station
To Supare Akoko
Outcrop
ATIARO QTRS
0948 (Online)
30
and exploitation. This, therefore, constitutes the basis of the choice of geoelectrical resistivity sounding survey in
The method has been successfully employed in the delineation of subsurface geological sequence,
geological structures/features of interest, aquifer units, types and depth extent in almost all g
This is because of the significant resistivity contrasts that exist between different earth materials
. The resistivity method can therefore map interface along which a resistivity contrast exists. This
ace may or may not coincide with geological boundary (Telford et al. 1990). The electrical resistivity
survey / method works on the basis of energizing the subsurface via the use of two current electrodes with the
resulting potential difference measured by another two electrodes termed the potential electrodes.
2.1 Site Location and Physiography
The study area is located in Araromi- Akungba-Akoko, Ondo State, Southwestern, Nigeria
27’ 5.82” and 70 27’ 41.63” and longitudes 5
0 43’ 41.43” and 5
Map of Ondo State showing the Study Area and the Layout
Abuja
DELTA STATE
KOGI STATE
EKITI STATE
5 00'E 5 30'E 6 00'E
5 00'E 5 30'E 6 00'E
LEGEND
State Boundary
Regional Boundary
SCALE - 1:400, 000
Igbokoda/
Ese Odo
Irele
Odigbo/Ose
Ondo West
Ondo East
Ile-Oluji/Oke-Igbo
Idanre
Ifedore Iju/Itaogbolu
AkureNorth
Owo
AkokoS/W
Isua Akoko
Ikare
Oka
AkokoN/W
Study Area
802000 802200 802400 802600
0m 500m
To AAUA Campus
To Iwaro-Oka
Block Industry
Garage
Filling Station
Outcrop
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electrical resistivity sounding survey in
The method has been successfully employed in the delineation of subsurface geological sequence,
geological structures/features of interest, aquifer units, types and depth extent in almost all geological terrains.
This is because of the significant resistivity contrasts that exist between different earth materials ( Olorunfemi &
. The resistivity method can therefore map interface along which a resistivity contrast exists. This
1990). The electrical resistivity
survey / method works on the basis of energizing the subsurface via the use of two current electrodes with the
resulting potential difference measured by another two electrodes termed the potential electrodes.
Akoko, Ondo State, Southwestern, Nigeria (Figure 1). It is
43’ 41.43” and 50 44’ 29.43” which
Map of Ondo State showing the Study Area and the Layout
Abuja
KOGI STATE
6 00'N
6 30'
7 00'
7 30'N
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
northings and eastings of 825739 mN and 802713 mN and 801047 mE and 824429 mE of the Universal
Traverse Mercator (UTM) Minna Zone 31 coordinates respectively. It covers an areal extent of about
The study area is characterized by relatively gentle undulating terrain with
Bordering the site in the far north and south ends are hil
the infrastructural development on the land expanse of the area. The hills trend between 090
mean annual rainfall is about 1300 mm and mean temperature of 27
characterized by wooden shrubs, palms, moist deciduous trees and herbaceous plants. The site is usually with
dense vegetation in the rainy season and sparse in the dry season. However, human interference has reduced the
vegetation. The area is generally drained by river Alatan.
2.2 Geology and Hydrogeology
The survey area is underlain by the Precambrian Basement Complex rock
rock exposures are however found
basement is shallow and erosional activities are active.
underlain by Migmatite - gneiss-quartzite Complex with the granite gneiss and grey
while the minor units include Mafic, granodiorite, pegmatite, garnet
area is sandwiched between two parallel prominent E
north and south ends. The features create a broad vall
typical basement complex area, groundwater is usually contained in the weathered col
sheared or jointed/faulted basement columns. These
hence increase the porosity and permeability of such unit
covered with variety of lateritic soil
Figure 2. Geological Map of Akungba
being a product of in situ weathered of the parent rocks. These weathered zones typically have been the source of
groundwater in hand dug wells. The static water level of wells and few bore
to 8.0 m.
LEGEND
Migmatite
Granite
Gneiss
Granite Gneiss
5 44'0
0948 (Online)
31
northings and eastings of 825739 mN and 802713 mN and 801047 mE and 824429 mE of the Universal
a Zone 31 coordinates respectively. It covers an areal extent of about
study area is characterized by relatively gentle undulating terrain with elevations of between 326 and 350 m
Bordering the site in the far north and south ends are hills and inselbergs. The features create a b
infrastructural development on the land expanse of the area. The hills trend between 090
mean annual rainfall is about 1300 mm and mean temperature of 270C (Duze & Ojo 19
characterized by wooden shrubs, palms, moist deciduous trees and herbaceous plants. The site is usually with
dense vegetation in the rainy season and sparse in the dry season. However, human interference has reduced the
s generally drained by river Alatan.
The survey area is underlain by the Precambrian Basement Complex rock of southwestern Nigeria
however found as lowland outcrop in few places within the survey area
basement is shallow and erosional activities are active. However, according to Rahaman (1976 &
quartzite Complex with the granite gneiss and grey gneiss being the major units
while the minor units include Mafic, granodiorite, pegmatite, garnet-sillimanite gneiss and quartzite (Fig
area is sandwiched between two parallel prominent E-W ridges/inselbergs of granite gneiss composition
The features create a broad valley for groundwater resource development
typical basement complex area, groundwater is usually contained in the weathered column and fractured/
basement columns. These geological processes alter rock units to reduce resistivity and
and permeability of such units for groundwater accumulation. The study
covered with variety of lateritic soil
Geological Map of Akungba-Akoko (modified after Farotimi, 2002).
in situ weathered of the parent rocks. These weathered zones typically have been the source of
The static water level of wells and few boreholes in the area range between 1.5
Migmatite
Granite
Gneiss
Granite Gneiss
Major Roads
Minor Roads
Geological (Rock)
Boundary
5 45' E0
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northings and eastings of 825739 mN and 802713 mN and 801047 mE and 824429 mE of the Universal
a Zone 31 coordinates respectively. It covers an areal extent of about 1.5 km sq.
elevations of between 326 and 350 m.
ls and inselbergs. The features create a broad valley for
infrastructural development on the land expanse of the area. The hills trend between 0900 and 125
0. The
1982). The vegetation is
characterized by wooden shrubs, palms, moist deciduous trees and herbaceous plants. The site is usually with
dense vegetation in the rainy season and sparse in the dry season. However, human interference has reduced the
of southwestern Nigeria. The basement
in few places within the survey area particularly where
according to Rahaman (1976 & 1988 a), the area is
gneiss being the major units
sillimanite gneiss and quartzite (Figure 2). The
W ridges/inselbergs of granite gneiss composition found at the
development. Generally, in a
umn and fractured/fissured,
geological processes alter rock units to reduce resistivity and
s for groundwater accumulation. The study area is
Akoko (modified after Farotimi, 2002).
in situ weathered of the parent rocks. These weathered zones typically have been the source of
holes in the area range between 1.5
7 28'N0
5 45' E
7 27'0
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
3. Methods of Study
3.1 Field Survey/Data Acquisition Technique
Forty (40) Schlumberger vertical electrical resistivity soundings were acquired at selected stations not more than
75 m station – station interval particularly along and/ or few meters away from major / minor roads / footpaths
and built – ups (Figure 3). The electrode spacing (AB/2) was varied from 1
of 130 m. The ABEM SAS 1000 Resistivity Meter was used for the m
ground apparent resistivity measured is a function of electrode spacing, geometry of electrode array, subsurface
layer thickness, angle of dip and anisotropic properties (Ako, 1979). The product of the measured grou
resistance (R) value and the geometric factor (G) of the electrode array for each set up gave the ground apparent
resistivity values.
Figure 3
3.2 Data Processing/Analysis
The data obtained from each station
curve for subsequent interpretation by manual partial curve matching. The partial curve matching technique
involved the matching of successive segments of the field curve by a set of
curves (Orellana and Mooney, 1966) and the corresponding auxiliary curves.
from the partial curve matching were
Velpen, 1988). The interpretation
computer-graphic display system (Ghosh, 1974; Sharma, 2000). The system made use of a fast computer to
calculate an apparent resistivity curve for a given layer
the partial curve matching interpretation was obtained
less than 10 % .
V19
V20
V21
V22
V23
V24
801200 801400
824600
824800
825000
825200
825400
825600
LEGEND
Major Roads
VES Stations
Building
Church
Minor Roads
From Akure
V.C. Lodge
To Supare Akoko
G
I
0948 (Online)
32
3.1 Field Survey/Data Acquisition Technique
Forty (40) Schlumberger vertical electrical resistivity soundings were acquired at selected stations not more than
al particularly along and/ or few meters away from major / minor roads / footpaths
ups (Figure 3). The electrode spacing (AB/2) was varied from 1 – 65 m with maximum spread length
of 130 m. The ABEM SAS 1000 Resistivity Meter was used for the measurement of the ground resistance. The
ground apparent resistivity measured is a function of electrode spacing, geometry of electrode array, subsurface
layer thickness, angle of dip and anisotropic properties (Ako, 1979). The product of the measured grou
resistance (R) value and the geometric factor (G) of the electrode array for each set up gave the ground apparent
Figure 3. Data Acquisition Map of the Study Area.
The data obtained from each station were plotted on transparent bi-logarithms graph paper to obtain a smooth
curve for subsequent interpretation by manual partial curve matching. The partial curve matching technique
involved the matching of successive segments of the field curve by a set of two-layer theoretical Schlumberger
curves (Orellana and Mooney, 1966) and the corresponding auxiliary curves. The geoelectric parameters obtained
from the partial curve matching were refined by computer iteration technique using WinRESIST software (
ion by forward and inverse modeling techniques was an interactive
graphic display system (Ghosh, 1974; Sharma, 2000). The system made use of a fast computer to
calculate an apparent resistivity curve for a given layer sequence. From the above, the refinement of the results of
the partial curve matching interpretation was obtained and found satisfactory with the root square mean (rsm) of
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V25
V26
V27 V28
V29
V30
V31
V32
V33
V36
V37
V38
V39
V40
801600 801800 802000 802200 802400
Major Roads
VES Stations
Minor Roads
0m
To AAUA Campus
Block Industry
Garage
Filling Station
Outcrop
ATIARO QTRS
A
C
D
E
F
H
J
K
L
M
Study Area
www.iiste.org
Forty (40) Schlumberger vertical electrical resistivity soundings were acquired at selected stations not more than
al particularly along and/ or few meters away from major / minor roads / footpaths
65 m with maximum spread length
easurement of the ground resistance. The
ground apparent resistivity measured is a function of electrode spacing, geometry of electrode array, subsurface
layer thickness, angle of dip and anisotropic properties (Ako, 1979). The product of the measured ground
resistance (R) value and the geometric factor (G) of the electrode array for each set up gave the ground apparent
logarithms graph paper to obtain a smooth
curve for subsequent interpretation by manual partial curve matching. The partial curve matching technique
layer theoretical Schlumberger
The geoelectric parameters obtained
computer iteration technique using WinRESIST software (Vander
by forward and inverse modeling techniques was an interactive
graphic display system (Ghosh, 1974; Sharma, 2000). The system made use of a fast computer to
the refinement of the results of
and found satisfactory with the root square mean (rsm) of
V33V34
V35V36
802400 802600
500m
To Iwaro-Oka
B
M
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
4. Results and Discussion
4.1 Results Presentation
The results of the data obtained from the field are presented as tables, depth sounding curves, geo
sections and maps. However, the qualitative interpretation applied to the quantitative interpretation results of the
depth sounding curves enabled the classifi
simple two electrical layers to four layer
4.2 Field Curves and Geoelectric Sections
The field curves obtained within the stu
A-type being the dominant. The typical VES c
Seven geoelectric sections were drawn in the NW
The sections generally delineate three to
topsoil, the weathered layer, fractured basement and the fresh bedrock (Fig
first layer ranges from 38 - 3533 Ωm with thickness of 0
and laterites. The resistivity of the underlying
that vary between 0 and 8.5 m. It is composed of clay, sandy clay and sand. The weathered layer is underlain by
the fractured basement in few places. The resistivity of the fractured zones varies between 432 and 90
the thickness ranges from 4.2-10.7 m. The basal unit is the fresh bedrock with resistivity that varies from 1050 to
infinity ohm-m and the depth to the bedrock ranges from 0 to 14.1 m.
overburden is generally thin. The overburden/weathered basement is absent in places particularly beneath VES
station 39 and beneath VES stations 16, 25, 26 and 28 where basement rock outcropped/thin overburden
respectively. The generally thin nature of the overburden of less tha
hydrogeologically appeal except where exist a significantly saturated thickness column of greater than 10 m in
the area.
.
0948 (Online)
33
of the data obtained from the field are presented as tables, depth sounding curves, geo
sections and maps. However, the qualitative interpretation applied to the quantitative interpretation results of the
depth sounding curves enabled the classification of the VES data into curve types. The classification ranged from
simple two electrical layers to four layered curves arising from the layer resistivity combinations.
4.2 Field Curves and Geoelectric Sections
The field curves obtained within the study area are the H (6), A (16), HA (8), AA (1) and KH (7) types with the
. The typical VES curve types are shown in Figures 4 (a & b).
Seven geoelectric sections were drawn in the NW-SE and approximately SW-NE directions within the study area.
three to four major geoelectric/subsurface geologic layers which include; the
red basement and the fresh bedrock (Figures 5 a – g).
3533 Ωm with thickness of 0 - 3.7 m. The topsoil is composed of clay, sandy clay
underlying weathered layer ranges from 32 - 632 Ωm with thickness values
that vary between 0 and 8.5 m. It is composed of clay, sandy clay and sand. The weathered layer is underlain by
places. The resistivity of the fractured zones varies between 432 and 90
10.7 m. The basal unit is the fresh bedrock with resistivity that varies from 1050 to
and the depth to the bedrock ranges from 0 to 14.1 m. The geoelectric sections show that the
thin. The overburden/weathered basement is absent in places particularly beneath VES
station 39 and beneath VES stations 16, 25, 26 and 28 where basement rock outcropped/thin overburden
generally thin nature of the overburden of less than 10 m in most places make the area less
ally appeal except where exist a significantly saturated thickness column of greater than 10 m in
Figure 4 a: Typical HA Curve Type.
Figure 4 b: Typical KH Curve Type.
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of the data obtained from the field are presented as tables, depth sounding curves, geo-electric
sections and maps. However, the qualitative interpretation applied to the quantitative interpretation results of the
cation of the VES data into curve types. The classification ranged from
arising from the layer resistivity combinations.
dy area are the H (6), A (16), HA (8), AA (1) and KH (7) types with the
4 (a & b).
NE directions within the study area.
layers which include; the
g). The resistivity of the
3.7 m. The topsoil is composed of clay, sandy clay
632 Ωm with thickness values
that vary between 0 and 8.5 m. It is composed of clay, sandy clay and sand. The weathered layer is underlain by
places. The resistivity of the fractured zones varies between 432 and 907 Ωm and
10.7 m. The basal unit is the fresh bedrock with resistivity that varies from 1050 to
The geoelectric sections show that the
thin. The overburden/weathered basement is absent in places particularly beneath VES
station 39 and beneath VES stations 16, 25, 26 and 28 where basement rock outcropped/thin overburden
n 10 m in most places make the area less
ally appeal except where exist a significantly saturated thickness column of greater than 10 m in
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
Figure 5 a: A NW-SE Geoelectric Section obtained along Line A
Figure 5 b: A NW-SE Geoelectric Section obtained along Line C
Figure 5 c: A NW-SE Geoelectric Section obtained along Line E
Figure 5 d: A NW-SE Geoelectric Section obtained along Line G
Figure 5 e: A SW-NE Geoelectric Section obtained along Line I
Figure 5 f: A SW-NE Geoelectric Section obtained along Line J
20
15
10
5
0
De
pth
(m
)
V30 V39
LEGEND
A
38
133
30
20
10
0
Depth
(m
)
V18
124101
432
6488
C
20
15
10
5
0
Depth
(m
)
V16
11010419
E
20
15
10
5
0
Depth
(m
)
V21 V24
93
375
2677
124
352
G
30
20
10
0
Depth
(m
)
V22
98
383
I
20
15
10
5
0
Dep
th (
m)
V26 V29
2875487
237
298
5787
J
0948 (Online)
34
SE Geoelectric Section obtained along Line A-B (Resistivity values in
SE Geoelectric Section obtained along Line C-D (Resistivity values in
SE Geoelectric Section obtained along Line E-F (Resistivity values in
SE Geoelectric Section obtained along Line G-H (Resistivity values in
NE Geoelectric Section obtained along Line I-C (Resistivity values in
NE Geoelectric Section obtained along Line J-K (Resistivity values in
V31 V32 V33 V34
LEGEND
91
159
163 63220
271
127
213730
254
V17 V14 V12
222
205
91
70
696
33598
182
59
527
V15 V13
123207
86
302
51
942
V25 V26 V28
1294869
2875487 1224
8257
V21 V20 V19
93
375
2677
79270
67
95
1413
V4 V3 V1
125
57
2294
312479
75
13115
252
1528
www.iiste.org
B (Resistivity values in Ωm).
D (Resistivity values in Ωm).
ues in Ωm)
H (Resistivity values in Ωm)
C (Resistivity values in Ωm).
K (Resistivity values in Ωm)
V35 B
430
32
V11
219413
94
4145
D
V3
312479
75
13115
F
V28 V8
322
1224
8257
626
487
10347
H
V18
124101
432
6488
C
V1 V31
106
252
1528
91
159
K
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
Figure 5 g: A SW-NE Geoelectric Section obtained along Line L
4.3 Geo-electrical Maps
The isoresistivity map of the topsoil in Araro
shows the variation in the resistivity of the topsoil within the study area. The topsoil resistivity varies from 38 to
greater than 1000 ohm-m typical of hard
ohm-m) at VES 23 stations and 39 nearest to an outcrop. The resistivity is moderately high (between 300 and
1000 ohm-m) in the eastern part of the area particularly at the extreme north
of the topsoil is generally low with resistivity
northeastern portions of the area. The
within the study area. It shows that the
that the topsoil in the area rarely goes beyond 1 m thickness except in the western portion and in the extreme
north (beneath VES station 30), including
This thin nature of the topsoil is a reflection of basement highs in most places thus hinders hand
hydrogeologically unappealed.
The isoresistivity map of the weathered layer is shown in Figure
resistivity of the weathered layer within the study area. The
ohm-m. The region which shows resistivity values greater than 700 ohm
VES station 39) and southwest (beneath VES
the fresh basement. The resistivity of the w
the central portion of the study area
southern portions of the area. The low resistivity may be indicative of a clayey
resistivity may be indicative of a sandy
of the weathered layer within the study area. The
the weathered layer is generally thin
stations 23 and 39. Nevertheless, it shows pockets of f
VES stations 3, 8, 38, etc.
The distribution of the overburden thickness within the
Appreciable overburden thickness zones are possible groundwater collecting zones. Hence, unconsolidated
materials could contain reliable aquifer if thick and sandy. (Satpathy and Kanungo, 1976; Olorunfemi and
Olorunniwo, 1985; Dan Hassan and Olorunfemi, 1999;
Ojo et al., 2007). Also related geophysical studies in a typical basement terrain identified thick overburden as
zone of high groundwater potential (Olorunfemi and Okhue, 1992; Bala and Ike, 2001; Mohamm
The map shows overburden thickness with values that vary from 0
observed throughout the study area with overburden that is very thin and rarely greater than 10 m in most places.
The overburden is relatively fair in thickness (10
vicinity of VES stations 14, 18 and 37. These zones are suggestive of possible groundwater potential zones in the
area.
Figure 6 f shows the variation in the bed
have identified hydrogeological significance of bedrock depressions (
and Okhue, 1992; Dan Hassan and Olorunfemi, 1999; Bala and Ike, 2001
Akintorinwa, 2007; Omosuyi., 2010
overburden. Conversely,
20
15
10
5
0D
ep
th (
m)
V28 V7 V6
322
1224
8257
725
257 907
LEGEND
L
0948 (Online)
35
NE Geoelectric Section obtained along Line L-M (Resistivity values in
The isoresistivity map of the topsoil in Araromi area of Akungba-Akoko is shown in (Figure
shows the variation in the resistivity of the topsoil within the study area. The topsoil resistivity varies from 38 to
m typical of hard-pan laterite and/or bedrock. The resistivity is generally high (>1000
m) at VES 23 stations and 39 nearest to an outcrop. The resistivity is moderately high (between 300 and
m) in the eastern part of the area particularly at the extreme north-east and south
f the topsoil is generally low with resistivity that is less than 300 ohm-m in the western, central and
The map in Figure (6 b) shows the variation in the thickness of the topsoil
within the study area. It shows that the thickness of the topsoil varies from 0 to 3.8 m. This generally indicates
that the topsoil in the area rarely goes beyond 1 m thickness except in the western portion and in the extreme
30), including VES stations 2 and 9 where the thickness values go beyond 1.6 m.
This thin nature of the topsoil is a reflection of basement highs in most places thus hinders hand
The isoresistivity map of the weathered layer is shown in Figure 6 c. The map shows the distribution in the
d layer within the study area. The resistivity varies from 32 to greater than 1000
m. The region which shows resistivity values greater than 700 ohm-m is observed in the north (beneath
39) and southwest (beneath VES station 23). No weathered layer was encountered in these areas but
the fresh basement. The resistivity of the weathered layer is generally less than 200 ohm-
ral portion of the study area while the resistivity is moderately high (200-700 ohm
of the area. The low resistivity may be indicative of a clayey matrix while the moderately high
of a sandy nature of the column. Figure 6 d shows the distribution in the thickness
layer within the study area. The thickness varies from 0 to 8.5 m. The isopach map shows that
the weathered layer is generally thin and averagely (< 4 m) and absent in some places especially b
stations 23 and 39. Nevertheless, it shows pockets of fairly thick weathered layer (> 7 m)
The distribution of the overburden thickness within the study area is generally shown in
reciable overburden thickness zones are possible groundwater collecting zones. Hence, unconsolidated
materials could contain reliable aquifer if thick and sandy. (Satpathy and Kanungo, 1976; Olorunfemi and
Olorunniwo, 1985; Dan Hassan and Olorunfemi, 1999; Bala and Ike, 2001; Mohammed and Olorunfemi,
). Also related geophysical studies in a typical basement terrain identified thick overburden as
zone of high groundwater potential (Olorunfemi and Okhue, 1992; Bala and Ike, 2001; Mohamm
shows overburden thickness with values that vary from 0 - 14.1 m. A relatively uniform thickness is
observed throughout the study area with overburden that is very thin and rarely greater than 10 m in most places.
s relatively fair in thickness (10-14 m) in the northwestern and southeastern portions in the
vicinity of VES stations 14, 18 and 37. These zones are suggestive of possible groundwater potential zones in the
shows the variation in the bedrock topography of the study area. Previous geoelec
hydrogeological significance of bedrock depressions (Satpathy & Kanungo,
and Okhue, 1992; Dan Hassan and Olorunfemi, 1999; Bala and Ike, 2001; Mohammed, 2007
2010) as groundwater collecting centers and are usually characterized by thick
V6 V9
179134
907
352116
2980
Fractured Basement
0100m
10m
LEGEND
Topsoil
Weathered Layer
Fresh Basement
www.iiste.org
M (Resistivity values in Ωm).
Akoko is shown in (Figure 6 a). The map
shows the variation in the resistivity of the topsoil within the study area. The topsoil resistivity varies from 38 to
tivity is generally high (>1000
m) at VES 23 stations and 39 nearest to an outcrop. The resistivity is moderately high (between 300 and
east and south-east. The resistivity
the western, central and
shows the variation in the thickness of the topsoil
thickness of the topsoil varies from 0 to 3.8 m. This generally indicates
that the topsoil in the area rarely goes beyond 1 m thickness except in the western portion and in the extreme
e thickness values go beyond 1.6 m.
This thin nature of the topsoil is a reflection of basement highs in most places thus hinders hand-dug wells and
map shows the distribution in the
resistivity varies from 32 to greater than 1000
m is observed in the north (beneath
23). No weathered layer was encountered in these areas but
-m and it is observed in
700 ohm-m) in the north and
while the moderately high
shows the distribution in the thickness
thickness varies from 0 to 8.5 m. The isopach map shows that
absent in some places especially beneath VES
airly thick weathered layer (> 7 m) especially beneath
study area is generally shown in (Figure 6 e).
reciable overburden thickness zones are possible groundwater collecting zones. Hence, unconsolidated
materials could contain reliable aquifer if thick and sandy. (Satpathy and Kanungo, 1976; Olorunfemi and
Bala and Ike, 2001; Mohammed and Olorunfemi, 2007;
). Also related geophysical studies in a typical basement terrain identified thick overburden as
zone of high groundwater potential (Olorunfemi and Okhue, 1992; Bala and Ike, 2001; Mohammed et al., 2012).
14.1 m. A relatively uniform thickness is
observed throughout the study area with overburden that is very thin and rarely greater than 10 m in most places.
14 m) in the northwestern and southeastern portions in the
vicinity of VES stations 14, 18 and 37. These zones are suggestive of possible groundwater potential zones in the
rock topography of the study area. Previous geoelectrical studies
Satpathy & Kanungo, 1976,.Olorunfemi
Mohammed, 2007; Oladapo and
) as groundwater collecting centers and are usually characterized by thick
V36
206127
1702
M
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
(a)
(b)
Figure 6. (a) Isoresis
V19
V20
V21
V22
V23
V24
801200 801400
824600
824800
825000
825200
825400
825600
From Akure
V.C. Lodge
To Supare Akoko
V19
V20
V21
V22
V23
V24
801200 801400
824600
824800
825000
825200
825400
825600
LEGEND
Major Roads
VES Stations
Building
Church
Minor Roads
From Akure
V.C. Lodge
To Supare Akoko
0948 (Online)
36
(a) Isoresistivity Map, (b) Isopach Map of the Topsoil of the Study Area
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V25
V26
V27 V28
V29
V30
V31
V32
V37
V38
V39
V40
801600 801800 802000 802200 802400
To AAUA Campus
ATIARO QTRS
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V25
V26
V27 V28
V29
V30
V31
V32
V37
V38
V39
V40
801600 801800 802000 802200 802400
Major Roads
VES Stations
Minor Roads
0m
To AAUA Campus
Block Industry
Garage
Filling Station
Outcrop
ATIARO QTRS
Study Area
www.iiste.org
of the Topsoil of the Study Area
V33V34
V35V36
802400 802600
To Iwaro-Oka
V33V34
V35V36
802400 802600
500m
To Iwaro-Oka
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
(c)
(d)
Figure 6. (c) Isoresistivity Map
V19
V20
V21
V22
V23
V24
801200 801400
824600
824800
825000
825200
825400
825600
From Akure
V.C. Lodge
To Supare Akoko
V19
V20
V21
V22
V23
V24
801200 801400
824600
824800
825000
825200
825400
825600
LEGEND
Major Roads
VES Stations
Building
Church
Minor Roads
From Akure
V.C. Lodge
To Supare Akoko
0948 (Online)
37
Isoresistivity Map, (d) Isopach Map of the Weathered Layer of the Study Area
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V25
V26
V27 V28
V29
V30
V31
V32
V33
V36
V37
V38
V39
V40
801600 801800 802000 802200 802400
To AAUA Campus
ATIARO QTRS
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V25
V26
V27 V28
V29
V30
V31
V32
V33
V36
V37
V38
V39
V40
801600 801800 802000 802200 802400
Major Roads
VES Stations
Minor Roads
0m
To AAUA Campus
Block Industry
Garage
Filling Station
Outcrop
ATIARO QTRS
Study Area
www.iiste.org
of the Weathered Layer of the Study Area
V33V34
V35V36
802400 802600
To Iwaro-Oka
V33V34
V35V36
802400 802600
500m
To Iwaro-Oka
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
(e)
(f)
Figure 6. (e) Overburden Thickness Map, (f) Bedrock Relief Map of the Study Area
V18
V19
V20
V21
V22
V23
V24
V25
801200 801400
824600
824800
825000
825200
825400
825600
From Akure
V.C. Lodge
To Supare Akoko
ATIARO QTRS
V18
V19
V20
V21
V22
V23
V24
V25
801200 801400
824600
824800
825000
825200
825400
825600
LEGEND
Major Roads
VES Stations
Building
Church
Minor Roads
From Akure
V.C. Lodge
To Supare Akoko
ATIARO QTRS
0948 (Online)
38
(e) Overburden Thickness Map, (f) Bedrock Relief Map of the Study Area
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V25
V26
V27 V28
V29
V30
V31
V32
V33V34
V36
V37
V38
V39
V40
801600 801800 802000 802200 802400
To AAUA Campus
ATIARO QTRS
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
V11
V12
V13
V14
V15
V16
V17
V18
V25
V26
V27 V28
V29
V30
V31
V32
V33V34
V36
V37
V38
V39
V40
801600 801800 802000 802200 802400
0m
To AAUA Campus
Block Industry
Garage
Filling Station
Outcrop
ATIARO QTRS
Study Area
www.iiste.org
(e) Overburden Thickness Map, (f) Bedrock Relief Map of the Study Area
V34
V35
802600
To Iwaro-Oka
V34
V35
802600
500m
To Iwaro-Oka
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
ridges are usually associated with
characteristic features are observed in (Figure
depression. The depression found sandwiched betwe
approximately NW-SE direction of the study area
serves as groundwater collecting centre in this area and is suggestive of a major NW
in-filled with weathering products. This
5. Conclusions
Three to four geoelectric layers were delineated within the study area. These include; the topsoil, the weathered
layer, partially weathered/fractured basement and the
that its composition varies from clay to laterite. Maps generated using the obtained geoelectrical parameters
revealed the variation of the different layer resistivity and thicknesses within the
there exists a variable potential for groundwater development in the area
thickness of saprolite/weathered/fractured columns within a short distance.
weathered/fractured column is generally thin across the area except for the fairly thick columns as pockets of
sandy materials found scattered the
weathered/fractured layer constituted the dominant aquifer units wit
rating arising from the clayey and thin nature of the overburden. Future groundwater resource development in
the study area is considered feasible in few places characterized by relatively thick and sandy column of
overburden units. Hence, the groundwater potential of the study area
very best.
References
Ako, B. D. (1979). Geophysical prospecting for groundwater in parts of Southwestern
Ph.D Thesis. O.A.U, Ife. Pp. 70
Bala, A. E. and Ike, E. C. (2001
North-Western Nigeria”. Journal of Mining and Geology
Dan Hassan, M. A. and Olorunfemi, M.
North central part of Kaduna State, Nigeria. Journal of Mining and Geology, Vol. 35 (2), pp. 189
Duze, M. and Ojo, A. (1982). Senior School Atlas Macmillan. Pp. 113.
Farotimi, A. (2002). Geological Map of Akungba
Ghosh, D. P. (1971). The application of linear filter theory to the direct interpretation of
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Keller, G. V., and Frischknecht, F. C.,
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Mohammed, M. Z., (2007). Hydrogeophysical Investigation of parts of the River Jama are Floodplain, West
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Mohammed, M. Z. and Olorunfemi, M. O., (2007)
Transition Zone of parts of River Jama’are Flodplain in the West Chad
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Mohammed, M. Z., Olorunfemi, M. O. and Idornigie, A. I. (2012)
corrosivity and the vulnerability of porous media aquifers in parts of the Chad Basin F
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doi:10.5539/jsd.v5n7p111
Ojo, J. S., Olorunfemi, M. O. & Omosuyi, G.
the Coastal Plain Sands of Okitipupa
Oladapo, M. I. and Akintorinwa, O.
Global J. Pure and Applied Sci. 13(1): 55
Oladapo, M. I., Mohammed, M. Z. Adeoye, O.
Ondo State Housing Corporation Estate, Ijapo, Akure, Southwestern, Nigeria. Journal of Mining and
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part of the central basement terrain of
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Borehole Sitting”. Journal of Mining and Geology, pp 403
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39
associated with thin overburden cover and are groundwater diverting centers.
characteristic features are observed in (Figure 6 f). The zone with a relatively low relief
found sandwiched between two highs/bedrock ridges run
SE direction of the study area where contours are closed. Hence, the lone major depression
serves as groundwater collecting centre in this area and is suggestive of a major NW-SE suspected regional fault
filled with weathering products. This result correlates with that obtained from the overburden thickness map
Three to four geoelectric layers were delineated within the study area. These include; the topsoil, the weathered
layer, partially weathered/fractured basement and the fresh basement rock. The resistivity of the topsoil reveals
that its composition varies from clay to laterite. Maps generated using the obtained geoelectrical parameters
revealed the variation of the different layer resistivity and thicknesses within the area. The study revealed
l for groundwater development in the area. This is because of the variable
thickness of saprolite/weathered/fractured columns within a short distance. The weath
d column is generally thin across the area except for the fairly thick columns as pockets of
sandy materials found scattered the study area particularly towards the northwestern part
weathered/fractured layer constituted the dominant aquifer units with tendency for low groundwater potential
rating arising from the clayey and thin nature of the overburden. Future groundwater resource development in
the study area is considered feasible in few places characterized by relatively thick and sandy column of
roundwater potential of the study area is generally of a low
Geophysical prospecting for groundwater in parts of Southwestern
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2001). “The Aquifer of the Crystalline Basement Rocks in Gusau Area,
Journal of Mining and Geology. 37(2): 177 – 184.
A. and Olorunfemi, M. O. (1999). Hydrogeophysical Investigation of a Basement Terrain in the
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. Senior School Atlas Macmillan. Pp. 113.
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The application of linear filter theory to the direct interpretation of geoelectric
resistivity soundings measurements. Geophysical Prospecting. Vol. 19, No. 2, Pp. 192
ischknecht, F. C., (1966). Electrical Methods in Geophysical Prospecting, Oxford:
Hydrogeophysical Investigation of parts of the River Jama are Floodplain, West
Chad Basin, Northeastern Nigeria. Unpubl. Ph.D Thesis Obafemi Awolowo Univ.
Mohammed, M. Z. and Olorunfemi, M. O., (2007). Geoelectric Investigation of the Sedimentary/Basement
Transition Zone of parts of River Jama’are Flodplain in the West Chad Basin, Northeastern Nigeria.
Journal of Science Research Annals. Vol.3 No.2, pp. 44-59.
Mohammed, M. Z., Olorunfemi, M. O. and Idornigie, A. I. (2012). Geoelectric sounding for evaluating soil
corrosivity and the vulnerability of porous media aquifers in parts of the Chad Basin F
Journal of S. Dev., Vol. 5, No. 7; Canadian Center of Sc.& Ed.,
Omosuyi, G. O. (2007). Geoelectric Sounding to Delineate Shallow Aquifers in
lain Sands of Okitipupa Area S.W. Nigeria. Online J. of Earth Sciences, vol. 1(4), pp. 170
I. and Akintorinwa, O. J. (2007). Hydrogeophysical Study of Ogbese, Southwestern, Nigeria.
Global J. Pure and Applied Sci. 13(1): 55-61.
Z. Adeoye, O. O. and Adetola, B. A. (2004). Geoelectrical Investigation of the
Ondo State Housing Corporation Estate, Ijapo, Akure, Southwestern, Nigeria. Journal of Mining and
Geology, Vol 40(1), pp. 41-48.
, S. A. (1993). Aquifer types and the geoelectric/hydrogeologic characteristics of
part of the central basement terrain of Nigeria (Niger State). Jour. of African Earth Sciences. 16,
Olorunfemi, M. O., (1992). “Geoelectric Investigation in Okene and its Implication for
Borehole Sitting”. Journal of Mining and Geology, pp 403-411.
www.iiste.org
water diverting centers. These two
with a relatively low relief is indicative of a
runs parallel and trends
. Hence, the lone major depression
SE suspected regional fault
result correlates with that obtained from the overburden thickness map.
Three to four geoelectric layers were delineated within the study area. These include; the topsoil, the weathered
fresh basement rock. The resistivity of the topsoil reveals
that its composition varies from clay to laterite. Maps generated using the obtained geoelectrical parameters
area. The study revealed that
. This is because of the variable
he weathered/ partially
d column is generally thin across the area except for the fairly thick columns as pockets of
area particularly towards the northwestern part. The
h tendency for low groundwater potential
rating arising from the clayey and thin nature of the overburden. Future groundwater resource development in
the study area is considered feasible in few places characterized by relatively thick and sandy column of the
s generally of a low level rating, at the
Geophysical prospecting for groundwater in parts of Southwestern Nigeria. Unpublished
. “The Aquifer of the Crystalline Basement Rocks in Gusau Area,
Hydrogeophysical Investigation of a Basement Terrain in the
North central part of Kaduna State, Nigeria. Journal of Mining and Geology, Vol. 35 (2), pp. 189-206.
geoelectric
19, No. 2, Pp. 192-217.
. Electrical Methods in Geophysical Prospecting, Oxford:
Hydrogeophysical Investigation of parts of the River Jama are Floodplain, West
mi Awolowo Univ., Ile – Ife. Nigeria. Pp.
Geoelectric Investigation of the Sedimentary/Basement
Basin, Northeastern Nigeria. In
Geoelectric sounding for evaluating soil
corrosivity and the vulnerability of porous media aquifers in parts of the Chad Basin Fadama Floodplain,
Journal of S. Dev., Vol. 5, No. 7; Canadian Center of Sc.& Ed.,
Geoelectric Sounding to Delineate Shallow Aquifers in
of Earth Sciences, vol. 1(4), pp. 170 – 179.
. Hydrogeophysical Study of Ogbese, Southwestern, Nigeria.
. Geoelectrical Investigation of the
Ondo State Housing Corporation Estate, Ijapo, Akure, Southwestern, Nigeria. Journal of Mining and
Aquifer types and the geoelectric/hydrogeologic characteristics of
of African Earth Sciences. 16,
Investigation in Okene and its Implication for
Journal of Environment and Earth Science
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)Vol 2, No.7, 2012
Olorunfemi, M. O. and Okhue, E. T.
at Ile-Ife, Nigeria. Journal of Mining
Olorunfemi, M. O. and Olorunniwo, M.
parts of Southwestern, Nigeria. Geologic Applicate E. Hydrogeological XX, Part 1, pp. 99
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Adekunle Ajasin University, Akungba Akoko
available in the Department of Geology/Applied Geophysics
reviewers is also acknowledged.
Muraina Z. Mohammed born in Ogbagi Akoko Ondo state, southwestern Nigeria.
He received a B. Tech. (1992) and an M. Tech. (1997) Degrees in Applied/Exploration Geophysics from the
Federal University of Technology, Akure and a Ph.D (2007) Degree in Applied Geophysics from O
Awolowo Univesity, Ile – Ife, Nigeria. His major field of study is Exploration and
His other interests are in Applied /Exploration Geophysics
Hydrocarbon Exploration and GPR studies of active faults.
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RESIST Software Version 1.0. M. Sc Research Project. ITC, Delft, Netherlands.
Copyright © 2004, ITC, IT-RSG/DSG.
Adekunle Ajasin University, Akungba Akoko is gratefully acknowledged for the use of her
in the Department of Geology/Applied Geophysics. The encouraging comment from the anonymous
born in Ogbagi Akoko Ondo state, southwestern Nigeria.
He received a B. Tech. (1992) and an M. Tech. (1997) Degrees in Applied/Exploration Geophysics from the
Federal University of Technology, Akure and a Ph.D (2007) Degree in Applied Geophysics from O
Ife, Nigeria. His major field of study is Exploration and Environmental
in Applied /Exploration Geophysics; Control Source Electromagnetic (
and GPR studies of active faults.
www.iiste.org
. Hydrogeological and Geologic Significance of a Geoelectric Survey
229.
. Geoelectric Parameters and Aquifer Characteristics of some
parts of Southwestern, Nigeria. Geologic Applicate E. Hydrogeological XX, Part 1, pp. 99-109.
. “Hydrogeophysical Evaluation of the Groundwater
Journal of Mining and Geology. 35(2):207 –
Groundwater Prospect and vulnerability of overburden
Layer Master Curve for Vertical Electrical Sounding over
. “Review of the Basement Geology of Southwestern Nigeria”. In: Geology of Nigeria.
. Recent advances in the study of the basement complex of Nigeria. In: P. O. Oluyide
ordinator), Precambrian Geology of Nigeria. Geol. Surv. Nigeria. Publ., p. 11-43.
Cambridge University Press.
ater Exploration in Hard Rock, A Case Study; Geoph.
t. ITC, Delft, Netherlands.
use of her field facilities
encouraging comment from the anonymous
He received a B. Tech. (1992) and an M. Tech. (1997) Degrees in Applied/Exploration Geophysics from the
Federal University of Technology, Akure and a Ph.D (2007) Degree in Applied Geophysics from Obafemi
Environmental Geophysics.
Control Source Electromagnetic (CSEM) for
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