Groundwater is characterized by a certain
number of parameters, which geophysical methods try to
determine from surface measurement mostly indirectly, but
sometimes directly. Groundwater is a primary input for
the sustainable development of an area. It plays a protective
role against the vagaries monsoon. The surface resistivity
sounding is very much effective in estimating aquifer thickness
and basement topography which help in identifying various
suitable sites for groundwater exploration. On the basis
of prevailing hydrogeological conditions, subsurface lithology
and the result of geophysical investigation in various
locations for construction of borewell, dugcum-borewell,
etc., a subsurface geoelectrical survey, using Vertical
Electrical Sounding (VES) method and borehole logs, was
carried out around Malanpur area of Bhind district in order
to investigate the aquifer characteristics and thickness
and assess their groundwater potential in the study area.
Nine Vertical Electrical Sounding (VES) were conducted
within the area and its environment using the Schlumberger
array configuration for identifying the horizontal and
vertical variation in subsurface lithology and depth of
rock. The data were interpreted using curve matching method
(Orellana and Mooney, 1966). The geoelectrical data of
layers and parameters have been correlated with the lithology
borehole drill in the study area. The result reveals that
four layers belong to H, A, and K type curves. The aquifers
thickness varies between 3.0 m and 42.0 m; the resistivity
of the topsoil 5.5 to 260 Wm; pebble and kankar mixed
layers varies between 1.7 and 32.50 Wm. Aquifer resistivity
ranges from 10.5 to 280 Wm.
The aquifer characteristics and their
thickness are important properties for both groundwater
and land assessment purposes. The unconfined aquifer system
permits time-varying continuous decrease in water table
for the end of monsoon, even without withdrawal from the
aquifer. For optimal development and utilization of the
available groundwater source, detailed information regarding
basement topography, aquifer characteristics and depth
of rock are essential. Surface geophysical methods may
provide only rapid and effective technique for groundwater
exploration and aquifer delineation. Application of geophysical
methods is also very effective for water content estimation,
water quality assessment and mapping of the depth of the
water table and bedrock (Hubbard and Rubin, 2002). Singh
(2005) used the non-linear estimation of the aquifer parameters
from surfacial resistivity measurements. Venkateswara and
Briz Kishore (1991) used a method for the interpretation
of geophysical data and estimation of groundwater potential
index (GWPI) at various sites. Edet and Okereke (1997)
and Shahid and Nath (2005) used similar techniques
of GIS integration of Remote Sensing and Electrical Sounding
data for hydrogeological exploration. Ekwe and Onvoha (2006)
used the hydraulic parameters for the aquifer from electrical
sounding data of the middle Imo River Basin, Nigeria. Shadid et
al. (1999) used the Vertical Electrical Sounding (VES)
data and interpreted by using Evolutionary Programming
(EP) techniques based on global optimization. Geophysical
method is used for the investigation of subsurface geology,
e.g., lithological characters and thickness which play
a significant role in solving the hydrological problems
(Kelley, 1876 and 1961; Flathe, 1955; Zohddy, 1965; Brace,
1977; Keller and Frischknecht, 1979; Urish, 1981; Billa et
al., 1983; Bussain, 1983; and Kumar et al.,
2005). Prabhakara Rao and Negi (2003) used a similar approach
for the geoelectrical study of potable aquifers in parts
of Agra (UP). Ravikumar et al. (2007) studied
geophysical profiling by grid method, adopting the data
from VES. Kumar et al. (2005) studied the hydrogeophysical
properties and Digital Basement Topographic Model (DBTM).
DBTM helps in estimating the groundwater reserve beyond
the replenished reserve by estimating the entire volume
of aquifer above the basement surface. The present study
is aimed at the delineation of aquifer and their depth
and thickness, using the Electrical Resistivity method.
Nine Vertical Electrical Sounding (VES) were acquired at
various sites within the study area (Figure 1). The Schlumberger
method was adopted. The study area is situated in Bhind
district of Madhya Pradesh, India, bounded by latitudes
78° 15' to 78° 20' E and latitudes 26° 15'
to 26° 25' N, the covered in the survey of the Indian
toposheet No. 54 J/7. It covers an area of about 151.89
sq. km. The area is well-connected by broad gauge railway
line and lies on New Delhi-Chennai main railway line.
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