Exploration and evaluation of potential groundwater aquifers and subsurface structures at Beni Suef area in southern Egypt

Accepted Manuscript Exploration and evaluation of potential groundwater aquifers and subsurface structures at Beni Suef area in southern Egypt Taha Rabeh, Kamal Ali, Said Bedair, Mervat A. Sadik, Ahmed Ismail PII:

S1464-343X(18)30366-2

DOI:

https://doi.org/10.1016/j.jafrearsci.2018.11.025

Reference:

AES 3380

To appear in:

Journal of African Earth Sciences

Received Date: 9 July 2018 Revised Date:

23 November 2018

Accepted Date: 26 November 2018

Please cite this article as: Rabeh, T., Ali, K., Bedair, S., Sadik, M.A., Ismail, A., Exploration and evaluation of potential groundwater aquifers and subsurface structures at Beni Suef area in southern Egypt, Journal of African Earth Sciences (2018), doi: https://doi.org/10.1016/j.jafrearsci.2018.11.025. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Exploration and evaluation of potential groundwater aquifers and subsurface structures at Beni Suef Area in Southern Egypt Taha Rabeh Kamal Ali

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National Research Institute of Astronomy and Geophysics, Helwan, Cairo, Egypt Research Institute for Groundwater, National Water Research Center, Egypt

Said Bedair

Research Institute for Groundwater, National Water Research Center, Egypt

Mervat A. Sadik

October high Institute for engineering & technology, Egypt

Ahmed Ismail*

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Boone Pickens School of Geology, Oklahoma State University, Stillwater, Ok, USA

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Abstract

In recent years, the rapidly growing population of Egypt has increasingly stressed water resources necessitating concentrated and systematic efforts to find alternative water resources to meet the increased water demand. This study aims to assess and evaluate hydrological setting of Beni Suef, Egypt using geophysical survey and geochemical analysis

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an: integrated approach. We conducted a land magnetic survey to map the subsurface structures down to the basement, followed by a geoelectric resistivity survey to locate potential groundwater aquifers. Well logs from 10 wells were used to constrain the interpretations of the acquired data. Geochemical analyses of 10 water samples collected

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from available water wells was conducted to evaluate groundwater quality for agriculture and drinking purposes. The results of the magnetic and geoelectric surveys enabled imaging of the geological setting, the dominant structures and a potential groundwater aquifer in the

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area. The results indicated that the main aquifer is a shaly-limestone layer located at depths ranging from 20 to 150 m below ground surface. The data detected a series of normal faults that most likely represent subvertical conduits responsible for recharging the delineated aquifer. The outlined aquifer thickness as well as sources of groundwater recharge indicate that this aquifer may not provide sustainable supply for agricultural development purposes. Furthermore, the groundwater quality test indicated that certain treatments are necessary to make this water safe for drinking. Keywords: magnetic, geoelectric, well logs, chemical analyses, groundwater aquifers.

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1. Introduction Egypt’s rapidly growing population of over 100 million are living along the valley

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and delta of the River Nile, which constitute only ~5% of the 1 million-km2 area of Egypt (UNDP, 2016). To cope with the rapid increase in population, the Egyptian government has implemented a national plan for groundwater exploration in the vast desert of Egypt outside the fringes of the Nile Valley and Delta. This plan aims to locate areas of potential

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groundwater resources and evaluate the quality and quantity of groundwater at the new areas in order to estimate water sustainability for agriculture and development in these areas. One of the promising areas for this national plan is the desert on both sides of the Nile Valley in

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the Beni Suef area in southern Egypt (Fig. 1). The area belongs to the unstable shelf, which is characterized by thick marine and terrestrial sediments (Said, 1990). As exploring groundwater resources in the Beni Suef area has gained a national interest, the complex subsurface structure in this area often presented a challenge for proper mapping and characterization of existing groundwater aquifers.

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Using geophysical methods for groundwater exploration in areas of complex structures has developed significantly during the past few decades with the advance in geophysical imaging techniques (Ismail et al., 2005; Metwaly et al., 2009). These geophysical methods including magnetic and gravity are able to image the subsurface

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geological structures over large areas (Rabeh et al., 2017). Once the structural setting of an area is mapped using gravity or magnetic techniques, exploring groundwater potential

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within the mapped structure can be easily achieved using electrical or electromagnetic techniques. The groundwater quality can also be assessed based on a set of geochemical analyses of 10 water samples collected from exiting water wells in the area (Olusola et al., 2018).

The subsurface structure of the study area was outlined based on few regional

geological and geophysical studies that were conducted in southern Egypt (Said, 1990). However, to our knowledge, none of these studies has focused on the area of study and mapped the detailed structures. The groundwater exploration efforts in the area were limited 1

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to the information gathered from domestic water wells. The quality of the groundwater in this area has gained more attention and a number of published studies have elaborated on the groundwater quality and stability for domestic uses (Melegy et al, 2013 and Khalaf and Gad, 2014). Most of these studies reached a common conclusion about the quality of the

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surface and groundwater in the Beni Suef area being contaminated from unsupervised anthropogenic activities.

As exploring groundwater resources in the Beni Suef area has gained a national interest, it is necessary to improve our understanding of the structural groundwater aquifers

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and groundwater quantity and quality in the area. We designed an integrated geophysical, geochemical and well logging investigation to assess the geological setting and evaluate the

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groundwater resources quality and quantity in the area. The geophysical investigation included a detailed land magnetic survey using a proton magnetometer in a mesh-like network followed by a geoelectric resistivity survey in the form of vertical electrical soundings (VES) techniques. The well logs from the 20 drilled shallow wells within the area were analysed to aid the interpretation of the acquired geophysical data. We also collected water samples from 10 available water wells in the area and analyzed them to assess the

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water suitability for both agriculture and other domestic uses.

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Figure 1. Location map of the Beni Suef area in southern Egypt showing the different surface geology units (modified after Said, 1981). 2. The Study Area The Beni Suef study area lies between latitudes 28° 42′ & 29° 18′ N and longitudes 30°40′ & 31°20′ E, with a total area of about 1680 km2 (Fig. 1). The climate of the study area is arid to semi-arid with hot dry summers and moderate winters with little or no

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rainfall. According to the climate data center of Egypt, the annual precipitation in the region of the study area is about 7 mm and the average temperature is 21.4 ℃. Because of the

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climate conditions, the evaporation rates from the limited surface water resources in the area including the Nile River and Lake Yousef are relatively high (Abdel Wahed, 2015).

The geomorphology in the Beni Suef area exhibits rugged topography ranging from

limestone hills to relatively flat land formed of wind-blown sands changing to agriculture land towards the Nile Valley (Fig. 1). According to Said (1962, 1971, and 1981), the subsurface stratigraphy in the area comprising the Beni Suef basin is filled with sedimentary succession and contains a number of old rock units including, from bottom to top, the Bahariya Formation of Early Cenomanian, the Abu Roash Formation of Late Cenomanian3

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Turonian-Santonian and the Khoman Formation of Campanian–Maastrichtian. This stratigraphic succession rests conformably on the top of the Albian Kharita Member, which is the latest stage of the Lower Cretaceous. The Albian Kharita Member rests unconformably on the surface of the basement rocks. The top contact of the examined

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Upper Cretaceous succession unconformably underlies the Lower-Middle Eocene Apollonia Formation, which forms the exposed rolling land-surface in the area of study (Fig. 2).

The Aptian/Albian NE-SW extension movement controls the Beni Suef basin. This

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movement resulted in the removal of the pre-Albian succession, where the Kharita Formation (Albian) was deposited directly on the basement. A number of faults that can be

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characterized into two main sets including NE faults and NW faults dissected the area (Zahran et al., 2011). Based on the drilled wells along both sides of the River Nile, the Research Institute of Groundwater (RIGW, 1991) constructed a geologic cross-section along profiles S-S' in figure (1) showing geology, hydrogeology and structure of the shallow

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subsurface (Fig. 3).

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Figure 2. A generalized lithostratigraphic succession of the East of Nile valley, Beni Suef basin (EON), which includes the examined Upper Cretaceous succession (modified after Schlumberger, 1984).

Figure 3. Geohydrological cross section constructed based on water well information showing the main groundwater aquifers in the study area (after RIGW, 1991). 5

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3. Material and methods 3.1. Acquisition and processing of the magnetic data The proton magnetometer of geometrics type (G-856) was used in the current study

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to acquire an extensive land magnetic survey in a form of a mesh-like network. One proton magnetometer was kept fixed at a quiet magnetic area, designated as a base station, while the second proton magnetometer was mobile, and utilized to measure the magnetic field intensity along the pre-designed mesh-like network over the area. The data acquisition was performed for the observed stations along the study area. The distance between the

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measured stations ranged between 500 meters to 1 km according to the magnetic field variations and field conditions. The accurate geographical locations of the measured stations

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were identified using a global positioning system instrument (GPS) with an accuracy of about 1 m. The magnetic vector’s declination and inclination angles have caused a small shift between mapped locations of the magnetic anomalies caused by subsurface sources and its true locations (Mendonca and Silva,1993). Thus, we applied the reduction-to-the-pole (RTP) technique developed by Mendonca and Silva (1993) to the total magnetic intensity

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map to produce RTP magnetic map (Fig. 4).

Figure 4. RTP land magnetic map for the study area showing the measured magnetic 6

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stations. As a first analysis step to the RTP map, the horizontal gradient analysis was tested on the RTP land magnetic map in order to delineate trends of subsurface faults according to

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the theory of Grant and West (1965) and the technique of Linsser (1967). Plotting the peaks of the gradient curve along all the profiles over the RTP map and connecting them together helped in manifesting the structure lines. The different directions of the subsurface fault structures were then divided into azimuth sectors of 10° each. The azimuth sectors are designed in accordance with the directions of the tectonic movements that prevailed in the

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studied area.

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The Werner Deconvolution method developed by Werner (1953) was designed to analyze the potential field data resulting from arbitrary sources. Signal simplifications is one of the limitations of this method, however, it is still capable of providing a wide range of applications. Therefore, we applied the full derivation interpretation method to the magnetic data using the technique developed by Cerovsky and Pasteka (2003). The method works by analyzing the data for n-point operator length, which means solving (n) equations for either

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(n) or fewer number of unknowns. The clustering algorithm was applied to the Werner Deconvolution data. These clusters were manifested by removing the noise interference to produce solutions that are more robust. The deduced clusters show the geometry of the basement surface, which allows us to conclude the subsurface structures.

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Algorithms were developed during the early 1960s (e.g. Bott, 1963; Talwani, 1960, Bhattacharyya, 1980) to deal with polyhedrals of a very general shape. Shuey and Pasqual

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(1973) have developed a 2.5-dimension algorithm that applies the end corrections to the infinite extent model. Grant and West (1965) developed a relationship between the magnetic field (A) caused by a volume (v) of magnetized rock with a dipole moment per unit volume (M) and measured at an external point (r). This relationship is described in equation (1). A(r) =

--------------------------------------------------------- (1)

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Where:

is a volume integration over the entire body, r is the space within the xz plane

and r0 is the distance between the location of a point in the magnetic field A and the center of the magnetic body.

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The 3D version of this equation was also developed by the same author and indicated by equation (2). U = 1/2

--------------------------------------------------- (2)

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where U is the Newtonian potential.

According to the theories of Grant and West (1965) and Talwani (1960), the

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technique of 3-D modeling was applied to the magnetic data according to Encom ModelVision Pro (2004) software. We applied the technique to a set of selected profiles along the RTP magnetic map of the study area as shown in figure (6a). The 3D inversion model gives the advantage of characterizing the layered structures and isolated bodies such as dykes and/or any form of igneous intrusions. The layers of magnetic susceptibility may vary in both vertical and horizontal sense. The RTP magnetic data were digitized along

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selected profiles using automatic digitizing software. The digitized data were used to calculate the potential field of each causative body after adjusting some parameters such as

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the lateral extent, magnetic susceptibility, inclination, declination, and XZ coordinates.

3.2. Acquisition of well logging data and processing The well logging data were recorded by the Center of Water Researches between

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1999 and 2001. The logged wells were drilled mainly for defining the geologic setting, the distribution and extent of groundwater aquifers, and recording the water levels in the study area. The wells drilled into the sedimentary rock cover and reached maximum depths on the order of 350 m. In order to construct the subsurface geologic setting and the structures of the area, we relied on integrated information about the geology of the area and the analysis of the well logs, which were mainly gamma ray logs. Correlating a series of gamma ray logs can outline the subsurface geology of area as gamma ray logs are typically used to discern different geologic units based on their lithologic composition (Stohr et al., 2004). The 8

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availability of the lithologic description of the drilled wells was useful in constraining the gamma logs correlation and interpretation. We correlated the gamma ray logs along two linear cross-sections (G1 – G1` and G2 – G2`), the locations of their baseline is displayed in

3.3. Acquisition and processing of the geoelectric data

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(Fig. 4).

The geoelectrical data acquired from the study are in the form of vertical electrical soundings (VES) data acquired using a Syscal Junior R72 (IRIS) instrument. The

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Schlumberger electrode array was implemented to acquire 28 VES along selected profiles in the study area (Fig. 5). During the VES survey, transmitting direct current (DC) between a

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pair of electrodes generates a potential difference that can be measured by another pair of electrodes. The farther the distance between the current electrodes, the deeper the current can penetrate resulting in a greater depth of imaging (Dahlin, 2001). The current electrode spacings are increased to a maximum of 200 m. An apparent resistivity curve is produced from plotting the measured resistivity in the field against the current electrode spacings

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(AB/2).

Zohdy and Bisdorf (1989) computer program was used to analyze the acquired VES data. The program uses field-measured data sets of apparent resistivity and electrode spacing to generate a true 1D resistivity model of true resistivity versus true depth. This model

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inverts every single resistivity measurement into a single resistivity layer, which does not make geological sense. The results obtained from Zohdy and Bisdorf (1989) program were

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used to build up a starting model to be further interpreted by the automated inversion technique modified by Sauck (1990). In this interpretation procedure, a linear filter theory has been coupled with the Marquardt method to automatically interpret the resistivity sounding data. The matching between the field and model data is measured by the sum of squares of logarithms of the field and model data. The output interpreted results include layers thicknesses and resistivities (Fig. 6).

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Figure 5. A map showing locations of acquired VES data in the study area.

Figure 6. An example of VES data analysis using Zohdy and Bisdorf (1989) and Sauck (1990) inversion software methods applied to VES Station No. 8 to determine layers’ thicknesses and resistivities. . 3.4 Geochemical analysis The chemical analysis of 10 water samples collected from the water wells in the study area was conducted by the Egyptian National Research Center's laboratories (Olusola et al., 10

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2018) during the year 2017. The analysis aimed at investigating the water elements and evaluating the water quality. The concentration of the hydrogen ion (pH) in the water samples was measured. The pH is the negative value of the base 10 logarithm of the hydrogen ion concentration in the fluid. A pH value of 7 indicates neutral water, alkaline

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water has a pH value greater than 7, and acid water has a pH value of less than 7. The chemical analysis determined the concentrations of major anions and cations in the collected 10 water samples including Lead (Pb), Nitrate (NO3), Iron (Fe), Sulfates (SO4), Chloride (CL), Calcium (Ca) and Magnesium (Mg). Together the pH value and the measured

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concentrations of the main elements in the water samples will be used to determine the suitability of the groundwater of the aquifers for anthropogenic purposes according to the

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World Health Organization (WHO) standards.

4. Results

4.1. Magnetic data The results of the analyzed magnetic data show that the most predominant tectonic START HERE trends in the study area are oriented at 35º N - 45º E direction (related to the

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Syrian Arc tectonics) and N45°W (aligned with the Red Sea tectonics). Other spatially varying minor tectonic trends were also observed. These minor trends are most likely caused by regional tectonic effects. These fault structures are prevailing in the basement rocks and differ from the mapped fault structures at the surface as most of the later faults are trending

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NW-SE. This might be because this tectonic trend is still active. The results derived by the application of Werner Deconvolution method (Figs. 7a, and b) indicate that the mean depth

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to the basement rocks is ranging between 2 and 5 km. It’s notable that the effect of the imaged fault structures on the basement rock shows genuine correlation with the predicted faults along the cross-section generated from correlating the wells and well logs.

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Figure 7. a) magnetic data after the application of the Werner deconvolution method along G1-G1' magnetic profile and b) application of the Werner deconvolution method along G2G2' magnetic profile.

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The magnetic data interpretations were used to construct 2D profiles (Figs. 8a and b). These magnetic profiles show the general structures in the study area including dip, faults and stratigraphic features down to the basement rocks. The Werner solutions are clustering around the fault structure whereas the dotted blue lines connected between the Werner solutions are showing the geometry of the basement surface and hence the depths to the basement rocks.

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4.2 Well logging

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Figure 8. 3D magnetic modeling along the magnetic profiles G1 – G1' and G2 – G2'.

The gamma logs correlation aided by the lithologic description of the wells was used

to generate the geological cross-section, G1-G1` and G2- G2` in figure (9a and b). The base line of these two cross-sections is shown in figure (4). The G1-G1` cross-section connects three wells (S.Well, Soumosta Well-2, and W2-Well, Fig. 9a). The generated cross-section is limited to the depths of the wells, which ranges from 350 to 440 m along the cross-section G1-G1`. Five geological units are depicted by this cross-section including from top to bottom, sand & shale, sand, shale, shaly limestone and limestone units. The fault structure depicted along the G1-G1`cross-section are delineated based on the magnetic data. The G213

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G2` cross-section also connects three wells (QW, Q2 and Q3) and shows almost similar geological units as in the G1-G1` cross-section but with significantly different thickness and

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lateral distribution.

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Figure 9. 2D geologic cross-section constructed based on the interpretation of the well logging from the wells along the magnetic profile G1 – G1' (a) and G2 – G2' (b) in figure (5). 4.3. Geoelectrical data

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Five lithological units/layers have been identified along the geoelectric profiles shown in Figure 5. Thicknesses and lateral distributions of these geolectric layers are described along each geoelectric profile including:

Profile A–A′: This profile is crossing the Nile River extending NE to SW direction

(Fig. 10a) showing that the main aquifer is represented by an intermediate layer (Shaly limestone). This aquifer layer demonstrates the lowest resistivity values along the profile, with resistivity ranges from 75 ohm-m at the northeastern part (near the Nile River) to about 150 ohm-m southwest of the studied area. The aquifer is surrounding by saturated Shale 14

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rocks which represent a rechargeable factor for digitizing the fresh water from the Nile River through the fault structures symbolized by F1, F2 and F4. It appears that these structures have deeper origin reaching the basement rocks and are affecting the interpreted geoelectric layers. This is indicated by anomalously high resistivity (> 350 ohm-m) local

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feature that was interpreted as compacted limestone layer. The depth to this layer was confirmed by the drilled Well-1. These results were confirmed by the data from Well-1, WM and S. W-1.

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Profile B–B′: A close inspection of this profile indicates that it includes three geoelectric layers that have local effect on the aquifer layer (Fig. 10b). It can be noticed that

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the aquifer layer is surrounded by the Shale rock layer that represents the main source of recharge from the Nile River and the main cause of lowering the measured resistivity within the aquifer layer. These results were confirmed by the data from drilled Well (W6).

Profile D–D′: A close inspection of this profile (Fig. 10) indicates that it is affected by two faults of deep sources labeled as F1 and F2. The two faults form a horst limestone

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structure indicated by extremely higher resistivity values compared to the resistivity of the surrounding rock units along the entire length of the profile. This result agrees with results deduced by Abdel Wahed et al., (2007) from their study by using GPR data analyses. Mohamed et al., (2014) have made seismic study along the study area for oil exploration

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target. They stated that; the trap formed by faults owing to an extensional regime formed horst and graben structure. The results also show also the detected aquifer layer along the

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profile is absent under the geoelectric station VES 20. A possible interpretation of this sudden change could be lateral lithofacies change at this location especially with the surface topography is obviously low at this location indicating different depositional environments.

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Figure 10. Geoelectric profiles illustrating the rock succession and the electric resistivity values along three profiles A–A′, B–B′ and D–D′ with their locations shown in figure (5),

4.4. Geochemical analysis The results of the chemical analyses of the water samples are listed in Table (1). The measured concentrations of the major anions and cations show that the concentrations of the Pb, Cl, Fe, NO3, SO4, exceed the standard values published by the WHO. The relatively high 16

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concentration of the Cl in most of the water samples is likely caused by water contamination from sewage. The water quality indicators pH parameter, which is used to indicate the presence of harmful contaminants in water, was analyzed for all the water samples. The pH values were found to be relatively high, exceeding the WHO standards for drinking water

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(WHO, 1971). It is also worth notable that the increase in both Fe and Mg concentrations in the water samples was always associated with higher concentration of the Cl and SO4 (Table 1). The NO3 concentrations in the water samples was also found to be relatively high (Table 1).

pH

Lead (Pb) WHO 0.1mg/l

Nitrate (NO3) WHO 50mg/l)

Iron (Fe) WHO 0.3mg/l

Sulfates (SO4) WHO 250mg/l

7.4 7.35 7.7 7.4 7.8 7.1 7.15 7.17 7.7 7.5

0.06 0.07 0.05 0.08 0.06 0.04 0.03 0.03 0.08 0.07

80 85 77 69 61 60 55 60 70 72

0.58 0.51 0.53 0.4 0.52 0.44 0.5 0.48 0.40 0.55

291 287 271 299 265 270 280 275 260 264

QW Q2 S. Well S.Well -1 Q3 W2 W3 W4 W5 W6

Chlorides (CL) WHO 250mg/l

Calciu m (Ca) WHO 75mg/l

Magnesiu m Mg WHO 50mg/l

350 355 348 340 330 320 350 330 325 335

150 148 151 143 115 120 140 130 110 112

77 69 72 75 55 75 72 77 58 51

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WHO 6.5 to 8.5

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Well name

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Table 1: results of chemical analysis for the water samples collected from the drilled wells.

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5. Discussion and Conclusions

The study area, which is located south of Cairo comprises parts of the Nile Valley

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and the Eastern and Western Deserts of Egypt. The area lacks a detailed study concentrated on understanding its complex structural setting and evaluating its groundwater resources. As the study area is part of the unstable Shelf of Egypt, marine deposits have covered it predominantly. Therefore, the geologic section of the area shows thick units of deep marine deposits. The basement rocks are as deep as 5 km depth below ground surface at parts of the study area.

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We conducted this multidisciplinary study to evaluate the structural setting and the groundwater water aquifers as well as understanding the potential impact of the subsurface structures in the area on the groundwater aquifers, i.e. are the structures controlling the water supply and the recharge of these aquifers or otherwise? To meet the study objectives, an

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integrated magnetic and geoelectric surveys were conducted in the area and the interpretation was aided and constrained by well log information from the available 10 wells in the area. The well logs also helped in determining the geologic framework and detected small-scale variations in the sediments as well as indicating the depth to the groundwater

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aquifer.

The geoelectric survey determined the main aquifer layer in the area to be a shaly-

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limestone layer and traced its lateral and vertical distribution. The magnetic survey helped to estimate the depth to the basement rocks and delineated the subsurface structures in the study area in general and at the zone of the potential groundwater aquifer in particular. The magnetic results indicated that two predominant sets of fault systems oriented NE-SW and NW-SE affected the basement rocks. Meanwhile, the correlation of the locations of these faults and the zones of the groundwater accumulation shows that these faults are most likely

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responsible for conducting/transmitting groundwater to the aquifer. A saturated shale layer was mapped overlying the main groundwater aquifer. This layer was previously thought to be the source of aquifer recharge; however, the assumption may not be quite correct as the shaly layer is characterized by very low permeability. Shales can be fractured and though

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ductivity overall, they allow water to move through the cracksrelatively low in hydraulic con

We rather suggest, based on the results of our study, that the aquifer recharge takes

place mainly through the mapped faults that allows the water to move from the saturated shale layer to the main Shaly Limestone aquifer. The lateral movement of water from an adjacent saturated rock along the fault structures could be source of recharging the shalylimestone main aquifer. The conducted chemical analyses on 10 water samples collected from the main groundwater aquifer in the area showed slightly elevated pH values as well as relatively high 18

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concentrations of Pb, Cl, Fe, NO3, SO4, which exceed the WHO standards for drinking water. The results suggest possible sewage contamination to the groundwater aquifers. The water might be safe for agricultural purposes but treatment is necessary to make it safe for drinking. The results do not recommend the area for large-scale agriculture projects, as the

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aquifer-recharging rate is limited and the delineated aquifer may not provide sustainable water resources for agriculture.

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6. Acknowledgment

We would like to extend our sincere gratitude to the National Research Institute of Astronomy and Geophysics (NRIAG) and the Water Research Center (WRC) for providing

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the equipment to acquire the data and make the resources available to analyze acquired data and interpret the results.

7. References

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ACCEPTED MANUSCRIPT Research Highlights Magnetic survey for delineating complex subsurface structures in the study area. Geolectric resistivity survey for mapping groundwater acquirers in the study area. Integrating results to assess the aquifer sustainability for agriculture purposes.

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Geochemical analysis of groundwater samples to evaluate water quality for drinking.