2D Electrical Resistivity Imaging for Delineation of Crystalline Basement Aquifer in Northern Ghana

Abstract

Lack of access to potable and adequate water is a major problem for sustainable development in northern Ghana. Developing groundwater resource is the best option for safe, reliable, and cost-efficient water supplies to these dispersed communities. In this study, nine 2D ERI profiles were carried out with the Schlumberger array in eight communities underlain by the crystalline basement rocks in the Bole District of the Savannah Region of Ghana. The aim was to delineate the aquifer zones and select points for groundwater extraction. Nine boreholes were drilled from the selected points. The yield was found to vary from 12 to 180 l/min with a depth range of 50 to 70 m. The weathered and fractured zones together with the bedrock topography were clearly marked. It is evident that the 2D electrical resistivity technique is useful tool in determining the availability of groundwater in weathered and fractured crystalline environment.

Using electrical resistivity imaging technique for borehole calibration in selected communities in Asutifi North District, Ghana

“…This is because the occurrence and movement of groundwater in the rock types of this formation are largely controlled by secondary pores (Yeleliere, 2018). Also, according to Aning et al (2019), the secondary pore spaces within this geologic formation differ from one place to another at varying depths; hence, the aquifers are more discontinuous and localized. Therefore, the main challenge in developing groundwater resources in areas underlained by such geologic formations is identifying the appropriate locations for the drilling of productive boreholes.…”

“…The unpredictability of rainfall and the high cost of treating surface water sources make development of groundwater resources the most viable option for the attainment of the Sustainable Development Goal (SDG) 6.1, particularly, in the study area. *Corresponding author: dogolijames407@gmail.com However, the availability of groundwater in any area depends largely on the recharge and hydrogeological conditions of the area (Aning et al, 2019). In Ghana, groundwater in economic quantities within crystalline basement formation, underlying the area, is mostly associated with the presence of joints, fractures, and weathered zones (Issah, 2015;Aning et al, 2019).…”

“…*Corresponding author: dogolijames407@gmail.com However, the availability of groundwater in any area depends largely on the recharge and hydrogeological conditions of the area (Aning et al, 2019). In Ghana, groundwater in economic quantities within crystalline basement formation, underlying the area, is mostly associated with the presence of joints, fractures, and weathered zones (Issah, 2015;Aning et al, 2019). This is because the occurrence and movement of groundwater in the rock types of this formation are largely controlled by secondary pores (Yeleliere, 2018).…”

“…These techniques measure variations in physical properties such as resistivity, conductivity, velocity, density, and dielectric permittivity of the geologic media, which are influenced by porosity, degree of saturation, and quality of the water it contains. Among the geophysical techniques for groundwater prospecting, electrical resistivity (ER) and electromagnetic (EM) methods are the most popular techniques used for siting boreholes in Ghana (Aning et al, 2019;Issah, 2015).…”

“…The 1D VES technique, in particular, has been used widely used for the delineation of aquifers in different geologic formations (Ewusi and Kuma, 2011;Aning et al, 2019;Raji and Abdulkadir, 2020;Abdulrazzaq et al, 2020). Although this technique has been suitable and successful in siting boreholes in other parts of the country, it was unable to efficiently delineate suitable sites for drilling successful boreholes in some areas in the Asutifi North District.…”