THE DEPTH TO THE SHALLOW WATER TABLE IN ADO-EKITI (EKSU), NIGERIA, USING THE SEISMIC REFRACTION METHOD

Groundwater is a critical resource for domestic, agricultural, and industrial activities, particularly in regions with fluctuating precipitation patterns and increasing water demand (Freeze and Cherry, 1979). In Ado-Ekiti, Nigeria, the reliance on groundwater as a primary source of potable water necessitates an accurate assessment of the depth to the water table for sustainable resource management and efficient borehole drilling (Olorunfemi and Fasuyi, 1993). Understanding the spatial variation in the water table is essential for mitigating water scarcity challenges and optimizing groundwater exploitation strategies (Todd and Mays, 2005). Seismic refraction, a widely used geophysical technique, has proven effective in delineating subsurface lithology and identifying the depth to the water table in various geological settings (Telford et al., 1990). The method relies on the principle that seismic waves propagate at different velocities depending on the density and elastic properties of subsurface materials. A significant reduction in seismic velocity is often associated with the transition from unsaturated to saturated zones, making the technique suitable for groundwater investigations (Sheriff and Geldart, 1995). In urban and semi-urban areas like Ado-Ekiti, where rapid development and population growth exert pressure on groundwater resources, conventional trial-and-error drilling methods are inefficient and economically unviable (Olayanju et al., 2011). Seismic refraction surveys offer a cost-effective and non-invasive approach to subsurface characterization, facilitating informed decision-making in groundwater exploration (Reynolds, 2011). By integrating seismic refraction data with hydrogeological assessments, this study aims to determine the shallow water table depth in Ado-Ekiti, providing critical insights for sustainable groundwater management and borehole siting. 1.2 Problem Statement Groundwater is a vital source of potable water in Ado-Ekiti, Nigeria, where rapid urbanization and population growth have increased the demand for reliable and sustainable water supply. However, the occurrence and distribution of groundwater in the area are largely influenced by the underlying Precambrian basement complex rocks, which exhibit low primary porosity. As a result, groundwater is mainly confined to weathered and fractured zones, making its exploration challenging and uncertain (Olorunfemi and Fasuyi, 1993).