ASSESSMENT OF SUBSURFACE STRATIGRAPHY USING 2- DIMENSIONAL ELECTRICAL RESISTIVITY IMAGING IN THE UNIVERSITY OF BENIN TEACHING HOSPITAL, BENIN CITY.

ABSTRACT

This study presents the results of an investigation conducted in the Golf Course Area of the University of Benin Teaching Hospital, aimed at determining aquifer depths and providing 5 detailed geophysical and geological insights using electrical resistivity tomography (ERT). The objectives of the research were to map subsurface geological structures, evaluate soil bearing capacity, and identify areas with geotechnical hazards affecting future construction stability. Through the utilization of the Wenner-Schlumberger Array, resistivity tomography along traverse 11 revealed varied subsurface layers with resistivities ranging from 813 Ωm to 9940 Ωm. The investigation identified distinct layers, including moist topsoil, dry sand, and an anomalous high-resistivity silt lens, each with unique resistivity ranges and depth extents. These findings provided critical insights into aquifer depths, subsurface geological structures such as fractures and voids, and soil characteristics influencing construction stability. The transition from moist topsoil to dry sand and the presence of a high-resistivity silt lens were particularly noteworthy, offering valuable information for understanding groundwater dynamics, assessing soil bearing capacities, and identifying potential geotechnical hazards. The study's alignment with its aims and objectives underscores the effectiveness of ERT in geophysical explorations and highlights its importance in guiding informed decision-making for sustainable development in the study area. Overall, this research contributes to the comprehensive understanding of the subsurface geophysical and geological framework of the Golf Course Area, emphasizing the critical role of electrical resistivity tomography in environmental and engineering geophysics. The insights gained from this study are essential for managing groundwater resources, planning construction projects, and mitigating geotechnical risks, thereby facilitating sustainable development and infrastructure planning in the University of Benin Teaching Hospital area.