Your Cart

Your cart is empty

Home  >  Volume 31 (July 2015)

Geophysical Image Investigation of Salt/Brackish Water Intrusion into Freshwater Aquifer in Lagooncoastal Region: A Case Study of University of Lagos, Nigeria by Olorode D. O.and Ugwoke C.C (Pages 291-300)
Sale price: $5.00


Groundwater is very essential to humans from all ages. Many factors affect the quality of groundwater aquifer, these include contamination by salt-water intrusion or by toxic industrial/chemical wastes. An assessment of the University of Lagos campus ground water was done using geo-electrical resistivity survey. A total of six electrical imaging lines were traversed with Wennerarray coupled with ten vertical electrical soundings (VES) within the area. The Schlumberger electrode array with current electrode half spacing from 1 to 100m was used to acquire 1D data. For the 2D field surveys, Wenner 64 electrode spread was used, while the spacing between adjacent electrodes ranged from 1.5 to 3.0m. Interpretations include quantitative and qualitative deductions from 1D and 2D geoelectric models. Two software packages were utilized for the analyses in this study: WinResist for 1D plotting andRES2DINV for 2D inversion. The depth of the saline/freshwater interface varied from 6.9 to 64.0m and the thickness of the saline water was greater in the proximity of the coastline.The resistivity inverse model of various positions (1.04-20.0m depth) exposed the zone of brackish/saline water.Two major freshwater aquifers were delineated and they occurred unprotected.

Keywords: Salinity, vertical electrical sounding (VES), 2D profiles, coastal region