Geoelectric investigation of the aquifer characteristics and groundwater potential in Kwale, Delta State, Nigeria
Oseji, J.O.; Atakpo, E.A.; Okolie, E.C.
Journal of Applied Sciences and Environmental Management 9(1): 157-160
2005
Document Number: 260044
Subsurface geo-electrical survey using the electrical resistivity (VES) method and drillers logs were carried out in Kwale, Ndokwa West Local Government Area of Delta State, Nigeria, to investigate the aquifer characteristics and groundwater potential of the subsurface formations. Nineteen vertical electrical soundings were carried out within the town and its environment using the Schlumberger array configuration. The data was interpreted using the conventional curve matching and computer iteration method. The results reveal a five layer HKH, KQH and AKH type curves. The true resistivity of the top soil varies from 55-236 Omega m while the thickness varies from 0.7-1.0 m. The second layer has resistivity ranging from 37-627 and thickness ranging from 1.3-3.6 m. This layer is composed of clay to sand. The third layer, which constitutes an aquifer, has resistivity varying from 2.7 to 411 Omega m while the thickness varies from 4-17 m. It is composed of fine-grained sand. The fourth geoelectric layer has resistivity values ranging from 114 to 168 Omega m while the thickness varies form 15 to 35 m. This layer is composed of fine to medium-grained sand. The soft layer has resistivity ranging from 326-2308 Omega m. This layer is composed of medium coarse-grained soil and it constitutes an aquifer of very good quality groundwater. The average depth of this aquifer is between 30-40 m. These results were correlated with lithological logs from boreholes drilled in the study areas and were found to be consistent.