Hydrogeophysics of Ikwuano from geoelectrical drilling and GPS measurements. – G.U. Chukwu and C.S. Okereke
Partial or non-availability of water has been a consistent preoccupation of the inhabitants of Ikwuano local government area. The need to boost the water supply system here is becoming very necessary in recent times. Geophysical measurements were carried out in this vicinity between January and April 2010. Using Schlumberger configuration, vertical electrical sounding (VES) and global positioning system (GPS) measurements were taken to study and verify the hydrogeological and hydrogeophysical nature, depth and thickness of the aquiferous zone in the area. Results of the study reveal that the study areas traverse two major geological units of Bende-Ameki and Benin Formations. Owing to variations in the subsurface crustal materials and the tectno-stratigraphic facies changes in this sedimentary terrain, the total drill depth (TDD) of boreholes, aquifer thickness and static water level (SWL) vary and were all determined. Boreholes thrive better in Benin Formation with thickness range of 18.4-163.4 meters than in Bende-Ameki Formation with aquifer thickness of 29.1-88.6 meters.