Journal of Emerging Trends in Engineering and Applied Sciences: Research Areas

Abstract:
In the early 50s Igarra used to be a village. Now it has grown to be a local government headquarters of administrative, educational, religious, cultural, and mining significance with increasing population and water demand. Lack of adequate water supply has become acute more because the town is lying on the Basement Complex igneous and metamorphic geology in which the groundwater occurrence is difficult to access. The little available surface water source (Ojerami Dam) had failed severally. The purpose of this research is to elucidate the hydrogeology of this area that would provide baseline data, facilitate successful management and sourcing of groundwater supplements/alternatives for sustainable socioeconomic development of the area. Geophysical vertical electrical sounding VES of Schlumberger array was used in four locations to investigate for groundwater in Igarra Formation of the Basement Complex. Lithologic logs of the area were used as guide and they compared fairly well with the geo-electric layers obtained. Eight (08) geo-electric layers were distinguished in VES 1, and six (06) each in VES-2, VES-3, and VES-4 areas all indicating a single confined aquifer under-lying Igarra town with resistivity values of 58.05, 129.9, 441.4 and 125.7 ohm-m at VES 1-4 points respectively. This research showed that the aquifer system is constituted by highly weathered and fractured metamorphic rocks viz metasedments, quartz-schists, and gneiss at depths of 15.1m at VES-1, 6.7m at VES-2, 5.5m at VES-3 and 24.36m at VES4 and can be classified as weathered layer aquifer type. At VES-3 the depth to aquifer (5.5m) is comparatively shallow and aquifer thickness (18.9m) is appreciable, the area would cost less for drilling boreholes and with higher prospects for higher yield, the area is thus considered the target-zone for sourcing groundwater in Igarra Town.

Keywords: geophysical exploration vertical electrical sounding ves basement complex groundwater Igarra.

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