Resistivity Survey for Identification of Clay Deposits in Akwa Ibom State

This study applies electrical resistivity surveying to identify and characterise clay deposits suitable for industrial ceramic and brick production in Akwa Ibom State, South South Nigeria. Akwa Ibom State's coastal plain sands and alluvial sediments contain clay intercalations that have potential for industrial exploitation, but their spatial distribution and thickness require detailed investigation before extraction can be planned. This study deploys a combination of Schlumberger VES and constant separation traversing along 12 profiles covering 14.4 kilometres of ground in Ini, Essien Udim, and Obot Akara local government areas. Twenty VES stations are acquired with maximum AB/2 of 100 metres. The CST profiles use AB of 20 metres to detect lateral clay body extent at shallow depths. Interpreted resistivity sections are correlated with three shallow hand-dug pits that expose the local stratigraphy. Findings reveal resistivity ranges of 3 to 12 ohm-metres associated with wet clay materials at depths between 1.5 and 15 metres, distinguishable from overlying dry sands (50 to 200 ohm-metres) and underlying compact sands (150 to 600 ohm-metres). Two discrete clay bodies of approximately 450 and 320 metres lateral extent are delineated in the Essien Udim area, with thicknesses between 6 and 12 metres. Geotechnical sampling from the trial pits confirms high plasticity index and alumina content meeting specifications for ceramic grade clay. The study recommends the Essien Udim deposit for detailed resource estimation using targeted augering and recommends the resistivity method as a cost-effective pre-extraction clay prospecting tool.

Keywords: resistivity survey, clay deposits, ceramic production, Akwa Ibom State, lateral delineation.