Integrated geoscientific investigation of coal deposit for sustainable resource development, in part of northern Anambra basin, Nigeria

Abstract

This study presents an integrated geophysical investigation aimed at delineating coal seam occurrence within Ofugo, Ankpa Local Government Area of Kogi State, Nigeria. Electrical Resistivity Tomography (ERT), Vertical Electrical Sounding (VES), and Natural Electromagnetic Field (NEF EM) methods were employed to characterise subsurface lithology and identify coal bearing formations within the Anambra Basin. The results reveal a multi layered subsurface consisting of laterite, sandstone, shale, clay, and coal seams. Coal horizons are characterised by resistivity values ranging from 154 to 366 Ohm m, while NEF EM responses indicate conductive anomalies between 0.06 and 0.2. The coal seams occur at depths between 13 m and 40 m, with thickness ranging from 2 m to 6 m. Integrated interpretation reveals lateral continuity and structural dipping of shallow coal seam within the Mamu Formation which occur towards the southeastern portion of the study area. These findings further confirm the presence of economically viable coal deposits at shallow depth and highlight the effectiveness of integrated geophysical methods in mineral exploration which provides a framework in most resource evaluation.