DELINEATION OF AIRBORNE MAGNETIC AND RADIOMETRIC STRUCTURES ASSOCIATED WITH GOLD MINERALIZATION OF MINNA AND ITS ENVIRONS, NORTHCENTRAL NIGERIA

Abstract

This study utilized the interpretation of the airborne magnetic and radiometric data to delineate the potential structures that are associated with gold mineralization of the Minna and its environs, Northcentral Nigeria. The total field anomaly data was reduced to pole and upward continued in a bid to well positioned and enhanced the shallow (high pass) magnetic structures. The high pass structural lineaments were extracted and the resulting prominent E-W and NE-SW tectonic trends were revealed which are perhaps related to Eburnean (D1) and Pan-African (D2) deformation events respectively. Subsequently, numerous regions with relatively high degree of faulting and shearing effects were unraveled from the line density analysis of the high pass lineaments. The 3-D Euler deconvolution technique provides a synonymous trend pattern with the HP lineaments as well as estimate the depth extents to the potential structures with values varying between 82.7 and 211.9 m. It was found that the mineralized structures associated with gold over the study area interact with the hydrothermal fluids alongside/adjacent to the structurally deformed (relatively high degree of faulting and shearing effects) regions. The observed regions with coincident, of the hydrothermally altered and structurally deformed are therefore marked as the resourceful, structures for gold mineralization. Hence, the derived evidence from this study has updated the information on the structures that are associated with gold mineralization and also acts a mitigation major against the indiscriminate excavations of the studied region.