The Delineation of Mineralization and hydrothermal Alteration Zones in Gitata Sheet 187, North Central Nigeria

Abstract

This paper presents the delineation of potential mineralization and hydrothermal alteration zones within Gitata sheet (187) in north central Nigeria using airborne geophysical data. Aeromagnetic and aero radiometric data of high resolution covering the area were acquired and analyzed by mapping possible areas of mineralization, structures and hydrothermal alteration. The enhancement techniques applied to the data were the Analytical signal and Centre for Exploration Targeting (CET). The maps of radioelements and their rations were used in the analysis. Structural analysis showed the dominant structural pattern within the study area to be NE-SW and NW-SE while the northwest and central portions of the study area were correlated with a strong analytical signal of 0.161 amplitude. Favorable mineralization zones were mapped from complex structural analyses and correlated with areas of high analytical signal within the northwest and central portion of the study area. Inspection of aero radiometric maps helped to delineate hydrothermal alteration zones that predominate in undifferentiated older granite, Migmatite and Gneiss followed by some occurrences within the porphyritic granites in the eastern part of the study area and the pelitic schist/Muscovite having some occurrence of the hydrothermal zones delineated. Areas with strong analytic signal and complex structures are considered to be favorable for mineralization as mineralization fluids may have solidified in the structures and also alter the composition of the host and adjacent rocks