Integrated interpretation of aeromagnetic and aero-radiometric data to delineate structures and hydrothermal alteration zones associated with Gold and Base metal Mineralization in Chitipa area, Northern Malawi

Document Type : Research Paper


Department of Mining Engineering, Malawi University of Business and Applied Sciences, Blantyre, Malawi.



This study presents an analysis of aeromagnetic and aero-radiometric data from the Chitipa area in northern Malawi to delineate structures, hydrothermal alteration areas, and gold mineral potential zones, as well as to identify prospective regions for further mineral exploration.  Airborne geophysical data, specifically aeromagnetic and aero-radiometric data, were utilized. We applied several enhancements and filters to the geophysical data, including reduction to the pole, the first vertical derivatives, analytical signal, tilt angle derivative enhancements, Centre for Exploration Targeting (CET) grid analysis, Euler deconvolution, and radiometric data ratios. The results of the analysis provided detailed information on the subsurface geology and indicate that the area is characterized by faulting and shearing with structures predominantly trending in a northwest direction, and minor trends in the northeast-southwest, east-west, and north-south directions. Zones with hydrothermal alteration were found to coincide with structural associations in the NW part of the study area, indicating that the structures served as channel ways for migrating hydrothermal fluids that reacted with the rock formation, resulting in alteration. The northwest area is a promising mineralization zone, and further exploration should focus on this area.


Main Subjects

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