Integrated lithostructural mapping of the Rössing area, Namibia using high resolution aeromagnetic, radiometric, Landsat data and aerial photographs

Abstract

This paper presents results of an integrated appraisal of recent high-resolution aeromagnetic, radiometric and remote sensing data over the Rössing mine area and lower Khan Gorge region of Namibia. The interpretation used stereoscopic aerial photographs to establish structure around the Rössing mine and high-pass filtered aeromagnetic data for the regional structure, followed by analysis of spectral Landsat TM data, total field magnetic intensity data and imaged airborne gamma-ray spectrometer data to delineate lithology. Resulting interpretation maps clearly show an hierarchy of polyphase folding, which had been described by earlier field mapping, and a hitherto-unrecognised system of late (post-F3) sinistral strike-slip faulting and thrusting. Early Palaeozoic alaskitic intrusions of the type which host the world-class Rössing uranium deposit appear to be largely related to late sinistral transtensional ladder veins associated with the north-northeast trending post-F3 sinistral strike-slip faults.