The Karibib region as an emerging gold district in the Damara Belt, Namibia: a review and regional interpretation of controls on mineralization

Abstract Recent discoveries around existing gold deposits and prospects demonstrate the significance of the Karibib region in the south Central Zone of the Pan-African Damara Belt in central Namibia as an emerging gold district. This paper aims to identify the underlying structural and lithological controls of the gold mineralization in individual deposits and prospects. Gold occurrences throughout the region are hosted by the lithologically heterogeneous, amphibolite-facies, carbonate-siliciclastic metasedimentary sequence of the Neoproterozoic Swakop Group. Gold is exclusively associated with quartz-vein systems and associated sulfides, primarily pyrrhotite, arsenopyrite, pyrite, and minor chalcopyrite. The geometry of the vein systems varies systematically between deposits and prospects but shows close relationships with the main generation of east-northeasterly trending folds and thrusts that formed during the main phase of northwest-southeast directed, subhorizontal shortening (D 2/3 ) between ca. 530 − 510 Ma. Sites of economic gold mineralization correspond to a combination of (1) contacts between rock types of distinctly contrasting rheology along which strain localization promoted fracturing and veining in more competent rocks, (2) high-strain zones that localized regional fluid flow, mainly along steep fold limbs of regional-scale folds, and (3) regional-scale deflections of wall-rock structures and jog-like geometries that resulted in either dilational or contractional structural sites. It is the combination and interplay of these factors that control the formation of auriferous quartz-vein systems in the Karibib region.