Abstract
A low-grade, copper-iron sulfide deposit is present at Boksputs in the Northwest Cape, South Africa. It occurs in the Proterozoic amphibolite belt, the Areachap Group, along the eastern margin of the Namaqua mobile belt.
The mineralization, which is dominated by pyrite, chalcocopyrite, sphalerite, and magnetite, occurs as disseminated ore and thin layers of massive-type ore in the lower massive amphibiolite and associated amphibole gneisses of the Kraalkop antiform and synform.
Chemically, the host-rock amphibolite resembles low-K arc tholeiite and calc-alkaline volcanics, whereas the upper amphibolite is calc-alkaline.
The sulfide mineralization and the host-rock composition is explained in terms of modern plate tectonic principles. It is concluded that the Boksputs mineralization is a syngenetic, strata-bound, copper-iron deposit which to some extend resembles Besshi-type deposits. It is associated with low-K arc tholeiite which is tectonically related to a front arc environment or a rifted arc system along the eastern margin of the Namaqua mobile belt.
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Geringer, G.J., Pretorius, J.J. & Cilliers, F.H. Strata-bound copper-iron sulfide mineralization in a Proterozoic front arc setting at Boksputs, Northwest Cape, South Africa — a possible Besshi-type deposit. Mineral. Deposita 22, 81–89 (1987). https://doi.org/10.1007/BF00204684
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DOI: https://doi.org/10.1007/BF00204684