Reply to discussion by RN Scoon and AA Mitchell on the paper “The Bushveld complex, South Africa: formation of platinum-palladium, chrome and vanadium-rich layers via hydrodynamic sorting of a mobilized cumulate slurry in a large, relatively slowly cooling, subsiding magma chamber” by WD Maier, S-J Barnes, and DI Groves

Abstract

Scoon and Mitchell express certain reservations about our paper. First, the authors suggest that in modeling the Bushveld reefs, we only appeal to hydrodynamic sorting, which they consider unimportant. Second, they feel that we have failed to fully acknowledge and understand the Mitchell and Scoon (2007) model for the Merensky Reef in which they proposed formation of the Merensky pyroxenite and other platinumgroup elements (PGE)-bearing horizons by injection of magma into semi-consolidated crystal piles. Third, the authors argue that we misrepresented their model for the origin of the platiniferous pipes. Our response to these points is the following: