ABSTRACT
The Rosh Pinah ore province in southwestern Namibia, which hosts two known world-class Zn-Pb deposits, is located in the 580 - 540 Ma Pan-African Gariep Belt. Base metal sulphide mineralisation is of a sedimentary-exhalative to early diagenetic replacement nature and is associated with and related to predominantly felsic 741 Ma rift volcanism. It is hosted by a ∼770 - 740 Ma clastic rift graben fill and overlying shallow marine, largely calcareous sedimentary rocks. A detailed chemostratigraphic study revealed that favourable conditions for metal enrichment of the sediment host were controlled by the interplay between rift-drift tectonics and climatically induced sea level fluctuations. Orogenic fluid flow during regional dynamic metamorphism following continent collision around 545 Ma was not pervasive and the fluid composition was not favourable for large-scale mobilisation of the Zn-Pb ore minerals.
