Bushveld magmatic province-relationships between the conduit and main plutonic phases of intrusion

摘要

1 IntroductionThe 2.05 Ga Bushveld Igneous Complex (BIC) is the largest predominantly mafic intrusion on Earth. It is host to vast resources of the PGE, base and ferrous metals, and other mineralisation associated with granitic rocks, regional fluid flow derived and structurally hosted base and precious metal deposits. The discovery of massive sulphide mineralisation within the predominantly ultramafic Uitkomst Complex during 1990, and subsequent development of the Nkomati Mine highlighted yet another potential style of mineralisation associated with this remarkable intrusion. Ni-sulphide mineralisation developed within magma conduits, feeders, or satellite bodies to the BIC is a potentially important, but as yet not well understood source of Ni-PGE mineralisation. This paper briefly describes the structural and metallogenic aspects of the Uitkomst Complex, and then details another, as yet not well known, BIC satellite at Koster. These intrusions are then compared to the BIC magmatic event and bracketed into the evolution of this World class magmatic province.