A sedimentary barite deposit from the Archean Fig Tree Group of the Barberton Mountain Land (South Africa)

Abstract

Petrographic, stratigraphic, and structural evidence is presented for the sedimentary origin of one of the oldest known stratiform barite deposits. The setting of the barites within the Fig Tree Group of the Swaziland Supergroup (> 3.2 b.y.) is outlined in terms of a new concept. The barite was deposited on a narrow submarine ridge zone. This Proto-Inyoka Zone separated a graywacke facies from a shallow-water facies within the Fig Tree basin.