“…2.2 Á/2.1 Ga (Karhu, 1993). Globally, Paleoproterozoic carbonate units correlative with the Nash Fork Formation based on similar carbon isotope systematics are also known, as discussed above from South Africa (Master et al, 1993;Buick et al, 1998;Swart, 1999;Bekker et al, 2001a) as well as Gabon (Gauthier-Lafaye and Weber, 1989), Zimbabwe (Bekker et al, 2001b), Australia (Lindsay and Brasier, 2002), India (Sreenivas et al, 2001), Scotland (Baker and Fallick, 1989a), Brazil (Sial et al, 2000), Russia (Akhmedov et al, 1996), and North America (Melezhik et al, 1997a;Bekker, 1998;Hofmann and Davidson, 1998).…”