Some aspects of the sedimentary and diagenetic environment of Proterozoic banded iron-formation

The various mineral assemblages of Proterozoic banded iron-formations, as represented by the sulfide, silicate, carbonate, and oxide facies, are evaluated in terms of stability diagrams at 25 degrees C and one atmosphere pressure. The observed assemblages, which are considered to be of sedimentary and diagenetic origin, are equivalent to the equilibrium coexistences predicted by the stability calculations. It appears that several aspects of the physicochenlical environments of some present-day sedimentary basins are similar to those which probably prevailed during Proterozoic time.