Sulfur isotope fractionation in sulfide mineralization

Oxygen and sulfur isotope systematics of sulfate produced during abiotic and bacterial oxidation of sphalerite and elemental sulfur

“…Consistent with earlier studies (Gavelin et al, 1960;Nakai and Jensen, 1964;Taylor et al, 1984b;Rye et al, 1992), d 34 S SO 4 values from the aerobic biological ZnS and ZnS Fe experiments closely reflected the d 34 S values of the parent minerals (Table 8), indicating negligible sulfur isotope fractionation. In contrast, during the aerobic biological oxidation of S o , the sulfate produced was depleted in 34 S by 1.8 and 1.1& during the short and long term experiments, respectively (Tables 4 and 8).…”

Sulfur Isotope Geochemistry of Sulfide Minerals

“…The δ 34 S of resulting sulfate is indistinguishable from that of the parent sulfi de mineral; likewise, the isotopic composition of residual sulfi de minerals is unaffected (Gavelin et al 1960;Nakai and Jensen 1964;Field 1966;Rye et al 1992). Gavelin et al (1960) and Field (1966) documented similar sulfur isotope compositions among hypogene sulfi de ore minerals and various associated supergene sulfate minerals. A similar conclusion was reached regarding the relationship of aqueous sulfate with sulfi de minerals in acid mine drainage settings.…”

Oxygen and sulfur isotope systematics of sulfate produced by bacterial and abiotic oxidation of pyrite

“…Oxidation of sulfide minerals to sulfate at earth surface temperatures seems to be a quantitative and unidirectional process that produces negligible sulfur-isotope fractionation. This often results in d 34 S SO 4 values being indistinguishable from those of the parent sulfide minerals (Gavelin et al, 1960;Nakai and Jensen, 1964;Field, 1966;Rye et al, 1992). However, sulfur isotope fractionation during bacterial sulfide oxidation has been observed at low (Taylor et al, 1984b;Seal and Wandless, 1997) and high pH (Toran and Harris, 1989).…”