Sulfur isotope composition (δ34s ‰) in pyrite from the Novoafonskaya cave and its surroundings

Abstract

The findings of pyrite in the Novoafonskaya cave and its environs were studied using X-ray phase and mass spectrometric analyses. Pyrite oxidized from the surface, forming a coating of goethite on the outside. The pyrite of the Sushka village area is associated with marcasite. Sulfur (δ34S ‰) of pyrite is enriched in the light isotope; the isotopic composition varies from -14.21 to -34.86 δ34S ‰, CDT. According to these parameters, pyrite corresponds to the sulfur isotopic composition of ancient sedimentary pyrites from the stage of diagenesis of marine chemogenic sediments. Pyrite from the area of the Novoafonskaya cave cave was enriched in the light sulfur isotope as a result of fractionation during biogenic sulfate reduction at the stage of early sediment diagenesis and subsequently did not undergo epigenetic transformations.