Elemental sulfur formation related to celestine reduction: An example of biomineralization of bacterial origin

This study investigates the disseminated elemental sulfur formation in cele stine mineralization in the upper member of the Bozbel Formation (Eocene) i n the Sivas basin, Turkey. Optical and scanning electron microscope studies indicate that the sulfur minerals have three main morphologies including l acy, grape-like, and spheroidal - lobous types structures. These sulfur str uctures are occasionally coated with organic matter. Total organic carbon a nd infrared spectrometry studies indicate that an average of 1 % organic ma tter in this sulfur is of biogenic origin. Detailed studies on these elemen tal sulfur deposits suggest that the sulfur was formed by the reduction of celestine through the metabolic activities of sulfate reducing bacteria Thi s observation is supported by the trace element values obtained through x-r ay fluorescence analyses on both the celestine and the elemental sulfur sam ples.