(Table 2) Concentrations and isotopic compositions of pyrite and sulfate sulfur in argillaceous sediments outside the gas hydrate seep zone, Sea of Okhotsk

Isotopic analysis of organic matter from bottom sediments and soft tissues of bivalve Conchocoele from a community near the gas-hydrate seep off the Paramushir Island indicates that the intramolecular energy of energy-rich compounds H2S and methane, which are products of early diagenesis, is used for chemical synthesis by free-living symbiotic sulfur-oxidizing, sulfur reducing, and methane-oxidizing bacteria in the community.