EVIDENCE OF MICROBIAL-INDUCED MINERALIZATION IN THE ROCKS OF THE TOMTOR CARBONATITE COMPLEX (ARCTIC SIBERIA)
Carbonates of the Tomtor complex of ultrabasic alkaline rocks and carbonatites (north of the Republic of Sakha-Yakutia) are distinguished by a wide range of carbon isotopic composition δ13C from +2 to –59.9‰. The paper gives a description of the geological position, localization patterns, mineral and chemical composition, relationship with REE mineralization of samples with δ13C carbonates from –25 to –59‰. The formation of abnormally low δ13C in carbonates is due to the biogenic oxidation of methane from δ13Cmet to –70‰.