Boreskov

PP‐38FIRST MIKROIHNOFOSSILS FIND IN THE EARLY CAMBRIANVOLCANO‐HYDROTHERMAL FORMATION(KYZYL‐TASHTYG PYRITE ORE FIELD, TUVA, RUSSIA)Simonov V.A. 2 , Terleev A.A. 1 , Tokarev D.A. 1 , Kanygin A.V. 1 , Stupakov S.I. 21 A.A. Trofimuk Institute of Petroleum Geology and Geophysics SB RAS,630090, Novosibirsk, 3, Akademika Koptyuga Prosp. E‐mail: TerleevAA@ipgg.nsc.ru2 V.S. Sobolev Institute oа geology and mineralogy SB RAS,630090, Novosibirsk, 3, Akademika Koptyuga Prosp. E‐mail: Simonov@igm.nsc.ruKyzyl‐Tashtyg pyrite deposits (Tyva) has attracted attention of researchers due to thefact that in its structural‐geological features and the composition of ore, it has similaritieswith sulfide buildings hydrothermal fields at the bottom of modern marine basins. Of greatinterest is that the ore‐bearing volcanic‐sedimentary complexes of basalts and rhyolites oftumattayginskaya formation, synchronous with ore formation [1] are of Lower Cambrian age[2], that is field of Kyzyl‐Tashtyg deposit is a unique well‐preserved object, allowing toexplore the ancient submarine volcanic hydrothermal system, similar properties to themodern black smokers (chimneys). Of particular interest in tumattayginskaya formation findscause of microbial organisms (microihnofossils) in the amygdule of basalts at the base of themiddle part of the upper strata above mentioned formation. These organisms arefilamentous shape with a diameter of 5 to 25 microns, with a length of 500 microns.Filaments occur straight, curved, and branching. In rare cases, there contractions and cellularsructure of the filaments. Given the microscopic size, a simple morphology and similarity tomodern analogues, these microorganisms can be roughly classified as Cyanobacteria. At thesame time finding them in the amygdule of the rocks, in a confined space (the absence oflight) suggests their likely chemotrophic nature. It should further be noted that microbialorganisms are now known in ancient Archean pillow lavas [3, 4]. These microihnofossils arecharacteristic of Lower Cambrian deposits, where they have carbonate composition. In ourcase, which is extremely important microfossils are very different mineralogical composition.Studied in detail the samples is actually hydrothermal breccia. Fragments of basalt (up to 5cm) with amygdule, with microfossils, cemented by hydrothermal material of carbonatecomposition with albite. In this predominantly carbonate matrix are also disintegrated (likemelting, dissolving) relics (up to several mm) intensely chloritized and albitized basalts. Thus,according to these structural features and mineral composition, these breccias with201