MESO - NEOPROTEROZOIC BACTERIAL MICROFOSSILS FROM THE SUKHAYA TUNGUSKA FORMATION OF THE TURUKHANSK UPLIFT, RUSSIA

Abstract

The stratiform stromatolitic cherts from the Meso—Neoproterozoic Sukhaya Tunguska Formation (ca. 1,100–900 Ma) of the Turukhansk Uplift, Russia, preserve an abundant and varied record of ancient microbial life. The assemblages found in the silicified stratiform stromatolites are dominantly composed of empty sheaths of filamentous bacteria and envelopes of coccoid ones, most of which are interpreted as ancient cyanobacterial remains. Three filamentous species (Siphonophycus kestron, S. inornatum, S. robustum) belonging a single genus were identified, while five coccoid species belonging to 3 genera (Glenobotrydion aenigmatis, Gloeodiniopsis lamellosa, G. sp.,Myxococcoides grandis, M. minor, Eoentophysalis sp.) were documented.