Facies-Stratigraphic Distribution of Organic-Walled and Silicified Microfossils in the Early Billiyakh Basin (Lower Riphean, Anabar Uplift, Siberia)

Abstract

The sedimentary succession of the Anabar Uplift (North Siberia) contains the Early Riphean abundant and diverse microfossil assemblages. The Ust-Il’ya and lower Kotuikan organic-walled assemblages of prokaryotic and eukaryotic microorganisms from open shelf facies reflect the level of the marine biosphere evolution in the early Mesoproterozoic. The silicified microbiotas of the upper subformations of Kotuikan and Yusmastakh formations are represented by prokaryotic cyanobacteria only.