TY - JOUR

T1 - Resolving Terreneuvian stratigraphy in subtidal–intertidal carbonates

T2 - palaeontological and chemostratigraphical evidence from the Turukhansk Uplift, Siberian Platform

AU - Marusin, Vasiliy V.

AU - Kochnev, Boris B.

AU - Karlova, Galina A.

AU - Nagovitsin, Konstantin E.

N1 - Publisher Copyright: © 2019 Lethaia Foundation. Published by John Wiley & Sons Ltd

PY - 2019/10/1

Y1 - 2019/10/1

N2 - Both diverse assemblages of small skeletal fossils and a representative chemostratigraphical record make the Siberian Platform widely regarded as one of the key regions for the reconstruction of global biotic and abiotic events in the late Ediacaran and early Cambrian. However, the wide distribution of intertidal–subtidal facies in the Ediacaran–Cambrian transitional strata of the central and southwestern Siberian Platform (Turukhansk–Irkutsk–Olekma facies region) produces a dramatic depletion of the palaeontological record and considerably limits their age-calibration and long-distance correlation. We report new lithological, palaeontological and carbonate carbon-isotope data for the Ediacaran–Cambrian sections of the Turukhansk Uplift (northwestern Siberian Platform, western facies region). These data provide a robust framework for the chemostratigraphical correlation of the western facies region with sections of the transitional and eastern regions of the Siberian Platform and further confirms a depositional hiatus at the base of the Tommotian Stage in the stratotype section (Aldan River, SE Siberia). The carbon-isotope curve from the Turukhansk Uplift sections correlates positively with the most chemostratigraphically representative Ediacaran–Cambrian sections (Siberia, Morocco, South China). It records major carbon-isotope oscillations globally recognized in the lower Cambrian, enabling localization of the Fortunian and Cambrian Stage 2 boundaries in the Platonovskaya Formation. Although there is extreme paucity and poor preservation of the small skeletal fossils in the western facies region, we report individual Barskovia, Blastulospongia and chancelloriid sclerites from the Platonovskaya Formation. A combination of palaeontological and chemostratigraphical data suggests the base of P. antiqua Assemblage Zone is located in the middle Platonovskaya Formation. The earliest spiral gastropods probably occurred at ~541 Ma, as demonstrated by the discovery of a specimen of Barskovia near the base of the large negative excursion in the lower Platonovskaya Formation, correlated with the BACE negative carbon-isotope peak in the sections of the Yangtze Platform.

AB - Both diverse assemblages of small skeletal fossils and a representative chemostratigraphical record make the Siberian Platform widely regarded as one of the key regions for the reconstruction of global biotic and abiotic events in the late Ediacaran and early Cambrian. However, the wide distribution of intertidal–subtidal facies in the Ediacaran–Cambrian transitional strata of the central and southwestern Siberian Platform (Turukhansk–Irkutsk–Olekma facies region) produces a dramatic depletion of the palaeontological record and considerably limits their age-calibration and long-distance correlation. We report new lithological, palaeontological and carbonate carbon-isotope data for the Ediacaran–Cambrian sections of the Turukhansk Uplift (northwestern Siberian Platform, western facies region). These data provide a robust framework for the chemostratigraphical correlation of the western facies region with sections of the transitional and eastern regions of the Siberian Platform and further confirms a depositional hiatus at the base of the Tommotian Stage in the stratotype section (Aldan River, SE Siberia). The carbon-isotope curve from the Turukhansk Uplift sections correlates positively with the most chemostratigraphically representative Ediacaran–Cambrian sections (Siberia, Morocco, South China). It records major carbon-isotope oscillations globally recognized in the lower Cambrian, enabling localization of the Fortunian and Cambrian Stage 2 boundaries in the Platonovskaya Formation. Although there is extreme paucity and poor preservation of the small skeletal fossils in the western facies region, we report individual Barskovia, Blastulospongia and chancelloriid sclerites from the Platonovskaya Formation. A combination of palaeontological and chemostratigraphical data suggests the base of P. antiqua Assemblage Zone is located in the middle Platonovskaya Formation. The earliest spiral gastropods probably occurred at ~541 Ma, as demonstrated by the discovery of a specimen of Barskovia near the base of the large negative excursion in the lower Platonovskaya Formation, correlated with the BACE negative carbon-isotope peak in the sections of the Yangtze Platform.

KW - carbon isotopes

KW - correlation

KW - Ediacaran–Cambrian transition

KW - Siberian Platform

KW - Terreneuvian

KW - Turukhansk Uplift

KW - PRECAMBRIAN-CAMBRIAN BOUNDARY

KW - EARLY HISTORY

KW - OLENEK UPLIFT

KW - Ediacaran-Cambrian transition

KW - SUKHARIKHA RIVER SECTION

KW - INTEGRATED CHRONOSTRATIGRAPHY

KW - SKELETAL FOSSIL ASSEMBLAGES

KW - SOUTH CHINA

KW - ISOTOPIC COMPOSITION

KW - EASTERN YUNNAN

KW - SR

UR - http://www.scopus.com/inward/record.url?scp=85060798756&partnerID=8YFLogxK

U2 - 10.1111/let.12325

DO - 10.1111/let.12325

M3 - Article

AN - SCOPUS:85060798756

VL - 52

SP - 464

EP - 485

JO - Lethaia

JF - Lethaia

SN - 0024-1164

IS - 4

ER -