TY - JOUR

T1 - Vendian Taseeva Group, Southwestern Margin of the Siberian platform

T2 - Isotope, geochemical, and geochronological data, age, and correlation

AU - Kochnev, B. B.

AU - Proshenkin, A. I.

AU - Pokrovsky, B. G.

AU - Letnikova, E. F.

N1 - Funding Information: The research subject is coordinated with the research plans of the IGM SB RAS, IPGG SB RAS and GIN RAS. Geochemical and isotopic studies of carbonate sedimentary rocks were carried out with the support of grants RFBR № 19-05-00427 and 17-05-00418, as well as RSF № 17-17-01241. Geochronological study of detrital zircons was carried out with the support of grants of the RFBR № 18-05-00234 and 18-35-20025. The authors are grateful to D.B. Kochnev for assistance at field works, as well as to reviewers A.B. Kuzmichev and E.M. Khabarov for a number of comments and suggestions that contributed to the improvement of the original version of the article. Publisher Copyright: © 2020, V.S. Sobolev IGM, Siberian Branch of the RAS. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/10

Y1 - 2020/10

N2 - A high-amplitude negative δ13C anomaly (-11% V-PDB) has been found in the carbonate horizons of the Chistyakovka Formation of the Taseeva Group in the type sections of the southern Yenisei Ridge. The δ18O values (-2.7 to -5.4% V-PDB) and the lithologic features of carbonates indicate that these are primary sedimentary rocks and their isotope parameters reflect the primary isotope composition of the paleobasin waters. The negative δ13C excursion in the Chistyakovka Formation is close in stratigraphic position and amplitude to similar isotope excursion in the Vendian strata of the southern Siberian Platform and to the global middle Ediacaran Shuram- Wonoka anomaly. According to the data on clastic zircons, the age of the Chistyakovka Formation is no older than 580 Ma, which agrees with the earlier estimated age of the Shuram-Wonoka event. As follows from the data obtained, the age of the basement of the Taseeva Group is no older than 600 Ma. This provides a more accurate correlation of the Vendian complex along the southwestern margin of the Siberian Platform. The different stratigraphic scales of the sediments indicate that the marginal trough here began to form at different times (from late Riphean to late Vendian), which explains its segmented structure.

AB - A high-amplitude negative δ13C anomaly (-11% V-PDB) has been found in the carbonate horizons of the Chistyakovka Formation of the Taseeva Group in the type sections of the southern Yenisei Ridge. The δ18O values (-2.7 to -5.4% V-PDB) and the lithologic features of carbonates indicate that these are primary sedimentary rocks and their isotope parameters reflect the primary isotope composition of the paleobasin waters. The negative δ13C excursion in the Chistyakovka Formation is close in stratigraphic position and amplitude to similar isotope excursion in the Vendian strata of the southern Siberian Platform and to the global middle Ediacaran Shuram- Wonoka anomaly. According to the data on clastic zircons, the age of the Chistyakovka Formation is no older than 580 Ma, which agrees with the earlier estimated age of the Shuram-Wonoka event. As follows from the data obtained, the age of the basement of the Taseeva Group is no older than 600 Ma. This provides a more accurate correlation of the Vendian complex along the southwestern margin of the Siberian Platform. The different stratigraphic scales of the sediments indicate that the marginal trough here began to form at different times (from late Riphean to late Vendian), which explains its segmented structure.

KW - C-chemostratigraphy

KW - Ediacaran

KW - Shuram-Wonoka anomaly

KW - Siberian Platform

KW - Taseeva Group

KW - U-Pb dating of detrital zircons

KW - Vendian

KW - CARBON

KW - SEQUENCES

KW - Siberian Platfonn

KW - YENISEI RIDGE

KW - VOROGOVKA GROUP

KW - PB

KW - CHEMOSTRATIGRAPHY

KW - EVOLUTION

KW - STRATOTYPE

KW - lidiacaran

KW - DETRITAL ZIRCONS

KW - PATOM COMPLEX

UR - http://www.scopus.com/inward/record.url?scp=85095762539&partnerID=8YFLogxK

U2 - 10.15372/RGG2019142

DO - 10.15372/RGG2019142

M3 - Article

AN - SCOPUS:85095762539

VL - 61

SP - 1121

EP - 1135

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 10

ER -