Research output: Contribution to journal › Article › peer-review
Quo vadis, Tommotian? / Grazhdankin, Dmitriy V.; Marusin, Vasiliy V.; Izokh, Olga P. et al.
In: Geological Magazine, Vol. 157, No. 1, 0016756819001286, 01.01.2020, p. 22-34.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Quo vadis, Tommotian?
AU - Grazhdankin, Dmitriy V.
AU - Marusin, Vasiliy V.
AU - Izokh, Olga P.
AU - Karlova, Galina A.
AU - Kochnev, Boris B.
AU - Markov, Georgiy E.
AU - Nagovitsin, Konstantin E.
AU - Sarsembaev, Zhiger
AU - Peek, Sara
AU - Cui, Huan
AU - Kaufman, Alan J.
N1 - Publisher Copyright: © Cambridge University Press 2019. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - The concept of the Tommotian Regional Stage of the Siberian Platform has been closely linked to the idea of the 'Cambrian Explosion' of animals and protists when the entire Earth system shifted rapidly into Phanerozoic mode. We conducted a multidisciplinary study of an informal 'synstratotype' of the lower Tommotian boundary in the upper Mattaia Formation, Kessyusa Group in the Olenek Uplift, NE of the Siberian Platform. The Mattaia Formation characterizes an upper shoreface to inner-shelf depositional setting and provides important faunal ties and correlation with carbonate-dominated and aliminosiliciclastic open-shelf areas. A section of the upper Mattaia Formation at Boroulakh, Olenek River is suggested here as a model for the Global Boundary Stratotype Section and Point for the base of the Cambrian Stage 2. This level contains the lowermost occurrence of the cosmopolitan fossil helcionelloid mollusc Aldanella attleborensis. Section global markers near the base of the stage include a positive excursion of δ13C values reaching +5.4‰, a U-Pb zircon date of 529.7 ± 0.3 Ma, massive appearance of diverse small skeletal fossils (including Watsonella crosbyi), a sudden increase in diversity and abundance of trace fossils, as well as a conspicuous increase in depth and intensity of bioturbation. Coincidently, it is this level that has always been regarded as the lower Tommotian boundary on the Olenek Uplift.
AB - The concept of the Tommotian Regional Stage of the Siberian Platform has been closely linked to the idea of the 'Cambrian Explosion' of animals and protists when the entire Earth system shifted rapidly into Phanerozoic mode. We conducted a multidisciplinary study of an informal 'synstratotype' of the lower Tommotian boundary in the upper Mattaia Formation, Kessyusa Group in the Olenek Uplift, NE of the Siberian Platform. The Mattaia Formation characterizes an upper shoreface to inner-shelf depositional setting and provides important faunal ties and correlation with carbonate-dominated and aliminosiliciclastic open-shelf areas. A section of the upper Mattaia Formation at Boroulakh, Olenek River is suggested here as a model for the Global Boundary Stratotype Section and Point for the base of the Cambrian Stage 2. This level contains the lowermost occurrence of the cosmopolitan fossil helcionelloid mollusc Aldanella attleborensis. Section global markers near the base of the stage include a positive excursion of δ13C values reaching +5.4‰, a U-Pb zircon date of 529.7 ± 0.3 Ma, massive appearance of diverse small skeletal fossils (including Watsonella crosbyi), a sudden increase in diversity and abundance of trace fossils, as well as a conspicuous increase in depth and intensity of bioturbation. Coincidently, it is this level that has always been regarded as the lower Tommotian boundary on the Olenek Uplift.
KW - biostratigraphy
KW - Cambrian Stage 2
KW - chemostratigraphy
KW - Olenek Uplift
KW - Siberian Platform
KW - PRECAMBRIAN-CAMBRIAN BOUNDARY
KW - OLENEK UPLIFT
KW - NORTHEASTERN-SIBERIAN-PLATFORM
KW - STAGE
KW - INTERNATIONAL-COMMISSION
KW - RADIATION
KW - CARBON-ISOTOPE STRATIGRAPHY
KW - CHRONOSTRATIGRAPHY
KW - BIOSTRATIGRAPHICAL CONSTRAINTS
KW - RIVER SECTION
UR - http://www.scopus.com/inward/record.url?scp=85078045251&partnerID=8YFLogxK
U2 - 10.1017/S0016756819001286
DO - 10.1017/S0016756819001286
M3 - Article
AN - SCOPUS:85078045251
VL - 157
SP - 22
EP - 34
JO - Geological Magazine
JF - Geological Magazine
SN - 0016-7568
IS - 1
M1 - 0016756819001286
ER -
ID: 23208790