A.I. Varlamov, A.Yu. Rozanov, A.L. Makarova, D.A. Komlev, S.S. Sukhov
Optimization of the Cambrian System in the General stratigraphic chart of Russia
DOI 10.47148/0016-7894-2025-1-47-65
Key words: stages of Cambrian; stratotypes of the Molodian, Chayian, Tiksian, Bulunian, Omnian, Mokuteian, Novotukalandian stages; Siberian Platform.
For citation: Varlamov A.I., Rozanov A.Yu., Makarova A.L., Komlev D.A., Sukhov S.S. Optimization of the Cambrian System in the General stratigraphic chart of Russia. Geologiya nefti i gaza. 2025;(1):47–65. DOI: 10.47148/0016-7894-2025-1-47-65. In Russ.
The authors discuss optimization of the Cambrian part of General stratigraphic chart of Russia in accordance with the revised requirements to methodology of its creation. Stratotypes of all the stages are defined in the Siberian Platform sections, they have complete stratigraphy volumes, underlying and overlying deposits and they successively build on each other; so, there are no problems in their correlation. The three lower stages of the Lower Cambrian – Tommotian, Atdabanian and Botomian – are preserved in the traditional sense. The lower boundary of the Toyonian Stage is moved one zone upwards – to the bottom of Lermontovia grandis Zone. Four following stages are proposed in the Middle Cambrian: Amgaian (Molodian) (Ovatoryctocara granulata, Kounamkites, Ptychagnostus gibbus zones), Chayian (Tomagnostus fissus – Ptychagnostus atavus and Ptychagnostus punctuosus – Linguagnostus grönwalli zones), Tiksian (Centropleura loveni – Anomocarioides limbataeformis and Lejopyge laevigata – Aldanaspis truncata zones), Bulunian (Proagnostus bulbus, Clavagnostus spinosus, Glyptagnostus stolidotus zones). And in the Upper Cambrian: Omnian (Glyptagnostus reticulatus, Stigmatoa destructa, Erixanium sentum zones), Mokuteian (Pseudoglyptagnostus clavatus – Irvingella angustilimbata, Mokutella mokuteica, Irvingella cipita zones), Novotukalandian (Irvingella norilica, Tukalandaspis egens, Ketyna ketiensis – Monosulcatina laeve zones) and Khantaian (Dolgeuloma abunda – Dolgeuloma dolganensis, Loparella loparica – Plethopeltides magnus zones). The boundary between the Cambrian and Ordovician is fixed at the Nyayskiy Horizon bottom where Eoapatokephalus antiquus Rosova et Makarova trilobite species appear. All the stratotypes are characterized by isotopic data. Matching of General stratigraphic chart of Cambrian with International stratigraphic chart is conducted.
Aleksei I. Varlamov Scopus
Doctor of Geological and Mineralogical Sciences,
Academic Director
All-Russian Research
Geological Oil Institute,
36, Shosse Entuziastov, Moscow, 105118, Russia
e-mail: varlamov.geo@gmail.com
Aleksei Yu. Rozanov
Doctor of Geological and Mineralogical Sciences,
Academician, advisor of RAS,
Professor, Head of Laboratory
Russian Academy of Sciences,
14, Leninsky Prospect, Moscow, 119991, Russia
e-mail: aroza@paleo.ru
Anastasiya L. Makarova
Researcher
Novosibirsk Branch
of All-Russian Research
Geological Oil Institute,
17/1 ul. Oktyabr’skaya, Novosibirsk, 630099, Russia
e-mail: Makarova@vnigni.ru
SPIN-код: 8020-3712,
AuthorID: 1226946
Dmitry A. Komlev Scopus
Head of Group
Novosibirsk Branch
of All-Russian Research
Geological Oil Institute,
17/1 ul. Oktyabr’skaya, Novosibirsk, 630099, Russia
e-mail: komlev@vnigni.ru
Sergei S. Sukhov
Candidate of Geological and Mineralogical Sciences,
Head of Laboratory
Siberian Research Institute of Geology, Geophysics and Mineral
Raw Materials,
67, prospect Krasnyi, Novosibirsk, 630091, Russia
e-mail: sukhov@sniiggims.ru
SPIN-код: 7454-5250
AuthorID: 59295
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