TY - JOUR

T1 - Bio-, Lithostratigraphic and Geochemical Markers of Global Events in the Upper Devonian of the South of Western Siberia and their Value for Inter-regional Correlations

AU - Izokh, O. P.

AU - Izokh, N. G.

AU - Popov, B. M.

AU - Saraev, S. V.

N1 - The authors are sincerely grateful to A.S. Alekseev and O.V. Artyushkova for constructive comments and advice that contributed towards the improvement of the article. The article was prepared with the support of the Russian Science Foundation project 22-27-00703, as well as with the scientific and methodological support of the State Program of the Federal Research Institute of the Russian Academy of Sciences Nos. FWZZ-2022-0003, FWZZ-2022-0005, and FWZZ-2022-0007.

PY - 2024/8/1

Y1 - 2024/8/1

N2 - Upper Devonian carbonate reef complexes have been studied on the territory of the Kolyvan-Tom’ Folded Area in sections in the right bank of Tom’ River. Facies analysis of the exposed part of the reef complex indicates the predominance of fore-reef and continental margin depositional environments of a tectonically active margin. The identified conodont associations are represented by cosmopolitan representatives of the genera Ancyrodella, Ancyrolepis, Icriodus, Mehlina, Palmatolepis, Polygnathus and “Polylophodonta” suggesting a correlation with the punctata–jamieae, rhenana–linguiformis, triangularis and Lower crepida conodont zones. The largest conodont diversity occurs at the triangularis/crepida boundary. Biofacies analysis of ostracod distribution has led to identification of characteristic associations and their restriction to certain parts of the palaeobasin. Substage boundaries yielded ostracods with both smooth and ornamented shells. In the lower part of the substages, smooth forms predominate, whereas the middle and upper parts of the substages are characterised by forms with tuberculate and reticulated surface. Hollinella valentinae Beds were traced in the Upper Frasnian Solomino Formation, and Acratia granuliformis Beds were traced in the Lower Famennian Kosoy Utyos and lower Mitikha members. Isotope geochemistry of the Upper Devonian sections of the south of Western Siberia reveals Frasnian global events – the Middlesex/punctata and the Upper Kellwasser, their stratigraphic position confirmed by palaeontological data, as well as by the globally expressed negative carbon isotope anomaly. These boundaries are marked by changes in depositional regime reflecting sea-level eustatic fluctuations, which are complemented with faunal changes.

AB - Upper Devonian carbonate reef complexes have been studied on the territory of the Kolyvan-Tom’ Folded Area in sections in the right bank of Tom’ River. Facies analysis of the exposed part of the reef complex indicates the predominance of fore-reef and continental margin depositional environments of a tectonically active margin. The identified conodont associations are represented by cosmopolitan representatives of the genera Ancyrodella, Ancyrolepis, Icriodus, Mehlina, Palmatolepis, Polygnathus and “Polylophodonta” suggesting a correlation with the punctata–jamieae, rhenana–linguiformis, triangularis and Lower crepida conodont zones. The largest conodont diversity occurs at the triangularis/crepida boundary. Biofacies analysis of ostracod distribution has led to identification of characteristic associations and their restriction to certain parts of the palaeobasin. Substage boundaries yielded ostracods with both smooth and ornamented shells. In the lower part of the substages, smooth forms predominate, whereas the middle and upper parts of the substages are characterised by forms with tuberculate and reticulated surface. Hollinella valentinae Beds were traced in the Upper Frasnian Solomino Formation, and Acratia granuliformis Beds were traced in the Lower Famennian Kosoy Utyos and lower Mitikha members. Isotope geochemistry of the Upper Devonian sections of the south of Western Siberia reveals Frasnian global events – the Middlesex/punctata and the Upper Kellwasser, their stratigraphic position confirmed by palaeontological data, as well as by the globally expressed negative carbon isotope anomaly. These boundaries are marked by changes in depositional regime reflecting sea-level eustatic fluctuations, which are complemented with faunal changes.

KW - Frasnian and Famennian stages

KW - Western Siberia

KW - carbon

KW - carbonates

KW - conodonts

KW - events

KW - isotopes

KW - lithology of carbonate deposits

KW - ostracods

KW - oxygen

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85202042357&origin=inward&txGid=2043ff2e26f06a3c0fe006acca60b906

UR - https://www.mendeley.com/catalogue/f6652851-466d-3714-b367-dc40db45ee9a/

U2 - 10.2113/RGG20244634

DO - 10.2113/RGG20244634

M3 - Article

VL - 65

SP - 977

EP - 999

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 8

ER -