THE REGIONAL STRATIGRAPHIC CHART OF THE ORDOVICIAN OF THE SIBERIAN PLATFORM (NEW VERSION)

A. V. Kanygin1,3, A. G. Yadrenkina2, A. V. Timokhin1, T. A. Moskalenko1, T. V. Gonta1, N. I. Stepanova4, O. V. Sychev2, O. A. Maslova2

1 Trofimuk Institute of Petroleum Geology and Geophysics of Siberian Branch of Russian Academy of Sciences (IPGG SB RAS), Novosibirsk

2 Siberian Research Institute of Geology, Geophysics and Mineral Resources (SNIIGGiMS), Novosibirsk

3 Novosibirsk National State Research University, Novosibirsk

4 Irkutskgeofizika, Irkutsk

A new version of the Regional Stratigraphic Chart of the Ordovician of the Siberian Platform and an explanatory note thereto, compiled in accordance with the requirements of the Stratigraphic Code of Russia, reflect updates of, supplements to, and changes in the previous chart accepted at the Interdepartmental Meeting on Stratigraphy in Novosibirsk in 1979 and then approved by the Interdepartmental Stratigraphic Committee of the USSR as an official basis of geological and geophysical exploration within the territory. Since then, the International Stratigraphic Chart of the Ordovician System has significantly changed: instead of the former stage-based division of the system, based on a sequence of formations within Britain, the International Commission on Stratigraphy decided on the new division of the system into series and stages, stratotypes of which are located in different continents. A new category of stratigraphic standards—stratigraphic boundary stratotype, or limitotype—was introduced as the main geochronological marker of the stratigraphic chart division. These limitotypes are referred to as the key references in global stratigraphic correlations, instead of the former stratotypes. This required fundamental revision of the correlation of regional stratigraphic subdivisions with global stratigraphic standards, both division into series and stages and change in the system boundaries.

Key words: Siberian Platform, Ordovician, Regional stratigraphic chart, explanatory note.

DOI 10.20403/2078-0575-2016-5s-4-57