- Moscovian (Carboniferous)
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System Subsystem/
SeriesStage Age
(Ma)Permian Cisuralian Asselian younger Carboniferous Pennsylvanian Gzhelian 299.0–303.9 Kasimovian 303.9–306.5 Moscovian 306.5–311.7 Bashkirian 311.7–318.1 Mississippian Serpukhovian 318.1–328.3 Viséan 328.3–345.3 Tournaisian 345.3–359.2 Devonian Upper Famennian older Subdivision of the Carboniferous system according to the ICS.[1] The Moscovian is in the ICS geologic timescale a stage or age in the Pennsylvanian, the youngest subsystem of the Carboniferous. The Moscovian age lasted from 311.7 ± 1.1 to 306.5 ± 1.0 Ma,[2] is preceded by the Bashkirian and is followed by the Kasimovian. The Moscovian overlaps with the European regional Westphalian stage and the North American Atokan and Desmoinesian stages.
The Moscovian saw an extinction event which occurred on the land and the sea. On the land it is referred to as the Carboniferous Rainforest Collapse.[3]
Contents
Name and definition
The Moscovian stage was introduced by Sergei Nikitin (1850 - 1909) in 1890, using brachiopods in the Moscow Basin of European Russia. Nikitin named the stage after Moscow, then a major city and now the capital of Russia.
The base of the Moscovian is close to the first appearances of the conodonts Declinognathodus donetzianus and Idiognathoides postsulcatus[4] or otherwise the fusulinid Aljutovella aljutovica.[5] Because the fusulinid species are regionally different, they can not be used for worldwide correlation. A golden spike for the Moscovian stage has yet to be defined (2008). A proposal is to use the first appearance of the conodont Diplognathodus ellesmerensis, but since the species is rare and its evolution relatively unknown, it has not been accepted yet.[6]
The top of the Moscovian (base of the Kasimovian) is at the base of the fusulinid biozone of Obsoletes obsoletes and Protriticites pseudomontiparus, or with the first appearance of the ammonite genus Parashumardites.
Subdivisions
In European Russia and Eastern Europe, where the stage was first recognized, the Moscovian is subdivided into four regional substages: Vereiskian, Kashirskian, Podolskian, and Myachkovskian.
The Moscovian can biostratigraphically be divided into five conodont biozones:
- Neognathodus roundyi and Streptognathodus cancellosus Zone
- Neognathodus medexultimus and Streptognathodus concinnus Zone
- Streptognathodus dissectus Zone
- Neognathodus uralicus Zone
- Declinognathodus donetzianus Zone
References
- ^ Gradstein et al. (2004)
- ^ Gradstein et al. (2004)
- ^ Sahney, S., Benton, M.J. & Falcon-Lang, H.J. (2010). "Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica" (PDF). Geology 38 (12): 1079–1082. doi:10.1130/G31182.1. http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079.
- ^ Nemyrovska (1999)
- ^ For example by Solovieva (1986)
- ^ See this report by the taskforce to establish a Bashkirian-Moscovian boundary (Groves et al. (2008))
Literature
- Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press
- Nemyrovska, T.I.; 1999: Bashkirian conodonts of the Donets Basin, Ukraine. Scr. Geol. 119, pp 1–115 (Russian).
- Nikitin, S.N.; 1890: Carboniferous deposits of the Moscow region and artesian waters near Moscow, Trudy Geologicheskogo Komiteta 5(5), pp. 1–182 (Russian).
- Solovieva, M.N.; 1986: Zonal fusulinid scale of the Moscovian Stage based on a revision of the type sections of intrastage subdivisions, Vopr. Mikropaleontol. 28, pp 3–23 (Russian).
External links
- Carboniferous timescale at the website of the Norwegian network of offshore records of geology and stratigraphy
- Moscovian, Geowhen Database
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