TheKasimovianis ageochronologicageorchronostratigraphicstagein theICSgeologic timescale.It is the third stage in thePennsylvanian(lateCarboniferous), lasting from 307 to 303.7Ma.[3]The Kasimovian Stage follows theMoscovianand is followed by theGzhelian. The Kasimovian saw an extinction event which occurred around 305 mya, referred to as theCarboniferous Rainforest Collapse.[4]It roughly corresponds to theMissourianin North American geochronology and theStephanianin western European geochronology.

Kasimovian
307.0 ± 0.1 – 303.7 ± 0.1Ma
Chronology
Etymology
Name formalityFormal
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
Time span formalityFormal
Lower boundary definitionNot formally defined
Lower boundary definition candidatesFADof theFusulinidProtriticitesor 1 million years olderMontiparus montiparus[2]
Lower boundary GSSP candidate section(s)
Upper boundary definitionNot formally defined
Upper boundary definition candidatesFAD of theConodontIdiognathodus simulator[2]
Upper boundary GSSP candidate section(s)
  • Southern Ural mountains[2]
  • Nashui, Luodian County, Guizhou, China

Name and definition

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The Kasimovian is named after theRussiancity ofKasimov.The stage was split from the Moscovian in 1926 by Boris Dan'shin (1891-1941), who gave it the nameTeguliferina horizon.The name was posthumously changed toKasimov horizonby Dan'shin in 1947. The name Kasimovian was introduced by Georgy Teodorovich in 1949.

The base of the Kasimovian Stage is at the base of thefusulinidbiozoneofObsoletes obsoletesandProtriticites pseudomontiparusor with the first appearance of theammonitegenusParashumardites.The top of the stage is close to the first appearances of the fusulinid generaDaixina,JigulitesandRugosofusulinaor the first appearance of the conodontStreptognathodus zethus.

Biozones

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The Kasimovian is subdivided into three conodontbiozones:

  • IdiognathodustoretzianusZone
  • Idiognathodus sagittatusZone
  • Streptognathodus excelsusandStreptognathodus makhlinaeZone

References

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  1. ^"International Chronostratigraphic Chart"(PDF).International Commission on Stratigraphy.September 2023.RetrievedNovember 10,2024.
  2. ^abcd"Global Boundary Stratotype Section and Point".International Commission of Stratigraphy.Retrieved23 December2020.
  3. ^Gradstein, F.M.; Ogg, J.G. & Smith, A.G.;2004:A Geologic Time Scale 2004,Cambridge UniversityPress.
  4. ^Sahney, S., Benton, M.J. & Falcon-Lang, H.J. (2010)."Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica"(PDF).Geology.38(12): 1079–1082.Bibcode:2010Geo....38.1079S.doi:10.1130/G31182.1.{{cite journal}}:CS1 maint: multiple names: authors list (link)

Literature

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  • Dan'shin, V.M.;1947:Geology and Mineral Resources of Moscow and its Surroundings,Izdat. Moskov. Obshch. Isp. Prir., Moscow, 308 pp.(in Russian).
  • Menning, M.; Alekseev, A.S.; Chuvashov, B.I.; Davydov, V.I.; Devuyst, F.-X.; Forke, H.C.; Grunt, T.A.; Hance, L.; Heckel, P.H.; Izokh, N.G.; Jin, Y.-G.; Jones, P.J.; Kotlyar, G.V.; Kozur, H.W.; Nemyrovska, T.I.; Schneider, J.W.; Wang, X.-D.; Weddige, K.; Weyer, D. & Work, D.M.;2006:Global time scale and regional stratigraphic reference scales of Central and West Europe, East Europe, Tethys, South China, and North America as used in the Devonian–Carboniferous–Permian Correlation Chart 2003 (DCP 2003),Palaeogeography, Palaeoclimatology, Palaeoecology240(1-2): pp 318–372.
  • Teodorovich, Georgy I. (1949).О подразделении верхнего карбона на ярусы[On the subdivision of the Upper Carboniferous into stages].Doklady Akademii Nauk SSSR(in Russian).67(3): 537–540.
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