Cisuralian

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Cisuralian
298.9 ± 0.15 – 273.01 ± 0.14 Ma
morphotype Streptognathodus wabaunsensis chronocline
Lower boundary GSSPAidaralash, Ural Mountains, Kazakhstan
50°14′45″N 57°53′29″E / 50.2458°N 57.8914°E / 50.2458; 57.8914
Lower GSSP ratified1996[2]
Upper boundary definitionFAD of the Conodont Jinogondolella nanginkensis
Upper boundary GSSPStratotype Canyon, Guadalupe Mountains, Texas, U.S.A.
31°52′36″N 104°52′36″W / 31.8767°N 104.8768°W / 31.8767; -104.8768
Upper GSSP ratified2001[3]

The Cisuralian is the first

epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the western slopes of the Ural Mountains in Russia and Kazakhstan and dates between 298.9 ± 0.15 – 272.3 ± 0.5 Mya.[4]

The Cisuralian is often synonymous with the informal terms early Permian or lower Permian. It corresponds approximately with the Wolfcampian in southwestern North America.[5][6]

The series saw the appearance of beetles and flies and was a relatively stable warming period of about 21 million years.

Name and background

The Cisuralian is the first series or epoch of the Permian.[7] The Cisuralian was preceded by the last Pennsylvanian epoch (Gzhelian) and is followed by the Permian Guadalupian Epoch.

The name "Cisuralian" was proposed in 1982,[8] and approved by the International Subcommission on Permian Stratigraphy in 1996.[9] The Cisuralian Epoch is named after the western slopes of the Ural Mountains in Russia and Kazakhstan.[10][11][12]

Limestones on the edge of

Russian Platform and make up the Ishimbay oil fields. These oil fields were vital to the Soviet Union during WW2 when the Germans controlled the oil fields to the west.[10]

The International Chronostratigraphic Chart (v2018/07)[7] provides a numerical age of 298.9 ± 0.15 – 272.3 ± 0.5 Mya.[13]

The base of the Cisuralian series and the Permian

Aqtöbe in the Ural Mountains of Kazakhstan.[14]

Geography

Pangea, by the middle of the early Permian, which was to have an impact on the climate.[10]

Climate

Selwyn Rock, South Australia, an exhumed glacial pavement
of Permian age

At the start of the Permian, the Late Palaeozoic Ice Age, which began in the Carboniferous, was at its peak. Glaciers receded over the course of the late Cisuralian as the Earth's climate gradually warmed, particularly during the Artinskian Warming Event,[15] drying the continent's interiors.[16][17][18] The pan-tropical belt of Pangaea experienced particularly significant aridification during this epoch.[19][20][21]

Biodiversity

The swampy fringes were mostly ferns, seed ferns, and

lycophytes. The series saw the appearance of beetles and flies.[10]

The coal swamps from the

Caseids and prototherapsid Tetraceratops made their appearance.[11] The marine life was probable more diverse than modern times as the climate warmed.[10] Unusual sharks such as Helicoprion
continued in this series.

Early Permian terrestrial faunas were dominated by pelycosaurs, diadectids, and amphibians,[22][23] The pelycosaurs appeared during the Late Carboniferous, and reached their apex in the Cisuralian remaining the dominant land animals for some 40 million years.[11] A few continued into the Capitanian. They were succeeded by the therapsids.[11]

Subdivisions

Global

  • Asselian stage (298.9 ± 0.15 – 294.6 ± 0.8 Mya)
  • Sakmarian stage (294.6 ± 0.8 – 290.1 ± 0.7 Mya)
  • Artinskian stage (290.1 ± 0.7 – 283.5 ± 0.7 Mya)
  • Kungurian stage (283.5 ± 0.7 – 272.3 ± 0.5 Mya)

Regional

  • New Zealand
    • Telfordian (289 – 278 Mya)
    • Mangapirian (278 – 270.6 Mya)

References

  1. ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  2. doi:10.18814/epiiugs/1998/v21i1/003
    . Retrieved 7 December 2020.
  3. ^ "GSSP for Roadian Stage". International Commission on Stratigraphy. International Commission on Stratigraphy. Retrieved 13 December 2020.
  4. ISBN 9780521786737
    .
  5. ISBN 978-3-642-78595-5
    .
  6. ^ "Permian: Stratigraphy". UC Museum of Paleontology. University of California Berkeley. Retrieved 17 June 2021.
  7. ^ a b International Commission on Stratigraphy. "Chart". Retrieved 10 July 2018.
  8. ISBN 978-0-521-78673-7
    .
  9. ^ Ganelin, V.G.; Goman'kov, A.V.; Grunt, T.A.; Durante, M.V. (January 1997). "On the revised stratigraphic scale for the Permian System adopted at the Second Guadalupian Symposium, alpine, Texas, USA, April 1996". Stratigraphy and Geological Correlation. 5 (2): 126–130.
  10. ^ a b c d e f g Ross, June R.P.; Ross, Charles A. (16 October 2018). "Permian Period". Encyclopædia Britannica. Retrieved 18 April 2019.
  11. ^ a b c d e Kazlev, M. Alan (4 May 2002). "The Cisuralian Epoch". palaeos.com. Retrieved 18 April 2019.
  12. ISBN 9780199653065
    .
  13. ^ International Commission on Stratigraphy. "GSSPs". Retrieved 10 July 2018.
  14. ^ Davydov, V.I.; Glenister, B.F.; Spinosa, C.; Ritter, S.M.; Chernykh, V.V.; Wardlaw, B.R. and Snyder, W.S.; 1998: Proposal of Aidaralash as Global Stratotype Section and Point (GSSP) for base of the Permian System, Episodes 21(1): pp 11–18.
  15. S2CID 245892961
    . Retrieved 30 October 2022.
  16. doi:10.1016/j.palaeo.2015.03.020
    .
  17. ^ Palaeos: Life Through Deep Time > The Permian Period Archived 2013-06-29 at the Wayback Machine Accessed 1 April 2013.
  18. doi:10.1016/j.palaeo.2008.03.053
    . Retrieved 30 October 2022.
  19. doi:10.1016/j.palaeo.2018.01.012
    . Retrieved 22 December 2022.
  20. S2CID 133713470
    . Retrieved 22 December 2022.
  21. S2CID 246438404
    . Retrieved 3 January 2023.
  22. ^ Huttenlocker, A. K., and E. Rega. 2012. The Paleobiology and Bone Microstructure of Pelycosaurian-grade Synapsids. Pp. 90–119 in A. Chinsamy (ed.) Forerunners of Mammals: Radiation, Histology, Biology. Indiana University Press.
  23. ^ "NAPC Abstracts, Sto – Tw". berkeley.edu.
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