Capitanian

In the geologic timescale, the Capitanian is an age or stage of the Permian. It is also the uppermost or latest of three subdivisions of the Guadalupian Epoch or Series. The Capitanian lasted between 264.28 and 259.51 million years ago. It was preceded by the Wordian and followed by the Wuchiapingian.[4]

Capitanian
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 definitionFAD of the Conodont Jinogondolella postserrata
Lower boundary GSSPNipple Hill, Guadalupe Mountains, Texas, USA
31.9091°N 104.7892°W / 31.9091; -104.7892
Lower GSSP ratified2001[2]
Upper boundary definitionFAD of the Conodont Clarkina postbitteri postbitteri
Upper boundary GSSPPenglaitan Section, Laibin, Guangxi, China
23.6953°N 109.3211°E / 23.6953; 109.3211
Upper GSSP ratified2004[3]

A significant mass extinction event occurred at the end of this stage, which was associated with anoxia and acidification in the oceans and possibly caused by the volcanic eruptions that produced the Emeishan Traps.[5] This extinction event may be related to the much larger Permian–Triassic extinction event that followed about 10 million years later.

Stratigraphy

The Capitanian Stage was introduced into scientific literature by George Burr Richardson in 1904. The name comes from the Capitan Reef in the Guadalupe Mountains (Texas, United States). The Capitanian was first used as a stratigraphic subdivision of the Guadalupian in 1961,[6] when both names were still only used regionally in the southern US. The stage was added to the internationally used ICS timescale in 2001.[7]

Definitions

The base of the Capitanian Stage is defined as the place in the stratigraphic record where fossils of conodont species Jinogondolella postserrata first appear. The global reference profile for this stratigraphic boundary is located at Nipple Hill in the southern Guadalupe Mountains of Texas.

The top of the Capitanian (the base of the Wuchiapingian and Lopingian series) is defined as the place in the stratigraphic record where the conodont species Clarkina postbitteri postbitteri first appears.

The Capitanian Stage was part of the time in which the Zechstein was deposited in Europe.[4] It is coeval with the old European regional Saxonian Stage. In the eastern Tethys domain, the Capitanian overlaps the regional Murgabian Stage, the Midian Stage and the lower part of the Laibinian Stage. In Russia the Capitanian equals the lower part of the regional Severodvinian Stage.

Biostratigraphy

The Capitanian contains one ammonite biozone (Timorites) and three conodont biozones:

  • zone of Clarkina postbitteri hongshuiensis
  • zone of Jinogondolella altudaensis
  • zone of Jinogondolella postserrata

Larger fusulinid species permit a division in two biozones:

  • zone of Rausserella
  • zone of Afganella schenki

Biodiversity

Olson’s Extinction, in the early Guadalupian (Roadian, Wordian), led to an extended period of low diversity when worldwide two-thirds of terrestrial vertebrate life was lost.[8] Global diversity rose dramatically in the Capitanian, probably the result of disaster taxa filling empty guilds, only to fall again when the end-Guadalupian event caused a diversity drop in the Wuchiapingian.[9]

Events

Carbon isotopes in marine limestone from the Capitanian age show an increase in δ13C values. The change in carbon isotopes in the sea water reflects cooling of global climates.[10]

This climatic cooling may have caused the end-Capitanian extinction event among species that lived in warm water, like larger fusulinids (Verbeekninidae), large bivalves (Alatoconchidae) and rugose corals, and Waagenophyllidae.[11]

References
  1. "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  2. "GSSP for Roadian Stage". International Commission on Stratigraphy. Retrieved 13 December 2020.
  3. Jin, Yugan; Shen, Shuzhong; Henderson, Charles; Wang, Xiangdong; Wang, Wei; Wang, Yue; Cao, Changqun; Shang, Qinghua (December 2006). "The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian Stage (Permian)" (PDF). Episodes. 29 (4): 253–262. doi:10.18814/epiiugs/2006/v29i4/003. Retrieved 13 December 2020.
  4. Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press
  5. Bond, D. P. G.; Wignall, P. B.; Joachimski, M. M.; Sun, Y.; Savov, I.; Grasby, S. E.; Beauchamp, B.; Blomeier, D. P. G. (2015-04-14). "An abrupt extinction in the Middle Permian (Capitanian) of the Boreal Realm (Spitsbergen) and its link to anoxia and acidification" (PDF). Geological Society of America Bulletin. 127 (9–10): 1411–1421. Bibcode:2015GSAB..127.1411B. doi:10.1130/B31216.1. ISSN 0016-7606.
  6. Glenister, B.F. & Furnish, W.M.; 1961: The Permian ammonoids of Australia, Journal of Paleontology 35(4), pp 673–736.
  7. Glenister, B.F.; Wardlaw, B.R.; Lambert, L.L.; Spinosa, C.; Bowring, S.A.; Erwin, D.H.; Menning, M. & Wilde, G.L.; 1999: Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Stages as International Standards for the Middle Permian Series, Permophiles 34: pp 3–11.
  8. Bond, David; Hilton, Jason (2010). "The Middle Permian (Capitanian) mass extinction on land and in the oceans". Earth-Science Reviews. 102 (1): 100–116. Bibcode:2010ESRv..102..100B. doi:10.1016/j.earscirev.2010.07.004.
  9. Sahney, S.; Benton, M.J. (2008). "Recovery from the most profound mass extinction of all time". Proceedings of the Royal Society B: Biological Sciences. 275 (1636): 759–65. doi:10.1098/rspb.2007.1370. PMC 2596898. PMID 18198148.
  10. Isozaki, Yukio; Kawahata, Hodaka; Ota, Ayano (2007). "A unique carbon isotope record across the Guadalupian–Lopingian (Middle–Upper Permian) boundary in mid-oceanic paleo-atoll carbonates: The high-productivity "Kamura event" and its collapse in Panthalassa". Global and Planetary Change. 55 (1–3): 21–38. Bibcode:2007GPC....55...21I. doi:10.1016/j.gloplacha.2006.06.006.
  11. Isozaki, Yukio; Aljinović, Dunja (2009). "End-Guadalupian extinction of the Permian gigantic bivalve Alatoconchidae: End of gigantism in tropical seas by cooling". Palaeogeography, Palaeoclimatology, Palaeoecology. 284 (1–2): 11–21. Bibcode:2009PPP...284...11I. doi:10.1016/j.palaeo.2009.08.022. ISSN 0031-0182.

31.9091°N 104.7892°W / 31.9091; -104.7892

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