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Ypresian

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Ypresian
56.0 – 47.8Ma
Earth ~50 mya
Klondike Mountain Formation,Republic, Washington
Chronology
Formerly part ofTertiaryPeriod/System
Etymology
Name formalityFormal
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
First proposed byDumont
Time span formalityFormal
Lower boundary definitionStrong negative anomaly inδ13Cvalues at thePETM[3]
Lower boundary GSSPDababiya section,Luxor,Egypt[3]
25°30′00″N32°31′52″E/ 25.5000°N 32.5311°E/25.5000; 32.5311
Lower GSSP ratified2003[3]
Upper boundary definitionFADof the calcareous nannofossilBlackites inflatus
Upper boundary GSSPGorrondatxe section,Western Pyrenees,Basque Country,Spain
43°22′47″N3°00′51″W/ 43.3796°N 3.0143°W/43.3796; -3.0143
Upper GSSP ratifiedApril 2011[4]

In thegeologic timescaletheYpresianis the oldestageor loweststratigraphic stageof theEocene.It spans the time between56and47.8Ma,is preceded by theThanetianAge (part of thePaleocene) and is followed by the EoceneLutetianAge. The Ypresian is consistent with the Lower Eocene (Early Eocene).

Events

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See also:Cambay Shale Formation,pCO2,andδ18O

The Ypresian Age begins during the throes of thePaleocene–Eocene Thermal Maximum(PETM). TheFur FormationinDenmark,theMessel shalesinGermany,theOise amberof France andCambay amberof India are of this age. TheEocene Okanagan Highlandsare an uplands subtropical to temperate series of lakes from the Ypresian.[5][6][7]

The Ypresian is additionally marked by another warming event called the Early Eocene Climatic Optimum (EECO). The EECO is the longest sustained warming event in the Cenozoic record, lasting about 2–3 million years between 53 and 50 Ma. The interval is characterized by lowoxygen-18isotopes,[8][9][10]high levels ofatmospheric pCO2,[11][12]and low meridional thermal gradients.[13]Biodiversityhas been reported to have been significantly impacted by the conditions prevalent during the EECO. For instance, there were biotic turnovers amongmarine producerssuch ascalcareous nannofossilsamong others etc.[14][15]

Stratigraphic definition

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See also:List of geochronologic names

The Ypresian Stage was introduced in scientific literature byBelgiangeologistAndré Hubert Dumontin 1850. The Ypresian is named after theFlemishcity ofYpresin Belgium (spelledIeperin Dutch). The definitions of the original stage were totally different from the modern ones.[16]The Ypresian shares its name with the BelgianIeper Group(French:Groupe d'Ypres), which has an Ypresian age.

The base of the Ypresian Stage is defined at a strong negative anomaly inδ13Cvalues at thePETM.The official reference profile (GSSP) for the base of the Ypresian is the Dababiya profile near theEgyptiancity ofLuxor.[17]Its originaltype sectionwas located in the vicinity of Ieper.

The top of the Ypresian (the base of the Lutetian) is identified by the first appearance of theforaminiferagenusHantkeninain the fossil record.

The Ypresian Stage overlaps the upper Neustrian and most of the GrauvianEuropean Land Mammal Mega Zones(it spans theMammal Paleogene zones7 through 10.[18]), theWasatchianand lower and middleBridgerianNorth American Land Mammal Ages,theCasamayoranSouth American Land Mammal Ageand theBumbanianand most of theArshantanAsian Land Mammal Ages.It is also coeval with the upper Wangerripian and lowest Johannian regional stages ofAustraliaand the Bulitian, Penutian, and Ulatisian regional stages ofCalifornia.

References

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  1. ^Zachos, J. C.; Kump, L. R. (2005). "Carbon cycle feedbacks and the initiation of Antarctic glaciation in the earliest Oligocene".Global and Planetary Change.47(1): 51–66.Bibcode:2005GPC....47...51Z.doi:10.1016/j.gloplacha.2005.01.001.
  2. ^"International Chronostratigraphic Chart"(PDF).International Commission on Stratigraphy.
  3. ^abcAubry, Marie-Pierre; Ouda, Khaled; Dupuis, Christian; William A. Berggren; John A. Van Couvering; Working Group on the Paleocene/Eocene Boundary (2007)."The Global Standard Stratotype-section and Point (GSSP) for the base of the Eocene Series in the Dababiya section (Egypt)"(PDF).Episodes.30(4): 271–286.doi:10.18814/epiiugs/2007/v30i4/003.
  4. ^Molina, Eustoquio; Alegret, Laia; Apellaniz, Estibaliz; Bernaola, Gilen; Caballero, Fernando; Jaume Dinarès-Turell; Hardenbol, Jan; Claus Heilmann-Clausen; Juan C. Larrasoana; Hanspeter Luterbacher; Simonetta Monechi; Silvia Ortiz; Xabier Orue-Etxebarria; Aitor Payros; Victoriano Pujalte; Francisco J. Rodríguez-Tobar; Flavia Tori; Josep Tosquella; Alfred Uchman (2011)."The Global Stratotype Section and Point (GSSP) for the base of the Lutetian Stage at the Gorrondatxe section, Spain"(PDF).Episodes.34(2): 86–108.doi:10.18814/epiiugs/2011/v34i2/006.
  5. ^Greenwood, D.R.; Archibald, S.B.; Mathewes, R.W; Moss, P.T. (2005). "Fossil biotas from the Okanagan Highlands, southern British Columbia and northeastern Washington State: climates and ecosystems across an Eocene landscape".Canadian Journal of Earth Sciences.42(2): 167–185.Bibcode:2005CaJES..42..167G.doi:10.1139/e04-100.
  6. ^Archibald, S.; Greenwood, D.; Smith, R.; Mathewes, R.; Basinger, J. (2011). "Great CanadianLagerstätten1. Early Eocene Lagerstätten of the Okanagan Highlands (British Columbia and Washington State) ".Geoscience Canada.38(4): 155–164.
  7. ^Lowe, A. J.; Greenwood, D. R.; West, C. K.; Galloway, J. M.; Sudermann, M.; Reichgelt, T. (2018). "Plant community ecology and climate on an upland volcanic landscape during the Early Eocene Climatic Optimum: McAbee Fossil Beds, British Columbia, Canada".Palaeogeography, Palaeoclimatology, Palaeoecology.511:433–448.Bibcode:2018PPP...511..433L.doi:10.1016/j.palaeo.2018.09.010.S2CID134962126.
  8. ^Bijl, Peter K.; Schouten, Stefan; Sluijs, Appy; Reichart, Gert-Jan; Zachos, James C.; Brinkhuis, Henk (October 2009)."Early Palaeogene temperature evolution of the southwest Pacific Ocean".Nature.461(7265): 776–779.Bibcode:2009Natur.461..776B.doi:10.1038/nature08399.hdl:1874/385779.ISSN1476-4687.PMID19812670.S2CID4358350.
  9. ^Hollis, Christopher J.; Handley, Luke; Crouch, Erica M.; Morgans, Hugh E.G.; Baker, Joel A.; Creech, John; Collins, Katie S.; Gibbs, Samantha J.; Huber, Matthew; Schouten, Stefan; Zachos, James C.; Pancost, Richard D. (2009-02-01)."Tropical sea temperatures in the high-latitude South Pacific during the Eocene".Geology.37(2): 99–102.Bibcode:2009Geo....37...99H.doi:10.1130/g25200a.1.ISSN1943-2682.
  10. ^Zachos, James; Pagani, Mark; Sloan, Lisa; Thomas, Ellen; Billups, Katharina (2001-04-27)."Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present".Science.292(5517): 686–693.Bibcode:2001Sci...292..686Z.doi:10.1126/science.1059412.ISSN0036-8075.PMID11326091.
  11. ^Beerling, David J.; Royer, Dana L. (July 2011)."Convergent Cenozoic CO2 history".Nature Geoscience.4(7): 418–420.Bibcode:2011NatGe...4..418B.doi:10.1038/ngeo1186.ISSN1752-0908.
  12. ^Zachos, James C.; Dickens, Gerald R.; Zeebe, Richard E. (January 2008)."An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics".Nature.451(7176): 279–283.Bibcode:2008Natur.451..279Z.doi:10.1038/nature06588.ISSN1476-4687.PMID18202643.S2CID4360841.
  13. ^Cramwinckel, Margot J.; Huber, Matthew; Kocken, Ilja J.; Agnini, Claudia; Bijl, Peter K.; Bohaty, Steven M.; Frieling, Joost; Goldner, Aaron; Hilgen, Frederik J.; Kip, Elizabeth L.; Peterse, Francien; van der Ploeg, Robin; Röhl, Ursula; Schouten, Stefan; Sluijs, Appy (July 2018)."Synchronous tropical and polar temperature evolution in the Eocene".Nature.559(7714): 382–386.Bibcode:2018Natur.559..382C.doi:10.1038/s41586-018-0272-2.hdl:1874/366626.ISSN1476-4687.PMID29967546.S2CID256767465.
  14. ^Cappelli, C.; Bown, P. R.; Westerhold, T.; Bohaty, S. M.; Riu, M.; Lobba, V.; Yamamoto, Y.; Agnini, C. (December 2019)."The Early to Middle Eocene Transition: An Integrated Calcareous Nannofossil and Stable Isotope Record From the Northwest Atlantic Ocean (Integrated Ocean Drilling Program Site U1410)".Paleoceanography and Paleoclimatology.34(12): 1913–1930.Bibcode:2019PaPa...34.1913C.doi:10.1029/2019PA003686.hdl:11577/3322441.ISSN2572-4517.S2CID210245165.
  15. ^Schneider, Leah J.; Bralower, Timothy J.; Kump, Lee R. (October 2011)."Response of nannoplankton to early Eocene ocean destratification".Palaeogeography, Palaeoclimatology, Palaeoecology.310(3–4): 152–162.Bibcode:2011PPP...310..152S.doi:10.1016/j.palaeo.2011.06.018.
  16. ^Steurbaut (2006)
  17. ^The GSSP was established by Dupuiset al.(2003)
  18. ^Alroy, John."Mammal Paleogene zones".p. The Paleobiology Database.Retrieved15 July2009.

Literature

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Wikisource has original works on the topic:Cenozoic#Paleogene
  • Dumont, A. H.;1850:Rapport sur la carte géologique du Royaume,Bulletins de l’Académie Royale des Sciences, des Lettres et des Beaux-Arts de Belgique16(2), pp. 351–373.(in French)
  • Dupuis, C.; Aubry, M.; Steurbaut, É; Berggren, W. A.; Ouda, K.; Magioncalda, R.; Cramer, B. S.; Kent, D. V.; Speijer, R. P. & Heilmann-Clausen, C.; 2003:The Dababiya Quarry Section: Lithostratigraphy, clay mineralogy, geochemistry and paleontology,Micropaleontology49(1), pp. 41–59,ISSN0026-2803.
  • Gradstein, F. M.; Ogg, J. G. & Smith, A. G.; 2004:A Geologic Time Scale 2004,Cambridge University Press.
  • Steurbaut, É.; 2006:YpresianArchived2012-02-18 at theWayback Machine,Geologica Belgica9(1–2), pp. 73–93.
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