View source for Ypresian

{{short description|First age of the Eocene Epoch}}
{{Infobox geologic timespan
| name                         = Ypresian
| color                        = Ypresian
| top_bar                      =
| time_start                   = 56.0
| time_end                     = 47.8
| image_map                    = Ypresian Earth 50 mya.jpg
| caption_map                  = Earth ~50 mya
| image_outcrop                = Klondike Mountain Formation outcrop - Site A0307.JPG
| caption_outcrop              = [[Klondike Mountain Formation]], Republic, Washington
| image_art                    =
| caption_art                  =
<!--Chronology-->  
| timeline                     = Paleogene
| formerly_part_of             = [[Tertiary period|Tertiary]] [[Geological period|Period]]/[[System (stratigraphy)|System]]
<!--Etymology-->
| name_formality               = Formal
| name_accept_date             = 
| alternate_spellings          = 
| synonym1                     =
| synonym1_coined              =
| synonym2                     =
| synonym2_coined              =
| synonym3                     =
| synonym3_coined              =
| nicknames                    =
| former_names                 =
| proposed_names               =
<!--Usage Information--> 
| celestial_body               = earth
| usage                        = Global ([[International Commission on Stratigraphy|ICS]])
| timescales_used              = ICS Time Scale
| formerly_used_by             =
| not_used_by                  =
<!--Definition-->
| chrono_unit                  = Age
| strat_unit                   = stage
| proposed_by                  = [[André Hubert Dumont|Dumont]]
| type_section                 =
| timespan_formality           = Formal
| lower_boundary_def           = Strong negative anomaly in [[Delta 13C|δ<sup>13</sup>C]] values at the [[Paleocene–Eocene Thermal Maximum|PETM]]<ref name="Aubry 2007">{{cite journal|last1=Aubry|first1=Marie-Pierre |last2=Ouda |first2=Khaled |last3=Dupuis |first3=Christian |author4=William A. Berggren |author5=John A. Van Couvering  |author6=Working Group on the Paleocene/Eocene Boundary |title=The Global Standard Stratotype-section and Point (GSSP) for the base of the Eocene Series in the Dababiya section (Egypt)|journal=Episodes|year=2007|volume=30|issue=4|pages=271–286|url=http://www.stratigraphy.org/GSSP/file11.pdf|doi=10.18814/epiiugs/2007/v30i4/003 |doi-access=free}}</ref>
| lower_gssp_location          = Dababiya section, [[Luxor]], Egypt<ref name="Aubry 2007"/>
| lower_gssp_coords            = {{Coord|25.5000|N|32.5311|E|display=inline}}
| lower_gssp_accept_date       = 2003<ref name="Aubry 2007"/>
| upper_boundary_def           = [[First appearance datum|FAD]] of the calcareous nannofossil ''[[Blackites inflatus]]''
| upper_gssp_location          = Gorrondatxe section, [[Pyrenees|Western Pyrenees]], [[Basque Country (greater region)|Basque Country]], Spain
| upper_gssp_coords            = {{Coord|43.3796|N|3.0143|W|display=inline}}
| upper_gssp_accept_date       = April 2011<ref>{{cite journal|last1=Molina|first1=Eustoquio |last2=Alegret |first2=Laia |last3=Apellaniz |first3=Estibaliz |last4=Bernaola |first4=Gilen |last5=Caballero |first5=Fernando |author6=Jaume Dinarès-Turell |last7=Hardenbol |first7=Jan |author8=Claus Heilmann-Clausen |author9=Juan C. Larrasoana |author10=Hanspeter Luterbacher |author11=Simonetta Monechi |author12=Silvia Ortiz |author13=Xabier Orue-Etxebarria |author14=Aitor Payros |author15=Victoriano Pujalte |author16=Francisco J. Rodríguez-Tobar |author17=Flavia Tori |author18=Josep Tosquella |author19=Alfred Uchman |title=The Global Stratotype Section and Point (GSSP) for the base of the Lutetian Stage at the Gorrondatxe section, Spain|journal=Episodes|year=2011|volume=34|issue=2|pages=86–108|url=http://wzar.unizar.es/perso/emolina/pdf/Molina2011Episodes.pdf|doi=10.18814/epiiugs/2011/v34i2/006 |doi-access=free }}</ref>
<!--Atmospheric and Climatic Data-->
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}}

In the [[geologic timescale]] the '''Ypresian''' is the oldest [[age (geology)|age]] or lowest [[stage (stratigraphy)|stratigraphic stage]] of the [[Eocene]]. It spans the time between {{ma|Ypresian|and}} {{Ma|Lutetian|Ma}}, is preceded by the [[Thanetian]] Age (part of the [[Paleocene]]) and is followed by the Eocene [[Lutetian]] Age. The Ypresian is consistent with the Lower Eocene (Early Eocene).

==Events==
{{See also|Cambay Shale Formation|pCO2|l2=p{{chem2|CO2}}|δ18O|l3={{delta|18|O}}}}
The Ypresian Age begins during the throes of the [[Paleocene–Eocene Thermal Maximum]] (PETM). The [[Fur Formation]] in [[Denmark]], the [[Messel shales]] in [[Germany]], the [[Oise amber]] of France and [[Cambay amber]] of India are of this age.  The [[Eocene Okanagan Highlands]] are an uplands subtropical to temperate series of lakes from the Ypresian.<ref name="Greenwood2005">{{cite journal |last1=Greenwood |first1=D.R. |last2=Archibald |first2=S.B. |last3=Mathewes |first3=R.W |last4=Moss |first4=P.T. |year=2005 |title=Fossil biotas from the Okanagan Highlands, southern British Columbia and northeastern Washington State: climates and ecosystems across an Eocene landscape |journal=Canadian Journal of Earth Sciences |volume=42 |issue=2 |pages=167–185|bibcode=2005CaJES..42..167G |doi=10.1139/e04-100}}</ref><ref name="GCL2011">{{cite journal |last1=Archibald |first1=S. |last2=Greenwood |first2=D. |last3=Smith |first3=R. |last4=Mathewes |first4=R. |last5=Basinger |first5=J. |year=2011 |title=Great Canadian ''Lagerstätten'' 1. Early Eocene Lagerstätten of the Okanagan Highlands (British Columbia and Washington State) |journal=Geoscience Canada |volume=38 |issue=4 |pages=155–164}}</ref><ref name="Lowe2018">{{cite journal |last1=Lowe |first1=A. J. |last2=Greenwood |first2=D. R. |last3=West |first3=C. K. |last4=Galloway |first4=J. M. |last5=Sudermann |first5=M. |last6=Reichgelt |first6=T. |year=2018 |title=Plant community ecology and climate on an upland volcanic landscape during the Early Eocene Climatic Optimum: McAbee Fossil Beds, British Columbia, Canada |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=511 |pages=433–448|doi=10.1016/j.palaeo.2018.09.010 |bibcode=2018PPP...511..433L |s2cid=134962126 }}</ref>

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 low [[oxygen-18]] isotopes,<ref>{{Cite journal |last1=Bijl |first1=Peter K. |last2=Schouten |first2=Stefan |last3=Sluijs |first3=Appy |last4=Reichart |first4=Gert-Jan |last5=Zachos |first5=James C. |last6=Brinkhuis |first6=Henk |date=October 2009 |title=Early Palaeogene temperature evolution of the southwest Pacific Ocean |url=https://www.nature.com/articles/nature08399 |journal=Nature |language=en |volume=461 |issue=7265 |pages=776–779 |doi=10.1038/nature08399 |pmid=19812670 |bibcode=2009Natur.461..776B |hdl=1874/385779 |s2cid=4358350 |issn=1476-4687|hdl-access=free }}</ref><ref>{{Cite journal |last1=Hollis |first1=Christopher J. |last2=Handley |first2=Luke |last3=Crouch |first3=Erica M. |last4=Morgans |first4=Hugh E.G. |last5=Baker |first5=Joel A. |last6=Creech |first6=John |last7=Collins |first7=Katie S. |last8=Gibbs |first8=Samantha J. |last9=Huber |first9=Matthew |last10=Schouten |first10=Stefan |last11=Zachos |first11=James C. |last12=Pancost |first12=Richard D. |date=2009-02-01 |title=Tropical sea temperatures in the high-latitude South Pacific during the Eocene |url=https://doi.org/10.1130/G25200A.1 |journal=Geology |volume=37 |issue=2 |pages=99–102 |doi=10.1130/g25200a.1 |bibcode=2009Geo....37...99H |issn=1943-2682|url-access=subscription }}</ref><ref>{{Cite journal |last1=Zachos |first1=James |last2=Pagani |first2=Mark |last3=Sloan |first3=Lisa |last4=Thomas |first4=Ellen |last5=Billups |first5=Katharina |date=2001-04-27 |title=Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present |url=https://www.science.org/doi/10.1126/science.1059412 |journal=Science |language=en |volume=292 |issue=5517 |pages=686–693 |doi=10.1126/science.1059412 |pmid=11326091 |bibcode=2001Sci...292..686Z |issn=0036-8075|url-access=subscription }}</ref> high levels of [[atmospheric pCO2|atmospheric p{{chem2|CO2}}]],<ref>{{Cite journal |last1=Beerling |first1=David J. |last2=Royer |first2=Dana L. |date=July 2011 |title=Convergent Cenozoic CO2 history |url=https://www.nature.com/articles/ngeo1186 |journal=Nature Geoscience |language=en |volume=4 |issue=7 |pages=418–420 |doi=10.1038/ngeo1186 |bibcode=2011NatGe...4..418B |issn=1752-0908|url-access=subscription }}</ref><ref>{{Cite journal |last1=Zachos |first1=James C. |last2=Dickens |first2=Gerald R. |last3=Zeebe |first3=Richard E. |date=January 2008 |title=An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics |journal=Nature |language=en |volume=451 |issue=7176 |pages=279–283 |doi=10.1038/nature06588 |pmid=18202643 |bibcode=2008Natur.451..279Z |s2cid=4360841 |issn=1476-4687|doi-access=free }}</ref> and low meridional thermal gradients.<ref>{{Cite journal |last1=Cramwinckel |first1=Margot J. |last2=Huber |first2=Matthew |last3=Kocken |first3=Ilja J. |last4=Agnini |first4=Claudia |last5=Bijl |first5=Peter K. |last6=Bohaty |first6=Steven M. |last7=Frieling |first7=Joost |last8=Goldner |first8=Aaron |last9=Hilgen |first9=Frederik J. |last10=Kip |first10=Elizabeth L. |last11=Peterse |first11=Francien |last12=van der Ploeg |first12=Robin |last13=Röhl |first13=Ursula |last14=Schouten |first14=Stefan |last15=Sluijs |first15=Appy |date=July 2018 |title=Synchronous tropical and polar temperature evolution in the Eocene |url=https://www.nature.com/articles/s41586-018-0272-2 |journal=Nature |language=en |volume=559 |issue=7714 |pages=382–386 |doi=10.1038/s41586-018-0272-2 |pmid=29967546 |bibcode=2018Natur.559..382C |hdl=1874/366626 |s2cid=256767465 |issn=1476-4687|hdl-access=free }}</ref> [[Biodiversity]] has been reported to have been significantly impacted by the conditions prevalent during the EECO. For instance, there were biotic turnovers among [[marine producer]]s such as [[calcareous nannofossils]] among others etc.<ref>{{Cite journal |last1=Cappelli |first1=C. |last2=Bown |first2=P. R. |last3=Westerhold |first3=T. |last4=Bohaty |first4=S. M. |last5=Riu |first5=M. |last6=Lobba |first6=V. |last7=Yamamoto |first7=Y. |last8=Agnini |first8=C. |date=December 2019 |title=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) |journal=Paleoceanography and Paleoclimatology |language=en |volume=34 |issue=12 |pages=1913–1930 |doi=10.1029/2019PA003686 |bibcode=2019PaPa...34.1913C |s2cid=210245165 |issn=2572-4517|doi-access=free |hdl=11577/3322441 |hdl-access=free }}</ref><ref>{{Cite journal |last1=Schneider |first1=Leah J. |last2=Bralower |first2=Timothy J. |last3=Kump |first3=Lee R. |date=October 2011 |title=Response of nannoplankton to early Eocene ocean destratification |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018211003373 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=310 |issue=3–4 |pages=152–162 |doi=10.1016/j.palaeo.2011.06.018|bibcode=2011PPP...310..152S |url-access=subscription }}</ref>

==Stratigraphic definition==
{{See also|List of geochronologic names}}
The Ypresian Stage was introduced in scientific literature by [[Belgium|Belgian]] geologist [[André Hubert Dumont]] in 1850. The Ypresian is named after the [[Flanders|Flemish]] city of [[Ypres]] in Belgium (spelled ''Ieper'' in Dutch). The definitions of the original stage were totally different from the modern ones.<ref>Steurbaut (2006)</ref> The Ypresian shares its name with the Belgian [[Ieper Group]] (French: ''Groupe d'Ypres''), which has an Ypresian age.

The base of the Ypresian Stage is defined at a strong negative anomaly in [[Delta 13C|δ<sup>13</sup>C]] values at the [[PETM]]. The official reference profile ([[GSSP]]) for the base of the Ypresian is the Dababiya profile near the [[Egypt]]ian city of [[Luxor]].<ref>The GSSP was established by Dupuis ''et al.'' (2003)</ref> Its original [[type section]] was located in the vicinity of Ieper.

The top of the Ypresian (the base of the Lutetian) is identified by the first appearance of the [[foraminifera]] [[genus]] ''[[Hantkenina]]'' in the fossil record.

The Ypresian Stage overlaps the upper Neustrian and most of the Grauvian [[European Land Mammal Mega Zone]]s (it spans the [[Mammal Paleogene zones]] 7 through 10.<ref name="MP">{{cite web |last = Alroy |first = John | page = The Paleobiology Database | title = Mammal Paleogene zones |url = https://paleodb.org/cgi-bin/bridge.pl?action=processViewScale&scale_no=125 | access-date = 15 July 2009}}</ref>), the [[Wasatchian]] and lower and middle [[Bridgerian]] [[North American Land Mammal Ages]], the [[Casamayoran]] [[South American Land Mammal Age]] and the [[Bumbanian]] and most of the [[Arshantan]] [[Asian Land Mammal Ages]]. It is also coeval with the upper Wangerripian and lowest Johannian regional stages of [[Australia]] and the Bulitian, Penutian, and Ulatisian regional stages of [[California]].

==References==
{{Reflist}}

===Literature===
{{Wikisource portal|Cenozoic#Paleogene}}
*[[André Hubert Dumont|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 Belgique '''16''' (2), pp.&nbsp;351–373. {{in lang|fr}}
*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'', Micropaleontology '''49''' (1), pp.&nbsp;41–59, {{ISSN|0026-2803}}.
*Gradstein, F. M.; Ogg, J. G. & Smith, A. G.; 2004: ''A Geologic Time Scale 2004'', [[Cambridge University Press]].
*Steurbaut, É.; 2006: [http://popups.ulg.ac.be/Geol/docannexe.php?id=1107 ''Ypresian''] {{Webarchive|url=https://web.archive.org/web/20120218045549/http://popups.ulg.ac.be/Geol/docannexe.php?id=1107 |date=2012-02-18 }}, Geologica Belgica '''9''' (1–2), pp.&nbsp;73–93.

==External links==
*[https://web.archive.org/web/20100822030507/http://www.stratigraphy.org/bak/geowhen/stages/Ypresian.html GeoWhen Database – Ypresian]
*[http://stratigraphy.science.purdue.edu/charts/Timeslices/2_Paleogene.pdf Paleogene timescale], at the website of the subcommission for stratigraphic information of the ICS
*[https://web.archive.org/web/20060518101848/http://norges.uio.no/timescale/Fig19.1_Pal_bio_colB.pdf Stratigraphic chart of the Paleogene], at the website of Norges Network of offshore records of geology and stratigraphy

{{Paleogene Footer}}
{{Geological history|p|c}}

[[Category:Ypresian| ]]
[[Category:Eocene geochronology]]
[[Category:Ypresian first appearances| ]]
[[Category:Geological ages]]