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TheThanetian is, in theICS Geologic timescale, the latestage or uppermoststratigraphic stage of thePaleocene Epoch orSeries. It spans the time between59.24 and56 Ma. The Thanetian is preceded by theSelandian Age and followed by theYpresian Age (part of theEocene).^[5] The Thanetian is sometimes referred to as the LatePaleocene.

Stratigraphic definition

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The Thanetian was established bySwiss geologistEugène Renevier in 1873. The Thanetian is named after theThanet Formation, the oldestCenozoic deposit of theLondon Basin, which was first identified in the area ofKent (southernEngland) known as theIsle of Thanet.

The base of the Thanetian Stage is laid at the base of magneticchronozone C26n. The references profile (Global Boundary Stratotype Section and Point) is in theZumaia section (43° 18'N, 2° 16'W) at the beach of Itzurun,Pais Vasco, northernSpain.^[6] Fossils of the unicellular planktonic marinecoccolithophoreAreoligeria gippingensis make their first appearance at the base of the Thanetian, and help define its lowest stratigraphic boundary.

The top of the Thanetian Stage (the base of the Ypresian) is defined at a strong negative anomaly in δ¹³C values at theglobal thermal maximum at the Paleocene-Eocene boundary.

The Thanetian Stage is coeval the lower NeustrianEuropean land mammal age (it spans theMammal Paleogene zone 6 and part of zones 1 through 5.^[7]), the upperTiffanian andClarkforkian North American land mammal ages, theRiochican and part of theItaboraian South American land mammal ages and the upper Nongshanian andGashatan Asian land mammal ages. The Thanetian is contemporary with the middle Wangerripian regional stage ofAustralia and the upper Ynezian regional stage ofCalifornia. It overlaps the obsolete regional stagesLandenian and Heersian ofBelgium.

Palaeontology

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The Sézanne flora is a fossil assemblage preserved in freshwater limestone deposits atSézanne, laid down during the Thanetian Age, when Europe enjoyed a tropical climate. In thelagerstätte, leaves, entire flowers and seeds are minutely preserved. Also, the first representatives ofProboscidea appeared,Eritherium.^[8]

Climate

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This period was characterized by temperatures warmer than those of today.^[9]

References

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^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.
^"International Chronostratigraphic Chart"(PDF).International Commission on Stratigraphy. September 2023. RetrievedDecember 16, 2024.
^Schmitz, B.; Pujalte, V.; Molina, E.; Monechi, S.; Orue-Etxebarria, X.; Speijer, R. P.; Alegret, L.; Apellaniz, E.; Arenillas, I.; Aubry, M.-P.; Baceta, J.-I.; Berggren, W. A.; Bernaola, G.; Caballero, F.; Clemmensen, A.; Dinarès-Turell, J.; Dupuis, C.; Heilmann-Clausen, C.; Orús, A. H.; Knox, R.; Martín-Rubio, M.; Ortiz, S.; Payros, A.; Petrizzo, M. R.; von Salis, K.; Sprong, J.; Steurbaut, E.; Thomsen, E. (2011)."The global Stratotype Sections and Points for the bases of the Selandian (Middle Paleocene) and Thanetian (Upper Paleocene Paleocene) stages at Zumaia, Spain".Episodes.34 (4):220–243.doi:10.18814/epiiugs/2011/v34i4/002.
^^a ^b ^cAubry, 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.
^International Commission on Stratigraphy 2017
^Proposed by Dinarès-Turellet al. (2007), ratified by theIUGS in 2008
^Alroy, John."Mammal Paleogene zones". p. The Paleobiology Database.Archived from the original on 12 October 2012. Retrieved15 July 2009.
^Emmanuel Gheerbrant (2009)."Paleocene emergence of elephant relatives and the rapid radiation of African ungulates".Proceedings of the National Academy of Sciences of the United States of America.106 (26):10717–10721.Bibcode:2009PNAS..10610717G.doi:10.1073/pnas.0900251106.PMC 2705600.PMID 19549873.
^"AR6 Climate Change 2021: The Physical Science Basis — IPCC". Retrieved24 August 2021.

Literature

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Wikisource has original works on the topic:Cenozoic#Paleogene

Dinarès-Turell, J.; Baceta, J. I.; Bernaola, G.; Orue-Etxebarria, X. & Pujalte, V.;2007:Closing the Mid-Palaeocene gap: Toward a complete astronomically tuned Palaeocene Epoch and Selandian and Thanetian GSSPs at Zumaia (Basque Basin, W. Pyrenees), Earth and Planetary Science Letters262: pp 450–467.
Gradstein, F.M.; Ogg, J.G. & Smith, A.G.;2004:A Geologic Time Scale 2004,Cambridge University Press.
Renevier, E.;1873:Tableau des terrains sédimentaires formés pendant les époques de la phase organique du globe terrestre, Bulletin de la Société Vaudoise des Sciences Naturelles (Lausanne)12: pp 218–252.

External links

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GeoWhen Database - Thanetian
Paleogene timescale, at the website of the subcommission for stratigraphic information of the ICS
Stratigraphic chart of the Paleogene, at the website of Norges Network of offshore records of geology and stratigraphy

Geological history of Earth

Cenozoic Era
(present–66.0 Ma)

Quaternary(present–2.58 Ma)	Holocene (present–11.7 ka) Pleistocene (11.7 ka–2.58 Ma)
Neogene(2.58–23.0 Ma)	Pliocene (2.59–5.33 Ma) Miocene (5.33–23.0 Ma)
Paleogene(23.0–66.0 Ma)	Oligocene (23.0–33.9 Ma) Eocene (33.9–56.0 Ma) Paleocene (56.0–66.0 Ma)

Mesozoic Era
(66.0–252 Ma)

Cretaceous(66.0–145 Ma)	Late (66.0–100 Ma) Early (100–145 Ma)
Jurassic(145–201 Ma)	Late (145–164 Ma) Middle (164–174 Ma) Early (174–201 Ma)
Triassic(201–252 Ma)	Late (201–237 Ma) Middle (237–247 Ma) Early (247–252 Ma)

Paleozoic Era
(252–539 Ma)

Permian(252–299 Ma)	Lopingian (252–260 Ma) Guadalupian (260–272 Ma) Cisuralian (272–299 Ma)
Carboniferous(299–359 Ma)	Pennsylvanian (299–323 Ma) Mississippian (323–359 Ma)
Devonian(359–419 Ma)	Late (359–383 Ma) Middle (383–393 Ma) Early (393–419 Ma)
Silurian(419–444 Ma)	Pridoli (419–423 Ma) Ludlow (423–427 Ma) Wenlock (427–433 Ma) Llandovery (433–444 Ma)
Ordovician(444–485 Ma)	Late (444–458 Ma) Middle (458–470 Ma) Early (470–485 Ma)
Cambrian(485–539 Ma)	Furongian (485–497 Ma) Miaolingian (497–509 Ma) Series 2 (509–521 Ma) Terreneuvian (521–539 Ma)

Proterozoic Eon
(539 Ma–2.5 Ga)

Neoproterozoic(539 Ma–1 Ga)	Ediacaran (539–635 Ma) Cryogenian (635–720 Ma) Tonian (720 Ma–1 Ga)
Mesoproterozoic(1–1.6 Ga)	Stenian (1–1.2 Ga) Ectasian (1.2–1.4 Ga) Calymmian (1.4–1.6 Ga)
Paleoproterozoic(1.6–2.5 Ga)	Statherian (1.6–1.8 Ga) Orosirian (1.8–2.05 Ga) Rhyacian (2.05–2.3 Ga) Siderian (2.3–2.5 Ga)