Thanetian

System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Neogene Miocene Aquitanian younger
Paleogene Oligocene Chattian 23.03–28.1
Rupelian 28.1–33.9
Eocene Priabonian 33.9–38.0
Bartonian 38.0–41.3
Lutetian 41.3–47.8
Ypresian 47.8–56.0
Paleocene Thanetian 56.0–59.2
Selandian 59.2–61.6
Danian 61.6–66.0
Cretaceous Upper/
Late
Maastrichtian older
Subdivision of the Paleogene Period
according to the ICS, as of January 2013.[1]

The Thanetian is, in the ICS Geologic timescale, the latest age or uppermost stratigraphic stage of the Paleocene Epoch or series. It spans the time between 59.2 and 56 Ma. The Thanetian is preceded by the Selandian age and followed by the Ypresian age (part of the Eocene).[1] The Thanetian is sometimes referred to as the Late Paleocene sub-epoch.

Stratigraphic definition

The Thanetian was established by Swiss geologist Eugène Renevier in 1873. The Thanetian is named after the Thanet Sand Formation, the oldest Cenozoic deposit of the London Basin, which was first identified in the area of Kent (southern England) known as the Isle of Thanet.

The base of the Thanetian stage is laid at the base of magnetic chronozone C26n. The references profile (Global Boundary Stratotype Section and Point) is in the Zumaia section (43° 18'N, 2° 16'W) at the beach of Itzurun, Pais Vasco, northern Spain.[2] Fossils of the unicellular planktonic marine coccolithophore Areoligeria 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 the global thermal maximum at the Paleocene-Eocene boundary.

The Thanetian stage is coeval the lower Neustrian European land mammal age (it spans the Mammal Paleogene zone 6 and part of zones 1 through 5.[3]), the upper Tiffanian and Clarkforkian North American land mammal ages, the Riochican and part of the Itaboraian South American land mammal ages and the upper Nongshanian and Gashatan Asian land mammal ages. The Thanetian is contemporary with the middle Wangerripian regional stage of Australia and the upper Ynezian regional stage of California. It overlaps the obsolete regional stages Landenian and Heersian of Belgium.

Palaeontology

The Sézanne flora is a fossil assemblage preserved in freshwater limestone deposits at Sézanne, laid down during the Thanetian age, when Europe enjoyed a tropical climate. In the lagerstätte, leaves, entire flowers and seeds are minutely preserved. Also, the first representatives of Proboscidea appeared, Eritherium.[4]

See also

Notes

  1. 1 2 Cohen, K.M.; Finney, S.; Gibbard, P.L. (2013), International Chronostratigraphic Chart (PDF), International Commission on Stratigraphy.
  2. Proposed by Dinarès-Turell et al. (2007), ratified by the IUGS in 2008
  3. Alroy, John. "Mammal Paleogene zones". p. The Paleobiology Database. Retrieved 15 July 2009.
  4. 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. doi:10.1073/pnas.0900251106. PMC 2705600. PMID 19549873.

Literature

Wikisource has original works on the topic: Cenozoic#Paleogene

External links

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