Selandian

The Selandian is a stage in the Paleocene. It spans the time between 61.6 and 59.2 Ma. It is preceded by the Danian and followed by the Thanetian.^[4] Sometimes^[when?] the Paleocene is subdivided^{[by whom?]} in subepochs, in which the Selandian forms the "middle Paleocene".

Stratigraphic definition

The Selandian was introduced in scientific literature by Danish geologist Alfred Rosenkrantz in 1924. It is named after the

The top of the Selandian (the base of the Thanetian) is laid at the base of magnetic chronozone C26n.

The Selandian Stage overlaps with the lower part of the

The start of the Selandian represents a sharp depositional change in the North Sea Basin, where there is a shift to siliciclastic deposition due to the uplift and erosion of the Scotland-Shetland area after nearly 40 million years of calcium carbonate deposition.^[7] This change occurs at the same time as the onset of a foreland basin formation in Spitsbergen due to compression between Greenland and Svalbard,^[8] suggesting a common tectonic cause that altered the relative motions of the Greenland Plate and the Eurasian Plate. This plate reorganisation event is also manifest as a change in seafloor spreading direction in the Labrador Sea around this time.^[9]

Fauna and Flora

The fauna of the Selandian consisted of giant snakes (

.

The flora was composed of

palm trees

.

References

1. doi:10.1016/j.gloplacha.2005.01.001
   .
2. ^ "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy.
3. ^
   doi:10.18814/epiiugs/2011/v34i4/002
   .
4. ^ International Commission on Stratigraphy 2017
5. ^ Selandien, Den Store Danske Encyklopædi
6. ^ See for example Arenillas et al. (2008) or Bernaola et al. (2009) for a description of the Danian-Selandidan boundary
7. doi:10.1016/j.palaeo.2005.01.005
   .
8. PMID 28754976
   .
9. doi:10.1029/2011jb008942
   .
10. ^ Kwok R (4 February 2009). "Scientists find world's biggest snake".
    doi:10.1038/news.2009.80
    .
11. ^ Koeberl C, MacLeod KG, eds. (2002). Catastrophic events and mass extinctions: Impacts and beyond. Geological Society of America. pp. 303–4.

Further reading

Wikisource has original works on the topic: Cenozoic#Paleogene

• Arenillas I, Molina E, Ortiz S, Schmitz B (2008). "Foraminiferal and δ¹³C isotopic event-stratigraphy across the Danian-Selandian transition at Zumaya (northern Spain): chronostratigraphic implications". Terra Nova. 20 (1): 38–44.
  S2CID 129044742
  .
• Bernaola G, Martín-Rubio M, Baceta JI (2009). "New high resolution calcareous nannofossil analysis across the Danian-Selandian transition at the Zumaia section: comparisons with South Tethys and Danish sections". Geologica Acta. 7 (1–2): 79–92.
• Gradstein FM, Ogg JG, Smith AG (2004). A Geologic Time Scale. Cambridge University Press.
• Rosenkrantz A (March 1921). "En ny københavnsk Lokalitet for forsteningsførende Paleocæn". Meddelelser Fra Dansk Geologisk Forening (in Danish). 5: 1–10.
• Rosenkrantz A (1924). "De københavnske Grønsandslag og deres Placering i den danske Lagrække". Meddelelser Fra Dansk Geologisk Forening (in Danish). 6: 1–39.

External links

• GeoWhen Database - Selandian
• 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

43°18′02″N 2°15′34″W / 43.30056°N 2.25944°W / 43.30056; -2.25944