Cretaceous–Paleogene extinction event

An airtist's renderin o an asteroid a few kilometers athort collidin wi the Yird. Sic an impact can release the equivalent energy o several million nuclear wappens detonatin simultaneously.

The Cretaceous–Paleogene (K–Pg) extinction event,[lower-alpha 1] an aw kent as the Cretaceous–Tertiary (K–T) extinction,[lower-alpha 2] wis a sudden mass extinction o some three-quarters o the plant an ainimal speshies on Yird,[2][3][4] approximately 66 million years aby.[3]


  1. The abbreviation is derived frae the juxtaposition o K, the common abbreviation for the Cretaceous, that in turn oreeginates frae the correspondent German term Kreide, an Pg, that is the abbreviation for the Paleogene.
  2. The umwhile designation includes the term 'Tertiary' (abbreviatit as T), that is nou discouraged as a formal geochronological unit bi the Internaitional Commission on Stratigraphy.[1]


  1. Ogg, James G.; Gradstein, F. M; Gradstein, Felix M. (2004). A geologic time scale 2004. Cambridge, UK: Cambridge University Press. ISBN 978-0-521-78142-8.
  2. "International Chronostratigraphic Chart". International Commission on Stratigraphy. 2015. Archived frae the oreeginal on May 30, 2014. Retrieved 29 April 2015. Unknown parameter |deadurl= ignored (help)
  3. 3.0 3.1 Renne, Paul R.; Deino, Alan L.; Hilgen, Frederik J.; Kuiper, Klaudia F.; Mark, Darren F.; Mitchell, William S.; Morgan, Leah E.; Mundil, Roland; Smit, Jan (7 February 2013). "Time Scales of Critical Events Around the Cretaceous-Paleogene Boundary" (PDF). Science. 339 (6120): 684–687. Bibcode:2013Sci...339..684R. doi:10.1126/science.1230492. PMID 23393261.
  4. Fortey, Richard (1999). Life: A Natural History of the First Four Billion Years of Life on Earth. Vintage. pp. 238–260. ISBN 978-0-375-70261-7.