Editing Paleogene (section)

==== Paleocene ====
The Paleocene is the first series/epoch of the Paleogene and lasted from 66.0 Ma to 56.0 Ma. It is divided into three stages: the [[Danian]] 66.0 - 61.6 Ma; [[Selandian]] 61.6 - 59.2 Ma; and, [[Thanetian]] 59.2 - 56.0 Ma.<ref name=":0">{{Citation |last1=Vandenberghe |first1=N. |title=Chapter 28 - The Paleogene Period |date=2012-01-01 |work=The Geologic Time Scale |pages=855–921 |editor-last=Gradstein |editor-first=Felix M. |url=https://www.sciencedirect.com/science/article/pii/B9780444594259000287 |access-date=2024-07-15 |place=Boston |publisher=Elsevier |isbn=978-0-444-59425-9 |last2=Hilgen |first2=F. J. |last3=Speijer |first3=R. P. |last4=Ogg |first4=J. G. |last5=Gradstein |first5=F. M. |last6=Hammer |first6=O. |last7=Hollis |first7=C. J. |last8=Hooker |first8=J. J. |editor2-last=Ogg |editor2-first=James G. |editor3-last=Schmitz |editor3-first=Mark D. |editor4-last=Ogg |editor4-first=Gabi M. |archive-date=2015-09-24 |archive-url=https://web.archive.org/web/20150924145807/http://www.sciencedirect.com/science/article/pii/B9780444594259000287 |url-status=live }}</ref> The GSSP for the base of the Cenozoic, Paleogene and Paleocene is at Oued Djerfane, west of [[El Kef]], [[Tunisia]]. It is marked by an [[iridium anomaly]] produced by an [[asteroid]] impact, and is associated with the Cretaceous–Paleogene extinction event. The boundary is defined as the rusty colored base of a 50 cm thick [[clay]], which would have been deposited over only a few days. Similar layers are seen in marine and continental deposits worldwide. These layers include the iridium anomaly, [[Tektite|microtektites]], [[nickel]]-rich [[spinel]] crystals and [[shocked quartz]], all indicators of a major extraterrestrial impact. The remains of the crater are found at [[Chicxulub crater|Chicxulub]] on the [[Yucatan Peninsula]] in [[Mexico]]. The extinction of the [[Dinosaur|non-avian dinosaurs]], [[Ammonoidea|ammonites]] and dramatic changes in [[Plankton|marine plankton]] and many other groups of organisms, are also used for correlation purposes.<ref name=":0" />