Pliocene

Pliocene
5.333 ± 0.08 – 2.58 ± 0.04 Ma
↓
A map of Earth as it appeared 5 million years ago during the Pliocene Epoch, Zanclean Age
Chronology
Etymology
Name formalityFormal
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitEpoch
Stratigraphic unitSeries
Time span formalityFormal
Lower boundary definitionBase of the Thvera magnetic event (C3n.4n), which is only 96 ka (5 precession cycles) younger than the GSSP
Lower boundary GSSPHeraclea Minoa section, Heraclea Minoa, Cattolica Eraclea, Sicily, Italy
37°23′30″N 13°16′50″E / 37.3917°N 13.2806°E / 37.3917; 13.2806
Lower GSSP ratified2000[4]
Upper boundary definition
Upper boundary GSSPMonte San Nicola Section, Gela, Sicily, Italy
37°08′49″N 14°12′13″E / 37.1469°N 14.2035°E / 37.1469; 14.2035
Upper GSSP ratified2009 (as base of Quaternary and Pleistocene)[5]
Part of a series on
Human history
and prehistory
↑ before Homo   (Pliocene epoch)
Prehistory
Stone Age
Lower Paleolithic
Middle Paleolithic
Early Homo sapiens
Upper Paleolithic
Behavioral modernity
Neolithic
Cradle of civilization
Protohistory
Copper Age
Bronze Age
Bronze Age collapse
Iron Age
Recorded history
Ancient history
Post-classical history
Modern history
↓ Future   (Holocene epoch)

The Pliocene ( /ˈplaɪ.əsiːn, ˈplaɪ.oʊ-/ PLY-ə-seen, PLY-oh-;[6][7] also Pleiocene)[8] is the epoch in the geologic time scale that extends from 5.33 to 2.58[9] million years ago (Ma). It is the second and most recent epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch. Prior to the 2009 revision of the geologic time scale, which placed the four most recent major glaciations entirely within the Pleistocene, the Pliocene also included the Gelasian Stage, which lasted from 2.59 to 1.81 Ma, and is now included in the Pleistocene.[10]

As with other older geologic periods, the geological strata that define the start and end are well-identified but the exact dates of the start and end of the epoch are slightly uncertain. The boundaries defining the Pliocene are not set at an easily identified worldwide event but rather at regional boundaries between the warmer Miocene and the relatively cooler Pleistocene. The upper boundary was set at the start of the Pleistocene glaciations.

  1. ^ Krijgsman, W.; Garcés, M.; Langereis, C. G.; Daams, R.; Van Dam, J.; Van Der Meulen, A. J.; Agustí, J.; Cabrera, L. (1996). "A new chronology for the middle to late Miocene continental record in Spain". Earth and Planetary Science Letters. 142 (3–4): 367–380. Bibcode:1996E&PSL.142..367K. doi:10.1016/0012-821X(96)00109-4.
  2. ^ Retallack, G. J. (1997). "Neogene Expansion of the North American Prairie". PALAIOS. 12 (4): 380–390. doi:10.2307/3515337. JSTOR 3515337. Retrieved 11 February 2008.
  3. ^ "ICS Timescale Chart" (PDF). www.stratigraphy.org.
  4. ^ Van Couvering, John; Castradori, Davide; Cita, Maria; Hilgen, Frederik; Rio, Domenico (September 2000). "The base of the Zanclean Stage and of the Pliocene Series" (PDF). Episodes. 23 (3): 179–187. doi:10.18814/epiiugs/2000/v23i3/005.
  5. ^ Gibbard, Philip; Head, Martin (September 2010). "The newly-ratified definition of the Quaternary System/Period and redefinition of the Pleistocene Series/Epoch, and comparison of proposals advanced prior to formal ratification" (PDF). Episodes. 33 (3): 152–158. doi:10.18814/epiiugs/2010/v33i3/002. Retrieved 8 December 2020.
  6. ^ "Pliocene". Merriam-Webster.com Dictionary. Merriam-Webster.
  7. ^ "Pliocene". Dictionary.com Unabridged (Online). n.d.
  8. ^ "Pleiocene". Dictionary.com Unabridged (Online). n.d.
  9. ^ See the 2014 version of the ICS geologic time scale Archived 2014-05-30 at the Wayback Machine
  10. ^ Ogg, James George; Ogg, Gabi; Gradstein F. M. (2008). The Concise Geologic Time Scale. Cambridge University Press. pp. 150–1. ISBN 9780521898492.