|Subdivisions of the Quaternary System|
|Subdivision of the Quaternary period according to the ICS, as of 2018.
For the Holocene, dates are relative to the year 2000 (e.g. Greenlandian began 11,700 years before 2000). For the begin of the Northgrippian a date of 8,236 years before 2000 has been set . The Meghalayan has been set to begin 4,250 years before 2000, apparently from a calibrated radio-carbon date of 4,200 years BP i.e. before 1950.[clarification needed]
'Chibanian' and 'Tarantian' are informal, unofficial names proposed to replace the also informal, unofficial 'Middle Pleistocene' and 'Upper Pleistocene' subseries/subepochs respectively.
In Europe and North America, the Holocene is subdivided into Preboreal, Boreal, Atlantic, Subboreal, and Subatlantic stages of the Blytt–Sernander time scale. There are many regional subdivisions for the Upper or Late Pleistocene; usually these represent locally recognized cold (glacial) and warm (interglacial) periods. The last glacial period ends with the cold Younger Dryas substage.
In the geologic time scale, the Northgrippian is the middle of the three ages of the Holocene epoch which lies in the Quaternary period. It was officially ratified by the International Commission on Stratigraphy in July 2018 along with the Greenlandian and the Meghalayan.
- Cohen, K.M.; Finney, S.C.; Gibbard, P.L.; Fan, J.-X. "International Chronostratigraphic Chart". International Commission on Stratigraphy. Retrieved July 10, 2018.
- "IUGS ratifies Holocene". Retrieved 18 August 2018.
- "announcement ICS chart v2018/07". Retrieved 9 August 2018.
- Cohen, Kim Mikkel, David A. T. Harper, Philip Leonard Gibbard, and Junxuan Fan. "The ICS International Chronostratigraphic Chart". International Commission on Stratigraphy. Retrieved 19 July 2018.
- International Commission on Stratigraphy. "ICS chart containing the Quaternary and Cambrian GSSPs and new stages (v 2018/07) is now released!". Retrieved 19 July 2018.
- Amos, Jonathan (18 July 2018). "Welcome to the Meghalayan Age - a new phase in history". BBC News. Retrieved 19 July 2018.
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