Holocene

Dates are relative to the year 2000 (eg. Greenlandian began 8,333 years before 2000), except for the Meghalayan which began 4,200 years BP ie. before 1950.

'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.

The Holocene ( /ˈhɒləˌsn, ˈh-/)[2][3] is the current geological epoch. It began approximately 11,650 cal years before present, after the last glacial period.[4] The Holocene and the preceding Pleistocene[5] together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1, and is considered by some to be an interglacial period.

The Holocene has seen the growth and impacts of the human species worldwide, including all its written history, development of major civilizations, and overall significant transition toward urban living in the present. Human impacts on modern-era Earth and its ecosystems may be considered of global significance for future evolution of living species, including approximately synchronous lithospheric evidence, or more recently hydrospheric and atmospheric evidence of human impacts. In July 2018, International Union of Geological Sciences split Holocene into three distinct subsections, Greenlandian (11,700 years ago to (8,326 years ago), Northgrippian (8,326 years ago to 4,200 years ago) and Meghalayan (4,200 years ago to the present), as proposed by International Commission on Stratigraphy.[6] The boundary stratotype of Meghalayan is a speleothem in Mawmluh cave in India,[7] and the global auxiliary stratotype is an ice core from Mount Logan in Canada.[8]

The name Holocene comes from the Ancient Greek words ὅλος (holos, whole or entire) and καινός (kainos, new), meaning "entirely recent".[9][10]

It is accepted by the International Commission on Stratigraphy that the Holocene started approximately 11,650 cal years BP.[4] The Subcommission on Quaternary Stratigraphy quotes Gibbard and van Kolfschoten in Gradstein Ogg and Smith in stating the term 'Recent' as an alternative to Holocene is invalid and should not be used and also observe that the term Flandrian, derived from marine transgression sediments on the Flanders coast of Belgium has been used as a synonym for Holocene by authors who consider the last 10,000 years should have the same stage-status as previous interglacial events and thus be included in the Pleistocene.[11] The International Commission on Stratigraphy, however, considers the Holocene an epoch following the Pleistocene and specifically the last glacial period. Local names for the last glacial period include the Wisconsinan in North America,[12] the Weichselian in Europe,[13] the Devensian in Britain,[14] the Llanquihue in Chile[15] and the Otiran in New Zealand.[16]

The Holocene can be subdivided into five time intervals, or chronozones, based on climatic fluctuations:[17]

This page was last edited on 19 July 2018, at 05:54 (UTC).
Reference: https://en.wikipedia.org/wiki/Holocene under CC BY-SA license.

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