| 词条 | Preboreal |
| 释义 |
The Preboreal is a stage of the Holocene epoch. It is preceded by the Tarantian and succeeded by the Boreal. It lasted from 10,300 to 9,000{{nbsp}}BP in radiocarbon years or 8350{{nbsp}}BC to 7050{{nbsp}}BC in Gregorian calendar years (8th millennium BC). It is the first stage of the Holocene epoch. The Holocene has not been formally divided by the IUGS. As a result the Preboreal is only a proposal, and as stratigraphy and dating techniques have improved since this 1972 proposal the dates would be different if proposed today. Instead others have begun to use the terms Early, Middle and Late, which strictly should be Lower, Middle and Upper for the Holocene. If this terminology were to be used the preboreal would be replaced by Lower Holocene which would be dated 11.7 - 8.2 ka B2K.[1] In July 2018 the International Commission on Stratigraphy ratified Greenlandian as the globally recognised first age of the Holocene, much overlapping with the North European regional term Preboreal.[2] References1. ^http://www.ub.edu/ice/sites/default/files/docs/jornades/Walker2012.pdf {{Clear}}{{Quaternary Footer}}{{Geological history|p|c}}{{geochronology-stub}}2. ^{{cite web |last1=International Commission on Stratigraphy |title=ICS chart containing the Quaternary and Cambrian GSSPs and new stages (v 2018/07) is now released! |url=http://www.stratigraphy.org/index.php/ics-news-and-meetings/120-ics-chart-containing-the-quaternary-gssps-and-new-stages-v-2018-07-is-now-released |accessdate=15 July 2018}} 2 : Holocene|Geological ages |
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