Rhyacian
Rhyacian | ||||||||||||||||
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![]() A reconstruction of the Earth as it may have appeared at the end of the Rhyacian Period, 2050 million years ago. | ||||||||||||||||
Chronology | ||||||||||||||||
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Etymology | ||||||||||||||||
Name formality | Formal | |||||||||||||||
Usage information | ||||||||||||||||
Celestial body | Period | |||||||||||||||
Stratigraphic unit | System | |||||||||||||||
Time span formality | Formal | |||||||||||||||
Lower boundary definition | Defined Chronometrically | |||||||||||||||
Lower GSSA ratified | 1991[1] | |||||||||||||||
Upper boundary definition | Defined Chronometrically | |||||||||||||||
Upper GSSA ratified | 1991[1] |
The Rhyacian Period ( Era and lasted from 2300 Mya to 2050 Mya (million years ago).[2] Instead of being based on stratigraphy, these dates are defined chronometrically.[3]
The
The Huronian (Makganyene) global glaciation began at the start of the Rhyacian and lasted 100 million years. It lasted about 80% of this period.[4]
For the time interval from 2250 Ma to 2060 Ma, an alternative period based on stratigraphy rather than chronometry, named either the Jatulian or the Eukaryian, was suggested in the geological timescale review 2012 edited by Gradstein et al.,IUGS. The term Jatulian is, however, used in the regional stratigraphy of the Paleoproterozoic rocks of Fennoscandia.[6]
This is when the
eukaryotes are thought to have originated from the symbiosis between asgardarchaea and alphaproteobacteria, as well as the sexual reproduction found within the eukaryotes only, thus the alternative name Eukaryian.[7][8][9]
References
- ^ .
- ^ "Rhyacian Period". GeoWhen Database. Archived from the original on August 19, 2006. Retrieved January 5, 2006.
- ^ .
- PMID 16061801.
- ISBN 978-0-44-459390-0.
- .
- PMID 33767194.
- S2CID 212732729.
- ISBN 978-0-44-459425-9.