Sheinwoodian
Sheinwoodian | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
433.4 ± 0.8 – 430.5 ± 0.7 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓ | |||||||||||||
Paleogeography of the late Sheinwoodian | |||||||||||||
Chronology | |||||||||||||
| |||||||||||||
Etymology | |||||||||||||
Name formality | Formal | ||||||||||||
Name ratified | 1980[4] | ||||||||||||
Usage information | |||||||||||||
Celestial body | Earth | ||||||||||||
Regional usage | Global (ICS) | ||||||||||||
Time scale(s) used | ICS Time Scale | ||||||||||||
Definition | |||||||||||||
Chronological unit | Age | ||||||||||||
Stratigraphic unit | Stage | ||||||||||||
Time span formality | Formal | ||||||||||||
Lower boundary definition | Imprecise. Currently placed between acritarch biozone 5 and LAD of Pterospathodus amorphognathoides. See Llandovery for more info. | ||||||||||||
Lower boundary definition candidates | A conodont boundary (Ireviken datum 2) which is close to the murchisoni graptolite biozone. | ||||||||||||
Lower boundary GSSP candidate section(s) | None | ||||||||||||
Lower boundary GSSP | Hughley Brook, Apedale, UK 52°34′52″N 2°38′20″W / 52.5811°N 2.6389°W / 52.5811; -2.6389 | ||||||||||||
Lower GSSP ratified | 1980[4] | ||||||||||||
Upper boundary definition | FAD of the graptolite Cyrtograptus lundgreni | ||||||||||||
Upper boundary GSSP | Sheinton Brook, Homer, England 52°36′56″N 2°33′53″W / 52.6156°N 2.5647°W / 52.6156; -2.5647 | ||||||||||||
Upper GSSP ratified | 1980[4] |
In the geologic timescale, the Sheinwoodian is the age of the Wenlock Epoch of the Silurian Period of the Paleozoic Era of the Phanerozoic Eon that is comprehended between 433.4 ± 0.8 Ma and 430.5 ± 0.7 Ma (million years ago), approximately. The Sheinwoodian Age succeeds the Telychian Age and precedes the Homerian Age.[5]
Definition
The Wenlock-Llandovery boundary is defined by the first occurrence of Cyrtograptus centrifugus. The stage is named after Sheinwood village, north of Much Wenlock. The Buildwas Formation of Shropshire, United Kingdom contains the type section.[6]
References
- ^ Jeppsson, L.; Calner, M. (2007). "The Silurian Mulde Event and a scenario for secundo—secundo events". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 93 (02): 135–154. doi:10.1017/S0263593300000377.
- ^ Munnecke, A.; Samtleben, C.; Bickert, T. (2003). "The Ireviken Event in the lower Silurian of Gotland, Sweden-relation to similar Palaeozoic and Proterozoic events". Palaeogeography, Palaeoclimatology, Palaeoecology. 195 (1): 99–124. doi:10.1016/S0031-0182(03)00304-3.
- ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
- ^ a b c Holland, C. (1982). "The State of Silurian Stratigraphy" (PDF). Episodes. 1982: 21–23. Retrieved 11 December 2020.
- ^ Gradstein, Felix M.; Ogg, James G.; Smith, Alan G. (2004). A Geologic Time Scale 2004. ISBN 9780521786737.
- ^ Silurian System
- v
- t
- e
(present–66.0 Ma)
Quaternary (present–2.58 Ma) | |
---|---|
Neogene (2.58–23.0 Ma) | |
Paleogene (23.0–66.0 Ma) |
(66.0–252 Ma)
Cretaceous (66.0–145 Ma) | |
---|---|
Jurassic (145–201 Ma) | |
Triassic (201–252 Ma) |
(252–539 Ma)
Permian (252–299 Ma) | |
---|---|
Carboniferous (299–359 Ma) |
|
Devonian (359–419 Ma) | |
Silurian (419–444 Ma) | |
Ordovician (444–485 Ma) | |
Cambrian (485–539 Ma) |
(539 Ma–2.5 Ga)
Neoproterozoic (539 Ma–1 Ga) | |
---|---|
Mesoproterozoic (1–1.6 Ga) | |
Paleoproterozoic (1.6–2.5 Ga) |
ka = kiloannum (thousands years ago); Ma = megaannum (millions years ago); Ga = gigaannum (billions years ago).
See also: Geologic time scale • Geology portal • World portal
See also: Geologic time scale • Geology portal • World portal
This geochronology article is a stub. You can help Wikipedia by expanding it. |
- v
- t
- e