Sheinwoodian | |||||||||||||
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Chronology | |||||||||||||
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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 | ||||||||||||
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 | ||||||||||||
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]