Homerian
In the geologic timescale, the Homerian is the age of the Wenlock epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 430.5 ± 0.7 Ma and 427.4 ± 0.5 Ma (million years ago), approximately. The Homerian age succeeds the Sheinwoodian age and precedes the Gorstian age.
Homerian | |
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430.5 ± 0.7 – 427.4 ± 0.5 Ma | |
Chronology | |
Epochs in the Silurian -444 — – -442 — – -440 — – -438 — – -436 — – -434 — – -432 — – -430 — – -428 — – -426 — – -424 — – -422 — – -420 — – -418 — Epochs of the Silurian Period. Axis scale: millions of years ago. | |
Etymology | |
Name formality | Formal |
Name ratified | 1980[3] |
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 | FAD of the Graptolite Cyrtograptus lundgreni |
Lower boundary GSSP | Sheinton Brook, Homer, England 52.6156°N 2.5647°W |
GSSP ratified | 1980[3] |
Upper boundary definition | FAD of the Graptolite Saetograptus (Colonograptus) varians |
Upper boundary GSSP | Pitch Coppice, Ludlow, U.K. 52.3592°N 2.7772°W |
GSSP ratified | 1980[3] |
The name comes from the small village of Homer, Shropshire near Much Wenlock.[4]
Palaeontology
Arthropods
Arthropods of the Homerian | |||||
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Taxa | Presence | Location | Description | Images | |
Balizoma | 440.8 million years ago to Pridoli epoch | Dudley, England | only been found in rocks of Silurian age. | ||
Cephalopods
Cephalopods of the Homerian | ||||
---|---|---|---|---|
Taxa | Presence | Location | Description | Images |
Dapingian-Homerian | ||||
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.
- 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.
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