In the geologic timescale, the Homerian is an 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
430.5 ± 0.7 – 427.4 ± 0.5 Ma
Paleogeography of the Homerian, 430 Ma
Chronology
Etymology
Name formalityFormal
Name ratified1980[4]
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
Time span formalityFormal
Lower boundary definitionFAD of the graptolite Cyrtograptus lundgreni
Lower boundary GSSPSheinton Brook, Homer, England
52°36′56″N 2°33′53″W / 52.6156°N 2.5647°W / 52.6156; -2.5647
Lower GSSP ratified1980[4]
Upper boundary definitionFAD of the graptolite Saetograptus (Colonograptus) varians
Upper boundary GSSPPitch Coppice, Ludlow, U.K.
52°21′33″N 2°46′38″W / 52.3592°N 2.7772°W / 52.3592; -2.7772
Upper GSSP ratified1980[4]

The name comes from the small village of Homer, Shropshire near Much Wenlock.[5] The defining lower boundary of Homerian rock layers (GSSP) is located within the Coalbrookdale Formation of England.

References edit

  1. ^ 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.
  2. ^ 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.
  3. ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  4. ^ a b c Holland, C. (1982). "The State of Silurian Stratigraphy" (PDF). Episodes. 1982: 21–23. Retrieved 11 December 2020.
  5. ^ Gradstein, Felix M.; Ogg, James G.; Smith, Alan G. (2004). A Geologic Time Scale 2004. ISBN 9780521786737.