Wikiwand AI

Sheinwoodian

Age on the geologic timescale From Wikipedia, the free encyclopedia

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 432.9 ± 1.2 Ma and 430.6 ± 1.3 Ma (million years ago), approximately. The Sheinwoodian Age succeeds the Telychian Age and precedes the Homerian Age.[5]

Name formalityFormal
Name ratified1980[4]
Celestial bodyEarth
Regional usageGlobal (ICS)
Quick facts Chronology, Etymology ...
Sheinwoodian
432.9 ± 1.2 – 430.6 ± 1.3 Ma
Paleogeography of the late Sheinwoodian
Chronology
−444 —
–
−442 —
–
−440 —
–
−438 —
–
−436 —
–
−434 —
–
−432 —
–
−430 —
–
−428 —
–
−426 —
–
−424 —
–
−422 —
–
−420 —
–
Paleozoic
 
 
 
←
←
←
Subdivision of the Silurian according to the ICS, as of 2024.[3]
Vertical axis scale: Millions of years ago
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 definitionImprecise. Currently placed between acritarch biozone 5 and LAD of Pterospathodus amorphognathoides. See Llandovery for more info.
Lower boundary definition candidatesA conodont boundary (Ireviken datum 2) which is close to the murchisoni graptolite biozone.
Lower boundary GSSP candidate section(s)None
Lower boundary GSSPHughley Brook, Apedale, UK
52.5811°N 2.6389°W / 52.5811; -2.6389
Lower GSSP ratified1980[4]
Upper boundary definitionFAD of the graptolite Cyrtograptus lundgreni
Upper boundary GSSPSheinton Brook, Homer, England
52.6156°N 2.5647°W / 52.6156; -2.5647
Upper GSSP ratified1980[4]
Close

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

Related Articles

Timelines

Top Qs

Fact Checks