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TheWenlock Epoch (sometimes referred to as theWenlockian) is the second epoch of theSilurian. It is preceded by theLlandovery Epoch and followed by theLudlow Epoch. Radiometric dates constrain the Wenlockian between 432.9 and 426.7 million years ago.^[5]

Naming and history

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The Wenlock is named afterWenlock Edge, an outcrop of rocks near the town ofMuch Wenlock inShropshire (West Midlands,United Kingdom).^[6] The name was first used in the term "Wenlock andDudley rocks" byRoderick Murchison in 1834 to refer to thelimestones and underlyingshales that underlay what he termed the "Ludlow rocks".^[7] He later modified this term to simply the "Wenlock rocks" in his book,The Silurian System in 1839.^[8]

Definition and subdivision

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The Wenlock's beginning is defined by the lower boundary (orGSSP) of theSheinwoodian. The end is defined as the base (orGSSP) of theGorstian.^[9]

The Wenlock is divided into the olderSheinwoodian and the youngerHomerian stage. The Sheinwoodian lasted from 432.9 to 430.6 million years ago. The Homerian lasted from 430.6 to 426.7 million years ago.^[5]

References

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^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.
^"International Chronostratigraphic Chart"(PDF).International Commission on Stratigraphy. September 2023. RetrievedOctober 23, 2025.
^^a ^b ^cHolland, C. (1982)."The State of Silurian Stratigraphy"(PDF).Episodes.1982:21–23. Retrieved11 December 2020.
^^a ^b"International Chronostratigraphic Chart 2013/01"(PDF). International Commission on Stratigraphy. Retrieved10 July 2013.
^Gradstein, Felix M.; Ogg, James G.; Smith, Alan G. (2004).A Geologic Time Scale 2004.ISBN 9780521786737.
^Murchison R.I. (1833–1834)."On the Structure and Classification of the Transition Rocks of Shropshire, Herefordshire and part of Wales and on the Lines of Disturbance which have affected that Series of Deposits, including the Valley of Elevation of Woolhope".Proceedings of the Geological Society of London.2 (33):14.
^Murchison R.I. (1839).The Silurian System. Murray. p. 208.
^The Geologic Time Scale 2012. Elsevier Science Ltd. 14 August 2012.ISBN 978-0-444-59425-9.

Geological history of Earth

Cenozoic Era
(present–66.0 Ma)

Quaternary(present–2.58 Ma)	Holocene (present–11.7 ka) Pleistocene (11.7 ka–2.58 Ma)
Neogene(2.58–23.0 Ma)	Pliocene (2.59–5.33 Ma) Miocene (5.33–23.0 Ma)
Paleogene(23.0–66.0 Ma)	Oligocene (23.0–33.9 Ma) Eocene (33.9–56.0 Ma) Paleocene (56.0–66.0 Ma)

Mesozoic Era
(66.0–252 Ma)

Cretaceous(66.0–145 Ma)	Late (66.0–100 Ma) Early (100–145 Ma)
Jurassic(145–201 Ma)	Late (145–164 Ma) Middle (164–174 Ma) Early (174–201 Ma)
Triassic(201–252 Ma)	Late (201–237 Ma) Middle (237–247 Ma) Early (247–252 Ma)

Paleozoic Era
(252–539 Ma)

Permian(252–299 Ma)	Lopingian (252–260 Ma) Guadalupian (260–272 Ma) Cisuralian (272–299 Ma)
Carboniferous(299–359 Ma)	Pennsylvanian (299–323 Ma) Mississippian (323–359 Ma)
Devonian(359–419 Ma)	Late (359–383 Ma) Middle (383–393 Ma) Early (393–419 Ma)
Silurian(419–444 Ma)	Pridoli (419–423 Ma) Ludlow (423–427 Ma) Wenlock (427–433 Ma) Llandovery (433–444 Ma)
Ordovician(444–485 Ma)	Late (444–458 Ma) Middle (458–470 Ma) Early (470–485 Ma)
Cambrian(485–539 Ma)	Furongian (485–497 Ma) Miaolingian (497–509 Ma) Series 2 (509–521 Ma) Terreneuvian (521–539 Ma)

Proterozoic Eon
(539 Ma–2.5 Ga)

Neoproterozoic(539 Ma–1 Ga)	Ediacaran (539–635 Ma) Cryogenian (635–720 Ma) Tonian (720 Ma–1 Ga)
Mesoproterozoic(1–1.6 Ga)	Stenian (1–1.2 Ga) Ectasian (1.2–1.4 Ga) Calymmian (1.4–1.6 Ga)
Paleoproterozoic(1.6–2.5 Ga)	Statherian (1.6–1.8 Ga) Orosirian (1.8–2.05 Ga) Rhyacian (2.05–2.3 Ga) Siderian (2.3–2.5 Ga)