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Late Ordovician

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Third and final epoch of the Ordovician Period, 458–444 million years ago

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Late/Upper Ordovician

458.2 ± 0.7 – 443.1 ± 0.9Ma

PreꞒ

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A map of Earth as it appeared 450 million years ago during the Late Ordovician Epoch, Katian Age

Chronology

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Firstland plant spores^[1]

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Ordovician meteor event^[2]^[3]

Subdivision of the Ordovician according to theICS, as of 2024.^[4]
Vertical axis scale:Millions of years ago

Etymology

Name formality

Formal

Usage information

Celestial body

Earth

Regional usage

Global (ICS)

Time scale(s) used

ICS Time Scale

Definition

Chronological unit

Epoch

Stratigraphic unit

Series

Time span formality

Formal

TheLate Ordovician is the third and final epoch of theOrdovician period, lasting 15.1 million years and spanning from around 458.2 to 443.1 million years ago.^[4]^[5] The rocks associated with this epoch are referred to as theUpper Ordovician Series.

At this time,Western andCentral Europe andNorth America collided to formLaurentia, while glaciers built up inGondwana, which was positioned over theSouth Pole. This caused a drop in global temperatures, resulting in "ice house" conditions.^[6]

For most of this time, life continued to flourish, but at and near the end of the period, there weremass-extinction events that seriously affectedplanktonic forms likeconodonts,graptolites, and some groups oftrilobites (Agnostida andPytchopariida, which completely died out, and theAsaphida which were much reduced).Brachiopods,bryozoans andechinoderms were also heavily affected, and theendocerid cephalopods died out completely, except for possible rareSilurian forms. The Ordovician-Silurian Extinction Events may have been caused by an ice age that occurred at the end of the Ordovician period as the end of the Late Ordovician was one of the coldest times in the last 600 million years of Earth history.

References

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^Wellman, C.H.; Gray, J. (2000)."The microfossil record of early land plants".Phil. Trans. R. Soc. B.355 (1398):717–732.doi:10.1098/rstb.2000.0612.PMC 1692785.PMID 10905606.
^Korochantseva, Ekaterina; Trieloff, Mario; Lorenz, Cyrill; Buykin, Alexey; Ivanova, Marina; Schwarz, Winfried; Hopp, Jens; Jessberger, Elmar (2007). "L-chondrite asteroid breakup tied to Ordovician meteorite shower by multiple isochron 40 Ar- 39 Ar dating".Meteoritics & Planetary Science.42 (1):113–130.Bibcode:2007M&PS...42..113K.doi:10.1111/j.1945-5100.2007.tb00221.x.
^Lindskog, A.; Costa, M. M.; Rasmussen, C.M.Ø.; Connelly, J. N.; Eriksson, M. E. (2017-01-24)."Refined Ordovician timescale reveals no link between asteroid breakup and biodiversification".Nature Communications.8 14066.doi:10.1038/ncomms14066.ISSN 2041-1723.PMC 5286199.PMID 28117834.It has been suggested that the Middle Ordovician meteorite bombardment played a crucial role in the Great Ordovician Biodiversification Event, but this study shows that the two phenomena were unrelated
^^a ^b"International Chronostratigraphic Chart"(PDF).International Commission on Stratigraphy. December 2024. RetrievedOctober 23, 2025.
^Hambrey, M.J. (October 1985)."The late Ordovician—Early Silurian glacial period".Palaeogeography, Palaeoclimatology, Palaeoecology.51 (1–4):273–289.doi:10.1016/0031-0182(85)90089-6.
^Buggisch, Werner; Joachimski, Michael M.; Lehnert, Oliver; Bergström, Stig M.; Repetski, John E.; Webers, Gerald F. (2009)."Did intense volcanism trigger the first Late Ordovician icehouse?".Geology.38 (4):327–330.doi:10.1130/G30577.1.ISSN 1943-2682.

External links

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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)