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Silurian

The Silurian (/sɪˈljʊəri.ən, saɪ-/ sih-LURE-ee-ən, sy-) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at 443.1 Ma (million years ago) to the beginning of the Devonian Period, 419.62 Ma. The Silurian is the third and shortest period of the Paleozoic Era, and the third of twelve periods of the…

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Celestial body
Earth
Chronological unit
Period
First proposed by
Roderick Murchison, 1835
Lower boundary definition
FAD of the Graptolite Akidograptus ascensus
Lower GSSP ratified
1984
Name formality
Formal

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Overview

History of study

Paleogeography

Climate and sea level

Flora and fauna

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Silurian

Nodes152
Edges151
Triples147
Avg. degree1.99
Density0.013158
Components1

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Silurian

Top relations

related to history · 35
Silurian → Adam Sedgwick, An, As, Baltic, British, Caer Caradoc, Cambrian, Cambrian Systems, Celtic, Charles Lapworth, England, Exhibiting, Geologic, Gotland, Gotlandian, He, In, Latin, Map, Murchison
related to References · 35
Silurian → Anderson, Bibcode, Braddy, Briggs, Cambridge University Press, Cesare, Chelicerata, Cosmology, DEG, DEG Briggs, DG, Emiliani, Environment, Evolution, Geology, Journal, Kluessendorf, Late Llandovery, LI, Life
related to External links · 22
Silurian → Archived, Chronostratography, Devonian Rocks, Examples, Geologic Time Scale, Global Boundary Stratotype Sections, GSSP's, ICS, International Commission, Jim, June, Ogg, Overview, Palaeos, Points, Retrieved September, Silurian FossilsGeoWhen Database, SilurianSilurian, SilurianUCMP Berkeley, Stratigraphy
related to Climate and sea level · 11
Silurian → CO2, Devonian, During, Early, Earth, Hirnantian, Layers, Ordovician, Sea, South Pole, The Silurian
related to Flora and fauna · 9
Silurian → Cambrian, Devonian, Earth, However, Late Ordovician, LOME, Ordovician, Silurian-Devonian Terrestrial Revolution, The Silurian
related to Paleogeography · 9
Silurian → Avalonia, Baltica, During, Euramerica, Gondwana, Laurentia, Ordovician, The, With
related to Perturbations · 5
Silurian → Each, Lau, Mulde, The, The Ireviken
Celestial body · 1
Silurian → Earth
Chronological unit · 1
Silurian → Period
First proposed by · 1
Silurian → Roderick Murchison, 1835

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Important terminology

period ordovician fossils devonian first sea known strata years early ma earth new scale geologic event system cambrian brachiopods ago

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
SilurianCelestial bodyEarth1.00infobox
SilurianChronological unitPeriod1.00infobox
SilurianFirst proposed byRoderick Murchison, 18351.00infobox
SilurianLower boundary definitionFAD of the Graptolite Akidograptus ascensus1.00infobox
SilurianLower boundary GSSPDob's Linn, Moffat, United Kingdom .mw-parser-output .geo-default,.mw-parser-output .geo-dms,.mw-parser-output .geo-dec{display:inline}.mw-parser-output .geo-nondefault,.mw-pars…1.00infobox
SilurianLower GSSP ratified19841.00infobox
SilurianName formalityFormal1.00infobox
SilurianRegional usageGlobal (ICS)1.00infobox
SilurianSea level above present dayAround 180 m, with short-term negative excursions1.00infobox
SilurianStratigraphic unitSystem1.00infobox
SilurianSynonym(s)Gotlandian1.00infobox
SilurianTime scale(s) usedICS Time Scale1.00infobox
SilurianTime span formalityFormal1.00infobox
SilurianUpper boundary definitionFAD of the Graptolite Monograptus uniformis1.00infobox
SilurianUpper boundary GSSPKlonk, Czech Republic 49°51′18″N 13°47′31″E / 49.8550°N 13.7920°E / 49.8550; 13.79201.00infobox
SilurianUpper GSSP ratified19721.00infobox
Silurianis athird and shortest period of the Paleozoic Era0.90text

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