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PHANEROZOIC and PRECAMBRIAN CHRONOSTRATIGRAPHY

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PHANEROZOIC and PRECAMBRIAN CHRONOSTRATIGRAPHY PHANEROZOIC and PRECAMBRIAN CHRONOSTRATIGRAPHY Age Series/Epoch Stage/Age Age Series/Epoch Stage/Age Age Erathem/Era System/Period Era Era Eon Eon Eon Ma Period Period System System Erathem Erathem Eonothem Eonothem Eonothem 252.2 ±0.5 541 Holocene Changhsingian Ediacaran 0.0118 Lopingian 254.2 ±0.3 Neo- 635 Upper Wuchiapingian Cryogenian 0.126 259.8 ±0.4 proterozoic 850 “Ionian” Capitanian Tonian Pleistocene 0.781 265.1 ±0.4 1000 Calabrian Guadalupian Wordian Stenian Quaternary 268.8 ±0.5 1.806 Meso- 1200 Gelasian Roadian Ectasian 2.588 272.3 ±0.5 proterozoic 1400 Piacenzian Kungurian Calymmian Pliocene 3.600 Permian 279.3 ±0.6 1600 Zanclean Artinskian Statherian 5.333 Cisuralian 290.1 ±0.2 Proterozoic 1800 Messinian Sakmarian Paleo- Orosirian 7.246 295.5 ±0.4 2050 Tortonian Asselian proterozoic Rhyacian 11.63 298.9 ±0.2 2300 Serravallian Gzhelian Siderian Miocene 13.82 Upper 303.7 ±0.1 2500 Neogene Langhian a l e o z i c P Kasimovian 15.97 307.0 ±0.2 Neoarchean Burdigalian Penn- Middle Moscovian 20.44 sylvanian 315.2 ±0.2 2800 Aquitanian Lower Bashkirian 23.03 323.2 ±0.4 r e c a m b i n P C e n o z i c Mesoarchean Chattian Upper Serpukhovian Oligocene 28.1 330.9 ±0.3 3200 Rupelian Middle Visean 33.9 Carboniferous 346.7 ±0.4 Paleoarchean Missis- sippian Priabonian Lower Tournaisian Archean 37.8 ±0.5 358.9 ±0.4 3600 Bartonian Famennian Eocene 41.2 ±0.5 Upper 372.2 ±1.6 Eoarchean Lutetian Frasnian 47.8 ±0.2 382.7 ±1.6 4000 Ypresian Givetian 56.0 h a n e r o z i c P Paleogene Middle 387.7 ±0.8 Hadean (informal) Thanetian Eifelian 59.2 393.3 ±1.2 ~4560 Paleocene Selandian Emsian 61.6 Devonian 407.6 ±2.6 Units of the international chrono- Danian Lower Pragian 66.0 ±0.05 410.8 ±2.8 stratigraphic scale with estimated Maastrichtian Lochkovian 72.1 ±0.2 419.2 ±3.2 numerical ages from the GTS2012 Campanian Pridoli age model. 83.6 ±0.2 423.0 ±2.3 Santonian Ludfordian Colors are according to the Upper 86.3 ±0.5 Ludlow 425.6 ±0.9 Coniacian Gorstian Commission for the Geological Map 89.8 ±0.3 427.4 ±0.5 of the World. Turonian Homerian 93.9 ±0.2 Wenlock 430.5 ±0.7 Subdivisions of the Phanerozoic are Cenomanian Sheinwoodian 100.5 ±0.4 formally defined by a Global boundary Silurian 433.4 ±0.8 Albian Telychian Stratotype Section and Point (GSSP) at P h a n e r o z i c P 113.0 ±0.4 438.5 ±1.1 Aptian Llandovery Aeronian each lower boundary. Thick yellow lines Cretaceous 126.3 ±0.4 440.8 ±1.2 Barremian Rhuddanian between stages on this diagram denote Lower 130.8 ±0.5 443.8 ±1.5 GSSPs approved by the International Hauterivian Hirnantian 133.9 ±0.6 445.2 ±1.4 Commission on Stratigraphy (ICS) and Valanginian Upper Katian 139.4 ±0.7 453.0 ±0.7 ratified by the International Union Berriasian 145.0 ±0.8 Sandbian of Geological Sciences (IUGS). 458.4 ±0.9 Tithonian Darriwilian Precambrian units are formally defined 152.1 ±0.9 Middle 467.3 ±1.1 Upper Kimmeridgian Dapingian by absolute age (Global Standard 157.3±1.0 Ordovician 470.0 ±1.4 Oxfordian Floian Stratigraphic Age — GSSA), with the 163.5 ±1.1 Lower 477.7 ±1.4 exception of the Ediacaran System Callovian Tremadocian 166.1 ±1.2 485.4 ±1.9 defined by a basal GSSP. Bathonian Stage 10 Middle 168.3 ±1.3 ~ 489.5 Numerical ages assigned to unit M e s o z i c Bajocian Furongian Jiangshanian boundaries are subject to revision upon 170.3 ±1.4 ~ 494 Aalenian Paibian formal decision or revision of GSSPs Jurassic 174.1 ±1.0 ~ 497 Toarcian Guzhangian and when enhanced radio-isotopic and 182.7 ±0.7 ~ 500.5 cyclostratigraphy studies enable Pliensbachian Series 3 Drumian Lower 190.8 ±1.0 ~ 504.5 improvements to the age models. Sinemurian Stage 5 199.3 ±0.3 ~ 509 Stratigraphic information and details Hettangian Cambrian Stage 4 on international and regional geologic 201.3 ±0.2 Series 2 ~ 514 Rhaetian Stage 3 units can be found on the websites of ~ 209.5 ~ 521 Upper Norian Stage 2 the ICS (www.stratigraphy.org) and the ~ 228.4 Terreneuvian ~ 529 Geologic TimeScale Foundation Carnian Fortunian 237.0±1.0 541.0 ±1.0 (https://engineering.purdue.edu/stratigraphy). Ladinian This chart was drafted by Gabi Ogg. Middle 241.5 ±1.0 Triassic Anisian 247.1±0.2 Olenekian Lower 250.0±0.5 Copyright © 2012 Geologic Time Scale Foundation Induan 252.2 ±0.5.
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