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International Stratigraphic Chart

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International Stratigraphic Chart INTERNATIONAL STRATIGRAPHIC CHART ICS International Commission on Stratigraphy Ma Ma Ma Ma Era Era Era Era Eon Age Age Eon Age Age Age Age Eon Age Eon Stage Stage Stage GSSP GSSP GSSP GSSP GSSA Series Epoch Series Epoch Series Epoch Period Period Period Period System System System System Erathem Erathem Erathem Erathem Eonothem Eonothem Eonothem 145.5 ±4.0 Eonothem 359.2 ±2.5 542 Holocene Tithonian Famennian Ediacaran * 0.0115 150.8 ±4.0 Upper 374.5 ±2.6 Neo- ~630 Upper Upper Kimmeridgian Frasnian Cryogenian 0.126 155.7 ±4.0 385.3 ±2.6 proterozoic 850 Pleistocene Middle Oxfordian Givetian Tonian 0.781 161.2 ±4.0 Middle 391.8 ±2.7 1000 Lower Callovian Eifelian Stenian Quaternary 1.806 164.7 ±4.0 397.5 ±2.7 Meso- 1200 Gelasian Bathonian Emsian Ectasian proterozoic 2.588 Middle 167.7 ±3.5 Devonian 407.0 ±2.8 1400 Pliocene Piacenzian Bajocian Lower Pragian Calymmian 3.600 171.6 ±3.0 411.2 ±2.8 1600 Zanclean Aalenian Lochkovian Statherian Jurassic 5.332 175.6 ±2.0 416.0 ±2.8 Proterozoic 1800 Messinian Toarcian Pridoli Paleo- Orosirian 7.246 183.0 ±1.5 418.7 ±2.7 2050 Neogene Tortonian Pliensbachian Ludfordian proterozoic Rhyacian 11.608 Lower 189.6 ±1.5 Ludlow 421.3 ±2.6 2300 Serravallian Sinemurian Gorstian Siderian Miocene 13.65 196.5 ±1.0 422.9 ±2.5 2500 Langhian Hettangian Homerian 15.97 199.6 ±0.6 Wenlock 426.2 ±2.4 Neoarchean M e s o z i c Burdigalian Rhaetian Sheinwoodian r e c a m b i n 20.43 203.6 ±1.5 2800 428.2 ±2.3 P Aquitanian Upper Norian Silurian Telychian 23.03 216.5 ±2.0 436.0 ±1.9 Mesoarchean C e n o z i c Chattian Carnian Llandovery Aeronian Oligocene 28.4 ±0.1 228.0 ±2.0 439.0 ±1.8 3200 Rupelian Ladinian Rhuddanian 33.9 ±0.1 Middle 237.0 ±2.0 443.7 ±1.5 Paleoarchean riassic Priabonian Anisian Archean T Hirnantian 37.2 ±0.1 245.0 ±1.5 a l e o z i c 445.6 ±1.5 3600 P Bartonian Olenekian h a n e r o z i c Upper 40.4 ±0.2 249.7 ±0.7 Eoarchean Lower limit is Eocene Lower P 455.8 ±1.6 Lutetian Induan not defined 48.6 ±0.2 251.0 ±0.4 460.9 ±1.6 h a n e r o z i c Ypresian h a n e r o z i c Changhsingian Darriwilian 55.8 ±0.2 468.1 ±1.6 Subdivisions of the global geologic record are P P Lopingian 253.8 ±0.7 Middle Paleogene Thanetian Wuchiapingian formally defined by their lower boundary. Each unit 58.7 ±0.2 260.4 ±0.7 471.8 ±1.6 of the Phanerozoic interval (~542 Ma to Present) Paleocene Selandian Capitanian Ordovician and the base of the Ediacaran is defined by a Global 61.7 ±0.2 265.8 ±0.7 Lower 478.6 ±1.7 Standard Section and Point (GSSP) at its base, Danian Guadalupian Wordian Tremadocian 65.5 ±0.3 268.0 ±0.7 488.3 ±1.7 whereas the Precambrian Interval is formally Maastrichtian Roadian subdivided by absolute age, Global Standard 70.6 ±0.6 270.6 ±0.7 Furongian Stratigraphic Age (GSSA). Campanian Kungurian Paibian This chart gives an overview of the international 83.5 ±0.7 Permian 275.6 ±0.7 501.0 ±2.0 Santonian Artinskian chronostratigraphic units,their rank, their names Upper 85.8 ±0.7 Cisuralian 284.4 ±0.7 Middle and formal status. These units are approved by the Coniacian Sakmarian International Commission on Stratigraphy (ICS) and 89.3 ±1.0 294.6 ±0.8 513.0 ±2.0 ratified by the International Union of Geological Turonian Asselian Cambrian Sciences (IUGS). 93.5 ±0.8 299.0 ±0.8 Lower The Guidelines of the ICS (Remane et al., 1996, Cenomanian Gzhelian 542.0 ±1.0 99.6 ±0.9 a l e o z i c Upper 303.9 ±0.9 Episodes, 19: 77-81) regulate the selection and Albian P Kasimovian definition of the international units of geologic time. Many GSSP's actually have a 'golden' spike ( ) and Stage 112.0 ±1.0 306.5 ±1.0 and/or System name plaque mounted at the boundary level in the boundary stratotype section, whereas a GSSA is an Aptian Penn- Middle Moscovian Cretaceous abstract age without reference to a specific level in a rock section on Earth. Updated descriptions of each GSSP and 125.0 ±1.0 sylvanian 311.7 ±1.1 M e s o z i c Barremian Lower Bashkirian GSSA are posted on the ICS website (www.stratigraphy.org). Lower 130.0 ±1.5 318.1 ±1.3 Some stages within the Ordovician and Cambrian will be formally named upon international agreement on their Hauterivian Upper Serpukhovian GSSP limits. Most intra-stage boundaries (e.g., Middle and Upper Aptian) are not formally defined. Numerical ages of 136.4 ±2.0 326.4 ±1.6 Valanginian Middle Visean the unit boundaries in the Phanerozoic are subject to revision. Colors are according to the Commission for the 140.2 ±3.0 Carboniferous 345.3 ±2.1 Geological Map of the World (www.cgmw.org). The listed numerical ages are from 'A Geologic Time Scale 2004', by Missis- sippian F.M. Gradstein, J.G. Ogg, A.G. Smith, et al. (2004; Cambridge University Press). Berriasian 145.5 ±4.0 Lower Tournaisian 359.2 ±2.5 This chart was drafted and printed with funding generously provided for the GTS Project 2004 by ExxonMobil, Statoil * proposed by INQUA Norway, ChevronTexaco and BP. The chart was produced by Gabi Ogg. Copyright © 2004 International Commission on Stratigraphy.
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