View source for Template:Period start

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<!-- We can also include notable dates which are subject to change, e.g. Burgess shale-->
|burgess shale|mid middle cambrian<!--Mid middle is approximate; cf. Burgess Shale-->=505
|chengjiang=524
|sirius passet=525
|doushantou=570

|hadean|precambrian=4600
|archean
 |eoarchean|isuan=4000
 |paleoarchean|palaeoarchean=3600
 |mesoarchean=3200
 |neoarchean=2800
|proterozoic
 |paleoproterozoic|palaeoproterozoic
  |siderian=2500
  |rhyacian=2300
  |orosirian=2050
  |statherian=1800
 |mesoproterozoic
  |calymmian=1600
  | riphean|ectasian=1400
  | stenian=1200
 |neoproterozoic
  |tonian=1000
  | cryogenian|baikalian=850 
  | ediacaran|vendian=635
  | mayanian=1100
  | sinian|sturtian=1050
|phanerozoic
 |paleozoic
  |cambrian
   |earliest cambrian|early cambrian|lower cambrian|terreneuvian|fortunian|manykaian|nemakit-daldynian=541.0
   |caerfai|tommotian=530
   |cambrian stage 2=529
   |atdabanian|series 2|cambrian series 2|stage 3|cambrian stage 3|mid early cambrian|middle early cambrian=521
   |botomian=522
   |toyonian|late early cambrian|upper early cambrian|upper lower cambrian=516
   |cambrian stage 4|stage 4=514
   |middle cambrian|early middle cambrian|mid cambrian|series 3|cambrian series 3|cambrian stage 5|stage 5|st davids=509
   |drumian=504.5
   |guzhangian|nganasanian|mindyallan=500.5
   |merioneth|furongian=497
   |late cambrian|upper cambrian|paibian|franconian<!--unofficial and approximate!-->=497
   |upper upper cambrian|late late cambrian|mansian=490<!--Arbritary number.-->
      | ordovician|early ordovician|lower ordovician|tremadocian=485.4
      | late early ordovician=479
      | arenig|floian=477.7
      |dapingian|middle ordovician|mid ordovician|ordovician iii|early middle ordovician=470.0
      | darriwilian=467.3
      |late ordovician|upper ordovician|ordovician v|sandbian|early late ordovician=458.4
      | ordovician vi|katian=453.0
      | hirnantian=445.2
      | middle late ordovician=455
      | silurian|early silurian|lower silurian|llandovery|rhuddanian=443.4
        |aeronian=440.8
        |telychian=438.5
      | wenlock|sheinwoodian=433.4
      |homerian=430.5
      |late silurian|upper silurian|ludlow|gorstian=427.4
      |ludfordian=425.6
      | pridoli|unnamed pridoli stage=423.0
        | devonian|early devonian|lower devonian|lochkovian|downtonian<!--approx-->=419.2
      | pragian|praghian=410.8
        | emsian=407.6
      |middle devonian|mid devonian|eifelian=393.3
      | givetian=387.7
      |late devonian|upper devonian|frasnian=382.7
      | famennian=372.2
      | early carboniferous|lower carboniferous|carboniferous|mississippian|early mississippian|lower mississippian|tournaisian=358.9
      | middle mississippian|visean=346.7
      | late mississippian|serpukhovian=330.9
      | namurian=326
      | upper carboniferous|late carboniferous|pennsylvanian|early pennsylvanian|lower pennsylvanian|bashkirian=323.2
      | westphalian = 313
      | middle pennsylvanian|moscovian=315.2
        | late pennsylvanian|kasimovian=307.0
      |stephanian=304
      |gzhelian=303.7
        | permian|early permian|lower permian|cisuralian|asselian=298.9
      | sakmarian=295.0<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
      | artinskian=290.1
      | kungurian=283.5<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
      | guadalupian=272.3
      |middle permian|mid permian|roadian|ufimian=272.3
        | wordian=268.8
      | capitanian=265.1
      |late permian|upper permian|lopingian|wuchiapingian|longtanian=259.8<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
      | changhsingian=254.14<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
        |mesozoic|triassic|early triassic|lower triassic|induan=252.17<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
      | olenekian|spathian=251.2
        |middle triassic|mid triassic|anisian=247.2
          | ladinian=242
          |late triassic|upper triassic|carnian=237<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
        | norian=227<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
      | rhaetian=208.5
      | jurassic|early jurassic|lower jurassic|hettangian=201.3
        | sinemurian=199.3
      | pliensbachian=190.8
        | toarcian=182.7
        |middle jurassic|mid jurassic|aalenian=174.1
        | bajocian=170.3
      | bathonian=168.3
        | callovian=166.1
        |late jurassic|upper jurassic|oxfordian=163.5
        | kimmeridgian=157.3
        | tithonian=152.1
        | cretaceous|early cretaceous|lower cretaceous|berriasian|neocomian=145.0
        | valanginian=139.8
        | hauterivian=132.9<!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
        | barremian|gallic=129.4
          | aptian=125.0
          | albian=113.0
       |late cretaceous|upper cretaceous|cenomanian=100.5
       | turonian=93.9
         | coniacian|senonian=89.8
       | santonian=86.3
       | campanian=83.6
       | maastrichtian=72.1
       |cenozoic|paleogene|paleocene|early paleocene|lower paleocene|tertiary|danian=66.0
       | puercan=65
       | torrejonian=63.3
       | middle paleocene|selandian=61.6
       | tiffanian=60.2
       | late paleocene|thanetian=59.2
       | clarkforkian=56.8
       |eocene|early eocene|lower eocene|ypresian|mp 10=56.0
       |wasatchian=55.4
       |bridgerian=50.3
       | middle eocene|lutetian|mp 11=47.8
       |uintan=46.2
       |duchesnean=42
       |bartonian=41.3
       |chadronian=38
       | late eocene|priabonian=38.0
       |oligocene|early oligocene|lower oligocene|rupelian|orellan=33.9
       |whitneyan=33.3
       |arikeean=30.6
       | late oligocene|chattian=28.1
     | neogene|miocene|early miocene|lower miocene|aquitanian=23.03
     |hemingfordian=20.6
     |burdigalian=20.44
     |barstovian=16.3
     | middle miocene|langhian=15.97
     |serravallian=13.82
     |clarendonian=13.6
   | late miocene|tortonian=11.62
     |hemphillian=10.3
    |messinian=7.246
    |pliocene|early pliocene|lower pliocene|zanclean=5.333
    |blancan=4.75
      | late pliocene|piacenzian=3.600
    |pleistocene|early pleistocene|lower pleistocene|gelasian=2.58 <!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
    |calabrian=1.80 <!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->
    |irvingtonian=1.8
    | middle pleistocene=0.781
    |rancholabrean=.24
    | late pleistocene=0.126

|quaternary=2.58 <!-- according to http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg-->

|holocene=0.0117



|now|recent|present|current=0}} round {{{2|5}}}}}</includeonly><noinclude>{{documentation}}</noinclude>