Timeline of Geologic Eons, Eras, Periods and Epochs

Geologic Time:

NOTE: Names and ages vary from source to source, this is a synthesis. For example, the Hadean, Archean and Proterozoic Eons were once all just called "Precambrian" -- a term still sometimes encountered, along with the ill-defined "Protocambrian" and "Eocambrian".

    EONS
  • Hadean Eon 4.5 to 3.8 Billion Years Ago
  • Archean Eon 3.8 to 2.5 Billion Years Ago
      ERAS
    • Paleoarchean 3.8 to 3.3 Billion Years Ago
    • Mesoarchean 3.3 to 2.9 Billion Years Ago
    • Neoarchean 2.9 to 2.5 Billion Years Ago
  • Proterozoic Eon 2.5 Billion to 570 Million Years Ago
      ERAS
    • Paleoproterozoic 2.5 Billion to 1.6 Billion Years Ago
    • Mesoproterozoic 1.6 Billion to 900 Million Years Ago
    • Neoproterozoic 900 to 570 Million Years Ago
        Periods
      • Not clearly defined yet, terms like Ediacaran (or Ediacarian), Vendian, Verangian are used.
  • Phanerozoic Eon 570 Million Years Ago to Present
      ERAS
    • Paleozoic 570 to 245 Million Years Ago
        Periods
      • Cambrian 544 to 490 Million Years Ago
          EPOCHS
        • Early Cambrian 544 to 510 Million Years Ago
            AGES
          • Manykaian (or Nemakit-Daldynian) 544 to 530 Million Years Ago
          • Tommotian 530 to 525 Million Years Ago
          • Atdbanian 525 to 520 Million Years Ago
          • Botomian (or Toyonian or Lenian) 520 to 510 Million Years Ago
        • Middle Cambrian 510 to 500 Million Years Ago
            AGE
          • Solvan (or Manevian)
        • Late Cambrian 500 to 490 Million Years Ago
            AGES
          • Dresbachian (or Maentwrogian)
          • Franconian (or Dolgellian)
          • Trempealeauan
      • Ordovician 490 to 440 Million Years Ago
          Epochs
        • Early Ordovician
            AGES
          • Tremadocian 490 to 485 Million Years Ago
          • Arenigian 485 to 478 Million Years Ago
        • Middle Ordovician
            AGES
          • Llanvirnian 478 to 468 Million Years Ago
          • Llandeilian 468 to 458 Million Years Ago
        • Late Ordovician
            AGES
          • Caradocian 458 to 448 Million Years Ago
          • Ashgillian 448 to 440 Million Years Ago
      • Silurian 440 to 410 Million Years Ago
          EPOCHS
        • Early Silurian
            AGES
          • Llandoverian 440 to 428 Million Years Ago
          • Wenlockian 428 to 421 Million Years Ago
        • Late Silurian
            AGES
          • Ludlovian 421 to 414 Million Years Ago
          • Pridolian 414 to 410 Million Years Ago
      • Devonian 410 to 360 Million Years Ago
          EPOCHS
        • Early Devonian
            AGES
          • Gedinnian 410 to 401 Million Years Ago
          • Siegenian 401 to 394 Million Years Ago
          • Emsian 394 to 387 Million Years Ago
        • Middle Devonian
            AGES
          • Eifelian 387 to 380 Million Years Ago
          • Givetian 380 to 374 Million Years Ago
        • Late Devonian
            AGES
          • Frasnian 374 to 367 Million Years Ago
          • Famennian 367 to 360 Million Years Ago
      • Carboniferous
          EPOCHS
        • Mississippian 360 to 325 Million Years Ago (called Lower or Early Carboniferous in Europe)
            AGES
          • Tournaisian 360 to 352 Million Years Ago
          • Visean 352 to 333 Million Years Ago
          • Serpukhovian 333 to 325 Million Years Ago
        • Pennsylvanian 325 to 286 Million Years Ago (called Middle and Late, or Middle and Upper Carboniferous in Europe)
            AGES
          • Bashkirian (approximates Namurian?) 325 to 308 Million Years Ago
          • Moscovian (or Westphalian) 308 to 294 Million Years Ago
          • Kasimovian (or Gzelian or Stephanian) 294 to 286 Million Years Ago
      • Permian 286 to 245 Million Years Ago
          EPOCHS
        • Early Permian
            AGES
          • Asselian 286 to 279 Million Years Ago
          • Sakmarian 279 to 268 Million Years Ago
          • Artinskian 268 to 263 Million Years Ago
        • Late Permian
            AGES
          • Kungurian 263 to 258 Million Years Ago (sometimes considered Early Permian)
          • Kazanian (or Ufimian) 258 to 253 Million Years Ago
          • Tatarian 253 to 245 Million Years Ago
      ERAS
    • Mesozoic 245 to 65 Million Years Ago
        Periods
      • Triassic 245 to 208 Million Years Ago
          EPOCHS
        • Early Triassic
            AGE
          • Scythian 245 to 240 Million Years Ago
        • Middle Triassic
            AGES
          • Anisian 240 to 235 Million Years Ago
          • Ladinian 235 to 230 Million Years Ago
        • Late Triassic
            AGES
          • Carnian 230 to 225 Million Years Ago
          • Norian 225 to 208 Million Years Ago
      • Jurassic 208 to 146 Million Years Ago
          EPOCHS
        • Early Jurassic
            AGES
          • Hettangian 208 to 204 Million Years Ago
          • Sinemurian 204 to 198 Million Years Ago
          • Pliensbachian 198 to 193 Million Years Ago
          • Toarcian 193 to 187 Million Years Ago
        • Middle Jurassic
            AGES
          • Aalenian 187 to 183 Million Years Ago
          • Bajocian 183 to 176 Million Years Ago
          • Bathonian 176 to 169 Million Years Ago
          • Callovian 169 to 163 Million Years Ago
        • Late Jurassic
            AGES
          • Oxfordian 163 to 156 Million Years Ago
          • Kimmeridgian 156 to 152 Million Years Ago
          • Tithonian 152 to 144 Million Years Ago
      • Cretaceous 146 to 65 Million Years Ago
          EPOCHS
        • Early Cretaceous
            AGES
          • Berriasian 144 to 138 Million Years Ago
          • Valanginian 138 to 131 Million Years Ago
          • Hauterivian 131 to 124 Million Years Ago
          • Barremian 124 to 119 Million Years Ago
          • Aptian 119 to 113 Million Years Ago
          • Albian 113 to 97.5 Million Years Ago
        • Late Cretaceous
            AGES
          • Cenomanian (sometimes included with Early Cretaceous) 97.5 to 91 Million Years Ago
          • Turonian 91 to 88.5 Million Years Ago
          • Coniacian 88.5 to 87.5 Million Years Ago
          • Santonian 87.5 to 84 Million Years Ago
          • Campanian 84 to 74.5 Million Years Ago
          • Maastrichtian 74.5 to 66.4 Million Years Ago
      ERAS
    • Neozoic (also called Cenozoic) 66.4 Million Years Ago to Present
        Periods
      • Tertiary 65 to 1.8 Million Years Ago
          Epochs
        • Paleocene (first epoch of the Paleogene) 65 to 54 Million Years Ago
            AGES
          • Danian 66.4 to 63.6 Million Years Ago
          • Selandian 63.6 to 57.8 Million Years Ago
        • Eocene (second epoch of the Paleogene) 57.8 to 36.6 Million Years Ago
            AGES
          • Ypresian 57.8 to 52 Million Years Ago
          • Lutetian 52 to 43.6 Million Years Ago
          • Bartonian 43.6 to 40 Million Years Ago
          • Priabonian 40 to 36.6 Million Years Ago
        • Oligocene (last epoch of the Paleogene) 36.6 to 23.7 Million Years Ago
            AGES
          • Rupelian 36.6 to 30 Million Years Ago
          • Chattian 30 to 23.7 Million Years Ago
        • Miocene (first epoch of the Neogene) 23.7 to 5.3 Million Years Ago
            AGES
          • Aquitanian 23.7 to 21.5 Million Years Ago
          • Burdigalian 21.5 to 16.6 Million Years Ago
          • Langhian 16.6 to 15.1 Million Years Ago
          • Serravalian 15.1 to 11.2 Million Years Ago
          • Tortonian 11.2 to 6.5 Million Years Ago
          • Messinian 6.5 to 5.3 Million Years Ago
        • Pliocene (last epoch of the Neogene) 5.3 to 1.6 Million Years Ago
            AGES
          • Zanclean 5.3 to 3.4 Million Years Ago
          • Piacenzian 3.4 to 1.6 Million Years Ago
      • Quaternary 1.6 Million Years Ago to Present
          Epochs
        • Pleistocene 1.6 Million Years Ago to 11 Thousand Years ago
            AGE
          • Calabrian
        • Holocene 11 Thousand Years Ago to 1950
        • Anthropocene 1950 to present



© 2004 - 2016 by Andrew J. Morris -- www.ajmorris.com
All Rights Reserved.





Bookshelf
Science Notes
Science in the News
AJM DotCom Home