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Appendix:Geologic timescale

Definition from Dictionary, a free dictionary
When one subtracts from life infancy (which is vegetation), sleep, eating and swilling, buttoning and unbuttoning—how much remains of downright existence? The summer of a dormouse.
Lord Byron
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The eons, eras, periods and epochs of geologic time - most recent first - numbers are millions of years ago and mark the end of the timeframe

Contents

Phanerozoic eon

Cenozoic era

Neogene period

Holocene epoch
Pleistocene epoch
  • 0.011 - rise and fall of the large mammals, evolution of man
Pliocene epoch
  • 1.8 - ice age, modern mammals and molluscs appear
Miocene epoch

Paleogene period

Oligocene epoch
  • 23 - warm climate, rapid evolution,
Eocene epoch
  • 34 - archaic mammals, start of current ice age
Paleocene epoch
  • 56 - tropical climate, first large mammals

Mesozoic era

Cretaceous period

Upper epoch
  • 65 - flowering plants, fish, dinosaurs
Lower epoch
  • 100 - break up of Gondwanaland

Jurassic period

Upper epoch
  • 145 - ferns
Middle epoch
  • 161 - lizards
Lower epoch
  • 175 - ammonites

Triassic period

Upper epoch
  • 200 -- archosaurs
Middle epoch
  • 230 - amphibians
Lower epoch
  • 245 - first small mammals

Paleozoic era

Permian period

Lopingian epoch
  • 251 - supercontinent of Pangea
Guadalupian epoch
Cisuralian epoch

Carboniferous period

Upper Pennsylvanian epoch
  • 299 - winged insects
Middle Pennsylvanian epoch
  • 306 - reptiles, coal forests
Lower Pennsylvanian epoch
  • 312 - high oxygen content atmosphere
Upper Mississippian epoch
  • 318 - primitive trees
Middle Mississippian epoch
  • 326 - priomitive sharks
Lower Mississippian epoch
  • 345 - glaciation

Devonian period

Upper epoch
  • 359 - clubmosses
Middle epoch
  • 385 - crinoids
Lower epoch
  • 398 - jawed fish

Silurian period

Pridoli epoch
  • 416 - first vascular land plants
Ludlow epoch
  • 419 - millipedes
Wenlock epoch
  • 423 - corals
Llandovery epoch
  • 428 - trilobites

Ordovician period

Upper epoch
  • 443 - invertebrates dominant
Middle epoch
  • 461 - starfish
Lower epoch
  • 471 - first land plants

Cambrian period

Furongian epoch
  • 488 - Cambrian explosion of life
Middle epoch
  • 501 - Trilobites
Lower epoch
  • 513 - sponges

Proterozoic eon

Neoproterozoic era

Ediacaran period

  • 542 - first multi-celled animals

Cryogenian period

  • 630 - snowball earth

Tonian period

  • 850 - acritarch radiation

Mesoproterozoic era

Stennian period

  • 1000 - formation of Rodinia

Ectasian period

  • 1200

Calymmian period

  • 1400

Paleoproterozoic era

Statherian period

  • 1600 - first complex single-celled life

Orosirian period

  • 1800 - transition to oxygen atmosphere

Rhyacian period

  • 2050

Siderian period

  • 2300

Archaean eon

Neoarchean era

  • 2,500 - stabilization of most modern cratons

Mesoarchean era

Paleoarchean era

Eoarchean era

  • 3,600 - first single-celled organisms

Hadean eon

  • 3,800 to 4,100 - oldest known rock
  • 4,400 - oldest known mineral
  • 4,570 - Earth formed