Geologicaltime

Geological Timeline

  • Precambrian Period

    Precambrian Period
    Event 10 The presence of stromatolites indicates that shallow seas covered much of Earth during intervals in this period. Event 11 Nearly half of the valuable mineral deposits in the world occur in the rocks of this period.
  • Period: to

    J Williams P6

    Geological Timescale
  • Cambrian Period

    Cambrian Period
    Event 22 Shelled brachiopods. Event 23 Trilobites appear.
  • Ordovician Period

    Ordovician Period
    Event 30 Colonies of tiny invertebrates call graptolites florished and vertibrates appear, Fish did not have jaws or teeth and their bodies were covered with bony plates. Event 1 There is very little plant life during this period.
  • Silurian Period

    Silurian Period
    Event 33 Vascular land plants and animals, such as scorpions begin to evolve on land. Event 24 Eurypterids (sea scorpions), sea stars and coral become more common.
  • Devonian Period

    Devonian Period
    Event 37 Age of Fishes, fish that can breath out of the water and spend time on land form. Event 31 Huge plants begin to develop, early amphibians form.
  • Mississippian Period

    Mississippian Period
    Event 2 Swamps and forests cover the land.
  • Pennsylvanian Period

    Pennsylvanian Period
    Event 4 Giant cockroaches appear. Event 15 Coal deposits form.
  • Permian Period

    Permian Period
    Event 38 Environmental change causes mass extinction of sea invertibrates (trilobites & eurypterids) as the seas retreat. Event 8 Appalachian Mountains are created because of the collision of tectonic plates & savannahs form.
  • Triassic Period

    Triassic Period
    Event 16 Welcome to the world of the Dinosaur! Enter the squirrel sized dinosaur & the first forest dwelling mammals appear. Event 34 Ichthyosaurs are living in the ocean, new invertebrates call ammonite develop.
  • Jurassic Period

    Jurassic Period
    Event 13 Whoa those dinos are getting big & dominate the land - Lizard-hipped and bird-hipped appear - carnivores and herbivores have arrived. Event 21 Early reptiles resembling large lizards appear.
  • Cretaceous Period

    Cretaceous Period
    Event 5 First flowering plants appear - angiosperm. Event 35 Impact hypothesis - dinosaur mass extinction.
  • Paleocene Period

    Paleocene Period
    Event 12 First primates evolve. Event 29 Smalll rodents evolve.
  • Eocene Period

    Eocene Period
    Event 17 Flying squirrels, whales and bats appear. Event 25 World wide temperatures drop about 4 degrees celsius (39.2 degrees fahrenheit).
  • Oligocene Period

    Oligocene Period
    Event 6 Himalayas develop due to uplifting caused by the Indian subcontinent and Eurasian continents colliding. Event 27 Many early mammal become extinct, clams and snails flourish.
  • Miocene Period

    Miocene Period
    Event 32 Antarctic icecaps begin to form. Event 36 Mediterranean Sea dries up and refills several times due to tectonic forcesa dn dropping sea levels.
  • Pliocene Period

    Pliocene Period
    Event 18 Various species migrated between continents across land bridges. Event 26 First modern horses appear.
  • Pleistocene Period

    Pleistocene Period
    Event 20 Species that did not evolve to survive extreme cold moved to warmer climate areas or became extinct (dire wolf & giant ground sloth). Event 9 Homosapien (modern humans) appeared & are hunters.
  • Holocene Period

    Holocene Period
    Event 19 The last glacial period ended and sea levels rose, Great Lakes formed. Event 28 Modern human developed agriculture and used tools made of bronze and iron.
  • Anthropocene Period

    Anthropocene Period
    Event 7 Some scientists believe that human kind has caused mass extinctions of plant and animal species, polluted the oceans and altered the atmosphere. Event 14 There is argument as to when this epoch began, some scientist think it began with the industrial age in the early 1800's other think it began with the atomic age in the 1950's.