• Entry
  • Reader's guide
  • Entries A-Z
  • Subject index

A geological time scale from the Geological Association of America showing the Cenozoic, Mesozoic, Paleozoic, and Precambrian eras of the Phanerozoic eon. Age estimates and picks of boundaries are rounded to the nearest whole number (1 Ma) for the pre-Cenomanian, and ...

    • Loading...
    locked icon

    Sign in to access this content

    Get a 30 day FREE TRIAL

    • Watch videos from a variety of sources bringing classroom topics to life
    • Read modern, diverse business cases
    • Explore hundreds of books and reference titles