Ordovician Timechart

The oldest period to be represented in the rocks of Fforest Fawr Geopark; it lasted from 485 to 444 million years ago.

The Ordovician Period

This period extended over 45 million years.  It is divided into three series/epochs, which are further subdivided into various stages/ages.

  • Late/upper Ordovician epoch (458Ma – 445Ma)
    • Hirnantian stage (445Ma – 444Ma)
    • Katian stage (453Ma – 445Ma)
    • Sandbian stage (458Ma – 453Ma)
  • Middle Ordovician¬†(Llanvirnian) epoch (470Ma – 458Ma)
    • Darriwilian stage (467Ma – 458Ma) (formerly Llandeilian)
    • Dapingian stage (470Ma – 467Ma) (formerly Abereiddian/Llanvirnian)
  • Early/lower Ordovician epoch (485Ma – 470Ma)
    • Floian stage (478Ma – 470Ma)
    • Tremadocian stage (485Ma – 478Ma)

Ma = million years (ago)