This may explain the enigmatic delay of the Andean orogeny, that is, the formation of the modern Andes.
2
Another mountain-building event, called the Alice Springs Orogeny, happened about 400 million years ago and played a role in Uluru's formation.
3
Some scientists believe the Appalachians experienced a fourth, earlier mountain-building episode, called the Grenville Orogeny, and that there may have been others earlier still.
4
The Appalachians were formed in three long phases (or orogenies, as geologists like to call them) known as the Taconic, Acadian, and Alleghenian.