Gondwana Massif have been dated at 320–330 million years old, indicating that the subduction process initiated in the early Carboniferous.This was relatively short lived (lasting about 20 million years), and initial contact of the two landmasses occurred in the mid-Carboniferous, with broader collision during the early Permian. In the Devonian an island arc named Chaitenia accreted to Patagonia in what is now south-central Chile. Gondwana and Laurasia formed the Pangaea supercontinent during the Carboniferous. Pangaea began to break up in the Mid-Jurassic when the Central Atlantic opened. In the western end of Pangaea, the collision between Gondwana and Laurasia closed the
Geology of Saskatchewan and marine life. The Williston basin was formed creating a lowered land area during this period filling with the Winnipeg Sea. The Williston basin was mainly south of Saskatchewan but extended north into the Saskatchewan plains area. Laurasia was created near the end of the Silurian Period. Laurasia was formed from the joining of Laurentia with Gondwana and two smaller continents which had broken off Rodinia. The orogeny between Laurasia and Gondwana created the Appalachian Mountains, and an exodus of water from the Laurasian land surface. In the early Devonian Period 418-361 Ma, Laurasia separated from Gondwana, creating a depressions