Continent a period of 2.0–1.8 billion years ago and broke up about 1.5–1.3 billion years ago. The supercontinent Rodinia is thought to have formed about 1 billion years ago and to have embodied most or all of Earth's continents, and broken up into eight continents around 600 million years ago. The eight continents later re-assembled into another supercontinent called Pangaea; Pangaea broke up into Laurasia (which became North America and Eurasia) and Gondwana (which became the remaining continents). The following table lists the seven continents with their highest and lowest points on land, sorted in decreasing highest points. † The lowest
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