Proto-Laurasia

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Proto-Laurasia ("first Laurasia") was an ancient supercontinent. It has been part of two major supercontinents - Rodinia, and Pannotia. In Rodinia, South China, Baltica, and Siberia were connected to Laurentia (North America) on the eastern side of the craton. Laurentia (future North America) was rotated clockwise from today. Its western side (today's western North America) was facing north, the future Arctic shore was facing the east. Proto-Laurasia had neighboring, connected continents - Amazonia to the south, West Africa to the southwest, Congo to the west, and Antarctica/Australia to the north. Rodinia broke up into Proto-Laurasia and Proto-Gondwana. One of the rifts gave rise to the Panthalassic Ocean to the north. Proto-Laurasia broke (temporarily) into four independent continents -- South China, Baltica, Siberia, and Laurentia.

The continental fragments (Baltica, Siberia, and Laurentia, but not South China) assembled back together to form the next supercontinent, Pannotia. Pannotia was shaped like a "V", facing northeast Map of Pannotia. The southeast portion of the supercontinent was Proto-Laurasia, which was positioned near the South Pole and as shown in the map was covered with glaciers (along with Amazonia and West Africa). When Pannotia rifted in the Late Proterozoic Eon, Pannotia rotated in a westward direction. Proto-Laurasia rifted away from Proto-Gondwana and slowly drifted across the Panthalassic Ocean. The rifting spawned a new ocean between the continents, the Proto-Tethys Ocean. Just before the beginning of the Paleozoic Era (545 million years ago), Proto-Laurasia itself rifted again into three continents - Laurentia, Baltica, and Siberia. The rifting also spawned two new oceans between them - the Iapetus Ocean, which was situated between Laurentia and Baltica, and the Khanty Ocean - which was situated between Baltica, and Siberia. These two oceans expanded in the Cambrian Period. Millions of years later, these three continents would come back together again, creating Laurasia, for the assembly of the most recent continent of Pangaea. And again, Laurasia broke into North America (formerly Laurentia ) and Eurasia (Baltica and Siberia connected, with additional cratons).