Laurentia
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Laurentia is the craton at the heart of North America. Many times in its past, Laurentia has been a separate continent as it is now in the form of North America. During other times in its past, Laurentia has been part of a supercontinent. It is named after the Laurentian Shield.
This is an outline of the history of Laurentia over about three billion years:
Partial (incomplete) history of Laurentia in chronological order
- ~2.5 billion years ago, Arctica formed as an independent continent.
- ~2.45 billion years ago, Arctica was part of the major supercontinent Kenorland.
- ~2.1 billion years ago, when Kenorland shattered, the Arctican craton was part of the minor supercontinent Nena along with Baltica and Eastern Antarctica.
- ~1.8 billion years ago, Laurentia was part of the major supercontinent Columbia.
- ~1.5 billion years ago, Laurentia was an independent continent.
- ~1.1 billion years ago, Laurentia was part of the major supercontinent Rodinia.
- ~750 million years ago, Laurentia was part of the minor supercontinent Protolaurasia. Laurentia nearly rifted apart.
- ~600 million years ago, Laurentia was part of the major supercontinent Pannotia.
- ~Cambrian, Laurentia was an independent continent.
- ~Devonian, Laurentia collided against Baltica, forming the minor supercontinent Euramerica.
- ~Permian, all major continents collide against each other for forming the major supercontinent Pangaea.
- ~Jurassic, Pangaea rifted into two minor supercontinents: Laurasia and Gondwana. Laurentia was part of the minor supercontinent Laurasia.
- ~Cretaceous, Laurentia was an independent continent called North America.
- ~Neogene, Laurentia, in the form of North America, crashed into South America, forming the minor supercontinent America.
- ~250 million years from now, all continents will crash together for forming the major supercontinent Pangaea Ultima. Laurentia will be of Pangaea Ultima.
- ~400 million years from now, Pangaea Ultima will disintegrate, and no one knows what will happen to Laurentia when it does.
External links
- Paleogeography of the Southwestern US (http://jan.ucc.nau.edu/~rcb7/paleogeogwus.html) - Paleogeographic history of southwestern Laurentia, goes back to 1.7 billion years ago.
- Mesozoic Paleogeography and Tectonic History, Western North America (http://jan.ucc.nau.edu/~rcb7/mz_paleogeog_wus.html) - Paleogeographic history of western Laurentia, goes back to the Permian period.
Images
- Map of Laurentia (http://www.jamestown-ri.info/gondwana_500ma.gif) - A map of Laurentia
