What is Laurentia?
Laurentia is another name for the North American craton, the large and very old chunk of rock that North America rests on. The “basement complex” (the metamorphic and igneous rock below the sedimentary layer) of Laurentia is 1.0 – 3.0 billion years old, and was created in a tectonically active setting, under great pressure and temperature. Its constituent rocks are all igneous oxides, like granite. Like the other continents, Laurentia gets pushed around by ocean spreading, bumping into them and occasionally forming supercontinents like Pangaea. Laurentia is named after the Laurentian craton, another name for the North American craton. The Laurentian craton is named after the St. Lawrence river, which flows over it. The Laurentian craton underlies the entire North American continent, but only reaches the surface in northern Canada, where the sedimentary rocks were scraped clean off during the last Ice Age. The Laurentian craton is the world’s largest exposed area of Archean (older than
