Being one of the Earth’s original continents, it started forming about 3 billion years ago; when the Earth was comparatively hotter and the mantle convection too was vigorous. Gradually, the Earth cooled and the floating pieces of lithosphere, known as cratons, stopped growing. Since then the plates have been moving back and forth across the globe, eventually colliding to form the continents. In the early Cambrian period, about 500 million years ago, the cratons of Siberia and Laurentia broke off to form the main landmass of Pangaea; which was later known as Gondwana. Eventually by the Mesozoic Era, the Laurentian and Eurasian cratons combined to form the supercontinents of Laurasia. This separation of Eurasian and North American Plates led to the separation of North America from Asia.
The North American Plate is roughly 75,900,000 sq. km, with an estimated relative velocity of about 0.68cm. The North American Plate moves about 2.5cm towards the south-west each year.
It is believed that a few hotspots exist below the North American Plate. A few notable hotspots are the Raton (New Mexico), Yellowstone (Wyoming) and Anahim (British Columbia) hotspots. It is thought that these were caused by a narrow stream of hot mantle convecting up the Earth’s core known as a mantle plume. Some experts also believe upper-mantle convection to be the cause. The Anahim and Yellowstone hotspots are believed to have arrived during the Miocene period and are geologically still active, causing volcanoes and earthquakes.
Due to the collision of the North American Plate and the African Plate as well as due to the wrinkling of the Earth’ surface, the Appalachian mountains were formed. An important fact which makes it important is that around six micro-continents collided and got stuck together to build the North American craton. This eventually became a part of the three super continents, namely Pangaea, Laurasia and Laurussia.