Is it ensure, insure, or assure?
A large continent that, according to the theory of plate tectonics, is thought to have split into smaller continents in the geologic past. The supercontinent Pangaea is believed to have formed when earlier continental landmasses came together sometime before the Permian Period, staying together until after the Triassic Period, when it broke into the smaller supercontinents Laurasia and Gondwanaland. These supercontinents are believed to have later separated into the landmasses that correspond to the current continents. Other supercontinents are hypothesized to have formed and broken apart earlier in geologic time.