The amount of exposed land in the Hadean is only loosely dependent on the amount of continental crust: it also depends on the ocean level. In models where plate tectonics started in the Archean, Earth has a global ocean in the Hadean. The high heat of the mantle may have made it difficult to support high elevations in the Hadean. If continents did form in the Hadean, their growth competed with outgassing of water from the mantle. Continents may have appeared in the mid-Hadean, and then disappeared under a thick ocean by the end of the Hadean. The limited amount of land has implications for the origin of life.
