ORIGIN OF THE OCEANS
Early Earth lacked an atmosphere after the impact that formed the Moon and as a result cooled very quickly. Within 150 million years, a solid crust must have formed. The Earth’s interior was much hotter than it is today and steam escaping from the crust as well as other gases were released by volcanoes.
The large amount of water on Earth can never have been produced by volcanism and degassing alone. It is assumed the water was derived from impacting comets that contained ice.
THE FIRST CONTINENTS
Plate Tectonics is driven by mantle convection which causes heat to flow from the core to the Earth’s surface. Because the mantle was hotter back in Earth’s early history convection in the mantle would have been faster and plate plate tectonics would have gone faster too. Most geologists believe that during this time with subduction zones more common, tectonic plates would have been smaller.
The initial crust that formed when the Earth’s surface first solidified, totally disappeared from a combination of this fast Hadean plate tectonics and the intense impacts.
A WARMER TROPICAL EARTH
MODERN DAY CONTINENTS
Plate Techtonics contributed to the continents as we know them. Over the course of several million years the once supercontinent surrounded by one super ocean broke up and the fragments drifted in different directions.