Scientists began to think that the continents were part of larger plates, based on information about the mid-ocean ridges and earthquakes.
Suess suggested the idea that the Earth's continents were originally two large continents, Laurasia an Gondwanaland.
Wegener suggested the idea of continental drift and the existence of an original supercontinent, Pangea.
Paleomagnetism in ocean rocks provided proof for seafloor spreading, convincing many scientists of the validity of the theory of plate tectonics.