Distribution of Oceans and Continents

Continental Drift Theory

Proposed by Alfred Wegener in 1912, this theory states that all continents were once joined together in a single supercontinent called Pangea, surrounded by a mega-ocean called Panthalassa, before breaking apart and drifting to their present positions.

Pangaea and Panthalassa

Pangaea was the massive supercontinent that contained all the Earth's landmasses, while Panthalassa was the vast universal ocean that encircled Pangaea during the Carboniferous period.

Convectional Current Theory

Suggested by Arthur Holmes, this theory explains that thermal convection currents operating in the Earth's mantle are the driving force behind the movement of crustal plates.

Sea Floor Spreading

Proposed by Harry Hess, this concept states that new oceanic crust is continually formed along mid-ocean ridges through volcanic activity and then moves outward laterally, proven by paleomagnetic studies.

Plate Tectonics

A comprehensive modern theory stating that the Earth's lithosphere is broken into major and minor rigid plates that float on the semi-fluid asthenosphere, interacting at convergent, divergent, and transform boundaries.