Plate Tectonic Hypothesis
Tectonic plates are ‘rigid’ massive lithospheric blocks bounded by mid-ocean ridges, transform faults, suture zones and orogenic belts. The Earth can be divided into the Eurasian Plate, Pacific Plate, Indian Ocean Plate, African Plate, Americas Plate and Antarctic Plate, some of which are oceanic plates, and some of which are continental plates. The plate tectonics hypothesis proposes that mass drifting, cracking (mid-ocean ridges), subduction (circum-Pacific Benioff zone), collisions (continental suture zones) and long-distance movements of the six major plates and numerous secondary plates are the main mode of global lithospheric movements. The plate hypothesis holds that the rigid plates float on top of the upper mantle asthenosphere and that large-scale horizontal movements are caused by mantle convection. This hypothesis inherited the ideas of the ‘theory of continental drift’ and ‘mantle convection’ and has escalated them to a new theoretical level.