UPSC 2014 CDS II GK Paper

Statement (d) is not correct because subduction zones areformed along the ‘convergent plate’ boundaries and not the divergentplate. In 1967, McKenzie and Parker suggested the theory of plate tectonics. The theory was later outlined by Morgan in 1968. According to the theory of plate tectonics, the earth’s lithosphere is broken into distinct plates which are floating on a ductile layer called asthenosphere (upper mantle). Plates move horizontally over theasthenosphere as rigid units.