Model Question and Answers for APSC | Write a short note on Plate tectonics.
Ans : A tectonic plate (also called lithospheric plate) is a massive, irregularlyshaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plates move horizontally over the asthenosphere as rigid units. The lithosphere includes the crust and top mantle with its thickness range varying between 5 and100 km in oceanic parts and about 200 km in the continental areas. A plate may be referred to as the continental plate or oceanic plate depending on which of the two occupy a larger portion of the plate. The Pacific plate is largely an oceanic plate whereas the Eurasian plate may be called a continental plate.
The theory of plate tectonics proposes that the earth’s lithosphere is divided into seven major and some minor plates. Young Fold Mountain ridges, trenches, and/or faults surround these major plates.