2. Physical Features of India
Formation Of Relief/Physical Features Of India
India is made up of mountains, Plains, Plateaus, desert and islands etc. The action and reaction of many natural forces above and below the earth’s crust for millions of years went into the formation of the present physical features of India. Some such forces are the earthquakes, the volcanic eruptions, heat of the sun and above all the movement of the tectonic plates etc.
Earth scientists have attempted to explain the formation of physical features with the help of "Theory of Plate Tectonics". According to this theory, the crust (upper part) of the earth has been formed out of seven major and some minor plates.
Tectonic Plates :
Due to internal heat of the earth, the current of the semi-molten rocks begin to move towards the crust and tear it apart dividing it into large fragments, called lithosphere or tectonic plates. There are seven major plates namely, South America, North America, Pacific, Indo Australian, Eurasian, African and Antarctic.
Types of plates :
Tectonic plates are always in the process of moving in one direction or the other. These movements are generally classified into three types –
(A) Diverging Plates : If these plates move away from each other, they are called diverging plates. The boundary they form is called divergent boundary.
(B) Converging Plates : If these plates are pushed together, they are called the converging plates. The boundary they make is called convergent boundary.
(C) Transform Plates : Converging plates sometime neither collide with each nor slide under the other but they move horizontally push each other. Such plates are called the transform plates and boundary they make is called the transform boundary.