1. It is believed that millions of years ago, India was the part of a big continent, known as the Gondwana land.
2. The Peninsular part of the Gondwana land was the oldest landmass. The Gondwana land included India, Australia, South Africa, South America and Antarctica as one single landmass.
3. The convectional currents split the crust into a number of pieces, thus leading to the drifting of the Indo-Australian plate after being separated from the Gondwana land, towards north.
4. The northward drift resulted in the collision of the plate with the much larger Eurasian plate.
5. Due to this collision, the sedimentary rocks which were accumulated in the geosyncline known as the Tethys were folded to form the mountain system of western Asia and Himalaya.
