The earth is composed of several plates. In the past there was only one huge land mass or the Pangea. This Pangea broke up and drifted apart from one another. The Gondwana land was the southern part of this Pangea. Due to conventional current, this Gondwana land was further broken down and split into several parts. One part of this Gondwana, the Indo-Australian plate started drifting towards the North. As a result it collided with the Eurasian plate in the North. This collision caused the sedimentary deposition of the Tethys to get folded forming the Himalayas.
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