A History of Agriculture in India v1.c7.18

v1.c7.18

It is now generally believed that the uplift of the Himalayan system of mountain ranges was due to movements of two solid continental masses on two sides of the Tethys, directed towards one another. The Central Asian continental mass, Angaraland, slowly moved from the north to the south under pressure from the floor of the Arctic Ocean, and the northern edge of the Indian continental mass, the Gondwanaland, became downwarped by the northward compressive force from the Indian Ocean. The Himalayan portion of the Tethys gradually shifted southward and became narrower, assuming its present trend in the early Eocene time. The presence of tongue-like projections of the Gondwanaland—one in the Kashmir-Hazara region (the Punjab wedge) and the other in the north-eastern extremity of Assam (the Assam wedge)—have moulded the pattern of the Himalayan chain. The effects of these two wedges can be clearly seen in any relief map of India. It will be seen that the Himalayan chain occurs as a huge arc between Nanga Parbat in the west and Namcha Barwa in the east. The convexity of the arc points south towards the Indian peninsula. Though geographically the Himalayas are considered to be limited between these two points, the Nanga Parbat and the Namcha Barwa, the rock formations seem to be suddenly folded round at these points and to turn southward in rather parallel ranges.