the Tethys Sea in three different phases following one after the other. Therefore, the Himalayas are supposed to have emerged out of the Himalayan Geosyncline, i.e.The Himalayas do not comprise a single range but a series of at least three ranges running more or less parallel to one another.The curved shape of the Himalayas convex to the south is attributed to the maximum push offered at two ends of the Indian Peninsula during its northward drift.The Indo-Gangetic plain was formed due to the consolidation of alluvium brought down by the rivers flowing from the Himalayas.Tibetan plateau was formed due to upthrusting of the southern block of the Eurasian Plate.And the folded sediments, after a lot of erosional activity, appear as the present-day Himalayas.This process is still continuing (India is moving northwards at the rate of about five cm per year and crashing into rest of Asia). Once the Indian plate started plunging below the Eurasian plate, these sediments were further folded and raised. ![]() An often-cited fact used to illustrate this process is that the summit of Mount Everest is made of marine limestone from this ancient ocean.This resulted in the folding of sediments. These sediments were subjected to powerful compression due to the northward movement of the Indian Plate.Sediments were brought by these rivers and were deposited on the floor of the Tethys Sea.We will study this in Antecedent and Subsequent Drainage). There were many rivers which were flowing into the Tethys Sea ( some of the Himalayan rivers were older than the Himalayas themselves.In between Laurasia and Gondwanaland, there was a long, narrow and shallow sea known as the Tethys Sea (all this was explained earlier in Continental Drift Theory).The southern part of Pangaea consisted of present-day South America, Africa, South India, Australia and Antarctica.Its northern part consisted of the present-day North America and Eurasia (Europe and Asia) which is called as Laurasia or Angaraland or Laurentia.During Permian Period (250) million years ago, there was a supercontinent known as Pangaea.Himalayan mountains have come out of a great geosyncline called the Tethys Sea and that the uplift has taken place in different phases.The Himalayas are the youngest mountain chain in the world.Formation of the Himalayans and the Tibetan Plateau due to Continent-Continent Convergence Thus, the fragments of oceanic crust are plastered against the plates causing welding of two plates known as suture zone. Suture zone: The subduction of the continental crust is not possible beyond 40 km because of the normal buoyancy of the continental crust. Examples: The Himalayas, Alps, Urals, Appalachians and the Atlas Mountains.As two massive continents weld, a single large continental mass joined by a mountain range is produced.The mountain belt erodes, and this is followed by isostatic adjustment. With the building up of resistance, convergence comes to an end.Huge slivers of rock, many kilometres wide are thrust on top of one another, forming a towering mountain range.As the continental plates converge, the ocean basic or a sedimentary basin (geoclinal or geosynclinal sediments found along the continental margins) is squeezed between the two converging plates. ![]() ![]() The two plates converge, buckle up ( suture zone), fold, and fault.
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