what type of boundary is the himalayan mountains
Convergent boundary In plate tectonics, a convergent boundary, also known as a destructive plate boundary, is a region of active deformation where two or more tectonic plates or fragments of the lithosphere are near the end of their life cycle. This is in contrast to a constructive plate boundary (also known as a mid-ocean ridge or spreading center). As a result of pressure, friction, and plate material melting in the mantle, earthquakes and volcanoes are common near destructive boundaries, where subduction zones or an area of continental collision (depending on the nature of the plates involved) occurs. The subducting plate in a subduction zone is normally oceanic crust, and moves beneath the other plate, which can be made of either oceanic or continental crust. During collisions between two continental plates, large mountain ranges, such as the Himalayas are formed. In other regions, a divergent boundary or transform faults may be present.
Himalayas During the Upper Cretaceous, about 70 million years ago, the north-moving Indo-Australian plate (which has subsequently broken into the Indian Plate and the Australian plate[11]) was moving at about 15Â cm per year. About 50 million years ago this fast moving Indo-Australian plate had completely closed the Tethys Ocean, the existence of which has been determined by sedimentary rocks settled on the ocean floor and the volcanoes that fringed its edges. Since both plates were composed of low density continental crust, they were thrust faulted and folded into mountain ranges rather than subducting into the mantle along an oceanic trench.[10] 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.[12]