When and how was the Himalayas formed

The journey of the Indian plate

  Tectonic model for the extrusion of the 'Greater Himalayan Sequence'

Consequences of a plate collision

Together with the highlands of Tibet, the Himalayan Mountains cover the largest mountain mass on earth with an area of ‚Äč‚Äčover one million square kilometers. The dramatic and very varied topography emerged in the last 50 million years after the continental Indian plate collided with the continental Eurasian plate. Before this time, the Indian plate drifted against the Eurasian continent, but with an oceanic lithosphere that was continuously subducted. The ocean "swallowed" was called Tethys and was ultimately only the eastern continuation of the ocean of the same name, which had existed between Africa and Eurasia before the formation of the Alps. It was only when the continental part of the Indian plate collided with the Eurasian plate that the two continental masses began to wedge one another, to push each other up or down: While part of India was being pushed under Tibet, the upper part was backwards onto the Indian plate pushed up, that is, placed on itself. These movements were made possible by the formation of several large-scale thrust surfaces. This piling up of continental crust packages formed the Himalayas. Before the continental collision with Eurasia, the Indian plate had a speed of about 15 to 20 cm / year, after the collision this was reduced to 5 cm / year. At this speed, India has persistently advanced 2,000 km into the Eurasian continent over the last 40 million years, which has led to a doubling of the crust thickness, the uplift of the Himalayas and the formation of the Tibetan plateau. Today's uplift rates are between 5 and 8 mm / year. In the Himalayas, however, there are also places with an uplift of 1 cm / year, which corresponds to 10 km in a million years. These uplift speeds are around five times higher than those in the Alps. With these remarkable growth rates it is astonishing that the mountains in the Himalayas are "only" 8 to 9 km high. The questions therefore arise: Why is the Himalaya not higher, where is the "missing" material located today? How high can mountains get, and what forces prevent them from infinite growth?