11-11-2016, 10:37 AM
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The height of a swathe of the Himalayas has dropped by around one metre as a result of the devastating Nepal earthquake, scientists say.
But they add that the drop will roughly be balanced by slow uplift due to tectonic activity.
And they have yet to analyse satellite images of the region in which the most famous Himalayan peak - Everest - is located.
Geologically, It is postulated that due to the northeasterly movement of the Indian plate, the sedimentary layers of an ancient geocyncline called the Tethys (in between Indian and Eurasian Plates) were pushed upward to form the Himalayas.
It is estimated that the height of the Himalayas is increasing by 4 cm each year.
Geomorphic studies also conclude that the Brahmaputra is a paleo-river, older than the Himalayas, which often crosses higher altitudes in the Himalayas eroding at a greater pace than the increase in the height of the mountain range to sustain its flow. The height of the surrounding regions still increasing forming steep gorges in Arunachal.
But don't worry, it will decrease after a while:
Scientists believe that 65 million years ago, the Indian Plate moving north collided with the Eurasian Plate, and the upheaval saw the emergence of the Qinghai-Tibet Plateau as well as the Himalayas.
"Friction between the tectonic plates continues to this day, gradually pushing the Himalayas upward,"
"But at the same time, a horizontal pulling power inside the lower continental crust and mantle of the earth counteracts this upward movement," said Bian.
According to measurements made by scientists in 2005, the altitude of Mount Qomolangma, or Everest, is 8844.43 meters, 3.70 meters lower than the figure obtained in 1975.
The result suggests that the Himalayas and the Qinghai-Tibet Plateau will not continue to move up indefinitely. After growing to a certain height, the effect of gravity and collision-generated extrusion will make them grow horizontally, wider but not higher,
India as island
India was once a continent. More than 100 million years ago, when dinosaurs roamed the earth, most of what is now India was an island.
It had broken off from an ancient supercontinent referred to as Gondwanaland by paleogeographers (named after Gondwana, a forested area of central India), and was moving slowly northwards.
About 50 million years ago, dinosaurs by now extinct, the India continental plate collided with Asia, buckling the coastal area of both continents and creating the Himalayas - the world's youngest major mountain range - and, of course, the highest.
Evidence of this ancient history is provided by fossilised sea shells that can still be found high in the mountains. The plate on which the subcontinent rests continues to press slowly northwards, and is the reason why the height of Mount Everest increases slightly every year.