Indian subcontinent sits on a tectonic plate called “Indian Plate”. A tectonic plate is a part of uppermost crust of the Earth’s surface called “lithosphere”. Below this lithosphere is a semi-solid layer of “asthenosphere”. The semi-solid nature of asthenosphere makes tectonic plates of lithosphere float. The Indian Plate is pushing against African Plate and Arabian Plate in the west. It is relatively stable against Australian Plate in the east and south, but is constantly pushing towards Eurasian Plate in the north. The boundary line with Eurasian Plate is where Himalayan mountain ranges are. And, the reason those mountains are getting taller every year is this constant pushing match between the Indian Plate and the Eurasian Plate.
This floating movement between plates can range from anywhere between 50mm to 100mm per year. To naked eye this movement of up to 0.0002 mm per minute is impossible to notice, but over a long period, say in next 1000 years, Indian Plate will move by a meter from it’s current location. Instead of fast forward button, hit a rewind button and imagine where Indian subcontinent would have been 250 milion years ago. It was actually part of a supercontinent which we now call “Pangaea”. On this supercontinent, Africa, Antarctica and Australia were the immediate neighbors of Indian subcontinent; with ocean to it’s north-east. Yes, ocean to the north-east! There were no Himalayan mountain ranges…at least not yet. Himalayan mountain ranges started to form around 70 million years ago (making them one of the “youngest” ones), when Eurasia was pushed closer to the Indian Plate at ~15 cm per year rate, by the very action of separation between African and South American Plate. To this date, as a result of this drifting, Himalaya continues to grow taller at the rate of ~5 mm per year. It is quite amusing to think that since the days of Tenzing Norgay and Edmund Hillary (who scaled it for the 1st time in May 29, 1953), Mt. Everest could have already grown taller by almost a foot.
This floating movement between plates can range from anywhere between 50mm to 100mm per year. To naked eye this movement of up to 0.0002 mm per minute is impossible to notice, but over a long period, say in next 1000 years, Indian Plate will move by a meter from it’s current location. Instead of fast forward button, hit a rewind button and imagine where Indian subcontinent would have been 250 milion years ago. It was actually part of a supercontinent which we now call “Pangaea”. On this supercontinent, Africa, Antarctica and Australia were the immediate neighbors of Indian subcontinent; with ocean to it’s north-east. Yes, ocean to the north-east! There were no Himalayan mountain ranges…at least not yet. Himalayan mountain ranges started to form around 70 million years ago (making them one of the “youngest” ones), when Eurasia was pushed closer to the Indian Plate at ~15 cm per year rate, by the very action of separation between African and South American Plate. To this date, as a result of this drifting, Himalaya continues to grow taller at the rate of ~5 mm per year. It is quite amusing to think that since the days of Tenzing Norgay and Edmund Hillary (who scaled it for the 1st time in May 29, 1953), Mt. Everest could have already grown taller by almost a foot.
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