A few days ago I was at Trichy, a city about 350 km from Bangalore. One of the places I visited was the Rock Temple. The Ganesha temple stands on a rock that is 3.6 billion years old! This is considered one of the oldest exposed rocks in the world and belongs to Earth’s infancy, the Hadean eon. It’s only a few million years younger than the world’s oldest exposed rocks that are in Australia and Canada apparently, and a lot older than the sedimentary rocks of the Grand Canyon.
As I stood outside the temple at the top I felt the ancientness of India in my soul. Looking down at the town spread out below me I was overcome by the sense of transience that assails me now and then. The spot where Trichy lies has been inhabited for hundreds of years; there are references to its existence in records from 2nd century BCE. A lot is known about Trichy from the 5th century CE, when it was ruled by a string of kings from different dynasties. But two thousand years is actually not a very long time.
When you come down to it, India is just a 100 km thick layer of crust-and-mantle floating on the Earth’s surface. It’s called the Indian plate and is half the thickness of the more robust China plate. Underneath it is viscous gunk that can liquefy anytime and send the Indian plate sliding under China! Geologists say our little chip rifted from Africa about 55 million years ago and was rapidly scooted northwards by mantle plumes deep under the ocean till it rammed into China, partially slid under China, and created the Himalayas.
The Indian tectonic plate doesn’t have deep lithospheric roots unlike the China plate. I imagine India spinning its wheels trying to find purchase, pressed against China by subterranean forces. On the surface of the earth India and China squabble over tiny bits of Arunachal Pradesh and Jammu & Kashmir. They are forced to diplomatically make the relationship work like two fifth-graders punished with detention for fighting over a desk to sit at. One day the whole of India could suddenly slide, i.e. subduct, under China and cease to exist! This is probably the wrong lens through which I should view international relations, but when I hear the things people running the world say, I wonder if the economics of oil and weapon sales is the only lens that is approved.
Knowing that I live on this fragile little piece of the earth’s crust gives me a sense of impermanence regarding our continents with their tidily drawn lines that separate countries into independent entities, each with its own government, people and culture. We confidently declare there are 195 countries. We live like it was this way since the beginning of time. And we make nukes to ‘protect’ ourselves from our bogeymen countries, when the odds are already stacked against our little Lilliputian race of Homo sapiens.
It took four eons to reach where we have. One eon is about a billion years. Should any of us even consider damaging the one and only beautiful, fragile blue-and-green marble we call home? Imagine if we could think of ourselves as Gondwanites, Laurentians or, even better, Pangaeans with no borders, or even merely earthlings!
5 thoughts on “thin crust”
Thank you so much for writing this Dr Shyamala. It propels us towards Truth. Thank you!
Nice read and analysis of the Indian plate.
Thank you for explaining that about India. Marion
Wonderful read . So interesting Dr. Vatsa .
That was very informative written with a lot of finesse! Enjoyed reading it Shyamala! Keep writing.