Meghalayan Age or Age of Destruction!

Stalagmite sample from Mawmluh Cave

We are now officially living in the Meghalayan age, and this could also possibly be the “age of destruction” and an example is the Mawmluh Cave, which provided clues for this age, but is now under threat of being destroyed.

Select people are aware around the world that the bedrock for determining the age was laid by Prof. Ashish Sinha from the University of California, US in 2003.

When Prof. Sinha visited Meghalaya he took Stalagmite samples from Mawmluh cave near Sohra (Cherrapunjee) to the US for further studies as part of his research on the Indian Monsoon.

The samples provided the best chemical signatures how 4200 years back the Earth suddenly dried up owing to scant or no rainfall. The study was then carried forward by Prof. Sinha and other collaborating scientists and the results were published in 2012.

 

Mawmluh Cave entrance

Subsequently the International Commission on Stratigraphy named the age as “Meghalayan” after the place where the samples were taken from.

But here is the other part of the story. The Mawmluh Cave which provided vital signatures is under the Mawmluh Cheera Cements Limited and continued mining is destroying the Cave system. Not just Mawmluh, a large number of Caves in Meghalaya are under threat from illegal mining.

Inside Mawmluh Cave

Speaking over the phone from California, Prof. Sinha said, he has seen the  mining that's being carried out and destroying the Cave systems and the ecosystem therein.

“Countries around the world preserve Caves. Some Cave systems in different parts of the world are protected just like National Parks, Archeological sites and historical monuments. Caves are a storehouse of scientific data and a diverse ecosystem,” the scientist said.

He said that some of the different species that are being discovered in the caves could  possibly provide cure for diseases and advance research works. There are more reasons why the policy makers should protect these Caves and the environment.

Prof. Sinha says that across the globe it was found that rainfall pattern has become erratic due to “super-fast” climate change. “Of course there were climate changes through different ages in the present epoch (Greenlandian 11700 years that ended the ice age. Northgrippian, 8300 years ago, chilled the earth again.) But the rate at which climate change is taking place, mainly due to human interfernces now, is a matter of deep concern,” Prof. Sinha said.

Prof. Ashish SInha

In the previous ages, the climate changes were natural, but in Meghalayan age unprecedented human interventions and exploitation of Nature and its resources has accelerated climate change and destruction of the environment like the Mawmluh Cave.

Meanwhile, Prof. Sinha explained how the Stalagmites determined the present age. He said, rainwater dissolves Uranium in rocks and over time these are locked inside Stalagmites.

As Uranium decays, carbon dating Stalagmite samples makes it possible to date them. Then, Oxygen from rainwater found embedded in these stalagmites are analyzed. 

Two Oxygen Isotopes the lighter ¹⁶O and the heavier ¹⁸O are taken into consideration. The ratio of their distribution in the Stalagmites depends on the rainfall over the surface of the caves and therefore the amount of rainfall in a specific age is corelated.

Caves are the best places to get such samples as they remain hidden from the elements and therefore provide pristine samples. “The dating of the Mawmluh Stalagmites and determining the rainfall over the Caves over a period of 4200 years was similarly done,” Prof. Sinha said.

The Paleo-climatologist said the Mawmluh Cave which has helped embed Meghalaya’s name deep into Earth’s history for Epoch’s to come, needs more respect and must be ensured they aren't destroyed. (Eom)