IS EARTH HEADING TOWARDS BECOMING A 'WATER WORLD'?

Earth's continental crust, which forms the land we live on, is getting thinner and could disappear entirely in two billion years, turning our planet into a water world.

According to a new estimate, Earth's continental crust has been slimming down and if this slimming rate holds, the continents might disappear into the sea. 

As the continental crust erodes, land would disappear into the oceans, even without climate induced sea level rises. 

Collated measurements of 13000 rock samples from around the world to reconstruct the history of continental crust. 

The thickness of crust has been estimated different times in the past, inferring the rise and fall of continents over the Earth's history.

Continents today are about 35 Kilometers thick, on average, with the buoyant rock bobbing next to the 7-kilometer, denser oceanic crust, which rides lower.

Continental crust peaked in thickness about a billion years ago around the time Earth's mightiest continents banded together to form the supercontinent Rodinia

Researchers have said the mountains raised by that event have been eroding ever since, and hot enough new crust is forming to offset the losses.

If it continues for the next 2 billion years, then the crust will again reach that state where the continents are submerged beneath the ocean.