Earth's interior 60 degrees hotter than thought, says study

New Delhi: A recent survey says that the Earth's mantle is about 60 degrees Celsius hotter than previously thought, a new study has found.

The findings led by Woods Hole Oceanographic Institution (WHOI) in the US could change how scientists think about many issues in Earth science including how ocean basins form.

A 60-degree increase may not sound like a lot compared to a molten mantle temperature of more than 1,400 degrees Celsius, researchers said.

However, the result is significant as a hotter mantle would be more fluid, helping to explain the movement of rigid tectonic plates, they said.

Since it is not possible to measure the mantle's temperature directly, geologists have to estimate it through laboratory experiments that simulate the high pressures and temperatures inside the Earth.

Water is a critical component of the equation: the more water (or hydrogen) in rock, the lower the temperature at which it will melt.

The peridotite rock that makes up the upper mantle is known to contain a small amount of water.

To figure out how the water content of mantle rock affects its melting point, Emily Sarafian, a graduate student in the MIT-WHOI Joint Programme conducted a series of lab experiments.

She used a piston-cylinder apparatus, a machine that uses electrical current, heavy metal plates, and stacks of pistons in order to magnify force to recreate the high temperatures and pressures found deep inside the Earth.

(With PTI inputs)