Mount Everest: A river may be making world’s highest peak taller

Everest stands on the border between China and Nepal, and its northern part is on the Chinese side. The Arun river flows down from Tibet into Nepal and then merges with two other rivers to become the Kosi which then enters northern India to meet the Ganges.

It is a very high silt-yielding river given the steepness of the mountains it flows through and the force it has, allowing it to carve off so much rock and soil on its way.

But the UCL researchers say it most likely earned its real strength when it “captured” another river or water body in Tibet 89,000 years ago, which in geological timescales is a recent event.

A Chinese academic, Dr Xu Han of China University of Geosciences, was the lead author in the study during a scholarship visit at the UCL.

“The changing height of Mount Everest really highlights the dynamic nature of the Earth’s surface,” he said.

“The interaction between the erosion of the Arun river and the upward pressure of the Earth’s mantle gives Mount Everest a boost, pushing it up higher than it would otherwise be.”

The UCL study says the Arun river most likely gained the capacity to carve off an extraordinary amount of rocks and other materials after it captured another river or water system in Tibet.