A man cries as he walks on the street while passing through a damaged statue of Lord Buddha a day after an earthquake in Bhaktapur, Nepal. Rescuers dug with their bare hands and bodies piled up in Nepal on Sunday after the earthquake devastated the heavily crowded Kathmandu valley, killing at least 1,900, and triggered a deadly avalanche on Mount Everest. Reuters A man cries as he walks on the street while passing through a damaged statue of Lord Buddha a day after an earthquake in Bhaktapur, Nepal. Rescuers dug with their bare hands and bodies piled up in Nepal on Sunday after the earthquake devastated the heavily crowded Kathmandu valley, killing at least 1,900, and triggered a deadly avalanche on Mount Everest. Reuters

A part of India slid about one foot to 10 feet northwards and underneath Nepal in a matter of seconds during the devastating 7.9-magnitude earthquake that hit the neighbouring country on Saturday, a US scientist has said.

"Saturday's slip took place over an area about 1,000 to 2,000 square miles over a zone spanning the cities of Kathmandu and Pokhara in one direction, and almost the entire Himalaya mountain width in the other," said Colin Stark, Lamont Associate Research Professor at the Lamont-Doherty Earth Observatory, Columbia University.



"A part of India slid about one to 10 feet northwards and underneath Nepal in a matter of seconds," Stark said.

"The rock (we call it the "crust", or more precisely 'lithosphere') below Bihar slid under Nepal along a zone from Bharatpur, through Hetauda, to Janakpur," Stark said. Read: Want to help Nepal earthquake survivors? Here is how you can do your bit

Sixty-nine members of the Fairfax County Virginia Urban Search and Rescue Team await takeoff on a U.S. Air Force C-17 Globemaster III aircraft at Dover Air Force Base, Delaware. Reuters Sixty-nine members of the Fairfax County Virginia Urban Search and Rescue Team await takeoff on a U.S. Air Force C-17 Globemaster III aircraft at Dover Air Force Base, Delaware. Reuters

"It's important to realise that all of northern India is sliding north under Nepal etc, all the time. The point is that the sliding takes place abruptly at different patches at different times," Stark said.

Geophysicists have long monitored how fast the Earth's plates are moving, and it is known that the entire subcontinent of India is being driven slowly but surely underneath Nepal and Tibet at a speed of around 1.8 inches per year, Stark earlier wrote in an article published on CNN website.

Over millions of years, the squeezing has crushed the Himalayas like a concertina, raising mountains to heights of several miles and triggering earthquakes on a regular basis from Pakistan to Burma. "Saturday's quake was neither unusual nor unexpected, although it was larger than most," Stark said.

A Nepal Army personnel carries an injured woman to an Indian Airforce helicopter following Saturday's earthquake in Sindhupalchowk, Nepal A Nepal Army personnel carries an injured woman to an Indian Airforce helicopter following Saturday's earthquake in Sindhupalchowk, Nepal

In the 81 years since the 1934 Bihar earthquake, which killed around 10,000 people, the land mass of India has been pushed about 12 feet into Nepal. "Think of all that movement getting stored in a giant spring lying under Nepal. The spring is stuck on a broad, rough surface which we call a fault plane," Stark said.

Sometimes, energy stored in the spring gets big enough to slip catastrophically, releasing all that pent-up strain and generating shaking strong enough to destroy buildings and kill people over a huge area, he explained.

The bigger the area that slips, and the larger the pent-up energy, the greater the damage. The death toll in Nepal's devastating earthquake today crossed 4,350, with more than 8,000 people injured.