The incredible energy unleashed by the magnitude-7.8 earthquake that hit Nepal on April 25 moved Mount Everest more than an inch.
The world's tallest mountain shifted 1.18 inches (3 centimeters) to the southwest during the quake, according to the state-run China Daily newspaper, which cited a new report by China's National Administration of Surveying, Mapping and Geoinformation
It's impossible, however, to predict when such a quake might occur, or whether April's quake influenced the chances of a later temblor.
"Movement on this fault will have affected nearby faults, and some of the faults will be promoted closer to failure [causing a quake], and some will be pulled farther away from failure," Briggs said. "The trouble we have is the timing part. We don't know where all these faults are in their kind of 'clocks' and how close they were to kind of going anyway."
Complicating the guessing game is the lack of geological evidence. The type of quake that shook Nepal doesn't necessarily leave a strong trace in the rock record, Briggs said.
Imagine a hand pushing on a metal ruler until the instrument bows. When the ruler finally springs back against the pressure, as the Eurasian plate did against the pressure of the Indian plate, it changes shape. But the overarching pressure of the hand (or Indian plate, in this case) continues, deforming the ruler back into its bowed shape.
"Kathmandu is going to go down, and it's going to move back in the direction of Asia, and the Himalaya [region] is going to come back up," Briggs said. The changes in the Earth are elastic, he said, and "they're mostly canceled out in between the big earthquakes."
The quake was also what is known as a "blind rupture," meaning there was no visible fault line or cracking at the surface. That makes it harder to see how many times such a quake has happened before, and how likely it is to happen again.
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