Washington, Nov 10: Using computer simulations, a research team from the University of Colorado has found that mega-earthquakes occur in the Himalayan region every 1,000 years or so to empty a reservoir of energy in southern Tibet.
Washington, Nov 10: Using computer simulations, a research team from the University of Colorado has found that mega-earthquakes occur in the Himalayan region every 1,000 years or so to empty a reservoir of energy in southern Tibet.
According to a paper published in today’s issue of the journal Nature, earthquakes in the past 200 years in the central Himalayan region, though catastrophic, have released modest amounts of the energy that in turn has led to India''s collision with the Tibetan plateau.
Colorado researchers Roger Bilham and Nicole Feldl have based their claims on GPS point motions across the Himalayas that indicate where strain energy is stored and how it was released over a period of time.
Bilham and Feldl have reported their conclusions in a paper titled "Great Himalayan Earthquakes and the Tibetan Plateau."
The National Science Foundation has funded the research.
In the past, experts have resorted to estimating the timing of future earthquakes from the slip that occurred in former ones. However, the new information should help scientists’ forecast future seismic activity in the region, Bilham said.
"We had always assumed that earthquakes in the region were driven by the release of energy accumulating near the Greater Himalaya. Our recent calculations suggest that a substantial volume of the southern Tibetan plateau plays a significant role in driving great ruptures. Exhumation of ancient archives and surface ruptures are now needed to show the details of this process in the past 2,000 years to help us forecast future earthquakes - and save lives," said Bilham.
The Greater Himalaya forms a 2,000-kilometer arc separating northern India from Tibet and boasts the world''s highest peaks, including Mount Everest, at more than 29,000 feet.
The region is highly prone to earthquakes and has produced some of the deadliest on earth.
"Our findings show that great earthquakes - those with a magnitude of 8.2 or greater - can re-rupture regions that already have ruptured in recent smaller earthquakes, or those with a magnitude of 7.8 or below," Bilham said.
Mega earthquakes, those with a magnitude of 8.4 or greater, apparently occur every 1,000 years and are driven by residual strain following centuries of smaller earthquakes, or those with a magnitude of 7.6 or lower, according to the report.
Bureau Report
