An earthquake of magnitude 8.5 or more in one of the overlapping segments of the central Himalayas is expected anytime in the future, according to a new study led by seismologist CP Rajendran of the Jawaharlal Nehru Centre for Advanced Scientific Research in Bengaluru. The study, published in "Geological Journal", said the fact after this massive earthquake, the frontal thrust in the central Himalayas (covering parts of India and eastern Nepal) has remained seismically quiet for 600 to 700 years, implying enormous build-up of strain in the region, reported news agency IANS.
Before the new research, the scientists carefully studied the existing database. The new study explored locales -- Mohana Khola in far western Nepal and Chorgalia, which falls within the Indian border, to determine the timing of the last faulting event on the frontal thrust of the central Himalayas.
For the research, the scientists studied the local geology and structural map published by the Geological Survey of India and used Google Earth and imagery from Indian space agency ISRO's Cartosat-1 satellite.
The analysis, the researchers say, "compels us to conclude that a great earthquake of magnitude 8.5 or more that occurred between 1315 and 1440 had unzipped a stretch of about 600 km (the length of central seismic gap from Bhatpur to beyond Mohana Khola) in the central Himalayas with an average slip (or displacement) of 15 metres".
"An earthquake of magnitude 8.5 or more is overdue in this part of the Himalayas, given the long-elapsed time.
"Considering this potentially high seismic risk, this will be particularly catastrophic for a region marked by an ever-growing population and unhindered expansion of the built-up environment, to be contrasted with poor preparedness to meet this contingency," Rajendran told the news agency.
(With agency inputs)