By Shakoor Rather :
THE entire Himalayan arc is threatened by a possible sequence of massive earthquakes, and the next big quake -- of the magnitude of 8 or above -- may occur during our lifetimes, according to a study reviewing geological, historical, and geophysical data.. The human toll of such an event in the densely populated countries across the arc is likely to be unprecedented, the researchers said. The study notes that the sequence of future Himalayan earthquakes could be similar to the great earthquakes that occurred in the twentieth century along the Aleutian subduction zone, which extends from the Gulf of Alaska to Kamchatka in Russian Far East.
The review, which appeared in the journal Seismological Research Letters in August, used basic geological principles --stratigraphic analysis, structural analysis, soils analysis, and radiocarbon analysis -- to estimate the size and timing of prehistoric earthquakes and evaluate future risk. “The entire Himalayan arc extending from the eastern boundary of Arunachal Pradesh (India) in the east to Pakistan (in the west) has in the past been the source of great earthquakes,” study author Steven G. Wesnousky told PTI.
“These earthquakes will occur again and scientifically, it would not be a surprise if the next great earthquake occurred in our lifetimes. But the resolution of our studies is at best on the order of 100 years, longer than a human lifetime,” said Wesnousky, a professor of geology and seismology and director of the Center for Neotectonic Studies at the University of Nevada at Reno, US. Seismologist Supriyo Mitra noted that the research matches previous studies. “The Himalayan faults, as shown in the paper, are poised to produce an 8-plus magnitude earthquake. So yes, we are staring at a big one in the future. How far from now no one can tell,” Mitra, who was not involved in the study, told PTI.