Hyderabad: Seismic events in the Himalayan region and South India are mutually exclusive, a Hyderabad scientist claimed. Retired NGRI seismologist Dr B. Rama-lingeswara Rao put forth a hypothesis that the Himalayan region becomes seismically active every 44 years and when it is active, South Indian region becomes seismically inactive negating the possibility of earthquakes here.
Dr Rao is writing a book on Indian seismicity sponsored by the Department of Science and Technology. In his hypothesis, based on the analysis of earthquakes since 1800, Dr Rao claimed that earthquakes cannot occur in the North Indian Plate Boundary and the South Indian Shield at the same time. He claimed that seismic activity in the Indian plate follows a cycle of roughly 22 years. When seismically active, NIPB or the Himalayan region, till New Delhi, carries the possibility of catastrophic earthquakes with magnitudes above 7.7.
On the other hand, the SIS covering the South Indian region has the possibility of earthquakes of magnitude 6.0 when seismically active, Dr Rao explained. He claimed that the tragic Kashmir earthquake of 2005 was the first massive earthquake after the initiation of the current cycle when the Himalayan region became seismically active again. “From earthquake data between the year 1800 and now, it appears that there is a rough 22 year cycle that is followed when the two regions alternatively seismically switch on and off,” Dr Rao said.
