Should the massive 7.5 magnitude earthquake be yet another wake up call for us?
This is the second big earthquake in 2015 to have struck in the vicinity of the country and the Himalayan Alpine belt. On April 15, a 7.9 magnitude quake devastated large parts of Nepal, causing a huge loss to humans, animals and the economy.
Said D Srinagesh, Head of Seismology Observatory at the Hyderabad-based National Geophysical Research Institute (NGRI): “We are in the most active phases of seismic action, with large earthquakes striking at shorter intervals. Therefore the urgent need to be vigilant and be prepared to meet the challenges”.
The Himalayan Alpine includes the Hindukush mountains, Afghanistan, Pakistan, China, India, Myanmar and Nepal. There is heightened seismic activity in the region which could pose serious threats, Srinagesh he told
Data records of seismic activity in the region show that after 1983, there have been two large earthquakes of 7 plus magnitude. One of them occurred at 20 km from the present one.
Less lethal The aftershocks will be fewer because the rupture in the earth is very deep, said Srinagesh. Also, they will be less lethal. In contrast, the Nepal earthquake was a shallow type with a depth of just 10 km. It triggered a series of aftershocks — a few dozen — some close to a magnitude of 6. These took a few weeks to taper off. Interestingly, while the magnitudes of these two earthquakes are quite similar, the damages caused by them are rather different.
While the respective depths are a significant reason, the population density close to the epicentre is another major factor.
Today’s earthquake is a sure reason to make constructions quake-resistant, said B Ramalingeswara Rao, seismologist and author of Seismic Activity - Indian Scenario .
“We must learn lessons from this earthquake, which is far away from Delhi. All the civil structures should have earthquake-resist designs based on Design Ground Motion identified by scientists,” he said .The recently developed seismic zoning map should be implemented.