Nepal earthquake was a tragedy waiting to happen
Study conducted by IISc had foreseen disaster in 2011-12
They had made this forecast based on probabilistic seismic hazard analysis (PSHA) study in 2011- 12. Now, they opine that more such quakes could occur in the days to come.
Prof T G Sitharam of Department of Civil Engineering, IISc and his student Dr Sreevalsa K, had conducted a study in 2011-12 titled “Probabilistic Seismic Hazard Analysis of India.”
The study had stated that earthquake can occur in parts of north India, North East India, North West India, Nepal, Himalayas and surrounding regions in near future which lie on the plate boundaries between Indian plate and Eurasian plate.
“People are complacent in and around Bihar and Kangra regions, spread across 200 km, as no earthquake had occurred in the last 100 years. So, the strains which had got accumulated got released rigorously when the seismic plates collided.
We had assessed a major earthquake in this region based on PSHA. The one which occurred on April 25, 2015 in Nepal was a reasonably small one, bigger one is due. Another was experienced on April 26, 2015. This could a precursor for more to occur in the forthcoming days. It could either be of the same intensity, lesser or even bigger,” Prof Sitharam told Deccan Herald on Sunday.
Scientific studies cannot predict the exact time as to when such a disaster would occur. But looking at the present scenario, if similar tremors and quakes continue for another couple of days, then aftershocks can continue even for a week or a month. People are thus advised to be prepared.
But if nothing happens for the next couple of days, then people can be relaxed as nothing more would occur, Prof Sitharam said.
He mentioned that as per Indian standards, and as explained in the study, India is divided into four zones. Most parts of North India, North East and North West and Bhuj area fall under Zone-5 which is most prone to earthquakes. Zone- 4 which covers Delhi and surrounding regions is less prone compared to Zone -5.
Zone- 3 covers Madhya Pradesh, Odisha, Bengal and surrounding areas; Zone-2 covers South India including Karnataka, Tamil Nadu and surrounding areas. There is no Zone-1 as no region is earthquake-resistant and it was removed from the Indian standard list also, Prof Sitharam explained.
Seismic hazard map
The team had also prepared a seismic hazard map which showed that the region between Himalayas, North East, Burma, Kashmir, and Bhuj are most vulnerable to earthquakes.
The one which occurred in Nepal is a shallow earthquake which generates a lot of energy and spreads far and damages near-surface structures drastically, he saidThe IISc professor added that earthquakes do not kill people. Seismic-resistant building design can reduce the loss of life and property.