According to the National Centre for Seismology (NCS), 29 Indian cities and towns fall under “severe” to “very severe” seismic zones. The Bureau of Indian Standards (BIS) has classified different regions in the country into zones II to V, taking into consideration earthquake records, tectonic activities and damage caused, the director of the NCS, Vineet Gauhlat, said.
Seismic microzonation is the process of subdividing a region into smaller areas having different potential for hazardous earthquake effects.
Zone II is considered the least seismically active, while Zone V is the most active covering the entire north-eastern region, parts of Jammu and Kashmir, Himachal Pradesh, Uttarkhand, the Rann of Kutch in Gujarat, parts of north Bihar and the Andaman and Nicobar archipelago. Zone IV and V fall under “severe” to “very severe” categories respectively. Parts of Jammu and Kashmir, Delhi, Sikkim, northern Uttar Pradesh, West Bengal, Gujarat and a small part of Maharashtra fall under Zone IV.
Bhuj, which was struck by a massive earthquake in 2001 in which 20,000 people were killed, Chandigarh, Ambala, Amritsar, Ludhiana and Roorkee fall under zones IV and V.
“The Himalayan arc, stretching from the upper Assam region to Jammu and Kashmir, is known to be a high seismic zone and these cities in the Indo-Gangetic belt fall within reasonable limits of the Himalayas. So repercussions are bound to be felt there,” said Kusala Rajendran, a professor at the Indian Institute of Science (IISc), Bengaluru.
Rajeevan, Secretary, Ministry of Earth Sciences, said 31 new earthquake observatories will come up in the country by March next year. At present, there are 84 observatories.
