[1] The major reason for the high frequency and intensity of the earthquakes is that the Indian plate is driving into Asia at a rate of approximately 47 mm/year.
[3][4] A World Bank and United Nations report shows estimates that around 200 million city dwellers in India will be exposed to storms and earthquakes by 2050.
The major activities currently being pursued by the National Center for Seismology include a) earthquake monitoring on a 24/7 basis, including real time seismic monitoring for early warning of tsunamis, b) operation and maintenance of national seismological network and local networks, c) seismological data centre and information services, d) seismic hazard and risk related studies, e) field studies for aftershock/swarm monitoring and site response studies and f) earthquake processes and modelling.
The specifications given in the design code (IS 1893: 2002) are not based on detailed assessment of maximum ground acceleration in each zone using a deterministic or probabilistic approach.
Jammu and Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Sikkim, parts of the Indo-Gangetic plains (North Punjab, Chandigarh, Western Uttar Pradesh, Terai, a major portion of Bihar, North Bengal, the Sundarbans) and the capital of the country Delhi fall in Zone 4.
Several megacities like Chennai, Mumbai, Pune, Kolkata, Bhubaneswar, Jamshedpur, Ahmedabad, Surat, Lucknow, Vadodara, Mangalore, Vijayawada, Coimbatore and the entire state of Kerala lie in this zone.