Why this matters now
Seismic zoning is a Prelims item, and earthquakes are a key GS-3 disaster-management theme — risk lies less in the quake than in poorly built structures, making building codes and preparedness central.
Why India is seismically active
The Indian Plate is still moving north and subducting beneath the Eurasian Plate, building stress along the Himalayas that releases as earthquakes. Hence the Himalayan belt (and the north-east, Kashmir) is the most active. India also has intraplate seismicity — the devastating Bhuj (Gujarat) earthquake of 2001 struck within the plate, in the Kutch region.
The four seismic zones
| Zone | Hazard | Examples |
|---|---|---|
| Zone V | Highest (very severe) | North-East, Kashmir, Himachal/Uttarakhand Himalaya, Kutch, Andaman & Nicobar |
| Zone IV | High | Delhi-NCR, parts of the Indo-Gangetic plains, J&K |
| Zone III | Moderate | Much of the peninsula’s margins, parts of central India |
| Zone II | Low | Stable parts of the Peninsular Plateau |
(India’s earlier 5-zone map was revised to four zones, II-V, by the BIS.)
Risk reduction
Because most earthquake deaths come from building collapse, mitigation focuses on seismic-resistant design and building codes (BIS), retrofitting, microzonation of cities, public awareness, and NDMA guidelines. India also contributes to seismic monitoring through the National Centre for Seismology.
UPSC angle
Remember the 4 zones (II-V; V highest = NE/Himalaya/Kutch/Andaman), the plate-collision cause, the intraplate Bhuj 2001 event, and that risk reduction centres on building codes.
Frequently asked questions
Why is India prone to earthquakes?
Because the Indian Plate is subducting beneath the Eurasian Plate, building stress along the Himalayas; India also has intraplate seismicity (e.g., Kutch).
How many seismic zones does India have?
Four — Zones II to V, mapped by the Bureau of Indian Standards by increasing hazard (Zone V is the highest).
Which areas fall in Zone V?
The North-East, Kashmir, the Himachal/Uttarakhand Himalaya, the Kutch region of Gujarat, and the Andaman & Nicobar Islands.
How can earthquake risk be reduced?
Mainly through seismic-resistant building design and codes, retrofitting, city microzonation and public preparedness, since most deaths come from collapsing structures.