According to India's seismic zoning map, the Andaman and Nicobar Islands fall in which seismic zone?

The Andaman and Nicobar Islands lie in Seismic Zone V, the zone of the highest earthquake risk in India.

Why the islands are in Zone V:

• They lie along the boundary where the Indian Plate sinks beneath the Burma microplate.
• This plate boundary has produced very large earthquakes.
• The great Sumatra-Andaman earthquake of 26 December 2004 (magnitude 9.1) caused severe damage in the islands, lifting some areas and sinking others.

India's seismic zones (IS 1893 code):

India's seismic zoning map, prepared by the Bureau of Indian Standards (BIS), has traditionally divided the country into four zones, II, III, IV and V. The earlier Zone I was merged into Zone II in 2002.

Zone II: low damage risk, such as much of the Deccan plateau.

Zone III: moderate risk, such as Kerala, Goa and Lakshadweep.

Zone IV: high risk, such as Delhi, Ladakh and Sikkim.

Zone V: very high damage risk. Includes the whole of the north-eastern region, parts of Jammu and Kashmir, Himachal Pradesh and Uttarakhand, the Rann of Kutch in Gujarat, north Bihar and the Andaman and Nicobar Islands.

The BIS revises the seismic code from time to time as new data become available.

Measuring earthquakes:

• Magnitude, which measures the energy released, is given on the Richter scale or, more commonly today, the moment magnitude scale.
• Intensity, which measures the effects and damage at a place, is given on the Modified Mercalli scale.
• The National Center for Seismology (NCS), under the Ministry of Earth Sciences, monitors earthquakes in India.

Earthquake safety:

• Buildings in high-risk zones must follow earthquake-resistant design codes.
• About 59 percent of India's land area is vulnerable to moderate to severe earthquakes.
• Good to know
• Zones II, III and IV represent lower levels of earthquake risk than Zone V.