Solution:On the basic of data provided by Indian Meteorological Department and other agencies, Bureau of Indian Standards has published the latest version of seismic zoning map of India. The earthquake resistant design code of India assigns four level of seismicity zone factors of India. India is divided into four seismic zones on the basic of earthquake intensity-namely zone 2, zone 3, zone 4 and zone 5.
The Intensity of earthquake in different zones:| Seismic Zone | Intensity on Modified Mercalli scale |
| Zone II (Low-intensity zone) | VI (or less) low
damage |
| Zone III (Moderate intensity zone) | VII damage to buildings |
| Zone IV (Severe intensity zone) | VIII destruction of buildings |
| Zone V (Very severe intensity zone) | IX (and above) very high damage |
Zone V: Zone V covers 10.9% area of the country with the highest risks zone that suffers earthquakes of intensity MSK IX or greater. The IS code assigns zone factor of 0.36 for Zone V. Structural designers use this factor for earthquake resistant design of structures in Zone V. The zone factor of 0.36 is indicative of effective (zero period) level earthquake in this Zone. It is referred to as the very high damage risk zone. The region of J & K (UT), Ladakh (UT), Western and Central Himalayas, North and Middle Bihar, North-East Indian region and the Rann of Kutch fall in this zone.
Zone IV: This Zone is called the High Damage Risk Zone and covers the area liable to MSK VIII. The IS code assigns zone factor of 0.24 for Zone IV. The Indo-Gangetic basin and the capital of the country (Delhi), rest of Himalayas is included in Zone IV. In Maharashtra, the Patan area (Koyananagar) is also in Zone IV. This Zone covers remaining parts of Himachal Pradesh, Sikkim, Northern parts of Uttar Pradesh, Bihar and West Bengal, parts of Gujarat and small portions of Maharashtra near the West coast and Rajasthan. It comprises 17.3% areas of the country.
Zone III: The IS code assigns zone factor of 0.18 for Zone III. It covers the Lakshadweep islands. This Zone is classified as Moderate Damage Risk Zone. It includes 30.4% areas of the country.
Zone II: The IS code assigns Zone factor of 0.10 (maximum horizontal acceleration that can be experienced by a structure in this Zone is 10% of gravitational acceleration) for Zone II. It comprises 41.4% areas of the country.
Major parts of the peninsular region and Karnataka Plateau fall in this Zone. Thus, it does not come under the Zone of high seismic intensity.
