Earthquake Zones of India – UPSC & SSC Exam Notes | JKSSB Mock Test
🌍 Earthquake Zones of India
🔹 Introduction
India lies at the intersection of the Indian Plate and the Eurasian Plate, making it one of the most seismically active regions in the world. Earthquakes have been a recurring hazard in various parts of the country. To assess and mitigate this risk, the country is divided into different seismic zones.
🔹 Causes of Earthquakes in India
- Plate Tectonics: Collision of the Indian Plate with the Eurasian Plate causes seismic activity.
- Fault Lines: Movements along faults like the Himalayan Frontal Thrust and Main Boundary Thrust.
- Volcanic Activity: Rare in India but can trigger minor tremors (e.g., Andaman region).
- Human Activities: Mining, dam construction, and groundwater extraction can induce seismicity.
🔹 Seismic Zoning in India
The Bureau of Indian Standards (BIS) has divided the country into four seismic zones in IS 1893 (Part 1): 2002. Earlier there were five zones, but Zone I was merged into Zone II.
| Zone | Description | Zone Factor | Damage Risk |
|---|---|---|---|
| Zone II | Low seismic risk | 0.10 | Low |
| Zone III | Moderate seismic risk | 0.16 | Moderate |
| Zone IV | High seismic risk | 0.24 | Severe |
| Zone V | Very high seismic risk | 0.36 | Very Severe |
🔹 Zone-Wise Coverage
📍 Zone V – Very High Risk
- Covers areas with the highest intensity of earthquakes (MSK IX and above).
- Includes: North-East India, parts of Jammu & Kashmir, Uttarakhand, Bihar (North), and Andaman-Nicobar Islands.
📍 Zone IV – High Risk
- Regions experience damaging earthquakes (MSK VIII).
- Includes: Delhi, Punjab, Haryana, parts of Uttar Pradesh, Himachal Pradesh, Gujarat, and West Bengal (North).
📍 Zone III – Moderate Risk
- Regions face occasional strong tremors (MSK VII).
- Includes: Maharashtra, Kerala, Goa, parts of Madhya Pradesh, Andhra Pradesh, and Odisha.
📍 Zone II – Low Risk
- Least seismically active; minor tremors (MSK VI or lower).
- Includes: parts of Karnataka, Telangana, Tamil Nadu, and central India.
🔹 Major Earthquakes in India (Historical)
| Year | Location | Magnitude | Impact |
|---|---|---|---|
| 2005 | Muzaffarabad (J&K) | 7.6 | Thousands killed, widespread damage |
| 2001 | Bhuj, Gujarat | 7.7 | ~20,000 deaths, major infrastructure collapse |
| 1993 | Latur, Maharashtra | 6.2 | ~10,000 deaths, unexpected area |
| 1950 | Assam-Tibet | 8.6 | One of the strongest ever recorded in India |
| 1905 | Kangra, Himachal | 7.8 | ~20,000 deaths |
🔹 Map of Seismic Zones of India
A map is often asked in exams. It shows:
- Zone V – Red (Most vulnerable)
- Zone IV – Orange
- Zone III – Yellow
- Zone II – Blue (Least vulnerable)
Markings are especially useful for quick revision and mapping-based MCQs.
🔹 Why North-East India is Most Vulnerable?
- Located at the junction of the Indian and Burmese plates.
- Frequent seismic movements and shallow-focus earthquakes.
- Historical data shows frequent quakes above 6.0 magnitude.
🔹 Earthquake Preparedness in India
- NDMA (National Disaster Management Authority) issues guidelines.
- BIS Codes regulate earthquake-resistant building construction.
- Disaster drills and community awareness programs.
- Inclusion of disaster education in schools and colleges.
🔹 Urban Vulnerability & Risk
- High-rise buildings and dense populations increase impact.
- Delhi, Guwahati, Srinagar are highly vulnerable urban centers.
- Poor construction standards and unregulated urban growth compound risks.
🔹 UPSC/SSC/JKSSB PYQs
- Q1: Which zone has the highest seismic risk?
👉 A. Zone V ✅ - Q2: Which city lies in Zone IV?
👉 A. Delhi ✅ - Q3: What is the magnitude of the 2001 Bhuj earthquake?
👉 A. 7.7 ✅ - Q4: Which BIS code deals with seismic zoning?
👉 A. IS 1893 ✅
🔹 People Also Ask (FAQs)
- Q: How many seismic zones are there in India?
A: Four – Zone II to Zone V. - Q: Which part of India is most earthquake-prone?
A: North-East India and Himalayas. - Q: Is Delhi in an earthquake zone?
A: Yes, in Zone IV. - Q: Which was the deadliest earthquake in India?
A: Bhuj (2001) in recent history; Assam (1950) was strongest.
🖚 Conclusion
Understanding the earthquake zones of India is crucial for disaster preparedness, planning, and safety. From Zone II to Zone V, every region has its own risk profile. For exams, remember the zone-wise states, major historical quakes, seismic codes, and the role of NDMA.
