Geography – Earthquakes & Seismic Vulnerability in India

✅ GS Paper-I: Geography – Earthquakes & Seismic Vulnerability in India

🔹 Introduction

• On July 10, 2025, a 4.4 magnitude earthquake hit Delhi — a stark reminder of India’s seismic vulnerability.

• India lies on a tectonically active plate, where the Indian Plate collides with the Eurasian Plate, causing frequent earthquakes, especially in the Himalayan belt.

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🔹 Why India is Seismically Vulnerable

1. Plate Tectonics

   • Indian Plate moving northward at 4–5 cm/year

   • Collision creates intense seismic pressure, especially in the Himalayas.

2. Seismic Zones (IS 1893:2016)

   • Zones II to V based on Peak Ground Acceleration (PGA)

   • Zone V: Very high risk (≥0.36g) – e.g., NE states, Andaman, Kutch

   • Delhi: In Zone IV (0.24g) with poor compliance to codes.

3. Urban Fragility

   • 80% of buildings in Delhi (pre-2000) not seismic-code compliant

   • East Delhi built on liquefaction-prone soil

   • Unregulated urbanisation adds to risk.

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🔹 Key Examples of Past Earthquakes

Event	Year	Magnitude	Impact
Bhuj (Gujarat)	2001	7.7	20,000+ deaths
Nepal (Gorkha)	2015	7.8	Massive infrastructure loss
Andaman Quake	2004	9.1	Triggered Indian Ocean tsunami

🔹 Impact of Global Seismic Events on India

• Myanmar-Thailand quake (7.7), Tibetan quake (5.7), and others reflect regional tectonic stress.

• Even distant quakes (e.g. Greece, May 2025) signal global seismic unrest, though impact on India is minimal.

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🔹 Conclusion (GS-I)

India’s seismic zones cover a vast and growing urban population. With rising urban density, poor planning, and non-compliance, the risk is amplified. A tectonic shift in policy and preparedness is essential to avoid catastrophe.