Why in news?
Several medium‑intensity tremors in and around Delhi sparked discussions on the seismic vulnerability of the National Capital Region (NCR).
Factors contributing to vulnerability
- Proximity to active faults: NCR lies close to the Himalayan thrust zones and is criss‑crossed by local faults such as the Delhi–Hardwar Ridge and Mahendragarh–Dehradun fault.
- Historical seismicity: The region experienced moderate earthquakes in 1720, 1803, 1835 and 1956; a major Himalayan quake could cause severe damage.
- Soft soil amplification: Alluvial sediments of the Yamuna floodplain amplify seismic waves, increasing shaking intensity.
- Unplanned urbanisation: High population density, vertical expansion without seismic design and encroachment on riverbeds compound risk.
- Preparedness gaps: Building code compliance and earthquake‑resistant construction are often ignored, and emergency response systems need strengthening.
Way forward
- Enforce seismic‑resistant designs, retrofit old structures and restrict construction in high‑risk zones.
- Enhance public awareness through drills and early‑warning systems.
- Develop microzonation maps to guide urban planning and allocate resources for disaster preparedness.
