Srinagar, Dec 27:
A massive geological “tearing” of the Indian tectonic plate deep beneath the Tibetan Plateau is reshaping the seismic future of the Himalayas. In response to this evolving threat and modern hazard modeling, the Bureau of Indian Standards (BIS) has officially elevated Jammu & Kashmir to Seismic Zone VI—a newly created category for the highest possible earthquake risk.
The move, part of the 2025 National Seismic Hazard Map released in November, signals that the region faces a more “precarious geological reality” than previously understood.
A landmark study titled ‘The Indian Plate subducting below the Tibet Plateau is tearing apart’, published in Communications Earth and Environment (August 2025), reveals that the Indian plate is not sliding as a single, solid slab. Instead, it is splitting and “delaminating” (peeling apart).
Situated in the eastern Himalayas (90-92°E longitude). As the Indian plate subducts, its dense lower mantle is peeling away and sinking, while the upper crust remains engaged in a high-friction collision with the Eurasian plate. While the physical tear is to the east, the process redistributes extreme tectonic stress along the entire 2,500km Himalayan arc. In J&K, the plate remains “underplated” (intact but jammed), building up massive strain that experts warn could be released in a Magnitude 8.0 or greater event.
Until recently, Zone V was considered the most dangerous classification in India. The introduction of Zone VI reflects a new scientific consensus that the Himalayan arc requires its own unique, extreme risk category.
The 2025 map revision marks the first time India has moved away from historical data alone, opting for Probabilistic Seismic Hazard Assessment (PSHA). This method accounts for “Seismic Gaps”—areas like the central Himalayas that haven’t had a major quake in centuries and are “overdue” for a massive release of energy.
“The 2005 magnitude 7.6 earthquake was a wake-up call, but the energy currently stored in the Main Himalayan Thrust is significantly higher,” experts noted. “Zone VI isn’t just a label; it’s a mandate for a total overhaul of how we build in J&K.”
The reclassification has immediate implications for the region’s massive infrastructure push: New studies suggest tunnels must now be designed for PGA values of 0.5g or higher. Buildings in Srinagar and Jammu must adhere to the IS 1893:2025 Earthquake Design Code, which includes new rules for “non-structural” elements like ceilings and power lines that often cause secondary casualties.
