The USGS has confirmed a magnitude 4.5 earthquake with its epicentre 56 km SE of Tuensang, India, occurring at 23:09 UTC on Saturday, July 25, 2026. The event's focal depth — 93.0 km — is a key factor in understanding how this earthquake was experienced at the surface.
Why Depth Matters
With a focal depth of 93.0 km, this earthquake falls into the intermediate depth category (70–300 km). At this depth, seismic waves travel further before reaching the surface, spreading energy over a wider area. While shaking intensity at the epicentre is somewhat reduced compared to a shallow event of equal magnitude, an intermediate earthquake can be felt across a much larger region.
Depth is one of the most critical but least discussed parameters of any earthquake. Two earthquakes of identical magnitude can have dramatically different surface effects depending on how deep the rupture originates. Significant damage can occur to vulnerable structures — particularly unreinforced masonry, old adobe buildings, and poorly maintained older construction. Well-engineered modern buildings are designed to withstand this level of shaking with minimal structural impact, though contents may shift and non-structural elements (ceilings, partitions) can be damaged.
Magnitude 4.5: What the Science Says
On the moment magnitude scale, 4.5 represents a moderate earthquake. Moderate earthquakes are felt by virtually everyone near the epicentre. Strong shaking lasting 10–30 seconds can topple unsecured items, crack plaster, and cause poorly anchored objects to fall. Aftershocks are common following moderate events.
A magnitude 4.5 earthquake releases approximately roughly 500 tonnes of TNT of energy. For comparison, this exceeds the energy released by most conventional explosive events and is sufficient to shift tectonic stress in measurable ways across a wide region.
Tectonic Setting
India's seismic hazard stems primarily from the ongoing collision of the Indian Plate with the Eurasian Plate — a process that built the Himalayas and continues to drive intense seismicity across northern India, Nepal, and the Andaman Islands.
This region's seismic history is an important reminder that earthquake risk is a long-term reality that requires sustained preparedness. Notable Indian earthquakes include the 2001 Bhuj earthquake (M7.7, ~20,000 deaths) in Gujarat and the 2015 Gorkha earthquake centred in Nepal (M7.8, ~9,000 deaths) which was strongly felt across northern India. The densely populated Indo-Gangetic Plain, though not directly on a plate boundary, faces amplified shaking from distant Himalayan earthquakes.
Practical Safety Information
Regardless of the earthquake's depth or magnitude, standard safety procedures apply. If you are on or near a coast and experience strong or prolonged earthquake shaking, treat it as a potential tsunami warning and move immediately to high ground. Do not wait for an official alert — natural warning signs (severe shaking, unusual sea withdrawal) are your first alert.
Fasten heavy furniture — bookshelves, water heaters, cabinets — to walls using earthquake straps. Store breakable items on lower shelves and heavy items closest to the floor. These simple steps significantly reduce the risk of injury from falling objects.
The National Center for Seismology (NCS) under India's Ministry of Earth Sciences monitors seismic activity and maintains a network of ~100 seismograph stations across the country.
Track This Event
All seismic data for this event is being updated in real time as the USGS refines its measurements. Initial magnitude and depth estimates are sometimes revised as more seismograph stations report in — a process that typically completes within hours of the event. Follow updates on our live earthquake map and consider submitting a felt report if you experienced this earthquake directly.
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