M6.0 Earthquake Hits Japan — What We Know

A magnitude 6.0 earthquake struck Japan at 22:15 UTC on Saturday, October 31, 2026, with its epicentre recorded 58 km SSE of Shima, Japan at a depth of 352.4 km. If you felt this earthquake, you are not alone — and your experience is scientifically valuable.

Did You Feel It?

Community felt reports are an important part of modern earthquake science. The USGS "Did You Feel It?" (DYFI) system collects reports from people who experienced shaking, generating intensity maps that complement instrumental data. These reports help seismologists understand how shaking varied across the affected region and can improve earthquake hazard assessments.

A magnitude 6.0 earthquake is capable of causing significant damage, particularly to older or poorly built structures. Strong earthquakes cause severe shaking that is difficult to stand through. Duration can reach 30–60 seconds. Widespread damage to ordinary buildings is common; even some well-built structures may sustain damage. Strong ground motion can trigger landslides, liquefaction of saturated soils, and rupturing of underground infrastructure.

Understanding the Event

At a focal depth of 352.4 km, this is a deep earthquake (below 300 km), occurring well within Earth's mantle. Deep earthquakes are a distinctive feature of subduction zones where cold oceanic crust descends into the mantle. Despite the large magnitude, the extreme depth means surface shaking is distributed over a vast area and is considerably less intense at any single point than a shallow event of equivalent magnitude.

The energy released by a magnitude 6.0 earthquake is approximately roughly 1 million tonnes of TNT — equivalent to a major nuclear weapon. This is 32 times more energy than a magnitude 5.0 event — the logarithmic nature of the magnitude scale means each whole number increase represents about 32 times more energy.

Why Here? The Geology Behind the Earthquake

Japan sits at the convergence of the Pacific, Philippine Sea, Eurasian, and North American tectonic plates, making it one of the most seismically active countries on Earth.

Japan experiences roughly 1,500 earthquakes per year that are strong enough to be felt. The country has developed one of the world's most sophisticated earthquake early-warning networks, capable of alerting millions of citizens within seconds of a major rupture.

Structural Considerations

This magnitude class poses a serious threat to older and poorly constructed buildings. Collapse is possible in the most vulnerable structures. Modern seismically designed buildings are expected to remain standing, though repair or demolition may be necessary after inspection.

If you are in the affected area and notice damage to your building — cracks in load-bearing walls, shifted foundations, or distorted door frames — treat this as a potential sign of structural compromise and seek professional assessment before resuming normal occupation.

Safety Reminders

Keep an earthquake emergency kit accessible at home. It should include at least 72 hours of water (4 litres per person per day), non-perishable food, a first aid kit, torch, battery-powered radio, copies of important documents, and essential medications. Reviewing and restocking this kit annually is strongly recommended.

After an earthquake, expect aftershocks. Check yourself and others for injuries. Inspect your surroundings for hazards before moving — broken glass, gas leaks (smell), downed power lines, and structural damage. If you suspect a gas leak, open windows and evacuate without using electrical switches or open flames.

If you are in Japan, follow J-Alert instructions and refer to local municipal evacuation maps. Many buildings constructed after the 1981 revised building code are designed to withstand strong shaking.

Share Your Experience on QuakeWatch

You can submit your own felt report directly on this earthquake's detail page on QuakeWatch. Your input — describing intensity, location, and what you observed — contributes to a richer picture of how this earthquake affected communities across the region. Visit our live map and click on this event to add your report.