Seismologists have recorded a magnitude 5.6 earthquake in the United States, with the epicentre located 200 km SW of Port McNeill, Canada. The event occurred at 04:49 UTC on Saturday, August 1, 2026 and originated at a depth of 10.0 km.
Seismic Context for the United States
The United States experiences significant seismic activity primarily along the West Coast (Cascadia Subduction Zone, San Andreas Fault), in Alaska (subduction of the Pacific Plate), and in the intermountain West. The New Madrid Seismic Zone in the central US represents a significant intraplate hazard.
Alaska is the most seismically active US state, regularly producing large earthquakes including the 1964 Good Friday earthquake (M9.2 — the second largest ever recorded). California's San Andreas Fault system poses long-term risk to millions of residents. The USGS ShakeAlert early-warning system now covers the entire West Coast.
About This Event
At a focal depth of 10.0 km, this is classified as a shallow earthquake (0–70 km). Shallow events are typically the most damaging: the seismic energy has less distance to travel before reaching the surface, resulting in stronger and more abrupt ground shaking at the epicentre.
In terms of felt effects, a magnitude 5.6 earthquake is typically 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 Magnitude Scale
Earthquake magnitude is measured on a logarithmic scale — meaning each whole-number increase corresponds to roughly 32 times more energy released and approximately 10 times greater ground motion amplitude. A magnitude 5.6 event therefore releases significantly more energy than its number alone might suggest to the casual observer.
The energy released by a magnitude 5.6 earthquake is approximately the equivalent of a large mining explosion or small nuclear device. This is 32 times more energy than a magnitude 4.6 event — the logarithmic nature of the magnitude scale means each whole number increase represents about 32 times more energy.
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.
What to Do After an Earthquake
Agree on an out-of-area contact that family members can reach if local communications are disrupted. Identify two meeting points: one near your home and one further away. Practise earthquake drills, especially with children and elderly household members.
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.
Staying Informed
The USGS ShakeAlert system delivers earthquake warnings to smartphones via Wireless Emergency Alerts on the West Coast. California residents can also use the MyShake app. Drop, Cover, Hold On is the recommended protective action.
QuakeWatch publishes real-time earthquake data sourced from the USGS global catalog — covering every detected seismic event worldwide, 24 hours a day. Visit our live map to see this and all other recent earthquakes, or explore our guide to earthquake magnitude for a deeper understanding of what these numbers mean in practice.
Community Felt Reports
If you felt this earthquake, your experience contributes to an important scientific dataset. The USGS "Did You Feel It?" (DYFI) system and QuakeWatch's own community reports platform collect first-hand accounts of shaking intensity from people across the affected region. These reports — describing where people were, what they felt, and what moved or was damaged — help seismologists map shaking intensity across an area much larger than any single seismograph can cover. Visit the earthquake's detail page on our live map to submit your own report.
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