A magnitude 5.5 earthquake struck the Pacific 218 kilometers west of Bandon, Oregon, at 11:35 UTC on June 29, 2026. That was 4:35 a.m. local time on a Monday. The USGS put the depth at 10 kilometers, and the epicenter sat about 185 miles southwest of Eugene.
No tsunami followed. At around 5 a.m., the U.S. National Tsunami Warning Center posted that none was expected. The USGS assigned its lowest, green PAGER alert, which signals minimal risk of damage and injury.
Seventeen people reported feeling the tremor across coastal Oregon and northern California. Observers as far as 300 km away noted it. Communities from Bandon to Port Orford, and inland to Grants Pass, felt light shaking at Modified Mercalli Intensity III to IV. No structural damage was reported.
Where it happened
The quake occurred within the Blanco Fracture Zone, a right-lateral strike-slip fault system that runs northeast to southwest off the Oregon coast. It takes up motion between the Juan de Fuca and Pacific plates, which slide past each other at roughly 4.6 cm a year. That puts the event outside the primary Cascadia subduction zone.
The distinction matters for tsunamis. Strike-slip faults rarely displace water vertically, and horizontal motion generates minimal wave energy. Deep subduction ruptures like those on the Cascadia megathrust pose genuine tsunami hazards. This event did not.
Magnitude 5 to 6 events are routine here. The zone produces 15 to 20 earthquakes of magnitude 5.0 or greater per decade. Earlier Blanco events include a magnitude 5.9 in 2005 and a magnitude 5.2 in 2016, both with minimal effects.
Why people felt it
Depth explains the reach. A 10 km hypocenter lets waves travel efficiently through crustal rock to the surface, and shallow shocks send energy upward more effectively than deep ones. At 100 km, ground acceleration can pass 0.05g, enough to rattle dishes and unsettle people but rarely enough to hurt modern buildings.
The energy release works out to roughly 5.6 × 10¹⁴ joules, comparable to 134 kilotons of TNT.
Distance from shore did the rest. With the rupture 218 km from populated areas, there was little chance of serious infrastructure damage. Had the same quake hit beneath a populated area, damage would have been significant.
