A magnitude 5.3 earthquake struck off the Oregon coast Wednesday morning according to the USGS.
The 8am shaker was centered about 175 miles west of Reedsport, with litttle or no noticeable shaking on shore.
The epicenter of the quake was at a depth of nearly 9 miles inside the Blanco Fracture Zone, where earthquake activity is very common.
Seismologists say the frequent rumblings are not necessarily indicative that a larger earthquake is imminent along the nearby Cascadia Subduction Zone (CSZ). However, the CSZ can produce huge tsunamis that can race ashore after the shoreline has fallen in elevation due to the “Big One.” Geologists and Seismologists remind everyone that Coastal Oregon is ground zero for very substantial earthquake activity.
The last big Cascadia “event” was on January 26th, 1700. A huge tsunami raced across the northern Pacific and swamped villages and towns along the eastern Japanese coast. They called it the “Orphan Tsunami” because no one felt an earthquake that could have caused such a destructive wall of water.
Meanwhile, back on the northwest coast of the U.S. the beaches sank 10 to 20 feet, killing trees that grew along the western edges of near-shore forests. The dead tree stumps are clearly visible during very low tides. The Cascadia Subduction Zone has a habit of triggering such quakes every 250 to 350 years. From 1700 to 2019 is well within the quake’s powerful reach, if not near the outer edge of the time intervals between such quakes.