A 5.9 magnitude earthquake struck off the Oregon Coast at 1:11 p.m., the fifth quake to hit the area since early Monday morning.
The earthquakes shook about 300 miles off the coast. More could still follow.
The first — a 5.8 magnitude earthquake — hit after midnight, six miles underground, which is considered relatively shallow, according to the U.S. Geological Survey.
A 5.9 magnitude earthquake has hit off the Oregon Coast, making it the fifth quake to shake the area Monday.
USGS
An hour later, a 4.8 hit in the same spot. Five hours later, there was a 5.5, and a 4.4 quake at 9:45 a.m.
USGS scientist Harley Benz says the series is related to the Cascadia Subduction Zone. But rather than being in an area where one tectonic plate is being pushed under another, it’s happening in an area where the two plates slide next to each other.
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"You'll probably see a few more and then it'll die off after time," says Benz. "That's pretty typical. There is a small probability of having an earthquake of a similar size."
He says quakes often happen in this area.
No tsunamis were triggered and no damage has been reported.