No cause for alarm after 5 earthquakes hits 100 miles off Oregon coast, or is there?

No cause for alarm after 5 earthquakes hits 100 miles off Oregon coast, or is there?

Nov 17, 2018 – Multiple earthquakes hit in the Pacific Ocean off the southern Oregon coast Thursday night and Friday morning, but there’s no cause for alarm.




 

A magnitude-4.5 quake, largest of the five, happened about 9:22 p.m. Thursday. The quake happened about 112 miles from Port Orford, according to the U.S. Geological Survey.

The other quakes, which happened in the same general area, measured between magnitudes 3.5 and 4.1.

Depends on what scientist you talk to about the threat this might signal in the future.

Chris Goldfinger, a professor and earthquake geologist at Oregon State University, said the earthquakes serve as a reminder that we live in a subduction zone but are nothing to worry about.

But, seismo.berkeley.edu say’s this.
“If you look at earthquake statistics in most regions of the world, including California, you will find that for every magnitude 5 earthquake, there are about 10 that have a magnitude of 4, and for each magnitude 4, there are 10 with magnitude 3.

Unfortunately, this means there are not enough small earthquakes to relieve enough stress to prevent the large events. In fact, it would take 32 magnitude 5’s, 1000 magnitude 4’s, or 32,000 magnitude 3’s to equal the energy produced in one magnitude 6 event.”

Earthquakes happen in this area all the time, he said. But he said there’s no direct link between these earthquakes and the so-called “big one” — and if anything, they relieve a bit of internal stress in the Gorda Plate, which covers the area, instead of increasing it.

Magnitude-4 earthquakes are felt by humans and may cause damage, according to the Pacific Northwest Seismic Network.

Port Orford is a small city in Curry County on the Oregon coast.

Mary Greeley News
www.marygreeley.com

credit: https://www.oregonlive.com/earthquakes/index.ssf/2018/11/45-magnitude_earthquake_hits_p.html
http://seismo.berkeley.edu/outreach/faq.html