A 3.8 Earthquake Strikes Snoqualmie Pass. Is the Big One Next?

On a Tuesday, August 8th at about 3:17 in the morning Pacific time there was a magnitude 3.8 earthquake around 5 miles northeast from Fall City, Washington. The quake was on the more shallow side of earthquakes, at about 10 miles deep.

This magnitude was enough for many people to get woken up by shaking windows, or doors, with many reporting feeling it in their beds. As of this report, the USGS has received over 1,100 reports of felt shaking throughout the region.

"It's actually, perhaps something we would call a shallower earthquake, at 10 miles. Although we do see earthquakes that are more shallow; 6 miles, 3 miles the closer to the surface." says USGS scientist Mouse Reusch.

She says that when an earthquake happens more shallow that we feel the shaking at the magnitude this quake was. If it were the same size, but deeper, it's less likely to be felt.

"For example, the Nisqually earthquake in 2001 was about 50 miles deep, but because it was a magnitude 6.8 that was still widely felt at the surface and for many miles in all directions" she adds.

Globally we do see earthquakes that are much deeper; in the 100s of miles. But they would usually happen offshore or in subduction zones.

The largest aftershock so far has been a magnitude 2.8, but most of the other ones have been very small. A couple around 2.0, 1.9, 0.7, etc. That being said, is not unexpected for earthquakes in that region. According to the USGS, since August 1st of 2000 there have been 13 earthquakes that have been larger than a magnitude 3; between three and four, in fact.

As to whether, or not this is a sign of the "big one"... no. No it isn't. However it is just a matter of time before that does happen. More than likely within a lot of our lifetimes.