Earthquake Swarm in South Reno
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NV Seismology Lab (Emphasis added)
The area at the base of Mount Rose got hit with 20 quakes in the first three days, the biggest a 3.0.\
A new swarm gets everybody's attention in Reno because of what happened a couple years ago.
In early 2008 people in the Mogul and Sommerset areas of northwest Reno started to notice some small quakes- magnitude 1 and 2. Instead of weakening, they grew stronger.
The swarm culminated with an April quake that registered 4.7 which did a lot of structural damage.
It had people on pins and needles for the better part of a year, wondering if there was more to come.
So what about this new swarm in South Reno? Seismologist Graham Kent says there's only a tiny chance it'll get stronger.
Kent: "Most of them just die out on their own, but we do worry, we've seen in other places where they can jump on to a larger fault zone and take off into larger ruptures."
And if this swarm goes that way... it could cause problems. The quakes are striking deep- but near to the meeting point of some faults that come down from Incline Village and others known as the Mount Rose Fan Faults, which have produced major quakes in the last few thousand years.
Swarms are a newer area of study in seismology because it takes modern equipment to track them, but Kent's noticed a trend in swarms that grow bigger. They tend to crank out multiple magnitude 3 or larger foreshocks in the span of an hour or two... before the main quake comes.
Since that hasn't happened at this point, I asked Kent if he's any more concerned about the possibility of a major quake now than he would be on any other day.
Kent: "In the background I'm just as worried about something rupturing in Carson City or out near Pyramid Lake or in Truckee. We have so many different places that can sustain high 6 - low 7 magnitude events."
Kent points out big quakes can happen with or without a swarm.
Even though the swarms can put people on pins and needles... they may actually beneficial. Kent has a theory that the swarms spread out the release of tension in the earth's crust. Perhaps instead of one large quake...
Kent: "You can break it up across a number of smaller earthquakes, maybe that's a good thing."
Like all things seismological, there's a lot of guessing to this stuff. The seismologists advice? Wake up every day prepared for a big one- swarm or no.