Swarms of earthquakes rock Southern California over 24 hours

[Kamaji]

Swarms of earthquakes rock Southern California over 24 hours

By Ronny Reyes   
April 30, 2023

A slew of earthquakes shook up the Salton Sea region of Southern California within 24 hours over the weekend, with the seismic activity reaching up to 4.5 in magnitude.

The first swarm began at 12:08 p.m. Saturday in the US-Mexico border town of Herber, with nearly 50 tremors shaking the area until 5:12 a.m. Sunday, the US Geological Survey reported.

The Herber quakes reached up to 3.7 in magnitude and were felt by about 60 people.

The second swarm struck nearly 40 miles north, by the town of Niland, where more than 25 tremors then shook the southeast shore of the Salton Sea starting at 12.09 a.m. Sunday.

Those earthquakes lasted until 5:28 a.m. and reached a higher magnitude of 4.5, which was felt by about 30 people, UGS said.

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Source:  https://nypost.com/2023/04/30/swarms-of-earthquakes-rock-southern-california/

[GtHawk]

In other California news, water is still wet. There are several areas in California that have these periotic earthquake swarms, possibly signaling stress relief and then subsiding for months and months. Things like this just don't worry me much, if they did I would be stressed out every day seeing as I live in a tsunami zone and liquefaction zone

[Kamaji]

In other California news, water is still wet. There are several areas in California that have these periotic earthquake swarms, possibly signaling stress relief and then subsiding for months and months. Things like this just don't worry me much, if they did I would be stressed out every day seeing as I live in a tsunami zone and liquefaction zone

A so-called swarm of small(er) earthquakes would probably be a good thing, given the tectonics in California generally, since I would hazard a guess that it would usually mean a more gradual release of stress over an extended period of time, rather than a sudden give-way that releases all of it at once.

[GtHawk]

A so-called swarm of small(er) earthquakes would probably be a good thing, given the tectonics in California generally, since I would hazard a guess that it would usually mean a more gradual release of stress over an extended period of time, rather than a sudden give-way that releases all of it at once.

Yup, and it makes those predicting the big one so sad. There are as I said areas like Salton Sea, Ridgecrest(huge swarm lasting quite a long time in 2019, Parkfield to Frisco and Cloverdale are almost always having small quakes. https://scedc.caltech.edu/recent/Maps/118-34.html
It's the norm i grew up with and why I would rather face a quake than tornadoes and hurricanes...I guess I'm prejudiced Now if we could only evict the democrats California could be a nice place again(Oregon and Washington too), but where to put them Cuba?

[bigheadfred]

@GtHawk  @Kamaji

I live fairly close to Yellowstone. There are earthquake storms there. My hope is that if it blows I never know it. And if it happens in the summer there are going to be a lot of Chinese tourists flying around.

[Smokin Joe]

Yup, and it makes those predicting the big one so sad. There are as I said areas like Salton Sea, Ridgecrest(huge swarm lasting quite a long time in 2019, Parkfield to Frisco and Cloverdale are almost always having small quakes. https://scedc.caltech.edu/recent/Maps/118-34.html
It's the norm i grew up with and why I would rather face a quake than tornadoes and hurricanes...I guess I'm prejudiced Now if we could only evict the democrats California could be a nice place again(Oregon and Washington too), but where to put them Cuba?

I would think that stress being relieved in one area is being transferred to another, but not being intimately familiar with the fault systems in the State can't say that for a fact.

[Kamaji]

I would think that stress being relieved in one area is being transferred to another, but not being intimately familiar with the fault systems in the State can't say that for a fact.

Yes, and no.  Since the crust and the tectonic plates are not perfectly elastic, a lot of the stress gets lost, not transferred, when it is relieved in one area; however, it is most likely correct that when one particular portion of a long fault lets go, that increases the stress on the next stoppage points (i.e., slip restriction areas), increasing the likelihood of a failure at that point.  However, since the system is not perfectly elastic, some of the released stress is "spent" in deforming rock and whatnot, which means that energy is no longer in the system, so the net effect is a relief of stress energy overall.

[Fishrrman]

I'm wonderin' how strong a quake it would take in San Francisco to topple the Millenium Tower over?
It's already leaning about 26" off-kilter to one side, and the supporting piles underneath don't go down to bedrock...

[corbe]