Strongest earthquake in years rattles Southern California | Hacker News Reader

Strongest earthquake in years rattles Southern California

latimes.com

169 pointsjaredwiener90 comments

Note that this quake was not on the San Andreas - it was in the Eastern California Shear Zone, a separate fault system near Death Valley. The epicenter was about 125 miles away from LA, and almost closer to Las Vegas (which also felt this quake). The limited damage was largely because it was far away from any populated areas - the nearest cities are Ridgecrest (pop 27,000) and Trona (pop < 2000).

Also the area used be have some volcanic activity which is now limited to hot springs and geothermal plants. But you can still see a lot of lava fields when you drive there.

https://en.wikipedia.org/wiki/Coso_Volcanic_Field

It was also felt in Fresno, which is probably the furthest north large city (pop 500k) in the region.

https://earthquake-report.com/2019/07/04/moderate-earthquake...

I felt this (near Caltech, Pasadena). I spent the entire duration trying to figure out what was shaking my desk.

I hope this doesn't trigger anything larger. Does anybody know if this was close enough to the fault line to possibly affect anything?

EDIT: I see they have updated the article to a 1 in 20 chance.

[1] https://earthquake.usgs.gov/earthquakes/map/ [2] https://earthquake.usgs.gov/earthquakes/eventpage/ci38443095...

It was felt all the way out to the west coast (which is where the big fault line is). To answer your question, only time will tell.

I was only a few miles away in San Gabriel and did not feel a thing; I wonder if the SGV blocked any of the waves.

Wish I had come to campus early today to feel that one.

For anyone wondering, SGV refers to the San Gabriel Valley. (Correct me if I got it wrong.)

You got it right! (Though Pasadena is also in the SGV.)

I felt it in South Pasadena, but it was very gentle; would have been easy to miss if I hadn’t been sitting still when it happened.

Apparently, mountains buffer the waves. SGV is bordered by a San Gabriel mountain range. So, your experience sounds reasonable to me.

I'm in the mountains in San Bernadino (Lake Arrowhead / Big Bear) and I felt it pretty good. Shook the door to the bathroom. Thought my wife was being impatient.

Small earthquakes are a good thing, not a bad thing. They relieve stress on the fault without having a major slippage. I think.

The stress-relief model makes sense to me, but apparently it doesn't work that way:

https://www.sfgate.com/earthquakes/article/do-minor-quakes-p...

It does, and the article affirms this. However it's a question of relative magnitude. The energy dissipated by the smaller quakes is dwarfed in comparison to larger quakes. The energy of a 5.5 quake is on the order of 1/1000th the energy of a mag 7 quake.

I guess things didn't end up working that way today. Or maybe the 6.4 prevented the 7.1 from being even stronger :(

"Only 10 percent of California's 7 million plus homeowners have earthquake insurance – and the number has dropped by more than half since the deadly quake" (2014)

You can get an estimate for an earthquake insurance policy with the California Earthquake Authority.

[1] https://www.nbcnews.com/news/investigations/why-do-so-few-ca... [2] https://www.earthquakeauthority.com/

I understand why people keep bring up earthquake insurance, but it's not that many of us haven't considered it. It can be expensive to the extent that you are better off reinforcing your home rather than spending any money on said insurance. "The expensive deductible related to earthquake insurance are sometimes as high as 15% of the value of the home, which has many homeowners giving the insurance a second thought."[1]

Most insurance companies bailed out of the business of earthquake insurance after Northridge because when it happens, the claims are enormous. The 1906 San Francisco Earthquake was an indirect factor that lead to the Panic of 1907 due to the high volume of insurance claims.

[1]https://www.marketwatch.com/story/25-years-after-bay-area-qu...

When I looked into it, adding on earthquake insurance would cost more than my regular homeowners insurance, and like you said would still have a huge deductible without even covering most of my belongings

Furthermore, if a big quake happens, insurance companies are going to go broke paying out claims. Homeowners are going to be at the back of the line meaning most of them aren't going to see a dime.

I think the general consensus is that you'd be better using your money to get a construction loan to brace and bolt your home to resist earthquakes. I was quoted $175/month for earthquake insurance. That translates into a $25-30k loan. You can do a lot of structural improvement for that.

But...did you? Do the structural adjustments I mean.

I'm not clear how a CEA policy makes financial sense for a standard single-family, owner-occupied house. The only affordable plans have massive deductibles and only partial cost coverage. If "the big one" hits, it's likely that:

(a) CEA will quickly run out of money and I won't be covered anyway.

(b) The whole community will be ruined so assuming all of my family is still alive we'd best move somewhere else anyway (and a rebuild or undamaged house wouldn't sell).

For smaller earthquakes, it's likely I'd either fail to meet my deductible or be unable to pay the non-covered portion (which has to be paid out first before they'll begin to pay for further repairs).

Am I wrong, or is there something I'm missing? I wish this weren't the case.

Different country, but for the Christchurch earthquake in 2011:

- our equivalent of CEA (EQC) did indeed run out of money, although it’s mostly reinsurance and govt backed

- insurance companies went under, because even for a small city (400k), costs ran to $40 billion

- it’s now very very expensive to get earthquake coverage, in some parts of the country you are paying multiples of what less earthquake prone parts of the country pay, so people don’t bother. so they’ll lose everything next time, and we’ll foot the bill as a country

Scale of California probably means amplification if these effects, hundreds of billions in losses.

This. The CEA is not government-backed.

> CEA will quickly run out of money and I won't be covered anyway.

I don’t understand why insurance companies can run out of money whenever they need to pay claims. I’m sure they know they’re going to go under, why can’t they get insurance on themselves?

What’s the incentive to purchase insurance? It will reduce their profits. If you are an executive of a company offering earthquake insurance, better to just keeps profits high now, make a high salary, and when the big quake hits, declare bankruptcy and walk away.

They'll take a hit in their ratings if they do. Insurance companies are rated by independent analysts such as A.M. Best, Moody's, and Standard and Poor's. Customers, especially large customers, research issuers before purchasing insurance, and a poorly-rated company is likely to get fewer customers.

they're much more sophisticated than that. they'll do things like say the damage was caused by wind, not water. they'll influence forecasters to call it a "super-storm" instead of a hurricane, and for an earthquake, something equally creative:

- the building was defective/you didn't have it inspected by our experts, so maybe the foundation already had cracks from the last EQ, in that case we can't pay the claim

- insurance only covers up to 5.0/6.0

- although it was reported as a 7.5, you live 4 miles away from the epicenter, meaning the EQ was likely below a 6.0, in which case your policy doesn't kick in/we'll only pay 30% of your claim

- the EQ cracked a water main/gas line, and most of the damage to your house is from the flood/fire, which isn't covered under EQ policy. try suing the insurance of the utility company.

- we determined that fracking is likely the cause of this quake, in which case it's manmade and not covered. you can sue the oil company though.

- we checked the seismometer and we dispute the USGS reporting that it was a 6.0/7.0/8.0/our geologist has published research saying that current methods of measuring earthquakes are in question. so although we don't need correct science to collect your premium, we do need perfect science to pay any claims. Or if you settle now, we'll pay 40% of your coverage or else you can try to sue us and maybe get paid 10 years from now

- we don't cover the specific region where all the earthquake damage occurred/that requires a different policy

- we only cover incidental/secondary damage, like clocks falling off the wall (which, of course, you must have a receipt for and will be paid minus depreciation and deductible). your policy doesn't cover utility line damage, structural damage, or earth-moving damage.

They do, in fact! It's called reinsurance, and Gen Re (owned by Berkshire Hathaway) is one of the biggest issuers of reinsurance.

Alright, I'll bite. Does anybody issue insurance for the reinsurers?

Insurers often issue reinsurance for/with each other.

Both insurers and general reinsurance firms will some times sell their risk to investors (in the capital markets) through vehicles such as Insurance Linked Securities. An ILS provides one form of risk transfer. There are others.

In both cases, if the risk is tied to say, catastrophe insurance, then this offers (investors) returns uncorrelated with the stock market.

Unfortunately not. It's not insurance all the way down. Turtles, on the other hand ...

https://en.m.wikipedia.org/wiki/Turtles_all_the_way_down

Most insurance works on the basis that we have some underlying risk (probability) and resulting cost (multiplied together gives us the expectation) of annual payout. A lot of these funds however are financed through CAT bonds [1]. The idea of CAT bonds is that the sort of financial business cycle (a la 2007/8 housing market crash) are decorrelated enough with other financial movements that you "shouldn't™" both have a bad natural disaster and a sudden shift in the business cycle. However, a lot of these insurance companies are then further reinsured with specific contractual limitations so that ideally the fund won't run out.

In the real world, the government can act as insurer of last resort and use tax dollars to with financing (though these usually are ideally set up with the initial fund).

[1]. https://www.investopedia.com/terms/c/catastrophebond.asp

Some risks are just uninsurable, even for countries. Large scale flooding and earthquake damage caused so much loss that no one can afford to pay for it. The US is lucky it can issue debt cheaply.

Why? So the sleazy insurance companies can deny or only pay a small percentage of your claim?? No thanks, the insurance industry has reduced itself to a rent seeking, regulatory capture machine with nearly zero value proposition for customers at this point.

Interesting startup in Earthquake insurance https://www.jumpstartrecovery.com

The earthquake was strong enough for a payout if you were located within the zone: https://twitter.com/yourjumpstart/status/1146850926512111616

Huh, we also just had a 5.8 magnitude one off the coast of BC, Canada [0] around 9:30 PM last night.

[0] http://www.earthquakescanada.nrcan.gc.ca/recent/2019/2019070...

There's a few articles that go into a loosely defined faulting area dubbed the Walker Lane[1][2][3] in which it's theorized that the East Pacific Rise (a rift), under the Gulf of California, may be expanding directly north. I know some geologists were surprised at first at the 7.4 Landers earthquake in 1994, and the article goes into that the Walker Lane seems to follow US 395, so I wonder if this is just a continuing extension of geologic activity associated with it.

[1] https://volcanohotspot.wordpress.com/2018/09/21/splitting-no...

[2] https://www.wired.com/story/walker-lane-move-over-san-andrea...

[3] http://www.bldgblog.com/2019/04/walker-lane/

That was fascinating. Thanks for those links.

I feel like we're woefully underprepared for earthquakes. It feels like pushing away technical debt on a societal scale.

I think the lack of damage from this shows a high degree of preparation. This same earthquake 50 years ago would have likely been much worse.

I was in Los Gatos for the epicenter of the 89 quake that was 6.7 I believe. It was pretty bad. It looks like this was handled much better.

6.7 is a lot stronger than a 6.4 though, as well.

If we are splitting hair, a 6.4 can technically be more dangerous compared to a 6.7 if the waves and the oscillation of the building coincide and amplify.

The Richter Scale is 10 x per full point. A 6.7 should be 4 times the strength of a 6.4

I was living in east bay during that time and just returned home from school. When the earthquake hit I could see the road create waves like a flipped rug. Fortunately no damage to our house.

Mind if I ask what part of Los Gatos you were in? I was near the corner of West Main and Bayview, a few blocks from downtown.

We didn't have much damage, but walking through the neighborhood afterward I counted about 20 houses that slid off their foundations.

This was also relatively remote. If it had been, say, the East Bay, where there’s high population density and lots of older homes with unreinforced masonry foundations, the situation would look a lot different.

Nah, there's just not a whole lot in that part of the world.

When I lived in that general area, there was a 7.1 or 7.2 and I think there was one death. IIRC, it was due to a heart attack and locals joked it was in reaction to the amount of liquor bottles broken in some liquor store because photos of the broken bottles got splashed all over the papers as one of the bigger points of damage.

A train was derailed in that quake and I think someone broke their arm but no one died because it was going unusually slow for a passenger train, having been scheduled behind a slow-moving freight train.

We had aftershocks for weeks that interfered with my sleep. Some of the aftershocks were above a 5.0.

There are so many building regulations, and grants to help older buildings meet standards that were not in place when they were built, awareness and education campaigns, and built-in procedures and policies in place that a regular California resident doesn't need to let the fear of an earthquake take over their life.

California is as prepared as any state can be for an earthquake and it is constantly looking for better ways to be prepared.

Well, not really. Compared to Japan...

Because Japan has way more earthquakes. Relatively, we are pretty well prepared in references to buildings. Now food supplies and power? I feel like people aren’t mentally prepared for that.

There's lots of regulations, but the regulations seem flawed by design. For example, in California at least, buildings need to be built to survive earthquakes, but not necessarily be functional.

https://www.latimes.com/local/lanow/la-me-ln-earthquake-legi...

In the event of a larger quake, you might survive the initial shock but a high percentage of your city, including new buildings will need to be torn down.

This represents a huge loss to a city in economic terms. Imagine if downtown LA lost 50% of its office buildings and apartment buildings. Compare this to Japan where buildings survive and are required to be usable. Japanese engineers are shocked at what they consider to be American substandard building codes.

The US govt has even concluded that better and stiffer building codes would save billions a year: https://cdn.ymaws.com/www.nibs.org/resource/resmgr/docs/MS_C...

Also a really relevant article with great info-graphics.

"Buildings Can Be Designed to Withstand Earthquakes. Why Doesn’t the U.S. Build More of Them?"

https://www.nytimes.com/interactive/2019/06/03/us/earthquake...

Here's a nice USGS predictive graph of earthquake 6.7+ probability for California from 10 years ago, posted on HN a few years ago: https://pubs.usgs.gov/fs/2008/3027/fs2008-3027.pdf

I didn’t feel it in West LA but my cat became extremely spooked. He was in an ultra hunting mode, flat to the ground and scanning the room. I never seen him act like this especially for this duration. He wouldn’t eat treats or respond to anything.

I wonder if it was just the vibration of the ground or if there’s some other factor alerting him.

I felt it pretty clearly in West LA. My dog decided to roll onto her back to get a massage out of the earthquake.

Got to love the difference between cats and dogs

Cats can probably feel or hear the p waves, which humans usually do not notice, and which travel faster than the more noticeable (to humans) s waves.

Here's a video of a bunch of cats in a cat cafe in Japan whose sleep is interrupted by an earthquake. They all wake up and start looking around about 9 seconds before the shaking starts, probably due to sensing the p wave. https://www.youtube.com/watch?v=VJ-p9qOhBv4

I'm pretty sure much of SF (marina, south beach, mid soma) are partially built on landfills are considered "liquification zones" by the city.

I think the term you're looking for is "liquefaction map" - I only know this term because we're exposed to the risk here in Charleston, S.C.: https://sf.curbed.com/2019/4/15/18311670/earthquake-map-cali...

That is scary to me. Should it be scary to me? In regards to liquefaction zones and earthquakes? I mean, i recently built a fence and the moisture in the ground made me conscientious of liquefaction when tamping for my gravel and posts, how does this play out for SF in an earthquake?

You're probably looking for the "Liquefaction Hazard Maps" page for the Bay Area: https://earthquake.usgs.gov/hazards/urban/sfbay/liquefaction...

Disclaimer: I am a geologist, but I'm not a P.G., hence all that I say on this topic is bullshit. p.s., Does your conference have beer? If it doesn't, I'm not going. I mean, I'll be so happy when AGU rolls around, because, man, I'm thirsty.

It should be scary. Soil liquefaction is one of the main failure modes of small structures in earthquakes. Take a look at the map for your area to know if it matters for you.

Parent used the correct term, a liquefecation map shows liquefecation zones.

It sounds like a big quake could solve the housing issues

You probably meant "land fill," not "landfills." Only a handful of things are actually built on landfills in the Bay Area, and all the neighborhoods you mentioned are built on fill. There are ships under Soma, though.

https://news.nationalgeographic.com/2017/05/map-ships-buried...

Luckily, this was far from population centers - epicenter about 10 miles from Ridgecrest, a town of 30,000 people just south of Naval Air Weapons Station China Lake, and just east of US 395, about 80 miles east of Bakersfield.

Informative USGS links include:

https://earthquake.usgs.gov/earthquakes/eventpage/ci38443183...

Select "View Neaby Seismicity" to see the 47+ recent quakes in this area.

It was pretty close to Trona. Having driven through Trona, life sucks in Trona and today it sucked a lot worse.

Lots of shaking here in the greater LA foothills, but no damage (though this house does have earthquake insurance).

Ah Trona. Not much out there to be honest. Here's what the view from Trona Pinnacles looks like: https://photos.app.goo.gl/LrML8TsBbZoW79t1A

Could be Mars

So it was apparently widely felt but Ridgecrest-China Lake, where it seems to have been felt the most, is not very close to the major populations. You can see this from cgoecknerwald's second link showing the locale of one of the major aftershocks.

[1] https://earthquake.usgs.gov/earthquakes/eventpage/ci38443095... to save slight scrolling

6.4 magnitude it is a lot. I hope there are no injured

Hope everyone is fine. Is it actually a good thing? I mean at least the prob of larger quake declines with it.

In 2010 there was a 7.2 centered 30 miles south of the socal border that caused $1B of damage on both sides.

https://en.m.wikipedia.org/wiki/2010_Baja_California_earthqu...

>Gallegos said that the dried chiles hanging from a hook on her kitchen wall were all shaking. "It was surreal."

was this really the best anecdote they could find to include in the story?

It happened 30 minutes before. I doubt the reporter had time to survey every person in a lesser-populated 500 square mile area.

I don't know, but anyway... If you happen to be under dried chiles when they shake, be sure to keep your eyes closed because the pain could make an earthquake much more pleasant. Been there done that, and that pain lasted hours... ouch!

On a more serious note, the anecdote might suggest that the earthquake produced very high frequency oscillations. Dried plants are relatively light and stiff so that a larger but slow displacement might be harder to spot by looking at them, but they could be much better at transmitting fast oscillations.

> Been there done that, and that pain lasted hours... ouch!

What an unusual form of earthquake injury!

Well, a fault was involved, although not a geological one:)

Read as: don't pick dried chiles directly from below, or at least close the damn eyes...

Oh, I see! I thought you meant that you'd actually experienced getting chili pepper in your eyes during an earthquake.

In the Loma Prieta earthquake Santa Cruz and Watsonville were badly damaged. But their was very little information getting out. So a lot of the coverage was San Francisco and Oakland. There is an inverse correlation between how bad a disaster is and a reporters ability to get any information.

The new early warning system did not trigger in L.A. Authorities said the projected damages wasnt big enough. The warning system is supposed to give seconds to tens of seconds of warning to turn off equipment and seek cover.

Not the submitter's fault, but I'm pretty sure the title is inaccurate

It's not. The last earthquake with a higher magnitude in California occurred in 2010. The title is just phrased wrong.

I saw a picture of a pinot that fell off a shelf and broke.

Try an entire liquor store: https://twitter.com/zomo_abd/status/1146843583988658176/vide...

This liquor store got pretty messed up: https://twitter.com/zomo_abd/status/1146843583988658176

edit: someone posted this a few seconds before me but i'll leave it up for posterity

We heard, but did not feel, this near Pacifica

Woke me up this morning, pretty wild

Lucky in middle nowhere

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