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Comment by Hamuko | Hacker News Reader

Having listened to a short podcast about the predicted big earthquake that would hit California ("the Big One"), I'm not sure how people in California manage to get a good night's sleep.

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The New Yorker wrote about a similar issue for Oregon and Washington, in a 2015 article called “The Really Big One”. It would appear that the entire west coast of the United States is uninhabitable on a geologic timescale, and yet... here we are!

That's a bit like saying that Japan is uninhabitable because it experience devastating >9.0 earthquakes and accompanying tsunamis perhaps 1-2 times per millennia as seen most recently in 2011. Disasters happen but people rebuild, that's just the way it is. A full rupture of the Cascadia subduction[1] zone that that article[2] references would be devastating but would hardly end human occupation of the U.S. west coast.

[1]https://en.wikipedia.org/wiki/Cascadia_subduction_zone

[2]https://www.newyorker.com/magazine/2015/07/20/the-really-big...

That article was absolute garbage. They completely over-exaggerated things especially related to the waves considering seattle is in a bay. There's a reddit AMA thread with actual earthquake experts that debunks a lot of the exaggerations [0].

[0]: https://www.reddit.com/r/IAmA/comments/3da1mh/we_are_earthqu...

This article [0] makes the San Andreas big one seem relatively mild. California buildings are prepared for it and the fault is only capable of an 8.2 or so. Now Portland is overdue for a much worse quake...

[0] https://www.newyorker.com/magazine/2015/07/20/the-really-big...

There've been recent suggestions that older, post-1950 buildings, which generally used welded joints now known to be inadequate, may not fair well or may even fail catastrophically. Older steel buildings used riveted connections, while newer buildings use improved welding techniques and, at critical points, bolting. Riveting is more resilient, while bolting is considerably stronger.

Don't oversell rivets. They replaced the lattice trusses on the western span of the Bay Bridge with box beams and bolts, in part because of rivets. The cool thing with hot rivets is they contract as they cool, so they tighten well. The major downside is the steel isn't hardened--bolts are.

For a building on the drawing board today, there's no difference. The loads are the loads. Bolted, welded or riveted,the joints are designed to resist the same forces. Moderately recent buildings are the same. When an engineered system is stronger, less is used.

It is even worse than that. I read an article and had discussions with my civil engineer friend. Many of the different techniques used to "Earthquake" proof a building, especially tall towers, vary a lot and have NEVER had a real life test. On top of that, the regulatory oversight in insuring the ACTUAL construction was done properly based on the plan, is... not great. So hypothetically, if a 8.2+ Mag hit SF... we know many buildings like soft first floors, anything not on bedrock, etc, will fall, but even the towers.. it is all based on models. We really don't know what will and won't happen. As some famous (forgot name) architect in SF said back in the mid 1900's, "Don't build anything over 100ft in SF, just don't do it".

Earthquake risk comes up in discussions about reasons for not building taller. Meanwhile Tokyo has plenty of tall buildings and gets earthquakes all the time. I've never gotten a good explanation for this and don't know enough to judge if this is just another NIMBY excuse or legitimate.

It's not legit.

There's techniques to build tall in earthquake prone areas; such as building on rollers (New Zealand has some interesting examples of this approach), framing techniques, etc.

The notion that we have no real-world experience with how modern skyscrapers behave in earthquakes doesn't pass muster, for exactly the reason you pointed out. Not only is the scientific research easy to find on Google, but we can see videos of events on Youtube: https://www.youtube.com/watch?v=7Zw-BvKo0pI, https://www.youtube.com/watch?v=gglhWS23HfM

The notion that bedrock is a requirement is also easily refuted by a simple search of the scientific literature. TL;DR: it's complicated, obviously, but one potential advantage of friction piles and a floating foundation is less movement.

We don't need to be professional structural engineers to reject such simplistic, categorical notions; they're patently flawed.

I come from the New Madrid Fault area of the Mississippi River. California's faults are hilariously weak in comparison to what New Madrid does/did.

When one of California's faults can shift the entirety of the Mississippi River basin for a couple thousand miles, then I'll worry. Until then, you're probably better off worrying about the residents of Memphis, because if New Madrid happens to break out like it did in 1811, Memphis will sink into the aquifer upon which it was built. People like to joke about California 'falling into the water' with a big earthquake - Memphis is pretty much the only place in the country which has the actual chance of such an event happening due to its geographical location.

Wow, I’d never heard of the new Madrid fault, but FEMA said a recurrence if that earthquake series would cause thousands of fatalities! In California we’re aware of earthquakes since they happen with some regularity. Places like Oregon and apparently the Midwest scare me more, since they don’t have that low-level awareness (including building codes that take earthquakes into account).

If you're thinking of the maximum potential for a single quake event to impact human lives, the Newark Basin is high on the list due to its location. It's close to some of the highest concentrations of population in the nation, in an area of the continental plate that transmits seismic energy efficiently, and the vast majority of buildings nearby have zero earthquake resistance.

Earthquakes seem rare and relatively randomly distributed, so, as with New Madrid, the likelihood is definitely lower than it is in California. But the deep subsurface geology in the Basin is older, more complex, and less well understood than the plate boundary along the west coast. It's hard to rule out the possibility of a quake that would be big enough to have significant impacts on New York, Boston, etc.

I keep coming back to an observation that the places where civilization tends to exist are geologically and climatologically 'interesting'. If it's not one thing it's another.

I suppose so - if you ignore the whole continent of Europe.

Italy (Pompeii), Greece (Thera), and Iceland (Eyjafjallajokull) are all in Europe. Africa, most of Russia, and Northern Europe are volcano-free as they're not near fault lines (except the ones in the atlantic ocean and meditteranean sea)

> Africa, most of Russia, and Northern Europe are volcano-free as they're not near fault lines (except the ones in the atlantic ocean and meditteranean sea)

The East African Rift Zone is both an emerging plate boundary and a locus of volcanic and seismic activity.

Comment I read about Pompeii was the soil was really good because of Mount Vesuvius.

How soon we forget the Great Lisbon Earthquake.

North Sea flood of 1953 killed 2500 people.

I suppose there are some happy places unaffected by earthquakes, volcano's, floods, extreme weather. I'm dubious we can all move there.

Italy is pretty interesting geologically, Greece is not bad, Istanbul is amazing.

There are plenty of places without any particular natural risks, e.g., New York City and London, both of which standard and dull four-seasons temperate climates and dead geology.

There was significant flooding in NYC just a few years ago due to Hurricane Sandy.

A large part of London is built on floodplain though, hence the need for the enormous Thames barrier (https://en.wikipedia.org/wiki/Thames_Barrier). Flooding is a pretty big natural risk here.

> There are plenty of places without any particular natural risks, e.g., New York City

I suspect New York City has more deaths per capita over time from the combination of natural environment events (earthquakes, weather, etc.) than California.

It's certainly not free of natural risks.

NYC earthquake risk is on-par with the Bay Area because while the magnitude of the quakes would be lower, the bedrocks transmits the energy better, the buildings are under-engineered for earthquakes, and it has a higher population density.

NYC is not close to any major geological activity. The east coast, unlike the west coast, has been quiet for, what, 60 million years? The Appalachian mountains are worn-down nubs. The closest seismic zones are, what, the Caribbean and the New Madrid area of Missouri, IIRC.

Depending on how you define “major” (I just saw a Twitter status arguing that San Francisco does not get “truly big” earthquakes because it’s a transform boundary and not a subduction zone), New York has a bunch of faults and does get significant geological activity. https://twitter.com/typesfast/status/1183984933733158913 https://nypost.com/2017/09/09/new-york-city-is-overdue-for-a...

Living in Ontario the only thing I'm worried about is minor flooding, nothing on the scale that you see on the coasts. Storms (Nothing like in the US), Snow, Rain, Sun. No real major catastrophes possible.

I'll point out that weather related deaths in Ontario are higher than earthquake related deaths in California.

Blizzards (including Nor'easters) are a valid, natural danger for NYC and the rest of the Northeastern U.S.

Part of it is we like building on water. Part of it is that a lot of the world has interesting natural disasters.

How can you manage to get a good night's sleep knowing you'll eventually die, with 100% certainty?

With California, it's even easier - while dying is pretty much guaranteed, The Big One may be hundreds of years in the future.

Yeah you might get lucky and something else kills you first!

The experts have been talking about the big one for decades. I think most people are becoming desensitized to the phrase.

Easy: you don't fret over low probability events that are unlikely to cause you major damage anyway. (I've lived through multiple major earthquakes! meh, what's one more.)

People are resilient. Earthquakes are nothing compared to repeated terrorist attacks experienced by people in places in Israel and Palestine, but yet the endure:

https://www.economist.com/international/2016/09/03/learning-...

Many people are resilient, but your reply lacks nuance.

Some people are completely incapacitated (e.g. PTSD, Agoraphobia, etcetera) by the various effects of an earthquake (destruction, death, loss of home or job, other hardships). Many more have lower-level permanently ongoing problems that affect their work or life.

Source: friends and acquantances after Christchurch 2011 earthquake.

Edit: startups can be hit particularly hard since they are fragile and a big external event can wipe them out.

Funny enough, we just had a small earthquake a few minutes ago here in Los Angeles. And yes, it woke up my wife (but not the kids).

Even a REALLY big earthquake is probably not going to knock down my house... we will likely be ok. Have the emergency kits ready.

Have an earthquake kit handy, buy earthquake bonds, and sleep tight.

TL;DR one gallon of water per person per day, expect a boil-water order for one month and disruption of telco and transit for a bit, so keep a stash of cash on hand. Stay put for the immediate time after the foreshock and aftershocks. Not much else you can do.

TL;DR go look at a real earthquake kit guide.

"the big one" isn't expected to cause significant damage to the area in which I live, so there you go.

There's a non-zero probability that you'll tunnel through the floor and get buried under dirt - quantum mechanics 101.

How do you manage to sleep now?

I would assume the probability of that is roughly comparable to the probability of a Boltzmann brain[1] assembling, which is roughly one in 10^10^50, or 10 with 10^50 zeros after it. Could be as high as 1 in 10^10^30 based on a discussion of the probability of macroscopic tunneling that I read. Assuming you wrote this number down in decimal form using the most efficient available technology[2], it would require the material in roughly 400,000 galaxies the size of the milky way.

Regarding earthquakes, the USGS estimates[3] the probability of a magnitude 7.5 quake near LA is about 30% in the next 30 years. A magnitude 8 is probably 150 times less likely, so the probability might be roughly 1/15,000 to happen this year.

The difference between 1/15,000 and 1/10^10^40 is...roughly 10^10^40 times. So if you worry about tunneling through the floor, then a devastating earth quake is essentially as likely as not tunneling through the floor.

Really, have a sense of proportion!

[1]https://en.wikipedia.org/wiki/Boltzmann_brain

[2]https://en.wikipedia.org/wiki/IBM_(atoms)

[3]https://www.usgs.gov/faqs/what-probability-earthquake-will-o...

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