Magnitude 7.4 Earthquake – 5 km S of San José del Palmar, Colombia | Hacker News Reader

Magnitude 7.4 Earthquake – 5 km S of San José del Palmar, Colombia

earthquake.usgs.gov

187 pointsBender72 comments

Was on the 6th floor of a tower. Shaking lasted almost 2 minutes. There was no damage as far as I could tell (Medellín) but they still evacuated everyone to inspect the building. City is in a bit of chaos, people are fine but unsettled, and the comms lines are clogged with people presumably calling their families.

Was a bit tense to see my phone alerts going off over and over, continually increasing the estimate of the earthquake strength, followed by the shaking getting worse.

For people who don't know, those phone alerts give you literally like 5 seconds of heads up. By the time I finished reading the first message, the shaking had already started. And I got the message while I was holding my phone and using it.

That's unavoidable. We now have shake alerts in CA but if the quake happens on the Hayward fault across the bay San Francisco isn't going to get much warning no matter what anyone does. By best estimates we may get 15s of warning.

15s is enough to book it to a close stairwell in some cases. I used to work in a dodgy building in the city. Any time one of those shake alerts hit, I would sprint to the stairwell and everyone would look at me funny. Jokes on them when the big one hits!

Depends. Surving means you have to deal with the aftermath. That's not going to be pretty.

I agree and I'm glad we have the alerts. I'm just saying we may not get any warning and that's nobody's fault.

I'm also thankful that we have at least some seismic standards and have continued to increase them.

Look at how a country like Chile fares where they don't just have standards they enforce them. You can't bribe your way out of proper seismic engineering for the most part. Then look at Columbia which technically has NSR-10 but enforcement is... not exactly stringent.

The results are obvious. Where standards are lax or just as importantly enforcement is lax structures collapse and people die. Where the standards are good and taken seriously damage is much less severe.

Even here in San Francisco things are not all perfect. Sometimes things slip through the cracks like the Millennium Tower. Others are known: the city has a special seismic hardened firefighting pipe network with big metal rods that clamp the pipes together to prevent joints from coming apart. With special seawater pumps and even ship-based seawater hookups so if all else fails they can pump vast volumes of seawater into that network... yet that network has absolutely massive gaps that have been known about for decades and still exist but there are no plans to expand it whatsoever. You'd think the city would continuously invest in this system to slowly expand it over time even if just a bit. But nope.

Need a rumble alert

Nice, 15s to move from underneath an unstable object or understand why the freeway is collapsing

The heads up is enough to read the message but not enough to decide if you need to act on it or not. Before you can process it the shaking starts.

You always need to act on it. Get an earthquake alert? Run outside. You can go back if it was a false alert.

In Mexico City the seismic alert gives like a minute (sensors are on the coast off Guerrero 350km away). Communities closer to the usual epicenter get almost no warning.

Before one can action one needs time to read and process whether the alert is for earthquake, tsunami, child abduction, etc

Those things could be solved with better UI (pictures, colors, ..) to see on one glance what is going on.

First word of the alert : EARTHQUAKE. What do you do?

There are no tsunamis in Mexico City haha

Well if there are then the world is really screwed.

I don't see the point of focusing the conversation on Mexico City. You may be far enough from the fault line to have plenty of time to react, but not everyone does (as you acknowledge). You may not have tsunamis, but that doesn't change the fact that one needs to know WHAT to react to.

You are welcome to think it is ridiculous for needing 5 seconds to process what alert is going off. But the simple reality is no good disaster plan should assume that everyone will immediately understand what is happening.

I wonder if that is enough to help actually. Better that you be holding your phone than a knife or a pot of water when the shaking starts. On the other hand you are startling those people.

The phone alerts sound quite dystopian and unsettling. As if the earth shaking and feeling of imminent doom wasn’t chaotic enough, now you have yet another element of annoyance and distress added to the mix as a cherry on top. Just enough of a distraction in a life/death situation to tilt the scales in a negative direction.

Knowing this, if you get the alert, get to safety immediately.

That alone can help save people.

5 seconds is still time purchased for those who use it wisely.

Google can detect major earthquakes about 15-30 seconds before visible shaking because of the huge network of accelerometers on Android phones worldwide. Those seconds can save lives if used properly.

It could help people react better too by confirming what they are feeling is an earthquake and not a train or plane or your neighbors. It could also wake someone seconds before so they are more aware when it happens and not awakening in primal panic mid quake.

It isn't a huge help, but broadcasting to everyone in range of certain towers shouldn't be dystopian.

They sound that way to be unique and attention-getting. They have to cut through the background noise of 21st century life.

Here's a (totally unsafe!) demo from the 80's of why sirens sound the way they do. Do not attempt at home.

https://www.youtube.com/watch?v=Lsfczwy3KOE

There are different sounds for different situations. I don't know the regulations (presumably they exist) that say when a particular sound should be used.

This fire alarm sounder has 32 possible sounds: https://www.youtube.com/watch?v=9os5EtDiVC4

The first is the default fire alarm noise in Britain, probably what I've heard most often.

I heard "LF Buzz" (2:32) in a nightclub, where it cut through the music. (I remember it as even more "yucky", maybe there were multiple sounders in the room.)

ha, i immediately think alert from a three letter company's on-call app. Now that's unsettling and straight fucking offensive!

Nah. Not really. I am used to phone alerts from Kyiv. When Putin and Klischko were making a pissing contest in the sky over Kyiv.

Here's what it sounds like on Android https://www.youtube.com/shorts/HQe8e3voRdw

IDK why it's so much more chill than the "child abduction" alerts I get. Those are straight up adrenaline-inducing so I've disabled them.

I regularly get "adult missing" alerts in Los Angeles, often with no more content than that. Absolutely useless. I can't think of any reason they send those out other than abject brain damaged incompetence or priming for some false flag.

> IDK why it's so much more chill than the "child abduction" alerts I get.

Japan, who had the first earthquake early warning system, did research and discovered that scary sounds made people panic, which is a bad thing in a situation when you need people to act quickly. Their standard alert sound is a fairly pleasant chime.

The downside is that some people now have panic reactions to the EEW sound, since it is standardized. I guess sometimes you can't win.

If you look up the sound, don't play it if you are in Japan. That's extremely no bueno.

This seems similar to the euphemism treadmill.

Some sounds are genetically more intense than others, like shrill screeching sorts of noises. So not quite as bad as the euphemism treadmill, because there is biology that makes certain sounds fundamentally less terrifying than others.

As someone living somewhere with a high chance of receiving a natural disaster warning I hate the AMBER alerts. How am I supposed to know if I need to evacuate immediately or just need to look for a car last seen three hundred miles away?

It's not even like the children's lives are in actual danger. Most of these alerts seem to be about custody disputes, in the vein of the kid went to his daddy's place for the weekend and hasn't been back by Monday 7am.

Checkout the Japanese ones for iPhone. I worked at a startup once and a tester was in a room with 30 phones and they all want off at once during a quake. The sound of the apocalypse right there.

Whenever I want to follow what's happening with a natural disaster like this, where many friends and family are potentially affected, I always use the Wikipedia page, which tends to have the most up-to-date information very quickly. It helps me avoid zooming in on the news and seeing rehashed articles posted on multiple websites.

https://en.wikipedia.org/wiki/2026_Colombia_earthquake

Didn't feel it but apparently it lasted several minutes and there was a lot of panic here in Bogota. Could see lots of people going out of their apartments in pijamas.

Also TIL that in 2023, while in a smaller earthquake webcam streamers (adult entretainers) went out of their apartments in lingerie.

Same here in Medellin. I can't imagine how it felt at San José

The national paper has a bunch of articles above the fold: https://www.eltiempo.com . 20+ confirmed dead in Pereira, a third-tier city with population of ~500,000. Many wounded.

Thankfully, it's a fairly deep (>100km) subduction zone earthquake. That means less immediate damage from ground acceleration than it could be from an earthquake of that size. However, a very large area may have seen significant liquefaction of soils in valleys and landslides on steep slopes. I'd wager we won't hear about most of the damage initially in the press.

I have family in this area in Valle del Cauca. We've heard from my immediate family and they're okay, but communication is spotty and we don't have a great sense of how bad things are yet. We fly into Matecaña International Airport in Pereira and it looks like the terminal had major damage and at least a few deaths. Shocking and horrifying stuff.

Really curious if it's related somehow to the Venezuela one. Interestingly, New Zealand also experienced a well above average frequency of shakes recently, although the scientist don't see any relation yet.

https://www.nzherald.co.nz/nz/successive-m5-plus-earthquakes...

My bed was shaking. I thought the guy in the other room had rough sex. Just realized when I got up, based on the warning message on my phone, that it was an earthquake.

I mean, it happens when you are half asleep. Later I realized that this would have been impossible with a prestressed concrete ceiling/floor.

Statistical anomaly detected: this morning I woke up from an earth quake in my dream. It was powerful enough to really sway the buildings and room I was in. Im in Texas though, but >= 7.0 earthquakes only happen a handful of times a year.

e: first time I dreamed of an earthquake

Magnitude 7.x earthquakes happen 1-2 times per month.

when was this? USGS shows no earthquake in Texas. Are you trying to say that Texas as >= 7.0 earthquakes a handful of times a year? According to wiki[0], Texas has never had anything close to a 7.0

[0]https://en.wikipedia.org/wiki/List_of_earthquakes_in_Texas

Sorry for the confusion, the earthquake was just in my dream. When I woke up there was not one

Unfortunately, USGS seismometers are not sensitive enough to capture intravisumal events.

once while visiting Peru, I had a vivid memorable dream that my cat was jumping on the bed. woke up to learn that I'd slept through an earthquake.

I hope in my lifetime we discover a way to predict earthquakes better, the danger to life from them would be significantly less if there was sufficient notification.

We can alert for storms, tornadoes, volcanoes, hurricanes, typhoons, and even somewhat extraterrestrial disasters like asteroids.

The earth itself must move in predictable patterns similar to the weather, and I'm sure there is decades of research around this I'll never even approach to understanding. Just surprising to have such a big knowledge gap that affects humanity year round

Even if it's predictable the opaqueness of the earth crust makes predictive models hard

Really I suspect that's the only hard part. If we had accurate 3d models of the structure (well 4d, 3d models over time) it would probably be reasonably easy to estimate how much strain it can take, and how much strain there is... Maybe not predict-to-the-second levels of detail but at least to predict that a quake we see is likely to be a precursor to a much larger one or is likely that peak.

But getting that data seems... practically impossible at our current tech level.

> at least to predict that a quake we see is likely to be a precursor to a much larger one or is likely that peak.

That we can basically do. "Observations show that the chance of an earthquake being followed by a larger one nearby and within a week is about 5%."

https://www.usgs.gov/faqs/what-probability-earthquake-a-fore...

It is an incredibly safe bet that any earthquake is not the sign of a larger one.

5% within a week is a very high set of odds for such rare events. Or to look at it from the other more relevant direction 70% of magnitude 7 or larger quakes have detected foreshocks...

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

I fear that we can only predict them if we deliberately trigger them to release the energy.

We are actually pretty good at predicting the long term for specific regions. This allows building codes to be based on the seismic activity of the region. Sadly this isn't something that's practical in many parts of the world

A few days ago, Egypt experienced its most violent earthquake in a long time. It occurred near the Suez Canal and lasted for about 30 seconds. It was absolutely terrifying.

In Bogotá I was asleep and a bunch of random alarms from other buildings woke me up. Didn't notice any shaking but the ceiling was making noises.

Lived it from my 20th floor apartment in Medellin. It was scary af, my wife started crying, but friends and family are OK.

Interesting tech fact: A friend of mine who lives in SF couldn't communicate with his parents who were in the countryside near Pereira (one of the 2 or 3 most devastated cities) because comms were pretty bad, but luckily they had Starlink to be able communicate.

Some technical background on the underlying siesmicity and causes can be found on the excellent Earthquake Insights blog

https://earthquakeinsights.substack.com/p/deadly-m74-earthqu...

Twitter has videos of people getting crushed (probably dead) by falling facade as they try to exit the building. I guess it's still considered smart to try to exit your building in a quake? Maybe it depends on the building.

Is this related to the one in Venezuela earlier this year?

This is the other side of the continent (Pacific Coast).

Doesn't mean it's not related.

Was pretty intense. Buildings and windows shaking.

venezuela and now this...

seems there is a lot of activity in south america

Venezuela and now this.... .

Is there something like a domino theory for earth quakes? Like first some stress releases in Venezuella, then the same stress travells further up the boundary, triggering a earth quake in a different region? Working its way up the plate boundary towards a big one like a fuse?

Yes, the seismic waves that are from one earthquake can absolutely give an extra oomph to a fault line that's somewhere else.

Colombia has been doing some rocking and rolling lately.

Colombia*

I read the title as 5 km S of San Jose (as in bay area) at first

Did you? Fascinating.

There's dozens of cities and towns named San José globally.

Some amusing data about this in the US:

There's at least one[a] town/city called San Jose in at least[b] 4 US states. Not to mention other things named such (e.g. 2 different San Jose creeks in California, neither of which is in the San Jose metro - one in LA and one in Monterey)

[a] there appears to be 2 towns in new mexico called San Jose

[a.2] Illinois amuses me because there's a San Jose and St Joseph both, and both are small.

[b] There appears to be a tiny (pop 15) town called San Jose in Texas, but it's unclear if that's officially incorporated, etc.

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