GeologyHub video about this earthquake and "megaquake warning" that followed: https://www.youtube.com/watch?v=1POo07B2Iko
Strong earthquake hits northern Japan, tsunami warning issued
141–150 of 168 posts
Re: Strong earthquake hits northern Japan, tsunami warning issued
#142Earlier quoted context omitted.
When I moved to SF, someone told me that the three most important things you can do for earthquake safety are: - make sure nothing can fall on you when you're in bed (no mounted artwork above the headboard; no lamps etc on side tables that are high enough to fall on you) - make sure you have footwear in your bedroom, so you can be mobile if there's broken glass everywhere - store extra drinking water somewhere (I use…
Keep in mind that this is a major metropolitan area in a state that has a history of earthquakes. You can expect state level response (and federal as well) within the same day. Their main priority will be water, and elements exposure. Guidance varies. California list here https://earthquake.ca.gov/wp-content/uploads/sites/8/2025/02... You should have water, food, medical supplies, and cash. btw you might find this in…
Sf fire department has also a pdf with what you should have in an at home emergency kit. It's some simple things you can get in one trip to a camping store and Walgreens. https://sf-fire.org/media/794/download?inline
I also recommend SF people consider joining NERT: neighborhood emergency response team. Disaster after disaster should teach us the opposite of what you argue in terms of response: in fact it's more likely that the scale of people affected will quickly overwhelm resources, and the existence of choke points will severely limit movement of people and resources, especially if infrastructure is damaged and people are flooding out of the city. That can be mitigated by having locals trained to help facilitate emergency response efforts. It's less "pulling people out from under bookshelves" and more "help managing the bureaucracy of the fire department," forms on forms on forms! Though the training does involve pulling someone out from under a bookshelf. It's a week long and quite fun!
Re: Strong earthquake hits northern Japan, tsunami warning issued
#143Earlier quoted context omitted.
I think you intended this to be a validation of the idea that small quakes relieve stress and therefore lower the chance of a large quake. The above link does not answer that question. It is relating stress release to "fault strength", or the maximum shear stress that can be withstood by the fault. There is an incidental relationship with depth that plays a role. The video linked nearby (on criticality) also does not…
EQs are a release of energy. That energy is stored as stress prior to release. There is a finite amount of stored energy at any given time. So the statement "EQs release stress" is true and it follows that adding the modifier "small" to the front doesn't change this. It should also be immediately apparent that it would be very surprising if there were not statistical implications as a result of this. So surprising in…
This part is unquestionably true. But since we don't have a direct measurement of the stored energy at a given time, the occurrence of an earthquake acts as both an indicator of release of stored energy but also, potentially, evidence of increasing stored energy.
Like how buying a Porsche costs money, and leaves you poorer than before you bought it, but when you see stranger buy a Porsche, you update towards believing that they're wealthy rather than poor.
Disclaimer: I am not a geoscientist.
Re: Strong earthquake hits northern Japan, tsunami warning issued
#144Earlier quoted context omitted.
Good luck, the Sapporo Chitose airport is closed for inspection of both runways. BTW, you are safer in hotel than outside. No need to stay in lobby, go to bed, just protect your head. I experienced much bigger one in Sapporo in 2018.
I’m curious, how is it more safer inside a building than being outside?
Sure, in the middle of a magnitude 9 earthquake I'd rather be in the middle of a suburban golf course (as long as it is far from any coastal tsunami) than any building, but I don't spend the majority of my time outside.
Two issues: 1. If you're making this choice during an earthquake, "outside" is often not a grassy field but rather the fall zone for debris from whatever building you're exiting. 2. If the earthquake is big/strong enough that you're in any real danger of building level issues, the shaking will be strong enough that if you try to run for the outside you're very likely to just fall and injure yourself.
Re: Strong earthquake hits northern Japan, tsunami warning issued
#145Earlier quoted context omitted.
You are certainly reading something into my question that isn't there. I'm genuinely ignorant. I thought you were saying that predictions of a strong aftershock following an M8.8 were dumb, but the same thing following an M7.6 were smart. Is that not the case? Again, sorry if this seemed antagonistic or something, I really am just unsure of what you were saying.
A manga book published in 1999 randomly predicted a disaster in March 2011, which seemed to come true with Fukushima. The manga was re-published in 2021 predicting a M8.8 in July 2025, but nothing happened. This is the dumb prophecy part, it was not based on seismology studies, just a shot in the dark to try to seem prophetic again. Countless works of fiction are published every year which predict some future disaste…
Math nazi in me really wants to point out that an event with a 1:1000 probability would be expected to be seen (> 50% probability) in about 700 years, not 1000.
Re: Strong earthquake hits northern Japan, tsunami warning issued
#146Earlier quoted context omitted.
A manga book published in 1999 randomly predicted a disaster in March 2011, which seemed to come true with Fukushima. The manga was re-published in 2021 predicting a M8.8 in July 2025, but nothing happened. This is the dumb prophecy part, it was not based on seismology studies, just a shot in the dark to try to seem prophetic again. Countless works of fiction are published every year which predict some future disaste…
Math nazi in me really wants to point out that an event with a 1:1000 probability would be expected to be seen (> 50% probability) in about 700 years, not 1000.
Roughly how many Paul Erdős's to every Oswald Teichmüller though?
Re: Strong earthquake hits northern Japan, tsunami warning issued
#147Earlier quoted context omitted.
Math nazi in me really wants to point out that an event with a 1:1000 probability would be expected to be seen (> 50% probability) in about 700 years, not 1000.
Roughly how many Paul Erdős's to every Oswald Teichmüller though?
Re: Strong earthquake hits northern Japan, tsunami warning issued
#148Earlier quoted context omitted.
EQs are a release of energy. That energy is stored as stress prior to release. There is a finite amount of stored energy at any given time. So the statement "EQs release stress" is true and it follows that adding the modifier "small" to the front doesn't change this. It should also be immediately apparent that it would be very surprising if there were not statistical implications as a result of this. So surprising in…
This part is unquestionably true. But since we don't have a direct measurement of the stored energy at a given time, the occurrence of an earthquake acts as both an indicator of release of stored energy but also, potentially, evidence of increasing stored energy. Like how buying a Porsche costs money, and leaves you poorer than before you bought it, but when you see stranger buy a Porsche, you update towards believin…
Fair enough. I'm also not a geoscientist, and to clarify I didn't mean to imply any specific statistical effect there. It seems entirely reasonable to me that a series of EQs might tend to increase in intensity.
In reality I think (layman's impression) that there's rough (post hoc) evidence for both things. Foreshocks followed by noticably larger EQs as well as trains of progressively smaller EQs.
Re: Strong earthquake hits northern Japan, tsunami warning issued
#149Was in a hotel in Sapporo, almost got thrown out of bed. Lot of people in the hotel lobby now. Considering leaving Hokkaido by air if a Hokkaido and Sanriku Subsequent Earthquake Advisory is issued, don't really want to be in a potential megaquake.
People were freaking about the July megaquake prophecy and nothing happened. Trying to time it is silly, just chill and enjoy your stay, you'll probably be fine.
Megaquake is following a major earthquake is well documented. This is not silly prophercy stuff. Parent was talking about that case.
Re: Strong earthquake hits northern Japan, tsunami warning issued
#150Earlier quoted context omitted.
Good luck, the Sapporo Chitose airport is closed for inspection of both runways. BTW, you are safer in hotel than outside. No need to stay in lobby, go to bed, just protect your head. I experienced much bigger one in Sapporo in 2018.
I’m curious, how is it more safer inside a building than being outside?
The main two ways people get injured in earthquakes (at least in Japan) are a) gas fires b) things falling on them. And being outside but near buildings is a good way for things to fall off those buildings onto you.