Is this big enough to produce a Tsunami? Apparently maybe only a small localised one, but I'm supposed to be getting the ferry from Lombok to Bali shortly and two of those have already burnt down the last 2 weeks!
A ferry in the open ocean is one of the safer places to be during a tsunami. Remember, it's not a surf-style wave, but a gradual increase in water level.
They've declared the event over - some waves were generated but nothing particularly large. Bulletin 3 for the recent quake includes wave height observations - maximum reported was 94cm; most were under 50cm.
I've seen "possible tsunami" pre-warnings, and a sea level gauge at/near Lembar showing sea level oscillations - so I would recommend keeping a close watch on some information source that's better than HN comment threads, yes.
I would upgrade the ferry and make sure to get a high quality one given all the swell in the ocean already (most of bali had 6ft+ waves yesterday) and this incident. Not worth the risk.
According to long-term records (since about 1900), we expect about 16 major earthquakes in any given year. That includes 15 earthquakes in the magnitude 7 range and one earthquake magnitude 8.0 or greater. In the past 40-50 years, our records show that we have exceeded the long-term average number of major earthquakes about a dozen times.
I've always wondered if the melting of glaciers would move masses from one place to another and induce some tectonic moves. But the mass is most likely not significant enough; water/ice has a relatively low density after all.
Sure feels like it in my corner of the Bay Area, since we had a prolonged earthquake swarm earlier this year, even hitting a record number of earthquakes per day or something like that.
Earthquakes can occur in swarms[1] (distinct from aftershocks), with many of a similar size (i.e. Not a big quake followed by smaller ones) occurring in a small area over "relatively short" periods of time (i.e. days, weeks, or years).
The USGS map shows the 7.7 quake being followed by about 19 other smaller quakes near or in Indonesia within just a few hours. These are probably aftershocks.
> Note: While it may look like there have been an increase in total number of earthquakes since about 2020, this is actually due to the increasing number of seismic stations installed in the park since 2020 that are able to detect smaller (<= 0.5 magnitude) earthquakes. If you look at the number of earthquakes >= 1.0, the rate has remained about the same.
Somehow I don’t think people are confusing raw seismic station earthquake counts with the three back-to-back high profile/magnitude earthquakes that recently occurred in Venezuela, Colombia, and Indonesia.
I understand the point, maybe those recent earthquakes aren’t ood, but still.
Beachball (moment tensor) says it's a thrust fault with a ton of lateral movement (aka attempted subduction.) https://earthquake.usgs.gov/earthquakes/eventpage/us6000tkt2... eyeballs filled in are pretty much thrust faults and horizontal like that means subduction-possible movement.
Is this big enough to produce a Tsunami? Apparently maybe only a small localised one, but I'm supposed to be getting the ferry from Lombok to Bali shortly and two of those have already burnt down the last 2 weeks!
A ferry in the open ocean is one of the safer places to be during a tsunami. Remember, it's not a surf-style wave, but a gradual increase in water level.
boarding the ferry may not be the most pleasant, however.
Indonesia's tsunami bulletins appear to be here:
https://rtsp.bmkg.go.id/publicbull.php
They've declared the event over - some waves were generated but nothing particularly large. Bulletin 3 for the recent quake includes wave height observations - maximum reported was 94cm; most were under 50cm.
I've seen "possible tsunami" pre-warnings, and a sea level gauge at/near Lembar showing sea level oscillations - so I would recommend keeping a close watch on some information source that's better than HN comment threads, yes.
Correct, but also, I’d bet there is a lurking tsunami expert here somewhere. Nothing is ever too niche for HN.
I would upgrade the ferry and make sure to get a high quality one given all the swell in the ocean already (most of bali had 6ft+ waves yesterday) and this incident. Not worth the risk.
Tsunamis are only an issue close to shore. In the ocean it's barely a mild wave.
In a boat going further out is the safest thing you can do if there's a tsunami warning.
Safer than going inland..?
There have been 70m tsunamis and lakes get tsunamis too, so… maybe?
https://en.wikipedia.org/wiki/List_of_tsunamis
Lombok will have lots of higher ground at least. You really just have to be careful on and near the beach.
Easily big enough, but how deep it was generated and how the movements happened do impact the risk a lot.
Safe travels, friend.
the tsunami risk is negligible compared to the fire risk
Agreed, currently aboard and on high alert, pray for me HN
Interesting times for the ferry indeed
I know large earthquakes are effectively random (ignoring aftershocks) but this feels like a lot this year, yeah?
Yeah, I looked this up and USGS literally has a page about this.
https://www.usgs.gov/faqs/why-are-we-having-so-many-or-so-fe...
According to long-term records (since about 1900), we expect about 16 major earthquakes in any given year. That includes 15 earthquakes in the magnitude 7 range and one earthquake magnitude 8.0 or greater. In the past 40-50 years, our records show that we have exceeded the long-term average number of major earthquakes about a dozen times.
You can see a map of ALL the 7+ here:
https://earthquake.usgs.gov/earthquakes/map/?extent=-89.0318...
The search filtering is a bit hard to find in the UI but the parameters in the URL can be modified. (We had 16+ 7.0 last year as a comparison)
I've always wondered if the melting of glaciers would move masses from one place to another and induce some tectonic moves. But the mass is most likely not significant enough; water/ice has a relatively low density after all.
Yea, feel like a lot of big ones this year, but looking it up https://en.wikipedia.org/wiki/List_of_earthquakes_in_2026 it is actually not necessarily worse than previous years.
Given we are barely beyond half of the year, that puts us close to the outlier that was 2023 in the 7+ range.
2023 also had a strong el-niño event.
Sure feels like it in my corner of the Bay Area, since we had a prolonged earthquake swarm earlier this year, even hitting a record number of earthquakes per day or something like that.
76 quakes ranking 7.0+ so far this decade, including 10 this year.
https://en.wikipedia.org/wiki/List_of_earthquakes_2021%E2%80...
Earthquakes can occur in swarms[1] (distinct from aftershocks), with many of a similar size (i.e. Not a big quake followed by smaller ones) occurring in a small area over "relatively short" periods of time (i.e. days, weeks, or years).
The USGS map shows the 7.7 quake being followed by about 19 other smaller quakes near or in Indonesia within just a few hours. These are probably aftershocks.
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[1]https://en.wikipedia.org/wiki/Earthquake_swarm
HN highlighting a lot this year, is all
It does feel like a lot
I was wondering the same: https://www.morageology.com/earthquake_year.php
> Note: While it may look like there have been an increase in total number of earthquakes since about 2020, this is actually due to the increasing number of seismic stations installed in the park since 2020 that are able to detect smaller (<= 0.5 magnitude) earthquakes. If you look at the number of earthquakes >= 1.0, the rate has remained about the same.
Somehow I don’t think people are confusing raw seismic station earthquake counts with the three back-to-back high profile/magnitude earthquakes that recently occurred in Venezuela, Colombia, and Indonesia.
I understand the point, maybe those recent earthquakes aren’t ood, but still.
Why does this page say there have been 0 >2.5mag earthquakes this year?
Because this particular sensor network is only monitoring earthquakes in the Pacific Northwest of the USA, not worldwide.
So Google Earth says the ocean depth at the epicenter is 6,286 ft / 1,916 m, but I couldn't find a corresponding tsunami alert or evaluation of risk.
Looks like it was a strike-slip fault, so a much lower tsunami risk compared to a subduction / dip-slip fault.
Beachball (moment tensor) says it's a thrust fault with a ton of lateral movement (aka attempted subduction.) https://earthquake.usgs.gov/earthquakes/eventpage/us6000tkt2... eyeballs filled in are pretty much thrust faults and horizontal like that means subduction-possible movement.
What is the moment tensor in this context?