insaider 5 hours ago

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!

  • decimalenough 5 hours ago

    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.

    • throwaway894345 3 hours ago

      boarding the ferry may not be the most pleasant, however.

  • Polizeiposaune 3 hours ago

    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.

  • wiml 5 hours ago

    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.

    • lostlogin 4 hours ago

      Correct, but also, I’d bet there is a lurking tsunami expert here somewhere. Nothing is ever too niche for HN.

  • Grimburger 5 hours ago

    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.

  • bdickason 4 hours ago

    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.

  • seanmcdirmid 3 hours ago

    Lombok will have lots of higher ground at least. You really just have to be careful on and near the beach.

  • yxhuvud 3 hours ago

    Easily big enough, but how deep it was generated and how the movements happened do impact the risk a lot.

  • pestatije 5 hours ago

    the tsunami risk is negligible compared to the fire risk

    • insaider 2 hours ago

      Agreed, currently aboard and on high alert, pray for me HN

      • bdickason 36 minutes ago

        Let us know you made it ok!

  • rootsudo 4 hours ago

    Interesting times for the ferry indeed

CookieCrisp 6 hours ago

I know large earthquakes are effectively random (ignoring aftershocks) but this feels like a lot this year, yeah?

  • HaloZero 3 hours ago

    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)

    • astrobe_ 2 hours ago

      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.

      • dev1ycan an hour ago

        It's more likely related to planetary positions and or solar cycle/activity, "recent studies suggest a notable statistical correlation between specific solar magnetic milestones and the shifting phases of the El Niño-Southern Oscillation"

        Like in theory it doesn't make sense that el niño causes earthquakes, yet there seems to be more prominent ones during el niño however if both are related to sun cycle/activity it would make more sense (seeing how the moon affects earth as well)

  • keeda 2 hours ago

    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.

  • beloch 3 hours ago

    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.

    -------

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

  • jeffrwells 5 hours ago

    HN highlighting a lot this year, is all

  • kermatt 5 hours ago
    • LeBit 5 hours ago

      > 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.

      • jwilber 3 hours ago

        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.

    • goda90 5 hours ago

      Why does this page say there have been 0 >2.5mag earthquakes this year?

      • teraflop 4 hours ago

        Because this particular sensor network is only monitoring earthquakes in the Pacific Northwest of the USA, not worldwide.

  • jtfrench 3 hours ago

    It does feel like a lot

burnt-resistor 5 hours ago

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.

  • mikeyouse 5 hours ago

    Looks like it was a strike-slip fault, so a much lower tsunami risk compared to a subduction / dip-slip fault.