A Mystery Tsunami Just Struck Japan; What Caused this Sudden Wave?

On September 24th (yesterday), a mysterious tsunami struck not only the Japanese mainland but also portions of the Izu and Bonin Islands. While this tsunami can be immediately traced to originating around the time of a magnitude 5.9 earthquake, this presents a problem. As, this quake was seemingly a full magnitudes too small to have been considered capable of producing a tsunami in the traditional sense. So, why did this tsunami occur, and was it related to the movement of magma at a volcano? This video will answer why this tsunami occurred, laying out the case that what occurred is not too uncommon of an event.

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Sources/Citations:
[1] Japanese Meteorological Agency
[7] U.S. Geological Survey

0:00 An Unexpected Tsunami
0:49 Tsunami Heights
2:10 Sumisujima
3:17 Trapdoor Faulting
4:25 Other Recent Tsunamis

[GeologyHub]

I want to add that two small tsunamis have also been generated by New Zealand’s Curtis Island volcano due to trapdoor faulting during the 21st century. Might be getting the dates wrong, but 2009 & 2017.

[alsecen]

Your grasp of the science is equalled by your gift for relaying the details to novice laymen. This is a fascinating channel. Thank you

[nortyfiner]

It's not the magnitude; it's the vertical displacement.

[quakekatut]

There are so many other factors. The USGS public lecture "Unusual sources of tsunamis" is a great lecture and discusses the MANY ways a tsunami can be generated.

[xwiick]

Thanks for all the hard work on these videos!

[digitaldreamer]

I am so glad my wife is back from her two week vacation in Japan with her childhood friend. They had two massive earthquakes and typhoon that forced them to spend three extra days there since all flights were cancelled. This all happened at the beginning of this month and it’s been quite a month for Japan also. 😮

[hereticpariah_]

Love this channel. First off, you most likely won't even hear about this event on the news. Second, the extra details wouldn't be mentioned. Third, the How it happened wouldn't even be Touched and even if it Was, unless the explanation came from a geologist it would likely be botched, confusing the viewer.
...love this channel.

[SK-gktx]

I love how much you know about volcanoes.

[alandpost]

Here I was assuming it would be an underwater landslide

[collette]

Very interesting and well explained 👍.

[jaymarlin]

Authentic and to the point. Superior report.

[beatricetreadwell]

So interesting! And so well explained! Thank you!😃

[chingachgook]

Nice explanation and graphics. Thanks!

[j]

🎉❤ fascinating. Thank you for the explanation.

[ThanksForTheLaugh]

So basically the caldera acts like a very large subwoofer, 20 minutes ago I didn’t know trapdoor earthquakes existed. Gotta love YT algorithm sometimes it is spot on.

[howieb]

Another excellent and informative video. Thank you and have a great day.

[raymondricci]

Great video. Good graphics, I learned a lot.

[Layla-yref]

Excellent report. I love your channel and the topics you cover. Thank you.

[dandomine]

I thought it would have been an underwater landslide? But I didn't know this was even a thing. Our planet is fascinating!

[paulmicks]

This was a great topic, shows how many dynamic mechanisms can be at play for one observed action.