[ogogmad]

Just learnt something from the article: It's interesting that the warping of the seafloor is what causes tsunamis, and not the shaking itself. It explains why a shoreline might sometimes recede away before a tsunami's crest strikes: The recession is caused by the seawater dropping with the seafloor, while the forward surge is caused by the ensuing bounce.

[pixl97]

Dropping or rising. At the borders of the sea and land plates the sea plates are slipping slowly below the continental crust. Pieces of the land crust get caught and dragged down. Over long periods of time you'll see forested land get dragged down below sea level and flooded to die.

The a rupture will occur, and in the biggest earthquakes you can get a fault that can rise 20 meters almost instantly causing trillions of tons of ocean to suddenly have to go somewhere. After the quake and tsunami you'll see the flooded forests can be many meters above land were new forest will grow and slowly start sinking again.

[MontagFTB]

The largest tsunami on record came from a landslide in a bay: https://en.wikipedia.org/wiki/1958_Lituya_Bay_earthquake_and...

[buildbot]

Yeah that'll happen when a good chunk of a mountain basically drops into your body of water, lol:

"The large mass of rock, acting as a monolith (thus resembling high-angle asteroid impact), struck with great force the sediments at bottom of Gilbert Inlet at the head of the bay. The impact created a large crater and displaced and folded recent and Tertiary deposits and sedimentary layers to an unknown depth."

With updated modeling showing that impact triggering the glacier to lift and subsequently release even more material, it's shocking anyone in the bay survived at all.

Edit - found a video with said papers modeling implemented, pretty neat: https://www.youtube.com/watch?v=B1axr5YGRwQ

[southernplaces7]

Much of the literature references this as the biggest ever tsunami at 500+ meters, but an account from one of the survivors who was there on his fishing boat (with his 7-year-old son!) said this specific thing:

"The wave definitely started in Gilbert Inlet, just before the end of the quake. It was not a wave at first. It was like an explosion, or a glacier sluff. The wave came out of the lower part, and looked like the smallest part of the whole thing. The wave did not go up 1,800 feet, the water splashed there."

Still insane, but it was the immediate splash that scoured away trees and soil cover up to 527 meters up the mountain face, not a proper tsunami.

Both the fisherman and his son survived btw.

[buildbot]

Yeah I personally agree it’s not quite the same as if the pacific ocean was coming up 527 meters before hitting the shore :)

[southernplaces7]

I'd absolutely love to see something like this live, in the flesh, obviously from far enough to survive it. It would be one of those spectacles for completely flabbergasting one's sense of importance in a self-remaking world.