How Far Inland Can A Tsunami Travel On The East Coast USA?

REELDOC

REELDOC

The creek won't clear up til you get the pigs out.
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The War Wagon said:
Looks pretty innocuous at first (and NO - I'm NOT responsible for the Kitaro soundtrack 🤪 )

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I have talked with sailors--real sailors, men who spent their entire lives at sea--either US Navy, Merchant Marine, or commercial, about rogue waves and the like. Some mentioned being on 800-foot ships and seeing bows go up halfway up a wave before crashing down, waves coming down on superstructures that are 100 feet above the water. No, thank you.
 
If I Recall..... tsunamis are a result of two things: (1) Earthquakes and (2) Impacts.

Earthquakes on the sea floor can be devastating for sure. But, there is a limit to the height of the wave that it presents due to the movement of the crust can only transfer enough energy to make the sea rise 33 meters. The weight of the water makes it harder to transfer energy. While not near as high as the second cause... they cause more "ripples"/"waves" that just keep the water coming over a period of time.

Impacts are just what they say. Meteors, Comets, and more frequent Landslides and Huge Glacial Breaks can cause 1200 ft+ tsunamis. In 1958, a large earthquake (8+) caused a rock slide at Lituya Bay Alaska. The Wave washed trees away at the bay inlet at 1720 ft ASL after 90 Million Tons of Rock and Dirt slid into the water.

I want to say there was a show on NatGeo about this one. There was a fishing Trawler in the Bay and the guys said they were above the ridge lines when they crested the wave top. I'd say that was one heckuva ride.
 
VA_GENTLEMAN said:
If I Recall..... tsunamis are a result of two things: (1) Earthquakes and (2) Impacts.

Earthquakes on the sea floor can be devastating for sure. But, there is a limit to the height of the wave that it presents due to the movement of the crust can only transfer enough energy to make the sea rise 33 meters. The weight of the water makes it harder to transfer energy. While not near as high as the second cause... they cause more "ripples"/"waves" that just keep the water coming over a period of time.

Impacts are just what they say. Meteors, Comets, and more frequent Landslides and Huge Glacial Breaks can cause 1200 ft+ tsunamis. In 1958, a large earthquake (8+) caused a rock slide at Lituya Bay Alaska. The Wave washed trees away at the bay inlet at 1720 ft ASL after 90 Million Tons of Rock and Dirt slid into the water.

I want to say there was a show on NatGeo about this one. There was a fishing Trawler in the Bay and the guys said they were above the ridge lines when they crested the wave top. I'd say that was one heckuva ride.
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"SUMMARY AND CONCLUSIONS
A rockslide triggered either by movement on the Fairweather fault or the accompanying shaking, on July 9, 1958 plunged into Gilbert Inlet, causing water to surge over the opposite wall of the inlet to an altitude of about 1,740 feet and generating a gravity wave that moved out from the head of Lituya Bay at a speed of about 100 miles per hour."

 
That one was always interesting to me because I think the principle can be demonstrated in a swimming pool. If any of you have ever gotten in one of those big donut floats and started bouncing up and down. Eventually its like you hit the resonant frequency of the pool and the waves get much bigger as they bounce off each other and smack the side.

I think that wave was a one in a million chance that its amplitude matched the inlet shape and angle in such a way that it climbed that high. Amazing.
 
REELDOC said:
"SUMMARY AND CONCLUSIONS
A rockslide triggered either by movement on the Fairweather fault or the accompanying shaking, on July 9, 1958 plunged into Gilbert Inlet, causing water to surge over the opposite wall of the inlet to an altitude of about 1,740 feet and generating a gravity wave that moved out from the head of Lituya Bay at a speed of about 100 miles per hour."

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WOW..... I didn't think about the speed.....
 
Read up on Krakatoa explosion, impressive. Back in the 70's a bunch from our area quit their jobs and prepared for the end because a tidal wave was supposed to reach as far as Charlotte.
 
Blades said:
Fayetteville is mostly a swamp anyways, it won't take much to sink us. :(
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Yep, 90-100’ above sea level in most places. The river almost did us in during Florence, yet alone a tsunami.

VA_GENTLEMAN said:
If I Recall..... tsunamis are a result of two things: (1) Earthquakes and (2) Impacts.
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(3) A butterfly flaps it’s wings.
 
I used to see a tidal wave EVERY Thursday night on CBS when I was a kid. Watched it with my dad.

iu
 
As with all things in life, 'it depends'.....

Within an hour, tremendous tsunami waves inundated much of the eastern Japanese coast, sending 5- to 10-meter walls of water into coastal towns and cities. In Miyako, Iwate Prefecture, the runup height from the tsunami—the maximum elevation that water moved upland from the shore—reached 40.5 meters (133 feet) above sea level. Near Sendai, flood waters penetrated 10 kilometers (6 miles) inland.
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Ten Years After the Tsunami

One of the hardest hit coastal cities in Japan is still working to recover.
earthobservatory.nasa.gov earthobservatory.nasa.gov


I would think flooding from all the outflowing rivers would pose a serious threat much further inland than the direct impact of the tsunami itself as the rivers are pushed back upstream.
 
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How far depends on a few things.

How big was the displacement that produced the tsunami?

What is the underwater geography like where the tsunami approaches the coast?

What is the land geography where the tsunami makes landfall?
 
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