Thread: tsunami speed please explain

Originally Posted by Glider

Terra firma? First find a continent and then live in the middle.

mick

Yep. The more firmer, the less terror.

Originally Posted by Tonyz

Tonga place I dearly love has had big earthQ as you know and Tsunami....

now looking at distances NZ has tidal damage early this morning, parts of California also, but dear old Aus what did we get.
The force of that eruption is blind crazy, felt and heard in FIJI, heard in Alaska? what I guess sound travelling over water nothing stopping it except big waves.

With regard to the sound being heard thousands of kms away in alaska... It's been a few decades since learning this but the sound waves (evergy waves) tends to go up and out, less land hugging, and then bounce off the stratosphere and are redirected back to earth where the waves collide with some distant ears... Often times those that are medium distance don't hear the blast as it travels way over their heads.


Wave speed has all to do with the pressure wave that they originate from. Apparently tidal waves have been measured at up to 700km/hr (my guess is 700km/hr is close to the maximum velocity of an energy wave in water). Those sorts of speeds would only originate with convergent plate earthquakes (or astreroid impact). And only if the land slip moved at 700km/hr. If the land slip moved at 400km/hr then the wave couldn't exceed 400km/hr. I don't think a volcanic eruption (explosive release) has the energy to send a radiating wave out at such speeds. the energy dynamics are way different.