Alaska (pictured) is one of the areas that would be impact if the tsnuami hit (Getty Images)
A study warns of a potential 1,000-foot-tall "mega tsunami" that could devastate parts of America if a major earthquake hits the Cascadia subduction zone within the next 50 years.
Alaska, Hawaii, and the West Coast are most at risk due to the Cascadia subduction zone, a fault line stretching from Northern Vancouver Island to Cape Mendocino, California.
The Virginia Tech geoscientists' study estimates a 15 per cent chance of a magnitude 8.0 earthquake hitting the region in the next 50 years, potentially sinking coastal land by up to 6.5 feet and impacting cities like Seattle and Portland.
Mega-tsunamis, characterized by extreme wave heights, differ from ordinary tsunamis and climate-driven events because they would occur rapidly, "within minutes," leaving no time for adaptation.
The most severe effects are expected in southern Washington, northern Oregon, and northern California, with Alaska and Hawaii also vulnerable due to their seismic and volcanic profiles; the last major quake in the Cascadia subduction zone was in 1700.