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The Aleutian Cradle of Tsunamis

Detailed Description


(Click here to read EOS Feature: Seismic Sources in the Aleutian Cradle of Tsunamis) 

New research on the Aleutian Islands has offered better insights into past great Alaska earthquakes and the dangerous, often far-travelling tsunamis they send across the Pacific.

  • Large & Frequent Aleutian Earthquakes: Between 1938 and 1965, nearly the entire 2,000-mile-long Alaska-Aleutian subduction zone ruptured in a sequence of powerful, tsunami-generating earthquakes.
  • Tsunami Impacts Around the Pacific: The unexpected consequences of great Aleutian earthquakes and Pacific tsunamis prompted the formation of the U.S. Tsunami Warning System.
  • Sleuthing Ancient Earthquakes - The Case of 1957 Quake: In 1957, a magnitude 8.6 earthquake ruptured roughly 750 miles of the Aleutian megathrust fault, generating a tsunami that threatened Hawaii. The geologic record tells of a long history of similar and even larger sized events.
  • Climate Change Exacerbating Tsunami Hazards: By 2100, sea level rise will increase the wave height of tsunamis generated by M8.0 earthquakes to heights similar to those produced by M9.1 quakes today. A magnitude 8.0 earthquake is 6.7 times more likely to occur than a magnitude 9.

Additional facts:

  • 4 - Number of 20th Century tsunami-inducing great Aleutian earthquakes
  • ~75yrs - Average time between  Aleutian tsunami-inducing earthquakes
  • ~750mi - Length of fault ruptured during 1957 earthquake
  • 6.7x - Increased likelihood of tsunami flood damage by 2100


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