Scientists had considered the eastern section of the Aleutian Islands unlikely to generate earthquakes but new research shows it could be a future source of quakes and tsunamis large enough to hit Hawaii.
U.S. Geological Survey scientists compiled research on the 125-mile section of the Alaskan islands.
Field work from an island near Dutch Harbor revealed “sand sheets”, defined as deposits of sand, were lifted off beaches sometime in the past and ended up a half-mile inland.
Geologist Robb Witt says that evidence means large tsunamis have hit Sedanka (zeh-DONK-ah) Island frequently. However, “frequently in geologic terms means about every 300 to 340 years.
It was previously thought by scientists that section of the Aleutians was positioned on a so-called “creeping” fault, meaning the earth’s tectonic plates move continuously without building the strain that leads to earthquakes.
Witt says Hawaiian officials have been notified of the new information and have used the USGS study to broaden tsunami evacuation zones.
