- The possibility of a Great Aleutian Tsunami has emergency officials across the state of Hawaii redrawing inundation maps for the islands. Studying sediment deposits, Geophysicists at the University of Hawai‘i have identified a possible source region in Alaska’s Eastern Aleutian island arc, directly north of Hawai‘i, that has the potential for a very large magnitude 9 and over earthquake that could produce a mega-tsunami. Last week, the new extreme evacuation zones were unveiled on Oahu. The Big Island is currently working on its own updated maps. We spoke to Troy Scott with Hawaii County Civil Defense about the project.
GREAT ALEUTIAN TSUNAMI
- The images below are found in the report “Great Aleutian Tsunamis”. The report shows possible inundation from a GAT in Hilo (image below) far exceeds existing evacuation areas. Possible inundation in West Hawaii, on the other hand, does not appear to dramatically exceed existing tsunami evacuation areas.
Geophysicists at the University of Hawai‘i have identified a possible source region in the Eastern Aleutian (EA) island arc, directly north of Hawai‘i, that has the potential for a very large magnitude 9+ earthquake that could produce a Great Aleutian Tsunami (GAT). Based on geophysical research and subsequent computer modeling of inundation, new tsunami inundation maps have been produced to indicate the maximum extent of the GAT inundation. The GAT inundation maps have been used to determine a new Extended Tsunami Evacuation Zone (XTEZ). The XTEZ will serve as a second evacuation zone for only a GAT scenario, all other tsunami events will continue to use the existing updated 2010 tsunami evacuation maps. – U.H. Sea Grant Great Aleutian Tsunami and New Extreme Tsunami Evacuation Zones (XTEZ)