Cascadia Mega-Quake Threat-- Even Larger than Previously Thought?

Japan’s Tohoku earthquake last year has provided valuable data that is altering scientists’ understanding of our local Cascadia earthquake potential. Geologists have documented some 22 megaquakes over the last 10,000 years - every 200 to 1,000 years, averaging some 500 years. The region’s last was on January 26, 1700.

This topic was explored last Sunday in Vancouver, BC in the “The Magnitude 9.0 Tohoku Earthquake and Tsunami: Significance for Japan and the World” symposium – part of the annual meeting of the American Association for the Advancement of Science.

Talks presented (see links for the abstracts) were:

• James Mori, Disaster Prevention Research Institute,
  Large Size and Large Slip of the 2011 Tohoku Earthquake
• John Anderson, University of Nevada; Hiroshi Kawase, Kyoto University
  Ground-Motion and Engineering Effects in the Tohoku Earthquake
• Kenji Satake, University of Tokyo
  Unforecasted Earthquake, Forgotten Tsunamis
• David W. Edgington, University of British Columbia
  Response and Recovery Following the Great East Japan Earthquake Disaster
• Stuart P. Nishenko, Pacific Gas and Electric Company
  Assessing Nuclear Seismic Safety and Reliability in the Post-Fukushima Era
• Kelin Wang, Geological Survey of Canada
  An Unsurprising Surprise

Researchers suggested that a Cascadia megaquake (geographically very similar to the Japanese site) could result in stronger shaking than previously expected along the coasts of Washington, Oregon and British Columbia.

Read a Seattle Times story on this at: http://seattletimes.nwsource.com/html/localnews/2017551958_sciencemeeting20m.html

[Update: also check out this blog on a recent NBCMS story on the same topic.]