Pacific Northwest Workshop - 2012 Completed

March 21-22, 2012

South Campus Center, University of Washington, Seattle

Attendee List

Introduction & Overview

(Frankel, Petersen)

Cascadia Subduction Zone (CSZ)

• Recurrence rates and magnitudes of great earthquakes on the Recurrence rates and magnitudes of great earthquakes on the CSZ
  • Evidence from turbidites (submarine deposits) (Goldfinger)
  • Review of turbidite evidence (Atwater)
  • Evidence from onshore data (Nelson)
  • Possible temporal clustering of CSZ earthquakes (Wong, LaForge)
  • Approach used for Canadian national seismic hazard maps (Adams)
  • Effects of trial CSZ recurrence models on the hazard maps and review of November 2010 workshop on CSZ recurrence from turbidite evidence (Frankel)
• Models for the eastern edge of rupture zones of great Cascadia earthquakes
  • Review of various approaches (Hyndman)
  • Evidence from GPS and uplift data (McCaffrey, Schmidt)
  • Implications of Episodic Tremor and Slip to location of eastern edge (Houston)
  • Approach used for Canadian maps (Rogers)

• Review of December 2011 workshop on eastern edge of CSZ and evaluation of trial models (Frankel)

Crustal Fault Sources

• New findings on crustal faults (Sherrod)
  • Crustal deformation determined from GPS (McCaffrey)
  • Comparison of observed and predicted seismicity rates from crustal deformation (Hyndman)
  • New model linking eastern WA and western WA faults (Blakely)
  • Faults in western Washington (Kelsey)
  • Faults in eastern Washington (Sherrod)
  • Effects of including some of the proposed faults in the hazard maps (Moschetti)
  • Faults in Oregon (Madin)
  • Discussion of Quaternary Fault Database (Haller)
  • Approach used for Canadian maps (Rogers)

Deep Earthquakes

• Continuation of discussion on Cascadia subduction zone earthquakes
  • New information on deep, in-slab earthquakes. How to characterize hazard from deep earthquakes south of Puget Sound area? (Petersen, Moschetti)

Ground-Motion Prediction Equations

• Ground-motion prediction equations (GMPE's; also known as attenuation relations) used in the national seismic hazard maps (subduction-zone interface events, deep in-slab events, and crustal events)
  • Subduction-zone GMPE's used in BC Hydro hazard study (Abrahamson)
  • Latest results on subduction-zone GMPE's (Atkinson)
  • Effects of different subduction-zone GMPE's on seismic hazard maps (Petersen)
  • Plans for NGA (Next Generation Attenuation relations) for subduction-zone GMPE's (Bozorgnia)
  • What have we learned about ground shaking of great subduction-zone earthquakes from the recordings of the Tohoku, Japan, and Maule, Chile, earthquakes? (Stewart, Frankel, Atkinson)
  • Ground shaking from the Christchurch, New Zealand, earthquake; comparison with NGA for crustal earthquakes (Boore)

Engineering Issues

• Engineering needs and concerns in the Pacific Northwest. How can hazard assessment products be improved?
  • Earthquake engineering issues for the Pacific Northwest (Hooper)
  • Evaluation of effects of long-duration shaking from CSZ great earthquakes on building performance (Liel)
  • Design map procedures and USGS design-map products (Luco)
  • Long-period ground motions, 1-10 sec period (Crouse)
  • New downhole seismic array in Seattle to study liquefaction (Bodin)