Toomey, D.R., R.M. Allen, A.H. Barclay, S.W. Bell, P.D. Bromirski, R.L. Carlson, X. Chen, J.A . Collins, R.P. Dziak, B. Evers, D.W. Forsyth, P. Gerstoft, E.E.E. Hooft, D. Livelybrooks, J.A . Lodewyk, D.S. Luther, J.J. McGuire, S.Y. Schwartz, M. Tolstoy, A.M. Tréhu, M. Weirathmueller, and W.S.D. Wilcock (2014): The Cascadia Initiative: A sea change in seismological studies of subduction zones. Oceanography, 27(2), doi:10.5670/oceanog.2014.49, 138-150.
There is increasing scientific and public awareness that the Cascadia subduction zone, an active plate boundary fault off the coast of the Pacific Northwest (PNW), is capable of generating great earthquakes (magnitude 9 or larger). Concern over the earthquake hazard of this zone motivated creation of the Cascadia Initiative, an NSF sponsored community project to deploy and maintain an array of onshore/offshore seismic and geodetic sensors. PMEL scientists are co-investigators on the project and have led four oceanographic expeditions to collect data from the seafloor seismic components of the array. Details of the Cascadia Initiative experiment are highlighted in a paper published this week in the journall Oceanography.
The offshore seismic data will be used to study questions ranging from megathrust earthquakes, to volcanic arc structure, to the formation and deformation of the small oceanic plates that are being subducted beneath North America. Our society is not well prepared for a magnitude 9 earthquake if it were to occur along the PNW coast today. The US Federal Emergency Management Agency (FEMA) estimates that the direct financial losses would be $60 billion USD. The Cascadia Initiative project is laying a solid foundation for assessing, and thus ultimately helping to mitigate, the seismic and tsunamigenic hazards of a great earthquake in the PNW.