Oceanography The Official Magazine of
The Oceanography Society
Volume 27 Issue 02

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Volume 27, No. 2
Pages 138 - 150

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The Cascadia Initiative: A Sea Change In Seismological Studies of Subduction Zones

By Douglas R. Toomey , Richard M. Allen, Andrew H. Barclay , Samuel W. Bell , Peter D. Bromirski , Richard L. Carlson , Xiaowei Chen, John A. Collins , Robert P. Dziak , Brent Evers, Donald W. Forsyth, Peter Gerstoft, Emilie E.E. Hooft , Dean Livelybrooks, Jessica A. Lodewyk , Douglas S. Luther , Jeffrey J. McGuire, Susan Y. Schwartz , Maya Tolstoy , Anne M. Tréhu, Michelle Weirathmueller , and William S.D. Wilcock 
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Article Abstract

Increasing public awareness that the Cascadia subduction zone in the Pacific Northwest is capable of great earthquakes (magnitude 9 and greater) motivates the Cascadia Initiative, an ambitious onshore/offshore seismic and geodetic experiment that takes advantage of an amphibious array to study questions ranging from megathrust earthquakes, to volcanic arc structure, to the formation, deformation and hydration of the Juan De Fuca and Gorda Plates. Here, we provide an overview of the Cascadia Initiative, including its primary science objectives, its experimental design and implementation, and a preview of how the resulting data are being used by a diverse and growing scientific community. The Cascadia Initiative also exemplifies how new technology and community-based experiments are opening up frontiers for marine science. The new technology—shielded ocean bottom seismometers—is allowing more routine investigation of the source zone of megathrust earthquakes, which almost exclusively lies offshore and in shallow water. The Cascadia Initiative offers opportunities and accompanying challenges to a rapidly expanding community of those who use ocean bottom seismic data.

Citation

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):138–150, https://doi.org/10.5670/oceanog.2014.49.

Supplementary Materials

> Science Objectives of the Cascadia Initiative (77 KB pdf)

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