Toward an integrative geological and geophysical view of Cascadia subduction zone earthquakes

Maureen A. L. Walton; Lydia M. Staisch; Tina Dura; Jessie K. Pearl; Brian L. Sherrod; Joan S. Gomberg; Simon E. Engelhart; Anne Trehu; Janet Watt; Jonathan P. Perkins; Robert C. Witter; Noel Bartlow; Chris Goldfinger; Harvey Kelsey; Ann Morey; Valerie J. Sahakian; Harold Tobin; Kelin Wang; Ray Wells; Erin A. Wirth

doi:10.1146/annurev-earth-071620-065605

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Toward an integrative geological and geophysical view of Cascadia subduction zone earthquakes

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Abstract

The Cascadia subduction zone (CSZ) is an exceptional geologic environment for recording evidence of land level changes, tsunamis, and ground motion that reveals at least 19 great megathrust earthquakes over the past 10 kyr. Such earthquakes are among the most impactful natural hazards on Earth, transcend national boundaries, and can have global impact. Reducing the societal impacts of future events in the U.S. Pacific Northwest and coastal British Columbia, Canada requires improved scientific understanding of megathrust earthquake rupture, recurrence, and corresponding hazards. Despite substantial knowledge gained from decades of research, large uncertainties remain about the characteristics and frequencies of past CSZ earthquakes. In this review, we summarize geological, geophysical, and instrumental evidence relevant to understanding megathrust earthquakes along the CSZ and associated uncertainties. We discuss how the evidence constrains various models of great megathrust earthquake recurrence in Cascadia and identify potential paths forward for the earthquake science community.

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Annual Review of Earth and Planetary Sciences Article

Source-reported bounding extent: 41.88592102814744° to 52.576349937498875° latitude; -134.05517578125° to -121.48681640624999° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Maureen A. L. Walton, Lydia M. Staisch, Tina Dura, Jessie K. Pearl, Brian L. Sherrod, Joan S. Gomberg, Simon E. Engelhart, Anne Trehu, Janet Watt, Jonathan P. Perkins, Robert C. Witter, Noel Bartlow, Chris Goldfinger, Harvey Kelsey, Ann Morey, Valerie J. Sahakian, Harold Tobin, Kelin Wang, Ray Wells, Erin A. Wirth. 2021. Toward an integrative geological and geophysical view of Cascadia subduction zone earthquakes. https://doi.org/10.1146/annurev-earth-071620-065605

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