Numerical Simulation of M9 Megathrust Earthquakes in the Cascadia Subduction Zone

Assessing Margin‐Wide Rupture Behaviors Along the Cascadia Megathrust With 3‐D Dynamic Rupture Simulations

“…Kinematic rupture simulations are commonplace due to the straightforward relationship between fault slip and the recorded elastic displacement field once the Green's functions are known, allowing these types of models to be run at lower computational cost. Using the kinematic framework, potential locations of strong-ground motion sources along the fault, sedimentary basin amplification or tsunami generation have been assessed (Delorey et al, 2014;Frankel et al, 2018;Melgar et al, 2016;Olsen et al, 2008;Roten et al, 2019;Wirth et al, 2018 (Goldfinger et al, 2017) with corresponding estimated segment recurrence intervals in years. Primary morphotectonic regions identified by Watt and Brothers (2020) are superposed (blue dashed lines).…”

“…Kinematic rupture simulations are commonplace due to the straightforward relationship between fault slip and the recorded elastic displacement field once the Green's functions are known, allowing these types of models to be run at lower computational cost. Using the kinematic framework, potential locations of strong‐ground motion sources along the fault, sedimentary basin amplification or tsunami generation have been assessed (Delorey et al., 2014 ; Frankel et al., 2018 ; Melgar et al., 2016 ; Olsen et al., 2008 ; Roten et al., 2019 ; Wirth et al., 2018 , 2019 ; Wirth & Frankel, 2019 ). Most of these kinematic rupture models calibrate first‐order rupture parameters (slip, slip‐rate, rise‐time or rupture speed) from the few large megathrust earthquakes observed in other subduction zones (e.g., M8.2 2003 Tokachi‐Oki, M9.2 2004 Sumatra‐Andaman, M8.8 2010 Maule, M9.1 2011 Tohoku‐Oki).…”

Toward an Integrative Geological and Geophysical View of Cascadia Subduction Zone Earthquakes

“…Well-resolved preseismic, coseismic, and postseismic observations on other subduction zones provide a framework for interpreting geophysical and instrumental records in Cascadia. Many studies have modeled and interpreted activity in subduction zone earthquakes in the context of geologic structure (Davis et al, 1983;von Huene & Scholl, 1991;Saffer & Bekins, 2002;Lamb, 2006;Fujie et al, 2013;Cubas et al, 2013;McNeill & Henstock, 2014;Henstock et al, 2016;Bassett et al, 2016;Saillard et al, 2017;Tréhu et al, 2019;Olsen et al, 2020). Comparative studies can help to reconcile geophysical observations with the geologic record to best understand CSZ recurrence.…”

“…Furthermore, different rupture characteristics impact tsunami inundation, the extent of seismically triggered landslides, and the effects of geologic architecture on seismic wave amplification (Fig. 1;Geist, 2002;2005;Frankel, 2013;Frankel et al, 2018;Wirth et al, 2018;Roten et al, 2019;Wirth & Frankel, 2019). In this review, we summarize the substantial knowledge gained over decades of subduction zone research in Cascadia, discuss subduction zone processes that create geologic archives of past earthquakes, and identify associated uncertainties and natural variability.…”

Assessing Margin-Wide Rupture Behaviors along the Cascadia Megathrust with 3-D Dynamic Rupture Simulations

“…Using the kinematic framework, potential locations of strong-ground motion sources along the fault, sedimentary basin amplification or tsunami generation have been assessed (Olsen et al, 2008;Delorey et al, 2014;Wirth et al, 2018;Frankel et al, 2018;Melgar et al, 2016;Roten et al, 2019;Wirth et al, 2019 a, b). Most of these kinematic rupture models calibrate first-order rupture parameters (slip, slip-rate, rise-time or rupture speed) from the few large megathrust earthquakes observed in other subduction zones (e.g., M8.…”