Imaging the Plate Interface in the Cascadia Seismogenic Zone: New Constraints from Offshore Receiver Functions

Imaging the Plate Interface in the Cascadia Seismogenic Zone: New Constraints from Offshore Receiver Functions

The Cascadia subduction zone, where the Juan de Fuca (JdF) plate subducts beneath North America, has paleoseismic evidence ofMw ∼9:0 megathrust earthquakes (Nelson et al., 1995; Goldfinger et al., 2003). However, there are virtually no instrumentally recorded thrust-zone earthquakes, hence the location and behavior of the seismogenic zone is known only indirectly. Temperature has been proposed ...

Rotation and plate locking at the southern Cascadia subduction zone

Global Positioning System vectors and surface tilt rates are inverted simultaneously for the rotation of western Oregon and plate locking on the southern Cascadia subduction thrust fault. Plate locking appears to be largely offshore, consistent with earlier studies, and is sufficient to allow occasional great earthquakes inferred from geology. Clockwise rotation of most of Oregon about a nearby...

Scattered wave imaging of the oceanic plate in Cascadia

Fifty years after plate tectonic theory was developed, the defining mechanism of the plate is still widely debated. The relatively short, simple history of young ocean lithosphere makes it an ideal place to determine the property that defines a plate, yet the remoteness and harshness of the seafloor have made precise imaging challenging. We use S-to-P receiver functions to image discontinuities...

Offshore structure of the Cascadia subduction zone from full-wave ambient noise tomography

Hydrodynamic Simulations of Historic Tsunamis from the Cascadia Subduction Zone

INTRODUCTION We use new geological and hydrodynamic models to simulate the sea floor deformation and tsunami runup and inundation in Cannon Beach, Oregon (Fig. 1) produced by Cascadia subduction zone (CSZ) earthquakes. We then compare the simulated inundation with inland extent of buried sand sheets inferred to be of tsunami origin. The CSZ exhibits similarities to other subduction zones around...