Reflection signature of seismic and aseismic slip on the northern Cascadia subduction interface

@article{Nedimovi2003ReflectionSO,
  title={Reflection signature of seismic and aseismic slip on the northern Cascadia subduction interface},
  author={Mladen R. Nedimovi{\'c} and Roy D. Hyndman and Kumar Ramachandran and George D. Spence},
  journal={Nature},
  year={2003},
  volume={424},
  pages={416-420}
}
At the northern Cascadia margin, the Juan de Fuca plate is underthrusting North America at about 45 mm yr-1 (ref. 1), resulting in the potential for destructive great earthquakes. The downdip extent of coupling between the two plates is difficult to determine because the most recent such earthquake (thought to have been in 1700) occurred before instrumental recording. Thermal and deformation studies indicate that, off southern Vancouver Island, the interplate interface is presently fully locked… Expand
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A wide depth distribution of seismic tremors along the northern Cascadia margin
TLDR
The observed depth range implies that tremors could be associated with the variation of stress field induced by a transient slip along the deeper portion of the Cascadia interface or, alternatively, that episodic slip is more diffuse than originally suggested. Expand
Seismic reflection imaging of two megathrust shear zones in the northern Cascadia subduction zone
TLDR
Deep seismic reflection data from the northern Cascadia subduction zone are presented that show that the inter-plate boundary is up to 16 km thick and comprises two megathrust shear zones that bound a >5km-thick, ∼110-km-wide region of imbricated crustal rocks. Expand
Geodetic and seismic signatures of episodic tremor and slip in the northern Cascadia subduction zone
Slip events with an average duration of about 10 days and effective total slip displacements of severalc entimetres have been detected on the deeper (25 to 45 km) part of the northern Cascadia… Expand
Local thickening of the Cascadia forearc crust and the origin of seismic reflectors in the uppermost mantle
Seismic reflection profiles from three different surveys of the Cascadia forearc are interpreted using P wave velocities and relocated hypocentres, which were both derived from the first arrival… Expand
Relationship between the Cascadia fore‐arc mantle wedge, nonvolcanic tremor, and the downdip limit of seismogenic rupture
Great earthquakes anticipated on the Cascadia subduction fault can potentially rupture beyond the geodetically and thermally inferred locked zone to the depths of episodic tremor and slip (ETS) or to… Expand
Probable low-angle thrust earthquakes on the Juan de Fuca- North America plate boundary
In 2004, two clusters of earthquakes occurred in the central part of the Cascadia forearc, which displays several characteristics indicative of along-strike and downdip variations in plate coupling.… Expand
Downdip landward limit of Cascadia great earthquake rupture
[1] This paper examines the constraints to the downdip landward limit of rupture for the Cascadia great earthquakes off western North America. This limit is a primary control for ground motion hazard… Expand
Cascadia low frequency earthquakes at the base of an overpressured subduction shear zone
TLDR
The authors show that slow slip earthquakes at the Cascadia subduction zone occur immediately below a 6-10 km-thick shear zone, in which slab-derived fluids are likely trapped at near-lithostatic pore pressures. Expand
SAHKE seismic‐scatter imaging of subduction beneath Wellington, North Island, New Zealand
Scattering reflectivity analysis of onshore seismic data (Seismic Array HiKurangi Experiment) images slab geometry and crustal structure at a geodetically locked subduction boundary. A broad seismic… Expand
Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust
The unknown onshore extent of megathrust earthquake rupture in the Cascadia subduction zone represents a key uncertainty in earthquake hazard for the Pacific Northwest that is governed by the… Expand
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References

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TLDR
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