Figure 1. Interseismic deformation vectors (black arrows) and displacements during the
2003 Cascadia slow earthquake (red arrows).
Figure 2. Bottom Panel: Daily longitude positions record the last three
episodic slow earthquakes in Cascadia (thick blue lines).
Top panel: Example of Gaussian- wavelet transform used to pick transient onset times.
Figure 3. Variable-slip faulting along the Juan de Fuca- North America plate
interface, inverted from geodetic GPS data using non-negative least squares, shows event nucleation
beneath the southern Puget basin and bi-lateral propagation of ~300 km over six weeks.
Inversion of continuous GPS measurements from the Pacific Northwest show the 2003 Cascadia slow earthquake to be among
the largest of ten transients recognized here to date. Twelve stations indicate that transient creep propagated
bi-directionally from rupture initiation in the southern Puget basin, reaching 300 km along strike over a period of
seven weeks.
The 2003 event produced, for the first time, resolvable vertical subsidence, and horizontal displacement reaching six mm
in southern Washington State.
Our new time-series and site data pages hightlight these results using PANGA, IGS, CORS, and SNARF networks. Here we provide
"Raw", "Detrended" and "Cleaned" GPS data. Each time-series plot is easily user customized.
Slow earthquake resources
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