Very-Low-Frequency Earthquakes (VLFE) in SVI and Grid Moment-Tensor Inversion

For details on GCMT inversion method, see Ito et al., GJI, 2006.

Forward Modelling of VLFE Waveforms

An Example of VLFE in May 2008 ETS Episode

Compare to A Recent Study by UW Group

La Rocca et al. (Science, 2009)

Kao et al. (JGR, special issue)

PGC Array: ~200 m Spacing

Spatial-Temporal Distribution of3 A-class ETS Episodes

(Near) Future Efforts• A joint study (or studies) applying various tremor location methods to the same tremor dataset to determine what waveform patterns are best resolved by which method (pros and cons) and why.

• Establish a semi-permanent seismic array in southern VI for mid-/long-term ETS observations (PGC Array).

• Continue VLFE CMT inversion for previous ETS episodes.

• Identify ETS migration details, and their relationship w.r.t. structures.

• Setting up TAMS for WA, OR, and possibly CA.