1. Summary of triggering of non- volcanic tremor in Cascadia Justin Rubinstein

2. Tremor is Modulated by Love Waves

3. How things work * Love waves Earthquake in Alaska

4. Tremor Modulated by Stress Amplitude Rubinstein et al, 2007

5. Rubinstein et al, submitted Does Amplitude Control Triggering? Rubinstein et al, 2009

6. Peng et al, submitted Does Amplitude Control Triggering in Parkfield?

7. Peng et al, in prep Does Amplitude Control Triggering in Taiwan?

8. Tremor correlates with tides Shelly et al., (2007)

9. Recordings of 3 ETS episodes Tremor“Noise”

10. Tremor spectra for the 5 arrays Rubinstein et al, 2008

11. Amplitude variation with 12.4-hr period 12.4-hr tides 30% effect 24-hr probably similar magnitude

12. Summary & Conclusions Tremor is triggered by very small dynamic stresses from teleseismic EQs (10s of KPa)Tremor is triggered by very small dynamic stresses from teleseismic EQs (10s of KPa) Tremor is modulated by the very small stresses of the earth and ocean tides (~10KPa)Tremor is modulated by the very small stresses of the earth and ocean tides (~10KPa) Ambient stress ~10 5 times strongerAmbient stress ~10 5 times stronger Tremor is occurring on faults that are very close to failureTremor is occurring on faults that are very close to failure –Fluids? Low Friction? Just Close to Failure?

14. Triggered Tremor = ETS Tremor

15. Tremor vs aligned 12.4-hr bumps Array SO for 2004 PA for 2005 BS for 2007