Volcano Island
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Transcript of Volcano Island
Triggered tremor may simply be clock-advanced failure, which could make it useful
as a widely available ambient tremor and perhaps slow slip ‘meter’.
Volcano Island
Triggering depends on more than wave amplitude.
Posited Triggering Wave Amplitudes Vancouver Island (Cascadia)
Triggering depends on more than wave amplitude.
Posited Triggering Wave Amplitudes Vancouver Island (Cascadia)
Rubinstein et al. (2008)
Fault population with failures at a ~constant rate.
Clock-Advance Model
Perturbation advances (or delays) the failure times.
Clock-Advance Model
€
r(t) =r0(t)
(1−dΔt
dTf)perturbed rate
unperturbed rate
relationship between clock-advance & fault proximity to failure
[This underlies the ‘Dieterich (1994)’ aftershock model. Used in Beeler & Lockner (2003), Kaneko & Lapusta (2008), & others.]
Rate tests.
Cascadia Ambient Tremor Probabilities & Teleseism Origin Times
Sic
huan
P-W
aves Ambient Tremor
Triggered Tremor
2008 Wenchuan Earthquake Waves Arrive During ETS Event & Trigger Tremor
seconds
Per
u P
-Wav
es
Comparable 2007 Peru Earthquake Waves Arrive During Inter-ETS Time -> No Triggering
seconds
Denali Waves -> Instrumentation Matters!
PNSN
PN
SN
PN
SN
& C
NS
N
Amplitude tests: bigger perturbations -> bigger summed tremor.
Amplitude tests: bigger perturbations -> bigger summed tremor.
Suggestion of a scaling… data are noisy and scant.