Surface wave radiation
Larsen et al. (2009) EOS
2008 eruption of Okmok
strongtremor
OKWE RSAM
7/13 7/20 7/27 8/03 8/10 8/17
ampl
itude
(arb
. un
its)
Okmok eruption seismicity
VLP tremor during Okmok eruption
VLP tremor has been previously reported by De Lauro et al. (2005) at Stromboli
Stations used for tremor analysis
Comparison of Amplitude Spectra
OKSOz-OKFGz inter-station times
Histograms of 10 inter-station times
Tremor located NNW of Cone D
Haney (2010) JGR, in press
new cone Cone D caldera rim
north south
Similar phase velocity for Love waves, so a similar inter-station time expected
Horizontal components
Not similar to ZZ or RR
Sign flip on OKFGt
Radiation pattern for a vertical CLVD
Azimuth constrained by Love waves, source depth by Rayleigh waves
Rayleigh radiation: VLP tremor depth
approx. edge of caldera
Masterlark, Haney, et al. (2010) JGR
Ambient noise tomography of Okmok
Radiation pattern for a vertical CLVD
Haney (2010) JGR, in press