Extracting coherent coda arrivals from cross-correlations of long period seismic waves during the Mount St. Helens 2004 eruption

[1] We computed cross-correlations of seismic waves generated by Long-Period (LP) events in the frequency band [0.8–2.2 Hz]. The data were recorded in the vicinity of Mount St Helens (MSH) during an eruptive period from September to December 2004. The time symmetric coherent coda arrivals of the time-derivative of the cross-correlation function (DCF), resulting from scattering and topographic effects in MSH area, correspond to arrivals of the Green’s function (GF) between the two stations. The DCF waveforms computed on an hourly basis show a remarkable consistency over time periods of several hours but show temporal variations on longer time-scales. We investigated the emergence rate of the symmetric arrivals of the DCF and discussed their potential applications for volcano monitoring. Citation: Sabra, K. G., P. Roux, P. Gerstoft, W. A. Kuperman, and M. C. Fehler (2006), Extracting coherent coda arrivals from cross-correlations of long period seismic waves during the Mount St. Helens 2004 eruption, Geophys. Res. Lett., 33, L06313, doi:10.1029/2005GL025563.