Decomposition of high-frequency seismic wavefield of the Strombolian-like explosions at Erebus volcano by Independent Component Analysis.

The characteristics of the Strombolian-like activity at Erebus volcano (Antarctica) are evidenced by decomposing the wavefield of the explosion-quakes associated with the bursting of gas slugs at the surface. The decomposition is achieved by adopting a non-linear technique operating in time domain, that is, independent component analysis. Although the spectral properties and polarization analysis of the recorded signals provide evidence of an overall complex volcanic structure, the decomposed waves indicate well-polarized phases with high rectilinearity. Slightly different directions in azimuth can be individuated compatible with different and close vibrating solid structures like conduits in the summit volcanic plumbing system.