Automatic discrimination and fast wavefield decomposition of tectonic and volcano-tectonic (VT) earthquakes by Independent Component Analysis

Abstract

The discrimination of seismic events from the ambient background noise, the wavefield decomposition into basic wave-packets and the identification of the main phases are fundamental tasks in the study of the earthquake source processes. In the last years, the Independent Component Analysis (ICA), a technique used in advanced signal processing to separate statistically independent sources (Hyvärinen et al., 2001), has found relevant and interesting application in the seismological field both for event detection and discrimination purposes (Ciaramella et al., 2011, Capuano et al., 2017), as well in providing spectral decomposition of the wavefield into basic wave-packets related to the source and their polarization pattern (Capuano et al., 2016). Recently, De Lauro et al. (2016) have shown the efficiency of the ICA in decomposing seismic wavefield of volcano-tectonic (VT) earthquakes recorded at Campi Flegrei by the local network into basic wave-packets naturally polarized in the vertical and horizontal planes, providing a clear identification and separation of the P and S waveforms in time domain...[continua nel file allegato]