Wavefield composition analysis from three-component beamforming improves thickness estimates of sedimentary layers

Seismic ambient methods have proven increasingly useful for site characterisation and seismic hazard assessment. Methods such as the Horizontal-to-Vertical Spectral Ratio (HVSR) technique have been used to determine the resonance frequency of the shallow sedimentary layer. In this abstract, we use a three-component beamforming algorithm to decipher the composition of the ambient noise. We show that by doing that, we can better understand the major contributor to the HVSR curve and subsequently map the thickness of the top layer either by the Love wave resonance frequencies or the Rayleigh wave resonance frequency.