Site response obtained from array techniques applied to the seismic noise : Two examples in Italy

摘要: The vertical component of the seismic noise has been recorded in two different sites near towns Mercato S. Severino and Benevento Southern Italy by a small aperture array, order to investigate characteristics propagation study site response. Three array techniques have applied investigated sites: Beam Forming, High Resolution Spatial Correlation methods. We used simple geometry for localising possible sources estimating local shallow structure using ambient noise. cross shaped results effective determining phase velocity waves case when is from single localised source; circular on other hand, successfully are distributed. main are: analysis coherent sites, interpreted as Rayleigh waves, reasonable models; M.S.S. Plain space stationary signal, while at possibly produced stable source located close array. Due this evidence, correlation method does not yield satisfactory site. 2–6 Hz spectral peaks can be due effect, considering agreement spectrum those frequencies with theoretical transfer function computed basis model deduced dispersion analysis.