Estimation of Deep Shear-Wave Velocity Profiles in Lima, Peru, Using Seismometers Arrays

Abstract

The estimation of the shear-wave velocity profile in Lima, Peru, was originally performed through surface wave observation in microtremor arrays. In the observation of these surface waves, a low signal problem for long periods was identified that resulted in a poorly done correlation between signals recorded by sensors and, consequently, in difficulty obtaining deep velocity profiles with good resolution. As an alternative, surface wave observation from seismic records was proposed. To confirm the feasibility of this methodology, seismometers were installed in an approximately circular configuration on the campus of the National University of Engineering in Lima. The procedures used to carry out analysis are similar to those used when analyzing microtremor arrays, with the exception that only the coda of seismic records is used for analysis. Results show that the dispersion curve obtained from seismometer arrays agree well with dispersion curve obtained from microtremor arrays and are predominant in a large period range. Finally, the estimated profile is verified using the observed H/V spectrum.