Estimation of Shear Wave Velocity Structures in Metro Manila, Philippines from Microtremor Array Measurements

摘要

Local site amplification is essential when performing seismic hazard analysis. It is considered to be the factor in determining the distribution on severity of earthquake ground motion of an area. Therefore, detailed velocity structures needs to be categorised to identify the sites that are susceptible to strong ground shaking during near field earthquakes. This paper presents the microtremor array measurements that identify the velocity structures in 28 sites of Metro Manila, Philippines. Spatial Autocorrelation (SPAC) method is used in the analyses of microtremors to obtain the surface wave phase velocities and applied the genetic algorithm (GA) in the inversion of phase velocities to infer the shear wave velocity profiles.