Microtremor signal simulation and its application in microtremor exploration

This study synthesized microtremor signals using the normal mode superposition.The dispersion curves of the synthesized microtremor signals were calculated using the spatial autocorrelation method,and the calculated results agreed well with theoretical dispersion curves.The simulation of microtremor signals involves many parameters,which are of great significance for microtremor exploration.As shown by results from numerical experiments of these parameters,the hypocentral distance and array size had a significant influence on the results.Moreover,high-order surface waves should be considered for complex strata,while small-size arrays tended to yield high-frequency dispersion information at quiet observation sites,thus improving the resolution of shallow strata.Therefore,it is necessary to consider the influences of hypocenter distribution,array size,and high-order surface waves on exploration results in microtremor exploration.