Open AccessThunder‐induced ground motions: 2. Site characterization
Author(s) -
Lin TingL.,
Langston Charles A.
Publication year - 2009
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2008jb005770
Subject(s) - rayleigh wave , geology , surface wave , dispersion (optics) , explosive material , rayleigh scattering , thunder , seismology , geophysics , optics , physics , meteorology , chemistry , organic chemistry
Thunder‐induced ground motion, near‐surface refraction, and Rayleigh wave dispersion measurements were used to constrain near‐surface velocity structure at an unconsolidated sediment site. We employed near‐surface seismic refraction measurements to first define ranges for site structure parameters. Air‐coupled and hammer‐generated Rayleigh wave dispersion curves were used to further constrain the site structure by a grid search technique. The acoustic‐to‐seismic coupling is modeled as an incident plane P wave in a fluid half‐space impinging into a solid layered half‐space. We found that the infrasound‐induced ground motions constrained substrate velocities and the average thickness and velocities of the near‐surface layer. The addition of higher‐frequency near‐surface Rayleigh waves produced tighter constraints on the near‐surface velocities. This suggests that natural or controlled airborne pressure sources can be used to investigate the near‐surface site structures for earthquake shaking hazard studies.