Some Pitfalls Associated with Dominant Higher-Mode Surface-Wave Inversion

B028 SOME PITFALLS ASSOCIATED WITH DOMINANT HIGHER-MODE SURFACE-WAVE INVERSION 1 ADAM O’NEILL TOSHIFUMI MATSUOKA KAZUHIKO TSUKADA Department of Civil and Earth Resources Engineering Kyoto University Yoshida KYOTO 606-8501 Japan Low- and high-velocity layer dispersion Dominant higher modes of seismic surface waves are generated in low- and high-velocity layer cases typical of many engineering sites. Figure 1 shows three synthetic models and Figure 2 the ‘effective’ dispersion curves from full-waveform synthetic seismograms overlain on the plane-wave ‘modal’ dispersion curves. These types of dispersion curves both synthetically generated and observed at field sites were successfully inverted by linear optimisation using a forward