Relevance Of H/V Spectral Ratio Technique For Bucharest City

摘要: We investigate the validity and relevance of H/V spectral ratio technique in particular case Bucharest City which was strongly affected by 4 March 1977 (Mw = 7.4) damaging earthquake. Our study shows that coincidence predominant frequency response entire succession Quaternary unconsolidated deposits above Frătesti layers (f approx. 0.7 Hz) underlying urban area with main component Vrancea seismic source spectrum for largest shocks > 7) is critical controlling strong ground motion properties. When applied to noise data, reproduces sedimentary cover beneath city relatively uniform distribution this structure over city's area. An analysis data on earthquakes different sizes resonance becomes effective only major practically negligible events below magnitude 7. Consequently, we recommend avoiding any extrapolations from small moderate large when making microzonation map