Liquefaction Potential and Vs30 Structure in the Middle-Chelif Basin, Northwestern Algeria, by Ambient Vibration Data Inversion

The Middle-Chelif basin, in northwestern Algeria, is located a seismically active region. In its western part lies the El-Asnam fault, thrust fault responsible for several strong earthquakes. most important being earthquake (Ms = 7.3) of 1980. present study, ambient vibration data with single-station and array techniques were used to investigate dynamic properties ground estimate Vs30 structure main cities basin. Soil resonance frequencies vary from 1.2 8.3 Hz maximum amplitude 8.7 in. Collapsing behavior has also been demonstrated west city El-Attaf, reflecting potential liquefaction. A variation map soil classification each obtained mainly by inversion HVSR Rayleigh wave dispersion curves. Finally, an empirical prediction law basin was proposed.