Fig. 6From: Five parameters for the evaluation of the soil nonlinearity during the Ms8.0 Wenchuan Earthquake using the HVSR methodPredominant frequency F p as weak motion over strong motion versus a PGA and b PGV. The dashed lines indicate the threshold values of PGA and PGV beyond which the site response is nonlinear. The shaded area shows the variation of the level of nonlinearity with PGABack to article page