Fig. 10
![Fig. 10](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40623-017-0718-z/MediaObjects/40623_2017_718_Fig10_HTML.gif)
Comparison of the NL components of site amplification for different descriptions of the loading level, for the one-SCP ANN model using V S30. Each panel represents the (soft/stiff) site amplification at a given oscillator period as a function of a loading parameter. The three columns correspond to three different oscillator periods (0, 0.2 and 1.0 s). The three rows correspond to different choices for the loading level: strain proxy PGVsoft/V S30 on top, spectral ordinates at the stiff-site PSAstiff (T) in the middle and PSAstiff at the 0.0 s (bottom). As shown in Fig. 9, the site amplification factors (SR: Eq. 3) are calculated for three distances: 30 km, 50 km and 75 km, for which the variation of loading level corresponds to magnitude variations between 5 and 7 (for a fixed focal depth equal to 10 km)