Fig. 3

Hydraulic head \(h_{\mathrm{w}}\) dependence of the styles (in marker shapes) and the total number N of the slides of the \(H \simeq 20\) cm, \(L = 13.5\) cm cliffs. a Front views of the landslides at their final stages for three different \(h_{\mathrm{w}}\) values. The cliff width is \(W = 35\) cm. Left: the \(h_{\mathrm{w}} = 1.8\) cm (run 13, \(h_{\mathrm{w}} / H = 0.09\), Additional file 1: Movie S1) case at \(t = 2940\) s after a slide is triggered. Center: the \(h_{\mathrm{w}} = 8\) cm (run 14, \(h_{\mathrm{w}} / H = 0.40\), Additional file 2: Movie S2) case at \(t = 900\) s after 2 slides are triggered, followed by a spread. The lower (upper) terrace formed after the second (first) slide. Right: the \(h_{\mathrm{w}} = 15\) cm (run 7, \(h_{\mathrm{w}}/H = 0.75\)) case at \(t = 180\) s after a slide is triggered, followed by flooding. b N versus \(h_{\mathrm{w}}\) (a total of 11 runs; there are 2 runs with \(N = 0\)). The upper horizontal axis is in the \(h_{\mathrm{w}}/H\) scale. The 3 large markers correspond to the runs shown in a