## 3 Analysis of Temporal and Spatial Distribution Characteristics of Landslide Surge
### Analysis of Factors Influencing the Head Wave Crest
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Area**} & **Testing** & \multicolumn{4}{c}{**Head Wave Crest (cm)**} & \multicolumn{4}{c}{**Maximum Wave Height (cm)**} \\  & **Point** & **MLS1** & **MLS2** & **MLS3** & **MLS4** & **MLS5** & **MLS1** & **MLS2** & **MLS3** & **MLS4** & **MLS5** \\ \hline \multirow{3}{*}{
\begin{tabular}{c} Diversion \\ area \\ \end{tabular} } & h01 & 0.69 & 1.79 & 2.24 & 3.27 & 4.28 & 0.82 & 1.92 & 3.86 & 3.98 & 5.29 \\  & h02 & 0.65 & 1.60 & 1.99 & 2.48 & 3.61 & 0.76 & 1.95 & 3.14 & 3.31 & 4.30 \\  & h03 & 0.37 & 1.31 & 2.13 & 3.02 & 3.70 & 0.37 & 1.31 & 3.14 & 3.02 & 3.70 \\  & h04 & 0.31 & 0.98 & 1.74 & 2.64 & 3.37 & 0.31 & 0.98 & 2.87 & 2.88 & 3.90 \\  & h05 & 0.32 & 1.12 & 1.83 & 2.66 & 3.39 & 0.22 & 1.12 & 2.38 & 3.29 & 3.39 \\  & h06 & 0.29 & 1.00 & 1.80 & 2.41 & 3.26 & 0.59 & 1.12 & 2.15 & 2.87 & 3.80 \\  & h07 & 0.24 & 0.86 & 1.79 & 2.40 & 3.00 & 0.57 & 1.32 & 2.59 & 3.87 & 3.59 \\  & h08 & 0.77 & 1.48 & 2.41 & 2.65 & 3.33 & 0.84 & 1.65 & 3.30 & 2.87 & 3.44 \\  & h09 & 0.66 & 1.33 & 3.39 & 4.25 & 5.01 & 0.66 & 1.50 & 3.95 & 4.54 & 5.07 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Maximum wave height and head wave crest at testing points under different volumes. the middle of the curved area, and testing point h09 is located at the end of the curve. The cross-sectional area of the testing points h07 decreases compared to h08; meanwhile, the corresponding wave height increases. This phenomenon is inconsistent with the law of topographic similarity area, but the amplitude of the wave heights of the testing points is much larger than that of the topographic similarity area, whereas the cross-sectional area of the testing point h09 relative to the testing point h08 decreases significantly. This is due to the large change in the water depth of the river course in front of the dam when the river width changes insignificantly, but the height of the head wave at the testing point h09 relative to the testing point h08 decreases. However, the head wave crest at testing point h09 decreases relative to testing point h08, which is contrary to the law of topographically similar area. The head wave crest cuts down when there is a big turn in the river. For the testing points h07 and h09, the cross-sectional area of the testing points greatly decreased, and the head wave crest of both of them increase, so it can be seen that when the river does not have curved areas, it still follows the law of the topographic similarity area. But when judging the change in the head wave crest at the end of the curve, it is necessary to take into account the effect of the reduction in the height of the wave brought about by the curve. Based on the analysis of the head wave crest along the river, when the river width and water depth change a little and the steady wave moves forward, the cross-sectional area of the river is the main factor that determines the trend of the head wave crest. When the area includes large changes in the width of the river and diversion, the head wave crest of the river will decrease when passing through the area. Moreover, when there is a curve in the river, the head wave crest in the middle part of the bend increases due to wave reflection. The wave height at the end of the curve decreases compared to the middle part of the curve, and the height of the head wave crest decreases when the wave propagation completes the turn. In order to investigate the effect of volume on the variation in head wave crests along the river, the head wave crests of the five sets of test landslide surges are plotted in Figure 8. The analysis of the data in the figure indicates that the five sets of data have the same pattern in the topographically similar area, meaning that the change in the cross-sectional area of the river course in the topographically similar area is the main factor affecting the head wave crest of the landslide surge.