## 4 Effect from the Rheology Parameters
It can be observed that the difference in terms of the slump profiles is limited at t = 0.4 s. However, the significant differences can be seen at t = 0.8 s at x = -1.4 m\(\sim\)-0.9 m, z = -1.4 m\(\sim\)0.7 m. This indicates that the rheology parameters, especially the yield stress, have important effects on the slump-type landslide. Figure 6: The comparison of free-surface profiles for different un-yield viscosity \(\mu_{A}\) in the Bingham model. Different lines represent different values of \(\mu_{A}\). The dots indicate the experimental results from [PERSON] at: (**a**) t = 0.4 s and (**b**) t = 0.8 s.  
Figure 7: The comparison of free-surface profiles for different yield viscosity \(\mu_{B}\) in the Bingham model. Different lines indicate different values of \(\mu_{B}\). The dots represent the experimental results from [PERSON] at: (**a**) t = 0.4 s and (**b**) t = 0.8 s.  
Figure 8: The comparison of free-surface profiles for different yield stress \(\tau_{y}\) in the Bingham model. Different lines indicate different values of inline-formula\(>\tau_{y}\), the dots denote the experimental results from [PERSON] at: (**a**) t = 0.4 s and (**b**) t = 0.8 s.  
Figure 9: The comparison of the free-surfaces and the slump surface profiles of 8 cases with the combinations of un-yield viscosity \(\mu_{A}\), yield viscosity \(\mu_{B}\), and yield stress \(\tau_{y}\) at: (**a**) t = 0.4 s and (**b**) t = 0.8 s.  
Figure 10 shows the waves excited by the slumps of all simulated cases. The free-surface profiles are affected significantly by the rheology parameters of the slumps. The faster the slump moves, the larger negative wave forms. It is noted that smaller yield stress \(\tau_{y}\) and smaller yield viscosity \(\mu_{B}\) can generate larger tsunamis. In the case of \(\tau_{y}=0\) Pa, the largest negative waves occurred in both t = 0.4 s and t = 0.8 s.  
The synthesized effects from both \(\mu_{\text{B}}\) and \(\tau_{\text{y}}\) can be obtained from the results shown in Figures 9 and 10. The fastest moving speed or the longest moving distance of the slump occurred in the case of \(\left(\mu_{\text{B}},\,\tau_{\text{y}}\right)=(50,\,0)\), while the slowest ones are \(\left(\mu_{\text{B}},\,\tau_{\text{y}}\right)=(500,\,1000)\) and \(\left(\mu_{\text{B}},\,\tau_{\text{y}}\right)=(50,\,2000)\). Changing yield stress can significantly change the moving distance (Figure 9b), while changing yield viscosity has a minor effect. The largest negative wave is excited by \(\left(\mu_{\text{B}},\,\tau_{\text{y}}\right)=(50,\,0)\) while the smallest one is excited by \(\left(\mu_{\text{B}},\,\tau_{\text{y}}\right)=(50,\,2000)\). Also, the results indicate that the major parameter to the wave height is yield stress, and the minor parameter is yield viscosity. However, with the same initial slump elevation and mass, the study cases show that the wave heights are in the same order of magnitude. Of course, if the slump is too sturdy or too sticky, the generated waves are expected to be small or even none. However, this is beyond the scope of this study. The tsunamis excited by landslide is mainly controlled by the initial potential energy of the landslide body [47]. With the same solid material, a subaerial landslide can generate a larger tsunami than a submerged landslide. A landslide body with a larger density can generate a larger tsunami than the one from a lower density [47]. Generally speaking, the tsunami height is proportional to the initial potential energy if the landslide is an un-deformable body. Similar findings are made in this study for the deformable slump. Other than the initial potential energy of the slump, the second and the third effects come from yield stress and yield viscosity, respectively.