Towards landslide predictions: two case studies

In a previous work (J. Geophys. Res. (2004)), we have proposed a simple physical model to explain the accelerating displacements preceding some catastrophic landslides, based on a slider-block model with a state- and velocity-dependent friction law. This model predicts two regimes of sliding, stable and unstable leading to a critical finite-time singularity. This model was calibrated quantitatively to the displacement and velocity data preceding two landslides, Vaiont (Italian Alps) and La Clapière (French Alps), showing that the former (resp. later) landslide is in the unstable (resp. stable) sliding regime. Here, we test the predictive skills of the state- and velocity-dependent model on these two landslides with a variety of techniques using (i) a finite-time singularity power law, (ii) the state- and velocity-dependent friction law and (iii) resummation methods extrapolating from early times. For the Vaiont landslide, our model provides good predictions of the critical time of failure up to 20 days before the collapse. Tests are also presented on the predictability of the time of the change of regime for La Clapière landslide.