Rockfalls

Rockfalls are the downslope movement of loose rocks, either through free fall or by rolling. Rockfalls commonly involve individual boulders, although landslides may be triggered if these boulders impact the slope. Clasts may be dislocated by erosion beneath the clast, freeze-thaw processes or human intervention.

It is well-known that rockfalls can be triggered by earthquakes. However, other trigger mechanisms are much more frequent and more common like seasonal high precipitations and frost weathering. There is no unambiguous criteria to distinguish between those different trigger mechanisms. However, if there is in a region, at a certain time, an increased level of rockfall activity, it will be most likely to assume a strong earthquake as a trigger mechanism.