Bergzerreißung and Talzuschub

The terms Bergzerreißung (mountain splitting) and Talzuschub (closing-up of the valley) describe the morphological features of large down-hill movements. Their structural peculiarities are determined by a zone of internal rotation beneath a zone of only small internal deformation. From these data we can deduce a general plan of deformation of slopes. When assuming a linear distribution of shear stress they also allow the determination of the mechanical properties of rock masses. Comparing rock and ice in general we may conclude that these mechanical properties, mainly the flow law expressed by a power function, are valid also in deep parts of the earth crust.