The discussion on flow started in the previous chapter. The basic understandings of the different creep regimes will now be elaborated upon by introducing creep laws to quantify the rock flow.

In order to do so, first the quantity of viscosity is explained. After that, description of rock flow starts with some visco-elasticity models for rock deformation. The flow description is continued with non-newtonian creep, strain softening and strain-rate softening. Resulting are flow curves, creep laws and lithosperic strength curves which are presented in paragraphs 6 to 9. The chapter is concluded with geological applications of lithosperic strength diagrams.