Frictional Sliding and the Crustal Stresses

Jamison and Cook (1978) analysed the state of stress in the crust based on a selected set of fifty 3-D stress measurements from all over the world. They found a linear relationship between the maximum shear stress and half the sum of the maximum and minimum principal stresses. This indicates that the Coulomb failure criterion or equivalently the law of friction may give a good description of the crustal stresses. In this paper I illustrate some of the consequences if the Coulomb failure criterion or friction determines the state of stress in the upper crust. As will be seen this simple assumption leads to interesting interpretations concerning the crustal rock mechanical conditions.