Slip tendency is the ratio of the shear stress to the normal stress on a fault or fracture surface:
Slip tendency = (τ)/(σn)
Slip tendency analysis yields useful insights into the nature of the stress tensor and its effects on which fault surfaces may become reactivated and in which direction a fault will slip.
![Slip direction 3DStress Slip direction 3DStress](https://www.swri.org/sites/default/files/styles/facebook_image/public/slip-direction-3dstress-700x422.jpg?itok=AeZ9YSxi)
The relative magnitude of the intermediate principal stress can strongly affect the flow of fluid through a fracture system. This image illustrates a fourfold increase of fracture network participation in fluid flow from a stress state with σ2 halfway between σ1 and σ3 (lower) and one where σ2 ≈ σ1 (upper).
![a fourfold increase of fracture network participation in fluid flow from a stress state a fourfold increase of fracture network participation in fluid flow from a stress state](https://www.swri.org/sites/default/files/styles/facebook_image/public/Sigma-2-effect1920x1584.jpg?itok=YHdR5g0_)
Or call +1 210 522 2122.