Theory 70/Wilson cycle/Onset phase
Rifting Starts on a Strength Threshold
The claim
Continental rifting begins above a threshold in the ratio of extensional stress to lithospheric strength, so a hot thin plate rifts where a cold thick one does not.
01Mechanism
Extension must overcome the strength of the plate; the ratio determines failure.
02Prediction
Rifting should track the ratio.
03Refutation
Rifting tracking stress alone would remove strength.