Because the confining force increases, the rise in resistance to longitudinal crack propagation leads to a gradual transition of shale failure manner from longitudinal to inclined shear failure that reflects an escalation in rock plasticity. When the confining stress reaches 30 MPa, there remain area shear microcracks around the https://directoryweburl.com/listings13609780/not-known-factual-statements-about-wellbore-stability