Breakout Stabilization in Shales - Evidence and Imaging from Large Scale Laboratory Simulation

The paper intends to provide an insight into a large scale experimental campaign incorporating numerical simulations to develop understanding and to, refine the shale failure geometry stabilization mechanism and criteria. The paper also discusses the technical details, considerations and observations of the large scale mechanical rock testing campaign (including triaxial and polyaxial block test) which were carried out on 2 shales. The results of the induced onset of breakout and stabilized breakout geometry were laser scanned, measured and compared with the 3D finite element numerical simulation predictions. The outcome of the research is applied in well design considerations, predicts wellbore stability in 3D and offers valuable insights to the well design team. The results provide visualization of the extent and magnitude of the mechanical wellbore damage whilst drilling in shale formations.