Centrifuge modelling of active seismic fault interaction with oil well casings

Interaction of active seismic faults with oil well casings has been investigated to evaluate the interaction process and determine approaches to mitigate damage and deformation of the well casing. The methodology used was a 2-way approach consisting of (1) undertaking a series of unscaled physical model tests in a geotechnical centrifuge using on simplified geological analogues and (2) validation of 3D numerical models by verification and calibration to the experimental test results. Two type of geological scenarios are presented: an unconsolidated cohesionless deposit and a bedded rock mass deposit with 60° dip bedding. A basement discontinuities of displacement (normal faulting) and of slope and displacement (sloped base de-formation) were introduced. The interaction with the propagating faults through the model was studied with post-experiment dissection and PIV analysis. These information were used to calibrate a numerical models and draw appropriate conclusions with regard to mitigation methods.