One 4D Geomechanical Model and its Many Applications

We present a case study of model building, calibration and application of a 4D geomechanical flow model. Model building uses seismic inversion volumes to constrain a geological facies model, followed by upscaling to a reservoir simulation model and history matching. Similarly a 3D geomechanical model is built and calibrated. Production and injection processes are computed using a fully coupled finite element based geomechanical flow simulator, solving fluid flow and geomechanics equations simultaneously at each time-step on the same computational mesh.

The applications of the presented simulations include:

1. wellbore stability assessment for drilling inclined infill wells, as well as the change in mudweight window over time for planned wells during injection and production from the field,
2. calculation of maximum allowable injection pressures during hydraulic stimulation to avoid out-of-zone growth of hydraulic fractures,
3. evaluation of risk of fault re-activation during a range of production scenarios for pressure support in order to establish safe operational limits for pressure support, and
4. forward modelling of the expected time-lapse seismic signal at various stages of production and comparison with time-lapse seismic test lines.