The Role and Importance of Geomechanics in Drilling and Completions

Burgess, Richard M.
Halliburton, Kuala Lumpur, Malaysia.

As operators go after more difficult reservoirs, the need to understand the geomechanical properties of the target environment is becoming increasingly important to both drilling and completion operations.

This oilfield service company's belief is that well placement, design, construction and completion must begin with a geomechanical Earth model of the target area. Fundamentally, effective well design requires an understanding of pore pressures and in-situ stresses to give the best chance of success not only for drilling, but also for completion. Our models use analogue well analysis, local geology, seismic velocities and basin knowledge to resolve the key pressure generating factors, such as the rates of deposition and compaction that can be responsible for the generation of abnormal subsurface pressures. When quality seismic volumes are available, we also generate a seismically-derived pore pressure model that is integrated into the geologic geopressure model calibrated to direct measurements of pressure, in situ stress, and observations of available offset wellbore behavior. This approach help ensure that the analysis honors all available petrophysical, geophysical, and geological information, providing a robust and reliable prediction of subsurface pressure, in-situ stresses and wellbore stability for the target well location. Wellpath optimization analysis is run within the limits of the safe drilling window and further constrained by the effect of stress orientations on completion activity. The result is a program that will prevent or minimize formation fluid influx, shear failure and drilling fluid loss during drilling, and a target well that is optimally aligned for completion operations.

AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012