Lost circulation while running casing, pre-cement job mud circulation, and cement placement can result in additional remediation, create challenges in achieving zonal isolation objectives, and potentially impact well integrity. Several mitigation methods are available to address lost circulation challenges. However, the focus of this paper is on prevention.
This presentation summarizes the field application of wellbore strengthening in deepwater Gulf of Mexico to achieve zonal isolation objectives. The design, execution, and post-well analysis of several wellbore strengthening applications in a variety of sands from shallow and soft overburden sands to deep producing reservoir sands with depletions greater than 4,000 psi, are discussed. A detailed case study for one of the wells is provided.
The track record of successful wellbore strengthening treatments performed demonstrates the potential for achieving adequate annular cement placement and zonal isolation in narrow pore pressure and fracture gradient environments.