- Changing pressure in highly depleted formations
- Buildup of 0o to 80o in reactive shale and depleted zones
- Frequent NPT
- Deviated wellbore
- Drilled well successfully to TD despite differentially pressured zones causing two offset failures
- Eliminated NPT by minimizing downhole losses and incidents of differential sticking
- Increased wellbore stability
In Oman’s mature Saih Raw field, an operator had historically experienced sloughing shale, downhole losses, and incidents of differential sticking. Due to the low formation pressures found in such fields, there is often only a narrow operating margin between the pore pressure and formation breakdown. The low pressure does not allow for increased drilling fluid density, therefore causing a dilemma over how to address the borehole stability requirements without inducing fractures.
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