Reservoir pressure and Fluid sampling

We plan to take reservoir pressures and hopefully fluid samples from
a very deep well (30,000+ft TVD, 8-1/2" hole) using a wireline
deployed tool. Unfortunately we anticipate there being numerous sand
bodies exposed and the overbalance pressure across many of them will
probably be in excess of 3000psi.

We will maintain the synthetic based mud with the appropriate
materials in order to maximise our likelihood of forming a thin,
impermeable filter cake but ultimately, if we do no more than this,
we expect to get the tool stuck. The idea of stripping over 30,000'
of wireline is not attractive.

Other than minimizing the time spent with the logging tool
stationary, does anybody know of any technique that will help
minimize the chance of getting stuck?

9 Answer(s)

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