Wellbore instability issues are all too common for operators drilling high-profile deepwater wells in mechanically weak formations with depleted zones and high differential pressures. These challenging conditions can not only disrupt the drilling process – increasing costs and non-productive time (NPT) – but also limit ultimate recoveries. As a result, operators are increasingly recognising the need to take a preventative approach when drilling in environments, such as high-pressure, high-temperature (HPHT) intervals, where wellbore stability may be at risk.
In a new field in offshore Mexico, an operator experienced significant lost circulation while drilling an exploratory well. This prompted the operator to revisit its geomechanics strategy and drilling fluid formulation. After assessing potential solutions, the operator deployed a fluid additive that shields the wellbore during drilling to address instability issues proactively.