September 2002
Columns
Drilling developments
JIP on underbalanced drilling in marine environments. Currently, underbalanced drilling (UBD) procedures have been used in about 100 marine locations by most major operators. Primary use has been where casing is set and cemented into or on top of a subnormal or pressure-depleted formation, which is then drilled under- or near-balanced to avoid lost circulation and reservoir damage. And new dual-gradient drilling techniques may be viewed as a subset of UBD."
In U.S. OCS waters, MMS has required wells to be drilled overbalanced. For it to allow UBD in wells under its jurisdiction, it must be shown that it can be conducted in a safe and efficient manner. To that end, Maurer Technology and Texas A&M are going to conduct a joint industry research project (JIP) to enable state and federal regulators, and the drilling industry to be proactive in defining situations where UBD can be successfully applied offshore. This project will also extend to other international marine areas and regulators.


