1. n. [Well Completions]
A type of sand-control completion in which the gravel pack screen is packed off in an openhole section with no casing or liner to support the producing formation. The openhole interval is often prepared by underreaming a section of reservoir below the last casing shoe. When the treatment is to be applied on an existing well, a section of casing may be milled out.
See: casing, casing shoe, gravel pack, gravel-pack screen, sand control