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barite plug

1. n. [Well Completions]
A plug made from barite weighting materials that is placed at the bottom of a wellbore. Unlike a cement plug, the settled solids do not set solid, yet a barite plug can provide effective and low-cost pressure isolation. A barite plug is relatively easy to remove and is often used as a temporary facility for pressure isolation or as a platform enabling the accurate placement of treatments above the plug.