Prepacking perforations with gravel - PetroWiki

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Prepacking can be defined as any method that intentionally places gravel into the perforation tunnels. Filling of perforation tunnels can be accomplished either with a dedicated operation before performing the gravel pack or simultaneously with it. The technique used is normally dictated by well parameters. Gravel packing cased-hole completions in vertical and deviated wells are more common than openhole completions, particularly in shaley reservoirs. However, cased-hole gravel packs have an important requirement that is easily overlooked.