Gravel Pack

Gravel pack is graded granular material placed in a thin zone around the screens in order to increase the effective hydraulic diameter of the borehole and to help inhibit the movement of sediments into the borehole. Gravel pack material should be chosen to retain most of the unconsolidated formation material, and screen openings are then selected to retain about 90% of the gravel pack. Gravel packs are 100- 200 mm thick.