Well completions in weakly consolidated formations

摘要

Weakly consolidated hydrocarbon fluid bearing earth formation zones having a cohesive strength of about 500 psi or less are produced by completing a well penetrating the zone and initiating production of solids laden fluid from the zone through the well to generate a near wellbore cavity. Production of solids laden fluid is continued until the cavity grows to a point wherein the fluid velocity across the cavity face decreases to a value below the solids particulate transport velocity wherein continued production of fluid will result in a very low or negligible rate of production of solids particulates. Solids particulates are separated from the produced mixture at the surface, the solids are treated to reduce the particle size and reinjected in a slurry into a disposal well for disposal in a hydraulically fractured or disaggregated formation zone remote from the production zone. Cavity growth and production may be carried out by throttling a free flowing well or by artificial lift, preferably utilizing power fluid and a hydraulic jet pump or gas lift techniques.