ConocoPhillips is developing the Magnolia field with a tension-leg platform (TLP) in 4,674 ft of water at Garden Banks Block 783 in the Gulf of Mexico. The wells target multiple zones, resulting in complex directional wells with 50-60° maximum hole angles. The wells are completed using dry trees from the TLP and are produced primarily from massive, fine-grained, Pleistocene reservoirs.rnThese reservoirs require sand control to prevent sand production at the expected drawdowns planned during the life of the wells. To help ensure high-rate, long-life completions, the producing zones are frac packed. The average perforated interval during the initial completion program was 310 ft, with a maximum perforated interval of 571 ft.rnThe typical production-casing string for the wells consists of 103/4-in. casing with an 81/(16)-in. production liner. Drift diameter through the tapered production casing is 9ll2 and 61/2 in., respectively. The 6 /2-in. drift diameter allows using common-sized screens and packers. The wells are generally completed with a 41/2 × 3 1/2-in. tapered-tubing string.rnPremium screens with shunt tubes are used on the wells because of the long deviated intervals. The "frac-pack" stimulation treatments are pumped at rates of 27 to 40 bbl/min with a viscoelastic-surfactant (VES) carrier fluid. Washpipe-conveyed downhole-pressure and -temperature gauges and radioactive tracers are used to help analyze the treatment results.rnThis paper will discuss screen-selection philosophy in silt/ very-fine-sand reservoirs, carrier-fluid selection, perforation strategy, and ability to frac across shale intervals. The paper also will cover the effectiveness of achieving a frac pack with premium screens with shunt tubes, on the basis of downhole-pressure and -temperature and radioactive-tracer information, and will discuss revised operational practices that resulted in zero- to negative-skin completions across long, perforated intervals, which continue to produce sand-free after extreme reservoir depletion.
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