A small operator drilling its first well in Reeves County in the Delaware Basin was unable to execute a liner cement job, leading to discussions about abandoning the well due to anticipated difficulties in achieving a successful multistage completion without annular isolation. However, given the investment in drilling, the operator decided to evaluate stimulation options. The ideal stimulation would maximize isolation between stages as well as reduce screenout risk. Plug-and-perf (PnP) opened too many conduits to the wellbore, and certainty of frac placement seemed low. However, without sleeves or external packers in place, perforations needed to be created between each stage. Ultimately, a coiled-tubing-deployed system with the ability to jet-cut perforations was selected as the method with the highest potential for success. Perforations were cut with sand slurry pumped down 2-in. coiled tubing and through nozzles in the cutting sub. At each stage, four perforations were cut at 90° phasing. Fracs were pumped down the annulus between the coiled tubing and the 4-1/2-in. liner with a maximum frac rate of 20-25 bbl/min. As an added benefit, the coiled tubing enabled real-time pressure monitoring along with the ability to dilute sand concentration during a frac and to circulate out sand from any screenouts. The operator originally planned the stimulation for 20 stages, but, based on early success, extended the job to the length of the wellbore, with a total of 50 stages at 80-ft spacing. The jet-perforating tool cut all 50 stages without requiring a trip to surface for repair or replacement, and the bridge plug seal element provided complete wellbore isolation at every stage, while sustaining minimal wear. Data from the downhole memory gauge located below the isolation bridge plug revealed that almost 60% of the stages experienced either near or far-wellbore pressure communication between stages. Despite this pressure communication, sand cleanouts were not required, although one was performed during flowback. This well has been producing slightly under the regional type curve but is projected to exceed it. Despite the initial concerns about completion feasibility, the lateral was stimulated effectively and successfully without stretching economic or technological barriers. This paper fully describes the completion options, the selection criteria, and the stimulation operation.
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