The Bonga field is located offshore deepwater Nigeria. Part of the second phase of the development comprised five frac-pack treatments executed in a multidarcy environment. With permeability variations from 1 to 7 darcies, the salt-tolerant fracture fluid had efficiencies of about 40%, compared to the 10 to 15% most commonly achieved. Use of such a high-efficiency fluid substantially reduced pump rates and horsepower requirements.

All five treatments were performed from a stimulation vessel, three of the treatments with the conventional two-trip technique and two using the single-trip perforating and frac-packing technique. The single-trip system reduced completion time by 1 to 2 days as compared with time using a conventional system.

This paper discusses Bonga Phase 2 frac-pack treatments and compares the two techniques from cost savings and well performance standpoints based on field applications. Authors detail the design, execution, and evaluation of the treatments and discuss the fluid system and the lessons learned during the completions campaign.