This paper compares two recent subsea completions in water depths greater than 2,600 feet in the Gulf of Mexico, and how their different configurations enable selective production from three separate gravel packs through an "intelligent system" with two remotely operated sleeves. The "intelligent system" enables a zone change with remotely controlled sleeves that are functioned from the host production platform.

One completion is designed to produce the two lower gravel packs and, with the upper gravel pack, is capable of future production without subsea well intervention. See Figure 1 to see the flow paths from the gravel packs into the production tubing through the remotely operated sleeves of the "intelligent system". For this completion design the two lower gravel packs will initially flow into the production tubing through the lower remotely operated sleeve of the "intelligent system". To change zones for production, the lower "intelligent" sleeve will be remotely closed to isolate the lower zones and the upper sleeve will be remotely opened to produce the upper zone.

Figure 1

Intelligent Completion with 2 Lower Zones Commingled

Figure 1

Intelligent Completion with 2 Lower Zones Commingled

The other, more complex completion is configured to produce the two upper gravel packs through the upper remotely operated sleeve of the "intelligent system". The gravel pack assemblies are more complicated to enable annular flow from the two upper gravel packs. This completion design still has the same flexibility to change zones and without well intervention. See Figure 2 to see the flow paths from the gravel packs into the production tubing through the remotely operated sleeves of the "intelligent system".

Figure 2

Intelligent Completion with 2 Upper Zones Commingled

Figure 2

Intelligent Completion with 2 Upper Zones Commingled

Another very important aspect of a successful subsea intelligent completion is the various methods to isolate the gravel packs until the production tubing and intelligent system is installed. These stacked reservoirs usually have different pore pressures, which complicate the gravel pack pumping process and make isolation necessary. There are several mechanisms used to isolate these reservoirs from each other, but this paper will show the use of pressure operated communication devices (POCD) within the gravel pack assemblies.

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