| [[file:Mth14ch07f05.jpg|thumb|300px|{{figure number|5}}Map of recovery processes active in Prudhoe Bay field. Gravity drainage is the dominant recovery mechanism in the north-central part of Prudhoe, whereas the eastern, southern, and western field margins are under active waterflood and miscible-injectant recovery.]] | | [[file:Mth14ch07f05.jpg|thumb|300px|{{figure number|5}}Map of recovery processes active in Prudhoe Bay field. Gravity drainage is the dominant recovery mechanism in the north-central part of Prudhoe, whereas the eastern, southern, and western field margins are under active waterflood and miscible-injectant recovery.]] |
− | Four reservoir-depletion mechanisms (gravity drainage/gas-cap expansion, waterflooding, miscible-gas flooding, and gas cycling) operate simultaneously at Prudhoe Bay ([[:file:Mth14ch07f05.jpg|Figure 5]]; Szabo and Meyers<ref name=Szaboandmeyers_1993>Szabo, D. J., and K. O Meyers, 1993, Prudhoe Bay: Development history and future potential, Paper No. 26053: Society of Petroleum Engineers Western Regional Meeting, Anchorage, Alaska, p. 1-9.</ref>). Each process is managed to work in concert with the existing fluid distribution (expanding gas cap, injected water, and oil), regional geology (2° southward structural dip; intersecting east-west and northwest-southeast fault trends), and field-scale geology. Interbedded conglomerates, sandstones, and mudstones create a spatially variable rock volume containing permeabilities ranging from a few millidarcys to tens of darcys. Tailoring horizontal wells and their completions to suit specific engineering and geologic conditions significantly increases primary and tertiary recovery from fine-grained sandstones and conglomerates in Prudhoe Bay field. | + | Four reservoir-depletion mechanisms (gravity drainage/gas-cap expansion, waterflooding, miscible-gas flooding, and gas cycling) operate simultaneously at Prudhoe Bay ([[:file:Mth14ch07f05.jpg|Figure 5]]; Szabo and Meyers<ref name=Szaboandmeyers_1993>Szabo, D. J., and K. O Meyers, 1993, Prudhoe Bay: Development history and future potential, Paper No. 26053: Society of Petroleum Engineers Western Regional Meeting, Anchorage, Alaska, p. 1-9.</ref>). Each process is managed to work in concert with the existing fluid distribution (expanding gas cap, injected water, and oil), regional geology (2° southward structural [[dip]]; intersecting east-west and northwest-southeast fault trends), and field-scale geology. Interbedded conglomerates, sandstones, and mudstones create a spatially variable rock volume containing permeabilities ranging from a few millidarcys to tens of darcys. Tailoring horizontal wells and their completions to suit specific engineering and geologic conditions significantly increases primary and tertiary recovery from fine-grained sandstones and conglomerates in Prudhoe Bay field. |