Patent ID: 9091159
Filing Date: 2015-07-28
Classification: E21B

Abstract:
1. A process comprising: producing hydrocarbons from a first production well in a subterranean reservoir by a gravity-controlled recovery process, wherein the first production well is paired with an injection well for injecting a fluid to mobilize viscous hydrocarbons in a region in the reservoir, and the injection well and the first production well are substantially horizontal and parallel to one another, the reservoir is formed above a contoured base, hydrocarbons in a region of the reservoir are mobilized by heating or an injected fluid; and when or after the injection well and the first production well are operated in a blowdown phase, or after a production rate from the first production well has reduced, producing hydrocarbons from an unpaired second production well extending below the first production well, wherein the second production well comprises a contour section that follows a contour of a depression on the contoured base and is positioned in a bypassed portion of the region containing hydrocarbons that are mobilized due to operation of the injection well and the first production well and are unproducible from the first production well, to collect mobilized hydrocarbons in the bypassed portion of the region by gravity drainage, without steam injection into the bypassed portion through the second production well or another well below the first production well, wherein mobilized hydrocarbons in the bypassed portion tend to accumulate at the depression, wherein the second production well extends under and across the first production well, and the contour section of the second production well under the first production well is shielded from receiving fluids from the reservoir, so as to limit interference with production of the fluids from the first production well.