Basal Planer Gravity Drainage

Abstract

Systems and methods are provided for producing hydrocarbons from reservoirs. A provided method includes drilling a first horizontal well substantially proximate to a base of a reservoir and drilling a second horizontal well at a horizontal offset from the first horizontal well. Fluid communication is established between the first horizontal well and the second horizontal well through cyclic production processes. A mobilizing fluid is injected through the second horizontal well and fluids are produced from the first horizontal well.

1 . A method for harvesting resources in a reservoir, comprising:
 drilling a first horizontal well substantially proximate to a base of a reservoir;   drilling a second horizontal well at a horizontal offset from the first horizontal well,   establishing fluid communication between the first horizontal well and the second horizontal well through a cyclic production process;   injecting a mobilizing fluid through the second horizontal well; and   producing fluids from the first horizontal well.   
     
     
         2 . The method of  claim 1 , wherein the horizontal offset is between about 50 and 200 metres. 
     
     
         3 . The method of  claim 1 , wherein the second horizontal well is greater than about three metres shallower than the first well. 
     
     
         4 . The method of  claim 1 , comprising equalizing pressure on the reservoir by conditioning. 
     
     
         5 . The method of  claim 1 , comprising completing the second horizontal well with limited entry perforations (LEPs) configured to evenly distribute a steam injection. 
     
     
         6 . The method of  claim 5 , wherein the limited entry perforations (LEPs) are spaced at distances less than half of a distance between the first well and the second well. 
     
     
         7 . The method of  claim 1 , comprising completing the first horizontal well with limited entry perforations (LEPs) configured to provide a substantially even production of fluids. 
     
     
         8 . The method of  claim 7 , wherein the limited entry perforations (LEPs) are spaced at distances less than half of a distance between the first well and the second well. 
     
     
         9 . The method of  claim 1 , comprising establishing fluid communication between the first horizontal well and the second horizontal well by creating solvent fingers using cyclic solvent injection and production. 
     
     
         10 . The method of  claim 1 , wherein establishing fluid communication is performed by cyclic steam stimulation, cyclic solvent stimulation, or both. 
     
     
         11 . The method of  claim 1 , wherein injecting a mobilizing fluid comprises steam injection, solvent injection, or a mixed injection. 
     
     
         12 . The method of  claim 1 , comprising raising the pressure in the reservoir to create horizontal fractures. 
     
     
         13 . A system for harvesting resources in a reservoir, comprising:
 a first horizontal well substantially proximate to the base of the reservoir;   a second horizontal well at a horizontal offset from the first horizontal well, wherein the second horizontal well is vertically offset from the first horizontal well;   a cyclic production system configured to establish fluid communication between the wells; and   a continuous injection and production system configured to inject a mobilizing fluid into the second horizontal well and produce a fluid from the first horizontal well.   
     
     
         14 . The system of  claim 13 , comprising a steam generation system configured to provide steam for injection. 
     
     
         15 . The system of  claim 13 , comprising a separation system configured to separate a hydrocarbon stream from a produced fluid. 
     
     
         16 . The system of  claim 13 , comprising a geologic model configured to locate the base of the reservoir. 
     
     
         17 . A method for producing hydrocarbons, comprising:
 producing fluids from a plurality of production wells in a reservoir, wherein each of the production wells are located substantially proximate to the base of the reservoir;   injecting mobilizing fluids into the reservoir through a plurality of injection wells, wherein:
 each of the plurality of injection wells is adjacent to one of the plurality of production wells; 
 each of the plurality of injection wells is laterally offset from each of the adjacent production wells; and 
 fluid communication has been established between an injection well and an adjacent production well using a cyclic production process; and 
 separating a hydrocarbon stream from the fluids produced from the plurality of production wells. 
   
     
     
         18 . The method of  claim 17 , wherein each of the plurality of injection wells is drilled at a shallower level than each of the adjacent production wells. 
     
     
         19 . The method of  claim 17 , wherein the lateral offset is between about 50 and 200 metres, and each of the plurality of injection wells is at least about three metres higher than a neighbouring production well. 
     
     
         20 . The method of  claim 17 , comprising completing each of the plurality of production wells with a limited entry perforation screen configured to reduce the entry of vapour into the production well.