| 摘要 |
<p>METHOD FOR RECOVERING HEAVY CRUDES FROM SHALLOW RESERVOIRS This invention provides in the production of heavy oil from a shallow subterranean tar sand bed penetrated by spaced injection and recovery systems, the method comprising: (a) forming a plurality of horizontal fractures spanning the distance between said injection system and said recovery system, said fractures being spaced apart in a vertical direction with respect to each other throughout the depth of the tar sand bed; (b) injecting a solvent for heavy oil into said fractures via said injection system, (c) shutting in the injection and recovery systems for a predetermined period of time to form a heavy oil/solvent mixture of reduced viscosity by gravity-driven convective mixing, and (d) recovering said heavy oil/solvent mixture in said recovery system by conventional recovery techniques.</p> |
