Abstract: Performing steam drive operations in critical manipulative steps can improve the recovery of viscous hydrocarbons from tar sand deposits. Steam is injected into an injection well at a rate that is less than the rate needed to fracture the formation, and fluids are simultaneously produced from a communicating production well. When steam breakthrough occurs at the production well, the production well is shut-in, and the injection rate is increased to a rate at least sufficient to fracture the formation. After the reservoir is sufficiently heated, injection ceases and production resumes. Once the production rate declines to a rate that is no longer efficient, the process can be repeated.

Abstract: A multi-phase heated fluid process which avoids heated fluid breakthrough, is used to continually produce subsurface hydrocarbons, utilizing two commmunicating wells in a process comprising:Simultaneous injection of said heated fluid into said wells until substantial mobilization of hydrocarbons within a zone surrounding said wells is obtained; one well is shut in while production is commenced in the other well;Preferably a final phase where sufficient heated fluid at relatively restricted rates is continually injected into said one well to provide driving force for continual production in said other well, without interruption, once production has commenced.