Tar sand production using thermal stimulation

Method and apparatus for recovering hydrocarbons from a subterranean formation in which a well completion, including a well liner, lies in a generally horizontal disposition within the hydrocarbon producing layer. The liner encloses conduit means for delivering a stream of a hot stimulating agent to the well's remote or injection end, and means for regulating the production of bitumen emulsion from the production end. A fluid impervious barrier is carried on and depends from the conductor means and forms a transverse fluid barrier within the liner. The conductor member is fixed within the liner whereby to serve as a means for introducing the thermal stimulating agent or medium to the substrate as well as functioning as a guide for the movable fluid impervious barrier. By adjusting the longitudinal position of said barrier, the hot stimulating agent is more effectively introduced to the substrate to improve the sweeping action thereof.