Abstract: The invention is a well pattern containing at least one substantially horizontal production well approximately located on and parallel to an axis running between two substantially vertical production wells with the horizontal well having a length equal to about 30% to about 60% of the distance between the two vertical production wells.

Abstract: A procedure is described for producing hydrocarbons from hydrocarbon-bearing formations including shale oil from an oil shale body wherein combinations of vertical and slant holes are drilled into the shale body, and an alternating sequence of fracturing and production by in situ combustion is performed between those holes.

Abstract: A method for cleaning a helical spring screen deep in a well while filtering liquid comprises (1) injecting a high pressure hydraulic surge pulse into the spring screen for expanding the coils, (2) forcing high pressure liquid between the coils of the helical spring screen simultaneously with expanding of the coils for washing the sand from between the coils, and (3) forcing the coils together following their expansion by expanding action of a second spring for crushing and dislodging any sand therebetween the coils for removal upon subsequent spreading of the coils. A second method is disclosed likewise. Thus the methods provide for the spring coils being cleaned for a multiplicity of times without having to shut the well in for workover, thus saving workover costs and lost production.

Abstract: A method for cleaning a helical spring screen deep in a well while filtering liquid comprises (1) injecting a high pressure hydraulic surge pulse into the spring screen for expanding the coils, (2) forcing high pressure liquid between the coils of the helical spring screen simultaneously with expanding of the coils for washing the sand from between the coils, and (3) forcing the coils together following their expansion by expanding action of a second spring for crushing and dislodging any sand therebetween the coils for removal upon subsequent spreading of the coils. A second method is disclosed likewise. Methods for forming a self-cleaning helical spring screen and two modifications of a helical spring screen are disclosed herein for being cleaned for a multiplicity of times without having to shut the well in for workover, thus saving workover costs and lost production.

Abstract: A method for operating an in situ combustion process in a petroleum containing reservoir wherein a plurality of air injection wells are spaced so that the approximate distance between the wells will be twice the distance at which the flux of air to the burning front from a single injection well becomes negligible.