3620300 is referenced by 69 patents and cites 11 patents.

A method and apparatus include providing one or more vertically spaced electrodes in the borehole in electrical contact with the formation. Two electrodes in a common borehole may be connected to a surface source of alternating current voltage to conductive paths provided respectively by a conductive casing and a conductive tubing suitably insulated from each other; or the two electrodes connected to the voltage source may be placed in separate adjacent boreholes. The flow of current through the formation is guided or directed by means of insulating barriers which extend laterally into the formation from the borehole in vertically spaced relation to the electrode.

Method and apparatus for electrically heating a subsurface formation
Application Number
Publication Number
Application Date
April 20, 1970
Publication Date
November 16, 1971
Fred L Crowson
Giles C Clegg Jr
The Electrothermic Co Corpus Christi TX
E21b 43/24
E21B 43/24
E21B 43/16
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