Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing a producer well, which defines a longitudinal axis, between at least a first and second transmission line conductor. At a reference location along the length of the longitudinal axis, the first and second transmission line conductors are laterally spaced from the producer well by a first and second reference distance, respectively. At a second location, the first and second transmission line conductors are laterally spaced from the producer well by a third and fourth distance, respectively. At least one of the third and fourth distances are greater than the first and second reference distances, respectively. Excitation of the transmission line conductors generates an electromagnetic field having a reference shape and a reference position at the reference location and at least one of a more elongated shape and a different position at the second location.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The apparatus includes an electrical power source; at least one electromagnetic wave generator for generating alternating current; at least two transmission line conductors positioned in the hydrocarbon formation; at least one waveguide for carrying the alternating current from the at least one electromagnetic wave generator to the at least two transmission line conductors; and a producer well to receive heated hydrocarbons from the hydrocarbon formation. The transmission line conductors are excitable by the alternating current to propagate a travelling wave within the hydrocarbon formation. At least one of the transmission line conductors include a primary arm and at least one secondary arm extending laterally from the primary arm. The at least one secondary arm includes at least one electrically isolatable connection for electrically isolating at least a portion of the secondary arm.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing a producer well, which defines a longitudinal axis, between at least a first and second transmission line conductor. At a reference location along the length of the longitudinal axis, the first and second transmission line conductors are laterally spaced from the producer well by a first and second reference distance, respectively. At a second location, the first and second transmission line conductors are laterally spaced from the producer well by a third and fourth distance, respectively. At least one of the third and fourth distances are greater than the first and second reference distances, respectively. Excitation of the transmission line conductors generates an electromagnetic field having a reference shape and a reference position at the reference location and at least one of a more elongated shape and a different position at the second location.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The apparatus includes an electrical power source; at least one electromagnetic wave generator for generating alternating current; at least two transmission line conductors positioned in the hydrocarbon formation; at least one waveguide for carrying the alternating current from the at least one electromagnetic wave generator to the at least two transmission line conductors; and a producer well to receive heated hydrocarbons from the hydrocarbon formation. The transmission line conductors are excitable by the alternating current to propagate a travelling wave within the hydrocarbon formation. At least one of the transmission line conductors include a primary arm and at least one secondary arm extending laterally from the primary arm. The at least one secondary arm includes at least one electrically isolatable connection for electrically isolating at least a portion of the secondary arm.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: An apparatus for a coaxial transmission line is provided. The apparatus can include a dielectric member having an inner surface defining a bore along a longitudinal axis of an inner conductor of the coaxial transmission line; and a first conductive member mounted axially around the dielectric member and extending along the longitudinal axis. A cross-section of an outer surface of the first conductive member can define a first perimeter. A cross-section of an inner surface of the outer conductor of the coaxial transmission line can define a second perimeter. The first perimeter can be smaller than the second perimeter and thereby provide clearance between a portion of the outer surface of the first conductive member and the inner surface of the outer conductor of the coaxial transmission line when the apparatus is positioned in an annulus defined by the inner conductor and the outer conductor of the coaxial transmission line.

Abstract: An apparatus for a coaxial transmission line is provided. The apparatus can include a dielectric member having an inner surface defining a bore along a longitudinal axis of an inner conductor of the coaxial transmission line; and a first conductive member mounted axially around the dielectric member and extending along the longitudinal axis. A cross-section of an outer surface of the first conductive member can define a first perimeter. A cross-section of an inner surface of the outer conductor of the coaxial transmission line can define a second perimeter. The first perimeter can be smaller than the second perimeter and thereby provide clearance between a portion of the outer surface of the first conductive member and the inner surface of the outer conductor of the coaxial transmission line when the apparatus is positioned in an annulus defined by the inner conductor and the outer conductor of the coaxial transmission line.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The apparatus includes an electrical power source; at least one electromagnetic wave generator for generating alternating current; at least two transmission line conductors positioned in the hydrocarbon formation; at least one waveguide for carrying the alternating current from the at least one electromagnetic wave generator to the at least two transmission line conductors; and a producer well to receive heated hydrocarbons from the hydrocarbon formation. The transmission line conductors are excitable by the alternating current to propagate a travelling wave within the hydrocarbon formation. At least one of the transmission line conductors include a primary arm and at least one secondary arm extending laterally from the primary arm. The at least one secondary arm includes at least one electrically isolatable connection for electrically isolating at least a portion of the secondary arm.

Abstract: An apparatus for a coaxial transmission line is provided. The apparatus can include a dielectric member having an inner surface defining a bore along a longitudinal axis of an inner conductor of the coaxial transmission line; and a first conductive member mounted axially around the dielectric member and extending along the longitudinal axis. A cross-section of an outer surface of the first conductive member can define a first perimeter. A cross-section of an inner surface of the outer conductor of the coaxial transmission line can define a second perimeter. The first perimeter can be smaller than the second perimeter and thereby provide clearance between a portion of the outer surface of the first conductive member and the inner surface of the outer conductor of the coaxial transmission line when the apparatus is positioned in an annulus defined by the inner conductor and the outer conductor of the coaxial transmission line.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: A method of making a subsurface antenna which has an assymetric radiation pattern. The assymetric radiation pattern radiates electromagnetic waves unequally into two regions.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing a producer well, which defines a longitudinal axis, between at least a first and second transmission line conductor. At a reference location along the length of the longitudinal axis, the first and second transmission line conductors are laterally spaced from the producer well by a first and second reference distance, respectively. At a second location, the first and second transmission line conductors are laterally spaced from the producer well by a third and fourth distance, respectively. At least one of the third and fourth distances are greater than the first and second reference distances, respectively. Excitation of the transmission line conductors generates an electromagnetic field having a reference shape and a reference position at the reference location and at least one of a more elongated shape and a different position at the second location.

Abstract: An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors.

Abstract: A radio frequency antenna for radiating electromagnetic energy into a reservoir filled with a target material, the antenna being operatively connected to a feed transmission line. The antenna includes a waveguide, at least one slot formed in the outer waveguide layer, and a sleeve portion enclosing at least a portion of the waveguide. The sleeve portion comprises at least first and second dielectric layers where the permittivity of the second dielectric layer is higher than the permittivity of the first dielectric layer and the first dielectric layer is positioned in closer proximity to the waveguide than the second dielectric layer. When the antenna is inserted into the reservoir, the input impedance of the antenna remains matched to the feed transmission line for a wide range of target materials.

Abstract: A radio frequency antenna for radiating electromagnetic energy into a reservoir filled with a target material, the antenna being operatively connected to a feed transmission line. The antenna includes a waveguide, at least one slot formed in the outer waveguide layer, and a sleeve portion enclosing at least a portion of the waveguide. The sleeve portion comprises at least first and second dielectric layers where the permittivity of the second dielectric layer is higher than the permittivity of the first dielectric layer and the first dielectric layer is positioned in closer proximity to the waveguide than the second dielectric layer. When the antenna is inserted into the reservoir, the input impedance of the antenna remains matched to the feed transmission line for a wide range of target materials.

Abstract: A subsurface antenna is designed for use below the surface of the Earth. In some configurations the antenna is a dipole antenna, which can be used for radio frequency heating of an oil-bearing formation.