Abstract: The disclosure describes an electromagnetic apparatus, and a method of use thereof, for simultaneously generating near-uniform heating in a subsurface formation and simultaneously recovering organic and inorganic materials through the apparatus itself. The apparatus may be constructed from flexible or semi-rigid materials for use in horizontal borehole applications. The disclosure also describes a phase-modulated multiple borehole system, and a method of use thereof, for heating larger subsurface volumes and for creating steerable and variable heating patterns. The apparatus and system described herein may be used for recovering oil trapped in rock formations and for decontaminating a region of the earth contaminated with hazardous materials.

Abstract: A microwave catheter system used for heating arterial plaque and including a catheter member adapted for positioning in the artery and an inflatable balloon supported at the distal end of the catheter member. Microwave energy is coupled by means of a transmission line to an antenna means. An optic fiber extends through the catheter member and may be used for temperature sensing or other purposes. A channel is provided through the catheter member for coupling a fluid to the balloon for inflation thereof.

Abstract: A microwave collinear antenna array applicator for in situ or in vivo treatment of tumors and/or other materials by hyperthermia is disclosed. The array consists of a plurality of harmonically related resonant coaxial antenna elements connected electrically in series to provide uniform heating along the entire length of the array. At the distal end of the array, a resistor may be provided at the inner conductor for steering the heating pattern. At the proximal end of the array, an impedance matching dielectric structure is provided to enable maximum power transfer to the array and to minimize stray leakage currents along the outside of the coaxial transmission line. The array may be made longer or shorter without changing frequency and therefore, depth of penetration by simply adding or subtracting half-wave resonant elements or sections of coaxial transmission line. A lossy sleeve member may be provided around the applicator to provide a localized source of heat.

Abstract: A microwave collinear antenna array applicator for in situ or in vivo treatment of tumors and/or other materials by hyperthermia is disclosed. The array consists of a plurality of harmonically related resonant coaxial antenna elements connected electrically in series to provide uniform heating along the entire length of the array. At the distal end of the array, a resistor may be provided at the inner conductor for steering the heating pattern. At the proximal end of the array, an impedance matching dielectric structure is provided to enable maximum power transfer to the array and to minimize stray leakage currents along the outside of the coaxial transmission line. The array may be made longer or shorter without changing frequency and therefore depth of penetration by simply adding or subtracting half-wave resonant elements or sections of coaxial transmission line. A lossy sleeve member may be provided around the applicator to provide a localized source of heat.

Abstract: A microwave dipole probe for in vivo localized hyperthermia includes an outer conductor and an inner conductor extending through and beyond the outer conductor. The portion of the inner conductor extending beyond the outer conductor is expanded in diameter relative to the portion within the outer conductor. A dielectrically loaded phase reversal sleeve is folded over the outside of the outer conductor and contains a dielectric loading material similar to the dielectric constant of the in vivo target volume.

Abstract: A system for in situ heating of oil shale by radiating electromagnetic wave energy from a dipole radiator positioned beneath an overburden in a body of oil shale. Radio frequency power is supplied from the surface through a transmission line to the radiator dipoles whose diameters are substantially greater than the spacing between the transmission line conductors. The dipole radiator is center fed by the transmission line through a reentrant choke structure substantially filled with a solid dielectric medium and concentric with one of said dipole elements.

Abstract: The process and apparatus for extracting the products of kerogen in situ from an oil shale body by supplying energy selectively to the kerogen by high frequency electric fields in the frequency range between 100 kilohertz and 1000 megahertz at an intensity which heats the kerogen to a temperature range between 250.degree. C. and 500.degree. C. to allow pyrolysis of the kerogen prior to substantial heat transfer to the surrounding mineral portions of the oil shale. A plurality of groups of spaced radiators produce the electric fields for heating the kerogen. A dipole radiator in the subsurface formation is supplied with electromagnetic energy through a transmission line from an energy generator on the surface.

Abstract: The process and apparatus for extracting the products of kerogen in situ from an oil shale body by supplying energy selectively to the kerogen by high frequency electric fields in the frequency range between 100 kilohertz and 1000 megahertz at an intensity which heats the kerogen to a temperature range between 250.degree. C. and 500.degree. C. to allow pyrolysis of the kerogen prior to substantial heat transfer to the surrounding mineral portions of the oil shale.

Abstract: The process and apparatus for extracting the products of kerogen in situ from an oil shale body by supplying energy selectively to the kerogen by high frequency electric fields in the frequency range between 100 kilohertz and 1000 megahertz at an intensity which heats the kerogen to a temperature range between 250.degree. C. and 500.degree. C. to allow pyrolysis of the kerogen prior to substantial heat transfer to the surrounding mineral portions of the oil shale.