Well logging sonde including a linear particle accelerator

A method of logging the media surrounding a borehole that traverses an earth formation, comprising the steps of:

• repetitively producing bursts of charged particles;
• accelerating said charged particles to high energy levels in a number of individual accelerating cavities;
• controlling the production of said bursts of charged particles in response to variations of the intensity of the bursts of accelerated particles;
• bombarding a target with the accelerated particles to emit nuclear radiation that penetrates the surrounding media;
• and
• detecting nuclear radiation returning to the borehole as a result of the interaction of the emitted radiation and the surrounding media.

A method of logging the media surrounding a bore-hole that traverses an earth formation comprising the steps of:

• accelerating charged particles to high energy levels in a number of individual accelerating cavities;
• controlling the acceleration of said particles in response to variations of at least one condition of said cavities;
• bombarding a first target with said high energy particles to emit photons that penetrate the surrounding media;
• bombarding a second target with said high energy particles to emit neutrons that penetrate the surrounding media;
• and
• obtaining indications of nuclear radiation returning to the borehole as a result of the interaction of the emitted photons and neutrons with the surrounding media.

An apparatus for logging the media surrounding a borehole that traverses an earth formation comprising, within a pressure resistant housing adapted to pass through the borehole;

• means for repetitively producing bursts of charged particles;
• linear accelerator means, including a source of driving energy, for accelerating said bursts to high energy levels along a path generally parallel to the axis of the borehole;
• means for controlling said driving energy source in response to variations of at least one condition of said linear accelerator means;
• means responsive to bombardment by said high energy charged particles for repetitively emitting bursts of nuclear radiation that penetrate the surrounding media;
• and
• means for obtaining indications of nuclear radiation returning to the borehole as a result of the interaction of the emitted radiation and the surrounding media.

An apparatus for logging the media surrounding a borehole that traverses an earth formation comprising, within a pressure resistant housing adapted to pass through the borehole:

• means for repetitively producing bursts of charged particles;
• linear accelerator means, including a microwave energy driving source, for accelerating said bursts to high energy levels;
• means for sensing the variations in the temperature of said linear accelerator means;
• means for controlling the frequency of said microwave source in response to said sensing means;
• means responsive to bombardment by said high energy charged particles for repetitively emitting bursts of nuclear radiation that penetrate the surrounding media;
• and
• means for obtaining indications of nuclear radiation returning to the borehole as a result of the interaction of the emitted radiation and the surrounding media.

An apparatus for logging the media surrounding a borehole that traverses an earth formation comprising, within a pressure resistant housing adapted to pass through the borehole:

• means for repetitively producing bursts of charged particles;
• linear accelerator means, including a microwave energy driving source, for accelerating said bursts to high energy levels;
• means for sensing the variations of said microwave energy in the linear accelerator means;
• means for controlling the frequency of said microwave source in response to said sensing means;
• means responsive to bombardment by said high energy charged particles for repetitively emitting bursts of nuclear radiation that penetrate the surrounding media;
• and
• means for obtaining indications of nuclear radiation returning to the borehole as a result of the interaction of the emitted radiation and the surrounding media.

An apparatus for logging the media surrounding a borehole that traverses an earth formation comprising, within a pressure resistant housing adapted to pass through the borehole;

• means for repetitively producing bursts of charged particles;
• linear accelerator means, including a microwave energy driving source, for accelerating said bursts to high energy levels;
• means for sensing the intensity of said bursts of high energy charged particles;
• means for controlling said producing means in response to said sensing means;
• means responsive to bombardment by said high energy charged particles for repetitively emitting bursts of nuclear radiation that penetrate the surrounding media;
• and
• means for obtaining indications of nuclear radiation returning to the borehole as a result of the interaction of the emitted radiation and the surrounding media.

An apparatus for logging the media surrounding a borehole that traverses an earth formation comprising, within a pressure resistant housing adapted to pass through the borehole:

• means for repetitively producing bursts of charged particles;
• linear accelerator means, including a microwave energy driving source, for accelerating said bursts to high energy levels;
• means for synchronizing said producing means and said mircowave source;
• means for sensing the intensity of said bursts of high energy charged particles;
• means for controlling said synchronizing means in response to said sensing means;
• means responsive to bombardment by said high energy charged particles for repetitively emitting bursts of nuclear radiation that penetrate the surrounding media;
• and
• means for obtaining indications of nuclear radiation returning of the borehole as a result of the interaction of the emitted radiation and the surrounding media.