System for geophysical prospecting using induced electrokinetic effect

• US 20060153004A1
• Filed: 11/18/2005
• Published: 07/13/2006
• Est. Priority Date: 02/04/2004
• Status: Active Grant

• Current Assignee: Seismic Sciences, Inc.
• Original Assignee: Seismic Sciences, Inc.
• Inventors: Berg, Andrey
• Granted Patent: US 7,245,560 B2
• Time in Patent Office: Days
• US Class Current: 367/37
• CPC Class Codes: G01V 1/00 Seismology; Seismic or acoustic prospecting or detecting
• CPC Class Codes: G01V 11/00 Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00
• CPC Class Codes: G01V 11/007 using the seismo-electric effect
• CPC Class Codes: G01V 2210/6163 Electromagnetic
• CPC Class Codes: G01V 3/265 Operating with fields produced by spontaneous potentials, e.g. electrochemicals or produced by telluric currents

Abstract

Methods are disclosed employing seismic waves having infrasonic frequencies in the range of about 0.1-20 Hz for generating electromagnetic waves of similar infrasonic frequency in hydrocarbon bearing subterranean formations located at depths up to about 5000 meters, said electromagnetic waves having sufficient voltage amplitudes for detection at the earth'"'"'s surface. Also disclosed are seismic sources capable of generating infrasonic seismic waves of sufficient amplitude for generating electromagnetic waves in hydrocarbon bearing formations at depths up to 5000 meters, said electromagnetic waves having voltage amplitudes sufficient for detection at the earth'"'"'s surface.

Claims

1. -18. (canceled)

19. An acoustic source for infrasonic electromagnetic wave exploration comprising:

an electrically conductive, generally cylindrical tubular member for containing an electrically conductive fluid, said tubular member having a closed top end, an open bottom end, an interior wall and an internal diameter;

an electrode axially positioned within the tubular member;

means for electrically connecting the electrode to the negative electrical pole of an external source of DC electric power; and

means for electrically connecting the tubular member to one of;

a positive electrical pole of the external source of DC electric power;

an electrical ground; and

a combination of the above.

20. The acoustic source of claim 19, including:

said tubular member having an internal diameter equivalent to about 3 times the diameter of a plasma sock created in the conductive fluid upon discharge of DC electrical power from the electrode through the conductive fluid, to the inner wall of the tubular member; and

said electrode axially positioned within the tubular member at a distance equivalent to about 3 time the internal diameter of the tubular member form the tubular member open bottom.

21. The acoustic source of claim 20, including:

the electrode having a sharpened tip for increasing the electrical energy density at the electrode tip upon discharge of DC electrical power form the electrode, through the conductive fluid to tubular member internal wall.

22. The acoustic source of claim 20, including:

the conductive fluid selected form the group consisting of salt water and brine containing at least about 3 grams per litre of dissolved inorganic salts.

23. The acoustic source of claim 22, including:

the conductive fluid comprising salt water from a body of water in which the acoustic source is positioned.

24. The acoustic source of claim 23, including:

the tubular member in contact with the body of water comprising said means for connecting the tubular member to the electrical ground.

25. The acoustic source of claim 20, including:

said means for the electrode to the negative electrical pole of the external source of DC electric power comprising;

an opening in the upper portion of the tubular member; and

an insulated electrical conductor passing through the opening in the upper portion of the tubular member and having a first end for electrical connection to the electrode and a second end for electrical connection to the negative pole of the external DC electrical power source.

26. The acoustic source of claim 20, including:

a resilient cover for closing the tubular member bottom opening and retaining the conductive fluid within the tubular member without substantially attenuating acoustic waves generated upon the discharge of electric power from the electrode, through the conductive fluid to tubular member inner wall.