Method and apparatus for transmitting electromagnetic waves and analyzing returns to locate underground fluid deposits

• US 6,188,221 B1
• Filed: 08/07/1998
• Issued: 02/13/2001
• Est. Priority Date: 08/07/1998
• Status: Expired due to Term

• Current Assignee: Andrew R. Van De Kop, Bridget M. Van De Kop, Franz Van De Kop
• Original Assignee: Andrew R. Van De Kop, Bridget M. Van De Kop, Franz Van De Kop
• Inventors: Van de Kop, Franz, Van de Kop, Andrew R., Van de Kop, Bridget M.
• Primary Examiner(s): PATIDAR, JAY M
• Application Number:
  US09/130,778
• Time in Patent Office: 921 Days
• Field of Search: 324/337-342, 324/334, 324/329, 342/22, 342/27, 342/82, 342/88, 342/371
• US Class Current: 324/337
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005

Abstract

An electromagnetic (EM) survey system for determining the presence of liquid or gaseous deposits within the earth'"'"'s interior. The system includes an EM pulse generator for generating the EM pulses, a data acquisition system for receiving and processing reflected signals from the earth'"'"'s interior caused by the EM pulses, and a data processing system for analyzing the reflected signals to determine the presence of fluids in the earth'"'"'s interior. Delivery of the EM pulses to the earth'"'"'s interior can be accomplished either invasively or non-invasively. In an invasive manner, the EM pulse is delivered to the earth'"'"'s interior via a set of electrodes buried shallow into the ground. In a non-invasive coupling, the EM pulse is delivered to the earth'"'"'s interior via a wire loop. The reflected signals are received from the earth'"'"'s interior via one of a wire loop, set of electrodes, wire antenna, or rod antenna array.

Claims

1. An apparatus, comprising:

an electromagnetic pulse generator for generating a plurality of electromagnetic pulses, said electromagnetic pulse generator includes;

an energy storage device for storing a voltage supplied from an external source;

a sparkgap switch, coupled to said energy storage device, for generating said electromagnetic pulses when a predetermined threshold voltage of said energy storage device is achieved; and

a matching network, coupled to said sparkgap switch, for passing said electromagnetic pulses to said transmit ground coupling device;

a transmit ground coupling transducer, coupled to said pulse generator, for delivering said electromagnetic pulses to the earth'"'"'s interior;

a data acquisition system for processing a plurality of reflected signals, said reflected signals being said electromagnetic pulses reflected from the earth'"'"'s interior;

a receive ground coupling transducer, coupled to said data acquisition system, for receiving and supplying said reflected signals to said data acquisition system; and

a data processing system, coupled to said data acquisition system, for comparing said reflected signals to determine the existence of fluids in the earth'"'"'s interior.

2. The apparatus of claim 1, wherein said electromagnetic pulse generator further comprises:

a current monitor for monitoring the pulse waveform of said electromagnetic pulses for subsequent comparison with said reflected signals.

3. The apparatus of claim 1, wherein said electromagnetic pulses generator further comprises:

a control unit for controlling said electromagnetic pulse generator;

a power supply, coupled to said control unit and said external source, for supplying power to said electromagnetic pulse generator; and

a current limiter, coupled to said power supply and said energy storage device, for limiting the current output from said power supply.

4. The apparatus of claim 1, wherein said transmit ground coupling transducer comprises one selected from a group of:

at least one electrode; and

a wire loop.

5. The apparatus of claim 1, wherein said energy storage device comprises one selected from a group of:

a capacitor bank; and

a delay line.

6. The apparatus of claim 5, wherein said capacitor bank comprises:

a plurality of capacitors coupled in parallel.

7. The apparatus of claim 5, wherein said delay line comprises:

a plurality of stages, wherein each respective stage includes two capacitors and an inductor.

8. The apparatus of claim 1, wherein said receive ground coupling;

transducer comprises one selected from a group of;

at least one electrode;

a wire loop;

a wire antenna; and

a rod antenna array.

9. The apparatus of claim 1, wherein said data acquisition system further comprises:

a receiver module, including;

a logarithmic channel for amplifying said one or more reflected signals;

a linear channel for amplifying said one or more reflected signals; and

a switch for activating either said logarithmic channel or said linear channel to receive said one or more reflected signals.

10. The apparatus of claim 9, wherein said logarithmic channel further comprises:

a filter, a pre-amplifier, a logarithmic amplifier, and a line driver for conditioning said one or more reflected signals.

11. The apparatus of claim 9, wherein said linear channel further comprises:

a filter, a pre-amplifier, a linear amplifier, a time variable gain circuit, and a dual-line driver for conditioning said one or more reflected signals.

12. The apparatus of claim 9, wherein the data acquisition system further comprises:

a digital recording system, including;

an analog-to-digital converter for converting said reflected signals to digital signals received from said receiver module; and

a computer module for receiving and processing said digital signals.

13. A method for determining the presence of fluids within the earth'"'"'s interior, comprising:

generating a series of electromagnetic pulses into the earth'"'"'s interior, said generating comprises;

storing a voltage in an energy storage device; and

generating said series of electromagnetic pulses when said voltage in said energy storage device reaches a predetermined threshold;

receiving a series of reflected signals from the earth'"'"'s interior, said reflected signals being said electromagnetic pulses reflected from the earth'"'"'s interior;

passing said series of reflected signals through a filtering and amplification channel;

converting said amplified reflected signals to digital signals; and

comparing said reflected signals to determine the presence of a fluid within the earth'"'"'s interior.

14. The method of claim 13, wherein said generating further comprises:

transmitting said series of electromagnetic pulses to the earth'"'"'s interior via a wire loop or a set of ground electrodes.

15. The method of claim 13, wherein said receiving further comprises:

receiving said series of reflected signals from the earth'"'"'s interior via a wire loop, a set of ground electrodes, a wire antenna, or a rod antenna array.

16. The method of claim 13, wherein said comparing further comprises:

determining for the presence of uncorrelated amplitude and phase charges in said received series of reflected signals.

17. An apparatus, comprising:

means for generating a plurality of electromagnetic pulses, said generating means comprises;

an energy storage device for storing a voltage supplied from an external source;

a sparkgap switch, coupled to said energy storage device, for generating said electromagnetic pulses when a predetermined threshold voltage of said energy storage device is achieved; and

a matching network, coupled to said sparkgap switch, for passing said electromagnetic pulses to said transmit ground coupling device;

means for delivering electromagnetic pulses generated by said pulse generating means to the earth'"'"'s interior;

means for processing a plurality of reflected signals, said reflected signals being electromagnetic pulses delivered by said delivering means and reflected from the earth'"'"'s interior;

means for receiving and supplying reflected signals to said processing means; and

means for comparing received reflected signals to determine the presence of fluids in the earth'"'"'s interior.

18. The apparatus of claim 17, wherein said means for generating a plurality of electromagnetic pulses further comprises:

a current monitor for monitoring the pulse waveform of said electromagnetic pulses for subsequent comparison with said reflected signals.

19. The apparatus of claim 17, wherein said means for generating a plurality of electromagnetic pulses further comprises:

a control unit for controlling said means for generating a plurality of electromagnetic pulses;

a power supply, coupled to said control unit and said external source, for supplying power to said means for generating a plurality of electromagnetic pulses; and

a current limiter, coupled to said power supply and said energy storage device, for limiting the current output from said power supply.

20. The apparatus of claim 17, wherein said means for delivering comprises one selected from a group of:

at least one electrode; and

a wire loop.

21. The apparatus of claim 17, wherein said energy storage device comprises one selected from a group of:

a capacitor bank; and

a delay line.

22. The apparatus of claim 21, wherein said capacitor bank comprises:

a plurality of capacitors coupled in parallel.

23. The apparatus of claim 21, wherein said delay line comprises:

a plurality of stages, wherein each respective stage includes two capacitors and an inductor.

24. The apparatus of claim 17, wherein said means for receiving comprises one selected from a group of:

at least one electrode;

a wire loop;

a wire antenna; and

a rod antenna array.

25. The apparatus of claim 17, wherein said processing means further comprises:

a receiver module, including;

a logarithmic channel for amplifying said one or more reflected signals;

a linear channel for amplifying said one or more reflected signals; and

a switch for activating either said logarithmic channel or said linear channel to receive said one or more reflected signals.

26. The apparatus of claim 25, wherein said logarithmic channel further comprises:

a filter, a pre-amplifier, a logarithmic amplifier, and a line driver for conditioning said one or more reflected signals.

27. The apparatus of claim 25, wherein said linear channel further comprises:

a filter, a pre-amplifier, a linear amplifier, a time variable gain circuit, and a dual-line driver for conditioning said one or more reflected signals.

28. The apparatus of claim 25, wherein the processing means further comprises:

a digital recording system, including;

an analog-to-digital converter for converting said reflected signals to digital signals received from said receiver module; and

a computer module for receiving and processing said digital signals.