Monitoring of wells to detect the composition of matter in boreholes and propped fractures

• US 9,546,547 B2
• Filed: 11/23/2015
• Issued: 01/17/2017
• Est. Priority Date: 04/26/2012
• Status: Active Grant

• Current Assignee: Farrokh Mohamadi
• Original Assignee: Farrokh Mohamadi
• Inventors: Mohamadi, Farrokh
• Primary Examiner(s): Bousono, Orlando
• Application Number:
  US14/949,476
• Publication Number:
  US 20160076366A1
• Time in Patent Office: 421 Days
• US Class Current: 1/1
• CPC Class Codes: E21B 43/267 reinforcing fractures by propping
• CPC Class Codes: E21B 47/11 using tracers; using radioactivity
• CPC Class Codes: E21B 47/13 by electromagnetic energy, e.g. radio frequency
• CPC Class Codes: G01V 3/30 operating with electromagnetic waves

Abstract

There is provided a system and method for monitoring of fractured wells and conventional wells to detect leaks. The method comprises interrogating a plurality of resonant tags using a modulated RF signal transmitted from an interrogator, wherein the plurality of resonant tags are dispersed within a channel.

Claims

1. A system comprising:

a processor;

a plurality of resonant tags, wherein each resonant tag further comprises;

a cylindrical array comprising a plurality of structures arranged to form a second hollow cylinder;

a dielectric material configured to fill the second hollow cylinder; and

a binder configured to adhere the filled cylindrical array to a borehole-facing wall of a well casing of an oil well borehole such that the plurality of resonant tags are adhered to the borehole-facing wall of the well casing; and

an interrogator configured to interrogate a channel associated with the oil well borehole between the interrogator and the plurality of resonant tags adhered to the borehole-facing wall using a frequency-modulated radio frequency (RF) signal such that the frequency-modulated RF signal covers an expected range of resonant frequencies for the plurality of resonant tags adhered to the borehole-facing wall within the channel, and wherein the processor is configured to characterize a dielectric constant for a medium in the channel using signal strengths of resonant reflections received by the interrogator from the plurality of resonant tags adhered to the borehole-facing wall within the channel.

2. The system of claim 1, wherein the processor is further configured to determine a composition of matter filling the channel based upon the characterized dielectric constant.

3. The system of claim 1, wherein the processor is further configured to map a location for the plurality of resonant tags.

4. The system of claim 1, further comprising:

a metallic casing disposed in the oil well borehole, wherein the metallic casing is coated with a low dielectric substrate containing at least one of the plurality of resonant tags.

5. The system of claim 1, wherein at least one of the plurality of resonant tags is configured to be resonant in the terahertz region.

6. The system of claim 1, wherein the interrogator is configured to beam form the frequency-modulated RF signal.

7. The system of claim 1, wherein the interrogator is configured to beam steer the frequency-modulated RF signal.

8. A method comprising:

interrogating, using a frequency-modulated radio frequency (RF) signal transmitted from an interrogator, a channel associated with an oil well borehole between the interrogator and a plurality of resonant tags adhered to a borehole-facing wall of a well casing of the oil well borehole such that the frequency-modulated RF signal covers an expected range of resonant frequencies for the plurality of resonant tags adhered to the borehole-facing wall within the channel, wherein each resonant tag further comprises;

a cylindrical array comprising a plurality of structures arranged to form a second hollow cylinder;

a dielectric material configured to fill the second hollow cylinder; and

a binder configured to adhere the filled cylindrical array to the borehole-facing wall of the well casing of the oil well borehole such that the plurality of resonant tags are adhered to the borehole-facing wall of the well casing;

determining, using a processor, signal strengths of resonant reflections received by the interrogator from the plurality of resonant tags adhered to the borehole-facing wall within the channel; and

characterizing a dielectric constant for a medium in the channel using the determined signal strengths.

9. The method of claim 8, further comprising determining, using the processor, a composition of matter filling the channel based upon the characterized dielectric constant.

10. The method of claim 8, further comprising:

determining, using the processor, a composition of matter for a plurality of portions of the oil well borehole using the characterized dielectric constant; and

detecting, from the plurality of portions of the oil well borehole, a portion of the oil well borehole having an anomalous composition of matter compared to remaining ones of the plurality of portions of the oil well borehole.

11. A method, comprising:

advancing an interrogator through an oil well borehole to sampled locations within the oil well borehole, wherein the oil well borehole includes a well casing having a plurality of resonant tags lining a borehole-facing wall of the well casing of the oil well borehole, wherein each resonant tag further comprises;

a cylindrical array comprising a plurality of structures arranged to form a second hollow cylinder;

a dielectric material configured to fill the second hollow cylinder; and

a binder configured to adhere the filled cylindrical array to the borehole-facing wall of the well casing of the oil well borehole such that the plurality of resonant tags are adhered to the borehole-facing wall of the well casing;

at each sampled location, interrogating, using a frequency-modulated radio frequency (RF) signal transmitted from the interrogator, resonant tags at the sampled location from the plurality of resonant tags adhered to the borehole-facing wall to characterize a dielectric constant for a channel between the interrogator and the interrogated resonant tags at the sampled location such that the frequency-modulated RF signal covers an expected range of resonant frequencies for the interrogated resonant tags adhered to the borehole-facing wall within the channel by determining, using a processor, signal strengths of resonant reflections received by the interrogator from the interrogated resonant tags at the sample location; and

based upon the characterized dielectric constants at each sampled locations, determining whether the well casing is compromised.

12. The method of claim 11, wherein determining whether the well casing is compromised includes determining whether the characterized dielectric constant at each sampled location indicates the presence of water within the oil well borehole.