Downhole fluid characterization methods employing a casing with a multi-electrode configuration

Patent metadata

Field	Value
Publication number	US-10914159-B2
Application number	US-201515536090-A
Country	US
Kind code	B2
Filing date	Feb 13, 2015
Priority date	Feb 13, 2015
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A method that includes deploying a casing with a multi-electrode configuration over a dielectric layer in a downhole environment. The method also includes collecting electromagnetic (EM) measurements using the multi-electrode configuration, and processing the EM measurements to obtain a characterization of fluids in an annulus between the casing and a borehole wall. A related system includes a casing deployed downhole, the casing having a multi-electrode configuration and a dielectric layer between the casing and the multi-electrode configuration. The system also includes a controller for directing collection of EM measurements using the multi-electrode configuration, and a processor that processes the EM measurements to obtain a characterization of fluids in an annulus between the casing and a borehole wall.

First claim

What is claimed is:

1. A method comprising:
deploying a casing with a multi-electrode configuration in a downhole environment, the multi-electrode configuration comprising:
electrodes attached to a dielectric material, each electrode comprising a loop antenna disposed on an outer surface of the casing, wherein each loop antenna is substantially circular and includes a gap, wherein the gaps of the loop antennas are oriented in the same direction;
a ground plane; and
an electrically-isolating protective spacer;
wherein the electrodes and the dielectric material are positioned between the ground plane and the electrically-isolating protective spacer;

collecting electromagnetic (EM) measurements using the multi-electrode configuration; and
processing the EM measurements to obtain a characterization of fluids in an annulus between the casing and a borehole wall.

2. The method of claim 1 , wherein said collecting EM measurements is performed using multiple electrode pairs, each of the pairs having a different inter-electrode spacing.

3. The method of claim 1 , further comprising processing the EM measurements to obtain a distance from the multi-electrode configuration to the borehole wall.

4. The method of claim 1 , wherein said processing the EM measurements involves inverting the EM measurements to obtain parameters of a multi-layer model.

5. The method of claim 4 , wherein said parameters comprise at least one of a dielectric constant and a conductivity for each layer of the multi-layer model.

6. The method of claim 4 , further comprising processing the EM measurements to identify a boundary of the multi-layer model that represents the borehole wall.

7. The method of claim 1 , further comprising displaying a representation of layer thickness for at least one fluid in the annulus as a function of time based on said characterization.

8. The method of claim 1 , wherein said collecting EM measurements comprises collecting EM measurements corresponding to a plurality of different frequencies.

9. The method of claim 1 , further comprising adjusting a cementing operation based on the characterization.

10. The method of claim 1 , further comprising providing power and telemetry for the multi-electrode configuration via wired pipes or via a wire deployed in the annulus.

11. The method of claim 1 , further comprising identifying three or more layers of fluids.

12. The method of claim 1 , wherein the electrodes comprise gold or copper, wherein the electrodes have the same width as the dielectric material.

Assignees

• Halliburton Energy Services Inc

Inventors

• Roberson Mark
• Goodwin Scott

Classifications

• E21B47/01

  Devices for supporting measuring instruments on drill bits, pipes, rods or wirelines; Protecting measuring instruments in boreholes against heat, shock, pressure or the like · CPC title

• E21B49/087 Primary

  Well testing, e.g. testing for reservoir productivity or formation parameters · CPC title

• E21B47/12

  Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling · CPC title

• G01V3/38

  Processing data, e.g. for analysis, for interpretation, for correction · CPC title

• G01V3/34

  Transmitting data to recording or processing apparatus; Recording data · CPC title