U.S. patent application number 17/689526 was filed with the patent office on 2022-06-23 for methods and means for the measurement of tubing, casing, perforation and sand-screen imaging using backscattered x-ray radiation in a wellbore environment.
The applicant listed for this patent is Melissa Spannuth, Alex Stewart, Philip Teague, Teresa Tutt. Invention is credited to Melissa Spannuth, Alex Stewart, Philip Teague, Teresa Tutt.
Application Number | 20220196577 17/689526 |
Document ID | / |
Family ID | |
Filed Date | 2022-06-23 |
United States Patent
Application |
20220196577 |
Kind Code |
A1 |
Teague; Philip ; et
al. |
June 23, 2022 |
Methods and Means for the Measurement of Tubing, Casing,
Perforation and Sand-Screen Imaging Using Backscattered X-Ray
Radiation in a Wellbore Environment
Abstract
An x-ray-based cased wellbore tubing and casing imaging tool is
disclosed, the tool including at least a shield to define the
output form of the produced x-rays; a two-dimensional per-pixel
collimated imaging detector array; a parallel hole collimator
format in one direction that is formed as a pinhole in another
direction; Sonde-dependent electronics; and a plurality of tool
logic electronics and PSUs. A method of using an x-ray-based cased
wellbore tubing and casing imaging tool is also disclosed, the
method including at least: producing x-rays in a shaped output;
measuring the intensity of backscatter x-rays returning from
materials surrounding a wellbore; determining an inner and an outer
diameter of tubing or casing from the backscatter x-rays; and
converting image data from said detectors into consolidated images
of the tubing or casing.
Inventors: |
Teague; Philip; (Spring,
TX) ; Spannuth; Melissa; (Houston, TX) ;
Stewart; Alex; (San Francisco, CA) ; Tutt;
Teresa; (Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Teague; Philip
Spannuth; Melissa
Stewart; Alex
Tutt; Teresa |
Spring
Houston
San Francisco
Houston |
TX
TX
CA
TX |
US
US
US
US |
|
|
Appl. No.: |
17/689526 |
Filed: |
March 8, 2022 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
16290360 |
Mar 1, 2019 |
|
|
|
17689526 |
|
|
|
|
17030970 |
Sep 24, 2020 |
|
|
|
16290360 |
|
|
|
|
16290360 |
Mar 1, 2019 |
|
|
|
17030970 |
|
|
|
|
62636907 |
Mar 1, 2018 |
|
|
|
International
Class: |
G01N 23/203 20060101
G01N023/203; G01V 5/12 20060101 G01V005/12; G01V 1/50 20060101
G01V001/50; E21B 47/002 20060101 E21B047/002; E21B 47/005 20060101
E21B047/005; E21B 47/085 20060101 E21B047/085 |
Claims
1. An x-ray-based cased wellbore tubing and casing imaging tool,
said tool comprising: a shield to define the output form of the
produced x-rays; a two-dimensional per-pixel collimated imaging
detector array; a parallel hole collimator format in one direction
that is formed as a pinhole in another direction; Sonde-dependent
electronics; and a plurality of tool logic electronics and
PSUs.
2. The tool of claim 1, wherein said imaging detector comprises a
two-dimensional per-pixel collimated imaging detector arrays,
wherein the imaging array is one pixel wide and multiple pixels
long.
3. The tool of claim 1, wherein said imaging detectors comprise two
sets of two-dimensional per-pixel collimated imaging detector
arrays.
4. The tool of claim 1, wherein said imaging detectors comprise a
plurality of two-dimensional per-pixel collimated imaging detector
arrays.
5. The tool of claim 1, wherein the images contain spectral
information to inform characteristics of any wellbore materials or
debris.
6. The tool of claim 1, wherein said shield further comprises
tungsten.
7. The tool of claim 1, wherein the tool is configured so as to
permit through-wiring.
8. The tool of claim 1, wherein the tool is combinable with other
measurement tools comprising one or more of acoustic or ultrasonic
tools.
9. The tool of claim 1, wherein the tool is used to determine an
inner diameter of a tubing or casing.
10. The tool of claim 1, wherein the tool is used to determine an
outer diameter of a tubing or casing.
11. The tool of claim 1, wherein the tool is used to determine a
distribution and inner diameter of a scale upon an inner diameter
of a tubing or casing.
12. The tool of claim 1, wherein the tool is used to determine the
position, distribution and area of perforations, within casings
surrounding a cased wellbore.
13. The tool of claim 1, wherein the tool is used to determine the
position and integrity of sand-screens, within casings surrounding
a cased wellbore.
14. The tool of claim 1, wherein the tool is used to determine the
position and integrity of gravel-packs, within casings surrounding
a cased wellbore.
15. The tool of claim 1, wherein the tool is used to determine the
position and integrity of side-pocket mandrels, within casings
surrounding a cased wellbore.
16. The tool in claim 1, wherein machine learning is employed to
automatically reformat or re-tesselate the resulting images as a
function of depth and varying logging speeds or logging steps.
17. A method of using an x-ray-based cased wellbore tubing and
casing imaging tool, said method comprising: producing x-rays in a
shaped output; measuring the intensity of backscatter x-rays
returning from materials surrounding a wellbore; determining an
inner and an outer diameter of tubing or casing from the
backscatter x-rays; and converting image data from said detectors
into consolidated images of the tubing or casing.
18. The method of claim 17, wherein said imaging detector comprises
a two-dimensional per-pixel collimated imaging detector arrays
wherein the imaging array is one pixel wide and multiple pixels
long.
19. The method of claim 17, wherein said imaging detectors comprise
two sets of two-dimensional per-pixel collimated imaging detector
arrays.
20. The method of claim 17, wherein said imaging detectors comprise
a plurality of two-dimensional per-pixel collimated imaging
detector arrays.
21. The method of claim 17, wherein the images contain spectral
information to inform the characteristics of any wellbore materials
or debris.
22. The method of claim 17, wherein the tool is combinable with
other measurement methods comprising one or more of acoustic or
ultrasonic.
23. The method of claim 17, wherein the tool is used to determine
an inner diameter of a tubing or casing.
24. The method of claim 17, wherein the tool is used to determine
an outer diameter of a tubing or casing.
25. The method of claim 17, wherein the tool is used to determine
the distribution and inner diameter of a scale upon the inner
diameter of a tubing or casing.
26. The method of claim 17, wherein the tool is used to determine
the position, distribution and area of perforations, within casings
surrounding a cased wellbore.
27. The method of claim 17, wherein the tool is used to determine
the position and integrity of sand-screens, within casings
surrounding a cased wellbore.
28. The method of claim 17, wherein the tool is used to determine
the position and integrity of gravel-packs, within casings
surrounding a cased wellbore.
29. The method of claim 17, wherein the tool is used to determine
the position and integrity of side-pocket mandrels, within casings
surrounding a cased wellbore.
30. The method of claim 17, wherein machine learning is employed to
automatically reformat or re-tesselate the resulting images as a
function of depth and varying logging speeds or logging steps.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to methods and means
for monitoring and determining tubing, casing, and sand-screen
integrity, in addition to casing perforation size, form, and
distribution.
BACKGROUND
[0002] Within the oil & gas industry, the requirement to gauge
the quality of tubing is paramount.
[0003] The industry currently employs various methods for the
verification of the quality of the casing. Typically, calipers or
cameras are employed to determine whether the casing/tubing is
cylindrical and or not-corroded. However, cameras require the
wellbore to contain optically clear fluids; otherwise they are
incapable of distinguishing features within the fluid or borehole.
More recently, ultra-sonic tools have been run within the well in
an attempt to image the casing or tubing, or elements outside of
the tubing such as the parts of a downhole safety valve. However,
ultrasonic tools are model dependent, so prior knowledge of the
precise makeup and status of the well is typically required for the
ultrasound data comparison purposes.
[0004] No viable technologies are currently available that use a
method or means to employ a combination of collimators, located
cylindrically around an X-ray source, located within a non-padded
concentrically-located borehole logging tool, together with a
plurality of three-dimensional per-pixel collimated imaging
detector array(s) to also be used as the primary imaging
detector(s), to produce complete backscatter images of the
casing/tubing, in addition to being able to accurately measure the
inner-diameter and outer-diameter of the tubing, even in the
presence of scale deposits.
[0005] Prior art teaches a variety of techniques that use x-rays or
other radiant energy to inspect or obtain information about the
structures within or surrounding the borehole of a water, oil or
gas well, yet none teach of a method to use the first order
detectors (that are typically used to compensate for mud-cake/fluid
variations) to create a photograph-like image of the casing
itself.
[0006] US20190063209 to Teague teaches an x-ray-based cement
evaluation tool for determining whether a cement bond exists
between the casing and cement of a cemented borehole, the tool
including at least: an internal length comprising a Sonde section,
wherein said Sonde section further comprises an x-ray source; a
radiation shield for radiation measuring detectors; arrayed
pixelated detectors; Sonde-dependent electronics; and a plurality
of tool logic electronics and PSUs.
[0007] US20190049621 to Teague et al teaches an x-ray based cement
evaluation tool for measurement of the density of material volumes
within single, dual and multiple-casing wellbore environments,
wherein the tool uses x-rays to illuminate the formation
surrounding a borehole, and a plurality of detectors are used to
directly measure the density of the cement annuli and any
variations in density within. The tool uses x-rays to illuminate
the casing surrounding a borehole and a plurality of multi-pixel
imaging detectors directly measures the thickness of the
casing.
[0008] US20190048709 to Teague et al teaches an x-ray-based cased
wellbore environment imaging tool, the tool including at least an
x-ray source; a radiation shield to define the output form of the
produced x-rays; a direction controllable two-dimensional per-pixel
collimated imaging detector array; Sonde-dependent electronics; and
a plurality of tool logic electronics and PSUs.
[0009] U.S. Pat. No. 7,675,029 to Teague teaches an apparatus that
permits the measurement of x-ray backscattered photons from any
horizontal surface inside of a borehole that refers to
two-dimensional imaging techniques.
[0010] U.S. Pat. No. 7,705,294 to Teague teaches an apparatus that
aims to measure backscattered x-rays from the inner layers of a
borehole in selected radial directions with the missing segment
data being populated through movement of the apparatus through the
borehole. The apparatus permits generation of data for a
two-dimensional reconstruction of the well or borehole, but the
publication does not teach of the necessary geometry for the
illuminating x-ray beam to permit discrimination of the depth from
which the backscattered photons originated, only their direction.
It also fails to teach of a method or means that can be employed to
create a helical ribbon image, or a cylindrical image while
stationary. Optimally, the tool is constantly moving so as to
recreate tessellated sections of an image, rather than an
azimuthally scanning image that is generally independent of hole
size/geometry.
[0011] U.S. Pat. No. 8,481,919 to Teague 2012 teaches a method of
producing Compton-spectrum radiation in a borehole without the use
of radioactive isotopes, and further describes rotating collimators
around a fixed source installed internally to the apparatus, but
does not have solid-state detectors with collimators. It further
teaches of the use of conical and radially symmetrical anode
arrangements to permit the production of panoramic x-ray
radiation.
[0012] U.S. Pat. No. 3,564,251 to Youmans discloses the use of a
azimuthally scanning collimated x-ray beam that is used to produce
an attenuated signal at a detector for the purposes of producing a
spiral-formed log of the inside of a casing or borehole surface
immediately surrounding the tool, effectively embodied as an x-ray
caliper. The reference, however, fails to teach of a means or
method to create a photo-like image, other than a two-dimensional
radial plot on an oscilloscope.
[0013] U.S. Pat. No. 7,634,059 to Wraight discloses a concept that
may be used to produce individual two-dimensional x-ray images of
the inner surface inside of a borehole using a single pin-hole
camera without the technical possibility to ascertain the azimuth
of the image being taken, such that a tessellation/stitching of
multiple images is not taught. In addition, it fails to provide a
method that could be used to log (i.e., actively move) the tool
axially, such that a consolidated image of the inside of the casing
may be created.
[0014] US2013/0009049 to Smaardyk discloses a concept that allows
measurement of backscattered x-rays from the inner layers of a
borehole. However, the reference fails to disclose a means or
method to create photo-like two dimensional images of the inner
surfaces of the casing, while the tool is being axially moved
(`logged`) through the wellbore, such that a consolidated two
dimensional image of the well casing can be produced.
[0015] U.S. Pat. No. 8,138,471 to Shedlock discloses a
scanning-beam apparatus based on an x-ray source, a rotatable x-ray
beam collimator and solid-state radiation detectors enabling the
imaging of only the inner surfaces of borehole casings and
pipelines. However, the reference fails to teach or suggest a means
or method to create photo-like two dimensional images of the inner
surfaces of the casing, while the tool is being axially moved
(`logged`) through the wellbore, such that a consolidated two
dimensional image of the well casing can be produced. It also fails
to teach or suggest a method and means that uses a fixed
conical/panoramic beam to illuminate the well casing, whereas the
directional collimation is located at the rotating detector.
[0016] U.S. Pat. No. 5,326,970 to Bayless discloses a tool that
aims to measure backscattered x-rays azimuthally in a single
direction to measure formation density, with the x-ray source being
based on a linear accelerator. However, the reference fails to
disclose a means or method to create photo-like two dimensional
images of the inner surfaces of the casing, while the tool is being
axially moved through the wellbore, such that a consolidated two
dimensional image of the well casing can be produced.
[0017] U.S. Pat. No. 5,081,611 to Hornby discloses a method of back
projection to determine acoustic physical parameters of the earth
formation longitudinally along the borehole using a single
ultrasonic transducer and a number of receivers, which are
distributed along the primary axis of the tool.
[0018] U.S. Pat. No. 6,725,161 to Hillis discloses a method of
placing a transmitter in a borehole, and a receiver on the surface
of the earth, or a receiver in a borehole and a transmitter on the
surface of the earth, with the aim to determine structural
information regarding the geological materials between the
transmitter and receiver.
[0019] U.S. Pat. No. 6,876,721 to Siddiqui discloses a method to
correlate information taken from a core-sample with information
from a borehole density log. The core-sample information is derived
from a CT scan of the core-sample, whereby the x-ray source and
detectors are located on the outside of the sample, and thereby
configured as an outside-looking-in arrangement. Various kinds of
information from the CT scan such as its bulk density is compared
to and correlated with the log information.
[0020] U.S. Pat. No. 4,464,569 to Flaum discloses a method to
determine the elemental composition of earth formations surrounding
a well borehole by processing the detected neutron capture gamma
radiation emanating from the earth formation after neutron
irradiation of the earth formation by a neutron spectroscopy
logging tool.
[0021] U.S. Pat. No. 4,433,240 to Seeman discloses a borehole
logging tool that detects natural radiation from the rock of the
formation and logs said information so that it may be represented
in an intensity versus depth plot format.
[0022] U.S. Pat. No. 3,976,879 to Turcotte discloses a borehole
logging tool that detects and records the backscattered radiation
from the formation surrounding the borehole by means of a pulsed
electromagnetic energy or photon source, so that characteristic
information may be represented in an intensity versus depth plot
format.
[0023] U.S. Pat. No. 6,078,867 to Plumb discloses a method for
generating a three-dimensional graphical representation of a
borehole, comprising the steps of: receiving caliper data relating
to the borehole, generating a three-dimensional wire mesh model of
the borehole from the caliper data, and color mapping the
three-dimensional wire mesh model from the caliper data based on
either borehole form, rigosity and/or lithology.
SUMMARY
[0024] An x-ray-based cased wellbore tubing and casing imaging tool
is provided, the tool including at least a shield to define the
output form of the produced x-rays; a two-dimensional per-pixel
collimated imaging detector array; a parallel hole collimator
format in one direction that is formed as a pinhole in another
direction; Sonde-dependent electronics; and a plurality of tool
logic electronics and PSUs.
[0025] A method of using an x-ray-based cased wellbore tubing and
casing imaging tool is also provided, the method including at
least: producing x-rays in a shaped output; measuring the intensity
of backscatter x-rays returning from materials surrounding a
wellbore; determining an inner and an outer diameter of tubing or
casing from the backscatter x-rays; and converting image data from
the detectors into consolidated images of the tubing or casing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 illustrates an x-ray-based tubing, casing,
perforation, or side-pocket mandrel imaging tool being deployed
into a borehole via wireline conveyance. Regions of interest within
the materials surrounding the borehole are also indicated.
[0027] FIG. 2 illustrates an example embodiment of an x-ray-based
tubing imaging and measurement tool, arranged so as to enable
imaging of the inner-most casing or tubing, and illustrating the
ability to change modes to perform a geometric measurement of the
thickness of the tubing.
[0028] FIG. 3 illustrates an example embodiment of an x-ray-based
tubing imaging and measurement tool, arranged so as to perform a
geometric measurement of the thickness of the tubing, and in
particular to determine the inner diameter and the outer diameter
of the tubing.
[0029] FIG. 4 illustrates how the intensity of detected x-rays can
be translated directly into a geometric position within the tubing
or casing, indicating the position of the inner diameter and the
outer diameter.
[0030] FIG. 5 illustrates how the intensity of detected x-rays can
be translated directly into a geometric position within the tubing
or casing, indicating the position of the inner diameter of scale,
simultaneously with the inner diameter of the tubing and the outer
diameter.
BRIEF DESCRIPTION OF SEVERAL EXAMPLE EMBODIMENTS
[0031] Various methods and means for performing casing and tubing
integrity evaluation are disclosed which, while simultaneously
imaging equipment/features located immediately surrounding the
borehole, using x-ray backscatter imaging in a cased wellbore
environment, do not require direct physical contact with the well
casings (i.e., non-padded). The methods and means herein further
consist employing a combination of collimators, located
cylindrically around an X-ray source, located within a non-padded
concentrically-located borehole logging tool, together with a
plurality of fixed three-dimensional hybrid collimated imaging
detector array(s) to also be used as the primary imaging
detector(s). The ability to control the solid angle of the
collimated source permits the operator to either log the tool
through the well casing while the detectors measure the inner
diameter and outer diameter of tubing or casing, to produce a fully
azimuthal two dimensional backscatter x-ray image, and to hold the
tool stationary as the collimated detectors image azimuthally to
capture a cylindrical image that can be improved upon `statically`
(as the detector continues to recapture casing images that can be
added to the existing image set).
[0032] In one example embodiment, and, with reference now to the
illustration provided in FIG. 1, an x-ray-based tubing imaging tool
[101] is deployed by wireline conveyance [104] into a tubing [102]
within a cased [103] borehole, wherein the well casing or tubing
[102] is imaged. The tool is enclosed by a pressure housing [201]
which ensures that well fluids are maintained outside of the
housing.
[0033] FIG. 2 illustrates an example embodiment in which a pressure
housing [201] is conveyed through a well casing or tubing [202].
The pressure housing contains an electronic x-ray source [203] that
is configured to produce x-rays panoramically in a conical output
[204], the shape and distribution of said x-ray output is
determined by the geometry of an actuatable source collimator [205,
208] which is formed by creating a non-blocking region of the
radiation shielding. The conical x-ray beam [204] illuminates a
cylindrical section of the casing/tubing [204]. The radiation
scattering from the casing is imaged by an azimuthally arranged
plurality of two-dimensional detector arrays [206], which are
collocated with three-dimensional parallel hole collimators [207a,
207b]. The detector collimators reduce the field of view of each
pixel of the detector array such that each pixel images a distinct
and unique section of the illuminated casing/tubing. The
collimators are formed such that, in the transverse direction, they
form the geometry of a typical pinhole detector [207a], however, in
the axial-radial direction they form the geometry of a plurality of
parallel hole collimators [207b]. In a further embodiment, the
source collimator may be actuated [208], by command of the operator
without removing the tool from the borehole, such that one axial
component of the collimator [205] moves to reduce the solid-angle
of the source-output, resulting in a very narrow conical beam
[209], or plurality of individual beams that create a conical form.
The tool is then arranged so that the narrow conical beam
intersects the tubing or casing and can be used to measure the
thickness of the tubing or casing more precisely. As the axial
offset for each pixel is known, along with the angle and
field-of-view of the collimator, as well as the angle and
divergence of the beam, it is simple to remap each pixel to a
radially positioned voxel along the beam-path, the form of which
may be plotted as intensity [210] versus axial or radial offset
[211] to produce a backscatter profile [212] of the tubing or
casing material.
[0034] In another example embodiment, the concentricity of the tool
[101] compared to the tubing or casing [302] does not affect the
geometric relation of the measurement with respect to the inner
diameter and the outer diameter of the tubing or casing [302]. If
the tool housing [301] standoff is reduced in the direction of the
tubing or casing [302] then the conical x-ray beam [303] interacts
with the tubing or casing [302] in a different position, such that
the higher intensity region [304] of scattering photons being
detected will appear to move toward the source anode position
axially. On the opposite side of the tool (180 degrees away), the
tool housing [301] standoff will be increased away from the tubing
or casing [302] then the conical x-ray beam [303] will interact
with the tubing or casing [302] in a different position, such that
the higher intensity region [305] of scattering photons being
detected will appear to move away from the source anode position
axially. The result would be that the movement of the higher
intensity region [304] when plotted as intensity [306] versus axial
or radial offset [307] to form a profile [308] of the tubing or
casing will shift but without changing the overall form of the
tubing or casing profile, as the source beam angle will not have
changed. Conversely, on the opposite side of the tool (180 degrees
away) the result would be that the movement of the higher intensity
region [305] when plotted as intensity [306] versus axial or radial
offset [307] to form a profile [309] of the tubing or casing, will
shift but without changing the overall form of the tubing or casing
profile, as the source beam angle will not have changed. The change
in position of the two profiles [308, 309] can be used to determine
both the position of the tool within the tubing, and the diameter
of the inner diameter of the tubing as a function of azimuth around
the tool.
[0035] In a further embodiment the axial offset for each pixel is
known, along with the angle and field-of-view of the collimator and
the angle and divergence of the beam, it is simple to remap each
pixel to a radially positioned voxel along the beam-path, the form
of which may be plotted as intensity [402] versus axial or radial
offset [402] to produce a backscatter profile of the tubing or
casing material, the leading edge of the plot [403] is also
co-located with the highest rate of change in intensity [401]. When
the return falls to near zero backscatter intensity, the outer
diameter [404] may also be determined.
[0036] In a further embodiment, the tool is then arranged such that
the narrow conical beam intersects the tubing or casing and can be
used to measure the thickness of the tubing or casing precisely, in
addition to the thickness of scale deposits on the inner-diameter
of the tubing/casing. As the axial offset for each pixel is known,
along with the angle and field-of-view of the collimator, and the
angle and divergence of the beam, it is simple to remap each pixel
to a radially positioned voxel along the beam-path. A plot of
intensity [501] versus radial distance, derived from the geometric
remapping of intensity as a function of detector pixel position
relative to the source output [502] may be used to determine the
position of the inner diameter of scale deposits [503] upon the
inner diameter of the tubing or casing, and the inner diameter of
the tubing or casing [504], in addition to the outer diameter of
the tubing or casing.
[0037] In a further embodiment, the radial inspection detector
assemblies are used to create images of sand-screens, as well as to
aid inspection.
[0038] In a further embodiment, the radial inspection detector
assemblies are used to create images of side pocket mandrels, and
to aid inspection.
[0039] In a still further embodiment, the radial inspection
detector assemblies are used to create images of perforations, and
to aid inspection and to map and size perforations.
[0040] In a further embodiment still, the radial inspection
detector assemblies are used to create images of frac-sleeves.
[0041] In another embodiment, as the tool is logged axially, each
axial `column` of pixels of the detector arrays are sampled so that
each column will image a similar section of the casing/tubing that
had been imaged by a neighboring section during the prior sample.
Upon encoding the images with the known azimuthal capture position
of the image section, the separate image pixel columns associated
with each imaged `slit` section of the casing/tubing are summated
or averaged to produce a higher quality image within a single
pass.
[0042] In a further embodiment, the operator interrupts conveyance
of the tool and uses the azimuthally imaging detector assembly to
continually sample the same images tubing/casing illuminated
cylinder section, so that the resulting data set can build/summate
statistically to improve image quality.
[0043] In another embodiment, the backscatter images contain
spectral information, so that a photo-electric or
characteristic-energy measurement can be taken, and the imaged
material analyzed for scale-build up or casing corrosion.
[0044] In a further embodiment, machine learning is employed to
automatically analyze the spectral (photo electric or
characteristic energy) content of the images and identify key
features, such as corrosion, holes, cracks, scratches, and/or
scale-buildup.
[0045] In a further embodiment, the per-pixel collimated imaging
detector array is a single `strip` array (i.e., one pixel wide
azimuthally, and multiple pixels long axially), the imaging result
would be a `cylindrical` ribbon image. The tool is then moved
axially (either by wireline-winch or with a stroker) and a new
image set taken, so that a section of casing is imaged by stacking
cylindrical ribbon images/logs.
[0046] In a further embodiment, machine learning is employed to
automatically reformat (or re-tesselate) the resulting images as a
function of depth and varying logging speeds or logging steps such
that the finalized casing and/or cement image is accurately
correlated for azimuthal direction and axial depth, by comparing
with CCL, wireline run-in measurements, and/or other pressure/depth
data.
[0047] The foregoing specification is provided only for
illustrative purposes, and is not intended to describe all possible
aspects of the present invention. While the invention has herein
been shown and described in detail with respect to several
exemplary embodiments, those of ordinary skill in the art will
appreciate that minor changes to the description, and various other
modifications, omissions and additions may also be made without
departing from the spirit or scope thereof.
* * * * *