BACKGROUND
[0001] The present disclosure relates generally to wellbore ranging and, more
particularly, to visualizing drilling trajectories of adjacent wellbores using periodic
measurements and determining locations at which to take additional periodic measurements.
[0002] Hydrocarbons, such as oil and gas, are commonly obtained from
subterranean formations that may be located onshore or offshore. In some instances, operations
for removing the hydrocarbons from the subterranean formations may include drilling a second
wellbore in close proximity to a first wellbore. The wellbores may intersect or not intersect,
depending on the application. For example, a blowout (i.e., an uncontrolled release of
hydrocarbons from the wellbore) may occur in the first wellbore, which may require the drilling
of a second relief wellbore that purposefully intersects with the first wellbore at some depth. As
another example, Steam Assisted Gravity Drainage (SAGD) techniques may call for two
wellbores to be drilled somewhat parallel to one another that do not intersect. It may therefore
be desirable to obtain information about the locations of the two wellbores with respect to one
another during drilling. To do so, periodic measurements may be taken while drilling.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] For a more complete understanding of the present disclosure and its
features and advantages, reference is now made to the following description, taken in
conjunction with the accompanying drawings, in which:
[0004] FIGURE 1 illustrates an example drilling system, in accordance with
embodiments of the present disclosure;
[0005] FIGURE 2 illustrates a block diagram of an exemplary computing system
for use in the drilling system of FIGURE 1, in accordance with embodiments of the present
disclosure;
[0006] FIGURE 3 illustrates an example visualization of the respective locations
of the wellbores of FIGURE 1 based on periodic measurements, in accordance with
embodiments of the present disclosure; and
[0007] FIGURE 4 illustrates an example method for determining a next location
at which to take a ranging measurement, in accordance with embodiments of the present
disclosure.
[0008] While embodiments of this disclosure have been depicted and described
and are defined by reference to example embodiments of the disclosure, such references do not
imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter
disclosed is capable of considerable modification, alteration, and equivalents in form and
function, as will occur to those skilled in the pertinent art and having the benefit of this
disclosure. The depicted and described embodiments of this disclosure are examples only, and
not exhaustive of the scope of the disclosure.
DETAILED DESCRIPTION
[0001] The present disclosure describes systems and methods for visualizing the
respective locations of adjacent wellbores in three dimensions based on measurements taken at
different depths. This may be done through the use of survey and/or ranging measurements.
Survey measurements may be taken uphole (e.g., at the surface of a drilling system) and may
provide data that may assist in determining the position of a wellbore in three dimensions with
respect to the formation. Survey measurements may come from tools such as accelerometers or
gyroscopes located at various locations near a wellbore. Ranging measurements, on the other
hand, may be taken from within one of the two wells and may provide data that may assist in
determining the positions of the two wells with respect to one another. Ranging measurement
may come from magnetic or electromagnetic measurement tools located at various locations
within a wellbore.
[0002] The visualization of the respective well locations may include both past
trajectory (e.g., based on past ranging measurements) as well as projected future trajectory
(based on the current drilling path). In particular embodiments, the location of the second
wellbore may be determined using ranging and/or survey measurements. As such, measurement
error ranges (from either the ranging or survey measurements) may be determined and indicated
in the visualization. In some embodiments, uncertainty values may be determined and
represented in the visualization (e.g., through cones or ellipses) for each projected wellbore
trajectory based on uncertainty models, such as the Wolfe Dewardt ellipse uncertainty model.
Using the projected trajectory paths incorporating the determined uncertainty values, areas of
potential collision between the wells may be determined and indicated in the visualization. In
addition, using the projected trajectories, depths at which to take additional survey measurements
may be determined and displayed in the visualization. Each of the determined and/or displayed
data (e.g., the trajectories or error ranges) may be updated as additional survey and/or ranging
measurements are taken.
[0003] By providing three-dimensional visualization and determinations of
locations at which to take additional ranging measurements, the present disclosure is well
adapted to allow an operator of drilling equipment to more easily understand the impact of the
current wellbore steering relative to a second wellbore and to provide a novel approach to
determining when another ranging measurement may be necessary. The present disclosure is
also well adapted to allow for the merging of the uncertainty of ranging measurements with the
uncertainty of survey measurements into a single visualization. As such, the present disclosure
may provide a more accurate and cohesive visualization of the respective locations and
trajectories of multiple adjacent wellbores.
[0004] To facilitate a better understanding of the present disclosure, the following
examples of certain embodiments are given. In no way should the following examples be read to
limit, or define, the scope of the disclosure. Embodiments of the present disclosure and its
advantages are best understood by referring to FIGURES 1 through 4, where like numbers are
used to indicate like and corresponding parts.
[0005] FIGURE 1 illustrates an example drilling system 100, in accordance with
embodiments of the present disclosure. The drilling system 100 includes a rig 101 located at a
surface 111 and positioned above a wellbore 103 within a subterranean formation 102. In certain
embodiments, a drilling assembly 104 may be coupled to the rig 101 using a drill string 105. In
other embodiments, the drilling assembly 104 may be coupled to the rig 101 using a wireline or a
slickline, for example. The drilling assembly 104 may include a bottom hole assembly (BHA)
106. The BHA 106 may include a drill bit 109, a steering assembly 108, and a LWD/MWD
apparatus 107. A control unit 110 located at the surface 11 may include a processor and
memory device (e.g., computing device 200 of FIGURE 2), and may communicate with
elements of the BHA 106, in the LWD/MWD apparatus 107, and the steering assembly 108.
The control unit 110 may receive data from and send control signals to the BHA 106.
Additionally, at least one processor and memory device may be located downhole within the
BHA 106 for the same purposes. The LWD/MWD apparatus 107 may log the formation 102
both while the wellbore 103 is being drilled, and after the wellbore is drilled to provide
information regarding ongoing subterranean operations. For example, LWD/MWD apparatus
may log a trajectory of the wellbore 103, take periodic ranging measurements to determine a
relative location of wellbore 113, or determine one or more characteristics of formation 102 (e.g.,
formation resistivity, hardness, and/or type) during drilling operations. The steering assembly
108 may include a mud motor that provides power to the drill bit 109, and that is rotated along
with the drill bit 109 during drilling operations. The mud motor may be a positive displacement
drilling motor that uses the hydraulic power of the drilling fluid to drive the drill bit 109. In
accordance with an embodiment of the present disclosure, the BHA 106 may include an
optionally non-rotatable portion. The optionally non-rotatable portion of the BHA 106 may
include any of the components of the BHA 106 excluding the mud motor and the drill bit 109.
For instance, the optionally non-rotatable portion may include a drill collar, the LWD/MWD
apparatus 107, bit sub, stabilizers, jarring devices and crossovers. In certain embodiments, the
steering assembly 108 may angle the drill bit 109 to drill at an angle from the wellbore 103.
Maintaining the axial position of the drill bit 09 relative to the wellbore 103 may require
knowledge of the rotational position of the drill bit 109 relative to the wellbore 103.
[0006] Wellbore 103 may be relatively adjacent to wellbore 113, as shown in
FIGURE 1. Wellbore 113 may be an existing wellbore for a hydrocarbon producing well, or
may be a wellbore being drilled simultaneously with wellbore 103 with a drilling system similar
to rig 101 and its components 103-109. In particular embodiments, wellbore 103 may be drilled
in such a way that it intersects with wellbore 13 at a particular point. For example, wellbore
113 may be an existing well experiencing a blowout or other issue, and wellbore 103 may be
drilled to be a relief well that intersects with wellbore 13. In other embodiments, wellbore 103
may be drilled such that it does not ever intersect with wellbore 13. For example, wellbores
103 and 13 may be twinned or parallel wells for use in SAGD drilling applications.
[0007] Modifications, additions, or omissions may be made to FIGURE 1 without
departing from the scope of the present disclosure. For example, FIGURE 1 illustrates
components of drilling system 100 in a particular configuration. However, any suitable
configuration of drilling components for drilling a hydrocarbon well may be used. Furthermore,
although not illustrated in FIGURE 1, it will be understood that wellbore 3 may include one or
more drilling components (e.g., for embodiments wherein wellbore 113 is drilled simultaneously
with wellbore 103) or components for extracting hydrocarbons (e.g., for embodiments wherein
wellbore 1 3 is a hydrocarbon producing well).
[0008] FIGURE 2 illustrates a block diagram of an exemplary computing system
200 for use in drilling system 100 of FIGURE 1, in accordance with embodiments of the present
disclosure. Computing system 200 or components thereof can be located at the surface (e.g., in
control unit 10), downhole (e.g., in BHA 106 and/or in LWD/MWD apparatus 107), or some
combination of both locations (e.g., certain components may be disposed at the surface while
certain other components may be disposed downhole, with the surface components being
communicatively coupled to the downhole components).
[0009] Computing system 200 may be configured to visualize the respective
locations of a first wellbore and an adjacent second wellbore based on periodic measurements
(e.g., ranging and/or survey measurements), in accordance with the teachings of the present
disclosure. For example, computing system 200 may be configured to generate a visualization
similar to visualization 300 of FIGURE 3 in some embodiments. In addition, computing system
200 may be configured to determine a location at which to take a next periodic ranging
measurement during drilling. For example, computing system 200 may be used to perform the
steps of the method described below with respect to FIGURE 4.
[0010] In particular embodiments, computing system 200 may include wellbore
ranging module 202. Wellbore ranging module 202 may include any suitable components. For
example, in some embodiments, wellbore ranging module 202 may include processor 204.
Processor 204 may include, for example a microprocessor, microcontroller, digital signal
processor (DSP), application specific integrated circuit (ASIC), or any other digital or analog
circuitry configured to interpret and/or execute program instructions and/or process data. In
some embodiments, processor 204 may be communicatively coupled to memory 206. Processor
204 may be configured to interpret and/or execute program instructions or other data retrieved
and stored in memory 206. Program instructions or other data may constitute portions of
software 208 for carrying out one or more methods described herein. Memory 206 may include
any system, device, or apparatus configured to hold and/or house one or more memory modules;
for example, memory 206 may include read-only memory, random access memory, solid state
memory, or disk-based memory. Each memory module may include any system, device or
apparatus configured to retain program instructions and/or data for a period of time (e.g.,
computer-readable non-transitory media). For example, instructions from software 208 may be
retrieved and stored in memory 206 for execution by processor 204.
[001 1] In particular embodiments, wellbore ranging module 202 may be
communicatively coupled to one or more displays 210 such that information processed by
wellbore ranging module 202 may be conveyed to operators of drilling and logging equipment.
For example, wellbore ranging module 202 may convey ranging, survey, or other measurements
from LWD/MWD apparatus 107 to display 210. As another example, wellbore ranging module
202 may generate one or more visualizations of the wellbores and their respective trajectories,
similar to visualization 300 of FIGURE 3.
[0012] Modifications, additions, or omissions may be made to FIGURE 2 without
departing from the scope of the present disclosure. For example, FIGURE 2 shows a particular
configuration of components of computing system 200. However, any suitable configurations of
components may be used. For example, components of computing system 200 may be
implemented either as physical or logical components. Furthermore, in some embodiments,
functionality associated with components of computing system 200 may be implemented in
special purpose circuits or components. In other embodiments, functionality associated with
components of computing system 200 may be implemented in configurable general purpose
circuit or components. For example, components of computing system 200 may be implemented
by configured computer program instructions.
[0013] FIGURE 3 illustrates an example visualization 300 of the respective
locations of wellbores 103 and 113 of FIGURE 1 based on periodic measurements, in
accordance with embodiments of the present disclosure. In particular, FIGURE 3 illustrates a
perspective view of wellbore 103 and wellbore 13 looking down from the surface and from an
angle off to the left of the two wellbores. In certain embodiments, an operator of a drilling
system may rotate, zoom, or otherwise manipulate the visualization to any desired perspective
during drilling operations. In certain embodiments, an orthogonal axis indicator 301 may be
provided as shown in FIGURE 3 to aid an operator of the drilling system in understanding the
relative orientations and positions of the two wells with respect to some reference (e.g., the
surface). Visualization 300 includes the past trajectories 3 and 321 of wellbores 103 and 113,
respectively, as well as the future trajectories 312 and 322 of wellbores 103 and 113,
respectively. Past trajectories 3 11 and 321 may represent the path of the respective wellbores in
formation 102 at depths above a current depth of one or both wellbores (such as current depth
310 of wellbore 103 or current depth 320 of wellbore 13), while future trajectories 312 and 322
may represent the path of the respective wellbores in formation 102 at depths below a current
depth of one or both wellbores. For example, in embodiments where wellbore 103 is to be a
relief well for existing wellbore 113, future trajectory 312 of wellbore 103 may represent the
projected path of wellbore 103 at current steering conditions for wellbore 103, while future
trajectory 322 of wellbore 113 may represent a predicted path of the existing wellbore 13 based
on survey and/or ranging measurements. As another example, in embodiments where wellbore
103 and wellbore 113 are drilled simultaneously, future trajectory 312 of wellbore 103 may
represent the projected path of wellbore 103 based on measurements such as survey or ranging
measurements, while future trajectory 322 of wellbore 113 may represent the projected path of
wellbore 113 based on current steering conditions and/or measurements such as survey or
ranging measurements.
[0014] Visualization 300 includes three ranging measurements 330 taken from
wellbore 310 at different depths, which may indicate an estimated distance between the first
wellbore 310 and the second wellbore 320. In certain embodiments, visualization 300 may
include indications of the depths at which the ranging measurements have been taken (not shown
in FIGURE 3). Ranging measurements 330 may each be associated with a ranging error, which
may indicate a confidence level of the ranging measurements with respect to the distance and/or
direction determined by the ranging measurement 330. In certain embodiments, the ranging
error may be indicated in visualization 300 (shown in FIGURE 3 as the shaded section
surrounding past trajectory 321 of wellbore 320, referred to herein as the ranging error window
335). Based on the ranging error, a minimum and a maximum associated with the distance of the
second wellbore from the first wellbore may be determined, in particular embodiments. A range
associated with the direction of the second wellbore from the first wellbore may also be
determined, in certain embodiments. As shown in FIGURE 3, the first arc in the ranging error
window 335 indicates the determined minimum distance to the second wellbore, while the top
arc of the ranging error window 335 indicates the determined maximum distance to the second
wellbore. The left and right sides of the ranging error window 335 represent the determined
range of directional error to the second wellbore. In particular embodiments, the ranging error
window 335 may represent a plane in the formation in which the second wellbore could reside.
The size of the ranging error window 335 may be determined by the accuracy of the ranging
measurement, and may change with each ranging measurement taken during drilling (e.g., due to
varying formation properties at the different depths).
[0015] Wellbore 103 and/or wellbore 13 may be shaded, colored, or otherwise
noted in visualization 300 to indicate one or more properties of the formation, in particular
embodiments. Such indications may aid an operator of the drilling system in determining
potential causes for the ranging error determined. For example, first wellbore 310 may be
shaded at the various depths indicated in visualization 300 to indicate a resistivity of the
formation, a type of the formation, or a strength of the formation. As another example, first
wellbore 310 may be colored in SAGD drilling systems to indicate particular segments at which
the first wellbore 310 is in good separation distance from second wellbore 320 and/or segments
at which the first wellbore 310 is too close to second wellbore 320, which may aid the drilling
operator in properly steering the wellbore for SAGD recovery operations and avoiding unwanted
intersections.
[0016] In embodiments where ranging error window 335 is indicated in
visualization 300, the error window values for intermediate depths may be determined using
interpolation techniques. It will be understood that any suitable interpolation technique may be
used to determine and visualize the ranging error window 335 in visualization 300. For instance,
a minimum curvature method may be used along with a linear scaling method to adjust for the
error window size relative to the size of wellbore 13. Three-dimensional perspective may then
be added to the visualization to make objects farther away appear smaller and those closer appear
bigger.
[0017] Visualization 300 may also include a representation of error for future
trajectories 312 and 322, in particular embodiments. For instance, error models based on the
cumulative effect of survey measurements (e.g., the Wolfe-Dewardt ellipse of uncertainty model)
may be used to determine a range of error in the future trajectories 312 and 322. This range of
error may be illustrated in visualization with a conical or elliptical shading, as shown in FIGURE
3 as the conical shading surrounding future trajectories 312 and 322 (referred to herein as the
survey error window 340). In certain embodiments, the survey error window 340 may begin
with an error of zero at current depths 310 and 320 and expand as the depth increases as shown
in FIGURE 3, or may begin at the value of the ranging error determined at current depths 310
and 320 and expand from that value as the depth increases (i.e., the survey error window 340
would begin at the end of the ranging error window 335). In certain embodiments, the
determined ranging error and survey error may be merged at and near the point of transition (i.e.,
at depth 320) between the two models, such that the maximum error determined for each in any
direction is used to represent the area of uncertainty (i.e., the survey error window 340) from the
transition point forward. For example, the shape of the survey error window 340 may transition
from a ring segment shape (as shown in visualization 300 as ranging error window 335) to an
elliptical shape (as shown in visualization 300 as survey error window 340) over a depth interval
as the ellipse error grows in size relative to the ranging error as depth increases beyond the
transition point between the ranging error and survey error. In particular embodiments,
visualization 300 may further include a representation of where the survey error windows 340 for
wellbore 103 and 1 3 overlap (referred to herein as collision zone 345), which may indicate a
potential area of collision between the two wellbores.
[0018] Visualization 300 may be updated as drilling progresses, in particular
embodiments. For instance, the past trajectories 3 11 and 321 and future trajectories 312 and 322
may each be updated as drilling progresses further into the formation (i.e., as the current depths
310 and 320 change). Future trajectories 312 and 322 may also be updated as steering of
wellbores 103 or 113 changes. In addition, the ranging error window 335 and survey error
windows 340 may change as drilling progresses and/or as additional measurements are taken.
This may include resetting the starting point (either zero or at the latest value of the ranging error
window 335) of survey error windows 340 each time the current depths 310 and 320 change or
each time an additional measurement is taken. Furthermore, as the survey error windows 340
change, the indicated collision zone 345 may change accordingly.
[0019] As described further below with respect to FIGURE 4, a future depth at
which to take the next ranging measurement 330 may be determined based on one or more
factors (e.g., based on the current locations of the wellbores and the projected trajectories of the
wellbores), and may be indicated in visualization as a next measurement depth 350.
[0020] Alerts may be generated and indicated in visualization 300, in particular
embodiments. For example, an alert may be generated to an operator of the drilling system
based on the determined next measurement depth 350, such as when the current drilling depth
310 is nearing the next measurement depth 350. In some embodiments, if an operator goes past
the recommended next measurement depth 350, the drilling system may discontinue drilling until
further measurements are taken. As another example, an alert may be generated based on future
trajectories 312 and 322, such as when the trajectories suggest that the wellbores 103 and 1 3
may stray outside of a target separation distance range (which may also be indicated in
visualization 300, similar to how collision zone 345 is indicated in FIGURE 3).
[0021] Modifications, additions, or omissions may be made to FIGURE 3 without
departing from the scope of the present disclosure. For example, other indicators may be
included in visualization beyond those depicted, such as depth indicators or formation property
indicators. In addition, the shapes, shading, or colors of the items in visualization 300 may
depend on the drilling application or desired outcomes. For example, collision zone 350 may be
colored red when intersection between wellbores 103 and 1 3 is not desired (e.g., in SAGD
applications), and colored green when intersection between wellbores 103 and 13 is desired
(e.g., in relief well applications).
[0022] FIGURE 4 illustrates an example method 400 for determining a next
location at which to take a ranging measurement, in accordance with embodiments of the present
disclosure. The method begins at step 410, where survey measurement information and ranging
measurement information are received. The information may be received at a computing system
such as computing system 200 of FIGURE 2, and may be received from any suitable survey and
ranging measurement systems, respectively. For instance, a survey measurement may be taken
at the surface of a wellbore using accelerometers or gyroscopes to obtain information about
formation 102 of FIGURE 1, and may then conveyed to control unit 110 for processing.
Ranging measurements may be taken from within a first wellbore in the formation, for example,
using electromagnetic signals.
[0023] Using the received survey measurement information, the location of a first
wellbore within a formation may be determined at step 420. Similarly, using the received
ranging measurement information, the location of a second wellbore within a formation at step
430. The determined location of the second wellbore may be with respect to the first wellbore,
in some embodiments. In certain embodiments, the received survey measurement information
may also be used to determine the location of the second wellbore in the formation. The
locations of the first wellbore and second wellbore may include past trajectories of the respective
wellbores (e.g., what is visualized in FIGURE 3 as past trajectories 3 11 and 321), or a path that
the respective wellbore has taken through the formation up to a current depth. In certain
embodiments, the locations of the first wellbore and second wellbore may include future
trajectories of the respective wellbores (e.g., what is visualized in FIGURE 3 as future
trajectories 312 and 322). The future trajectories may be projected for incomplete wellbores
(e.g., a relief well being drilled to intersect with a blowout wellbore) and may be based on a
current depth, past trajectory, and/or current steering angle of a drilling system in some
embodiments. The future trajectories may also be estimated for an existing wellbore (e.g., the
blowout well in a relief well drilling application) and may be based on survey measurements in
some embodiments.
[0024] At step 440, errors associated with the determined locations of the first
wellbore and the second wellbore are determined. The errors may be associated with the past
trajectory of the respective wellbore, the future trajectory of the respective wellbore, or both. For
example, the error for the past trajectory of the second may include a ranging error calculation.
The ranging error calculation may be based on the ranging measurement equipment used or
properties of the formation, for example. An example ranging error may be seen with reference
to ranging error window 335 in FIGURE 3. As another example, an error for a past or future
trajectory of a wellbore may include a survey error calculation. The survey error calculation may
be based on the survey measurement equipment used or properties of the formation, for example.
An example survey error calculation may be seen with reference to error window 340 for
wellbore 113 in FIGURE 3. In particular embodiments, the errors associated with the future
trajectories of the wellbore may be based on a cumulative model, such as the Wolfe-Dewardt
ellipse of uncertainty model.
[0025] At step 450, a next location at which to take another ranging measurement
is determined. The determined next location may be based on the location of the first wellbore,
the location of the second wellbore, the determined errors associated with the respective
locations of the first wellbore and the second wellbore, or any combination thereof. In certain
embodiments, the determined location at which to take another ranging measurement may be
based on a determined potential intersection location between the first and second wellbores.
The potential intersection location may be determined based on the location of the first wellbore,
the location of the second wellbore, the determined errors associated with the respective
locations of the first wellbore and the second wellbore, or any combination thereof. For
example, the potential intersection location may be determined by calculating future trajectories
of the two respective wellbores, and then further taking into account determined errors with
respect to those future locations. Referring to FIGURE 3, the future trajectories 312 and 322
may have error windows 340 associated therewith, and the potential intersection location may be
determined by when the error windows overlap (shown in FIGURE 3 as collision zone 345).
The determined location at which to take another ranging measurement may be near the
determined potential intersection location, and may be well before the determined potential
intersection location to avoid a potential collision between the wellbores.
[0026] At step 460, the locations of the first and second wellbore are visualized.
The visualization may be similar to visualization 300 of FIGURE 3 with a particular perspective
view, and may include any suitable visualization of an aspect of the first wellbore or second
wellbore. For example, the visualization may include the past and future trajectories of the
wellbores. As another examples, the visualization may include an axis indicator for reference to
the perspective view of the visualization. In certain embodiments, the perspective view of the
visualization may be modified. For example, the visualization may be zoomed or rotated by an
operator of a drilling system. Furthermore, the visualization may be updated periodically. For
example, the visualization may be updated as additional data is collected, such as additional
ranging or survey measurement information as described below.
[0027] In particular embodiments, a second ranging measurement may be taken
near the location determined at step 450 (not shown in FIGURE 4). In some embodiments, this
may also include taking additional survey measurements. With the new ranging and/or survey
measurement information obtained from the new ranging and survey measurements, the
respective locations of the first and second wellbore may be updated and the steps of method 400
may be repeated. For example, a new location at which to take another ranging measurement
may be determined, and the relevant information in the visualization may be updated
accordingly.
[0028] In particular embodiments, one or more alerts may be generated before or
after any of steps 410-460. The alerts may be based on information gathered or determined by
the drilling system. For example, the alerts may indicate the next location at which to take
another ranging measurement determined at step 450, which may be based on the locations or
associated errors for the respective wellbores. As the drilling system nears the determined
location (e.g., the system is within 100 meters of the determined location), the alert may be
generated to make an operator aware of the potential need to take another ranging location. As
another example, the alerts may indicate close proximity of the drilling system to a determined
potential intersection location. For example, an alert may be generated as a drilling system
comes within 200 meters of a potential intersection location in order to alert an operator of a
potential collision with another wellbore.
[0029] Modifications, additions, or omissions may be made to method 400
without departing from the scope of the present disclosure. For example, the order of the steps
may be performed in a different manner than that described and some steps may be performed at
the same time. Additionally, each individual step may include additional steps without departing
from the scope of the present disclosure.
[0030] To provide illustrations of one or more embodiments of the present
disclosure, the following examples are provided. In one embodiment, a wellbore ranging system
comprises a processor, a memory, and a wellbore ranging module. The wellbore ranging module
is operable to receive survey information in response to a survey measurement signal and
determine, based on the survey information, a location of a first wellbore in a formation. The
wellbore ranging module is also operable to receive first ranging information in response to a
first ranging measurement signal sent from the first wellbore at a first depth in the first wellbore,
and determine, based on the first ranging information, a location of a second wellbore in the
formation and a second wellbore location error associated with the determined location of the
second wellbore in the formation. The wellbore ranging module is further operable to determine,
using the location of the first wellbore, the location of the second wellbore, and the second
wellbore location error, a second depth in the first wellbore at which to send a second ranging
measurement signal.
[0031] In one or more aspects of the disclosed system, the location of a second
wellbore is further based on the received survey information, and the second wellbore location
error is further based on the received survey information. In one or more aspects of the disclosed
system, the determined location of the first wellbore comprises a past trajectory of the first
wellbore in the formation, and the determined location of the second wellbore comprises a past
trajectory of the second wellbore in the formation. In one or more aspects of the disclosed
system, the determined location of the second wellbore further comprises a future trajectory of
the second wellbore in the formation, and the wellbore ranging module is further operable to
determine a future trajectory of the first wellbore based on the location of the first wellbore in the
formation and a current steering angle of the first wellbore. In one or more aspects of the
disclosed system, the wellbore ranging module is further operable to determine a first wellbore
location error associated with the future trajectory of the first wellbore, and the second wellbore
location error comprises a first portion and a second portion, the first portion being associated
with the past trajectory of the second wellbore and the second portion being associated with the
future trajectory of the second wellbore. In one or more aspects of the disclosed system, the
wellbore ranging module is further operable to determine, using the first wellbore location error
and the second wellbore location error, a location in the formation at which an intersection of the
first wellbore and the second wellbore may occur. In one or more aspects of the disclosed
system, the wellbore ranging module is further operable to determine the first wellbore location
error and the second wellbore location error using the Wolfe-Dewardt ellipse of uncertainty
model.
[0032] In one or more aspects of the disclosed system, the wellbore ranging
module is further operable to receive second ranging information in response to the second
ranging measurement signal sent from the first wellbore near the determined second depth in the
first wellbore, update, based on the first ranging information, the location of the second wellbore,
update, based on the first ranging information, the second wellbore location error, and determine,
using the updated location of the first wellbore, the updated location of the second wellbore, and
the updated second wellbore location error, a third depth in the first wellbore at which to send a
third ranging measurement signal. In one or more aspects of the disclosed system, the wellbore
ranging module is further operable to generate one or more alerts.
[0033] In one or more aspects of the disclosed system, the wellbore ranging
module is further operable to generate a three-dimensional visualization comprising the
determined locations of the first wellbore and the second wellbore. In one or more aspects of the
disclosed system, the visualization further comprises the first wellbore location error and the
second wellbore location error. In one or more aspects of the disclosed system, the visualization
further comprises an axis indicator. In one or more aspects of the disclosed system, wherein the
wellbore ranging module is further operable to modify a perspective view of the visualization. In
one or more aspects of the disclosed system, the wellbore ranging module is further operable to
update the visualization periodically.
[0034] In another embodiment, a method for determining locations at which to
take a ranging measurements in a wellbore includes receiving survey information in response to
a survey measurement signal and determining, based on the survey information, a location of a
first wellbore in a formation. The method also includes receiving first ranging information in
response to a first ranging measurement signal sent from the first wellbore at a first depth in the
first wellbore and determining, based on the first ranging information, a location of a second
wellbore in the formation and a second wellbore location error associated with the determined
location of the second wellbore in the formation. The method further includes determining,
using the location of the first wellbore, the location of the second wellbore, and the second
wellbore location error, a second depth in the first wellbore at which to send a second ranging
measurement signal.
[0035] In one or more aspects of the disclosed method, the location of a second
wellbore is further based on the received survey information, and the second wellbore location
error is further based on the received survey information. In one or more aspects of the disclosed
method, the determined location of the first wellbore comprises a past trajectory of the first
wellbore in the formation, and the determined location of the second wellbore comprises a past
trajectory of the second wellbore in the formation. In one or more aspects of the disclosed
method, the determined location of the second wellbore further comprises a future trajectory of
the second wellbore in the formation, and the wellbore ranging module is further operable to
determine a future trajectory of the first wellbore based on the location of the first wellbore in the
formation and a current steering angle of the first wellbore. In one or more aspects of the
disclosed method, the wellbore ranging module is further operable to determine a first wellbore
location error associated with the future trajectory of the first wellbore, and the second wellbore
location error comprises a first portion and a second portion, the first portion being associated
with the past trajectory of the second wellbore and the second portion being associated with the
future trajectory of the second wellbore. In one or more aspects of the disclosed method, the
wellbore ranging module is further operable to determine, using the first wellbore location error
and the second wellbore location error, a location in the formation at which an intersection of the
first wellbore and the second wellbore may occur. In one or more aspects of the disclosed
method, the wellbore ranging module is further operable to determine the first wellbore location
error and the second wellbore location error using the Wolfe-Dewardt ellipse of uncertainty
model.
[0036] In one or more aspects of the disclosed method, the wellbore ranging
module is further operable to receive second ranging information in response to the second
ranging measurement signal sent from the first wellbore near the determined second depth in the
first wellbore, update, based on the first ranging information, the location of the second wellbore,
update, based on the first ranging information, the second wellbore location error, and determine,
using the updated location of the first wellbore, the updated location of the second wellbore, and
the updated second wellbore location error, a third depth in the first wellbore at which to send a
third ranging measurement signal. In one or more aspects of the disclosed method, the method
further comprises generating one or more alerts.
[0037] In one or more aspects of the disclosed method, the method further
comprises generating a three-dimensional visualization comprising the determined locations of
the first wellbore and the second wellbore. In one or more aspects of the disclosed method, the
visualization further comprises the first wellbore location error and the second wellbore location
error. In one or more aspects of the disclosed method, the visualization further comprises an axis
indicator. In one or more aspects of the disclosed method, the method further comprises
modifying a perspective view of the visualization. In one or more aspects of the disclosed
method, the method further comprises updating the visualization periodically.
[0038] In another embodiment, a computer-readable medium comprising
instructions that, when executed by a processor, cause the processor to receive survey
information in response to a survey measurement signal, and determine, based on the survey
information, a location of a first wellbore in a formation. The instructions may also cause the
processor, when executed, to receive first ranging information in response to a first ranging
measurement signal sent from the first wellbore at a first depth in the first wellbore, and
determine, based on the first ranging information, a location of a second wellbore in the
formation and a second wellbore location error associated with the determined location of the
second wellbore in the formation. The instructions may further cause the processor, when
executed, to determine, using the location of the first wellbore, the location of the second
wellbore, and the second wellbore location error, a second depth in the first wellbore at which to
send a second ranging measurement signal.
[0039] In one or more aspects of the disclosed computer-readable medium, the
location of a second wellbore is further based on the received survey information, and the second
wellbore location error is further based on the received survey information. In one or more
aspects of the disclosed computer-readable medium, the determined location of the first wellbore
comprises a past trajectory of the first wellbore in the formation, and the determined location of
the second wellbore comprises a past trajectory of the second wellbore in the formation. In one
or more aspects of the disclosed computer-readable medium, the determined location of the
second wellbore further comprises a future trajectory of the second wellbore in the formation,
and the medium further comprises instructions that, when executed by a processor, cause the
processor to determine a future trajectory of the first wellbore based on the location of the first
wellbore in the formation and a current steering angle of the first wellbore. In one or more
aspects of the disclosed computer-readable medium, the medium further comprises instructions
that, when executed by a processor, cause the processor to determine a first wellbore location
error associated with the future trajectory of the first wellbore, and the second wellbore location
error comprises a first portion and a second portion, the first portion being associated with the
past trajectory of the second wellbore and the second portion being associated with the future
trajectory of the second wellbore. In one or more aspects of the disclosed computer-readable
medium, the medium further comprises instructions that, when executed by a processor, cause
the processor to determine, using the first wellbore location error and the second wellbore
location error, a location in the formation at which an intersection of the first wellbore and the
second wellbore may occur. In one or more aspects of the disclosed computer-readable medium,
the medium further comprises instructions that, when executed by a processor, cause the
processor to determine the first wellbore location error and the second wellbore location error
using the Wolfe-Dewardt ellipse of uncertainty model.
[0040] In one or more aspects of the disclosed computer-readable medium,
receive second ranging information in response to the second ranging measurement signal sent
from the first wellbore near the determined second depth in the first wellbore, update, based on
the first ranging information, the location of the second wellbore, update, based on the first
ranging information, the second wellbore location error, and determine, using the updated
location of the first wellbore, the updated location of the second wellbore, and the updated
second wellbore location error, a third depth in the first wellbore at which to send a third ranging
measurement signal. In one or more aspects of the disclosed computer-readable medium, the
medium further comprises instructions that, when executed by a processor, cause the processor
to generate alerts.
[0041] In one or more aspects of the disclosed computer-readable medium, the
medium further comprises instructions that, when executed by a processor, cause the processor
to generate a three-dimensional visualization comprising the determined locations of the first
wellbore and the second wellbore. In one or more aspects of the disclosed computer-readable
medium, the visualization further comprises the first wellbore location error and the second
wellbore location error. In one or more aspects of the disclosed computer-readable medium, the
visualization further comprises an axis indicator. In one or more aspects of the disclosed
computer-readable medium, the medium further comprises instructions that, when executed by a
processor, cause the processor to modify a perspective view of the visualization. In one or more
aspects of the disclosed computer-readable medium, the medium further comprises instructions
that, when executed by a processor, cause the processor to update the visualization periodically.
[0042] Illustrative embodiments of the present disclosure have been described
herein. In the interest of clarity, not all features of an actual implementation may have been
described in this specification. It will of course be appreciated that in the development of any
such actual embodiment, numerous implementation-specific decisions may be made to achieve
the specific implementation goals, which may vary from one implementation to another.
Moreover, it will be appreciated that such a development effort might be complex and timeconsuming,
but would nevertheless be a routine undertaking for those of ordinary skill in the art
having the benefit of the present disclosure.
[0043] It will be understood that the terms "couple" or "couples" as used herein
are intended to mean either an indirect or a direct connection. Thus, if a first device couples to a
second device, that connection may be through a direct connection, or through an indirect
electrical or mechanical connection via other devices and connections. It will also be understood
that the terms "drilling equipment" and "drilling system" are not intended to limit the use of the
equipment and processes described with those terms to drilling an oil well. The terms will also
be understood to encompass drilling natural gas wells or hydrocarbon wells in general. Further,
such wells can be used for production, monitoring, or injection in relation to the recovery of
hydrocarbons or other materials from the subsurface. This could also include geothermal wells
intended to provide a source of heat energy instead of hydrocarbons.
[0044] To facilitate a better understanding of the present disclosure, examples of
certain embodiments have been given. In no way should the examples be read to limit, or define,
the scope of the disclosure. Embodiments of the present disclosure may be applicable to
horizontal, vertical, deviated, multilateral, u-tube connection, intersection, bypass (drill around a
mid-depth stuck fish and back into the wellbore below), or otherwise nonlinear wellbores in any
type of subterranean formation. Certain embodiments may be applicable, for example, to
logging data acquired with wireline, slickline, and logging while drilling/measurement while
drilling (LWD/MWD). Certain embodiments may be applicable to subsea and/or deep sea
wellbores. Embodiments described above with respect to one implementation are not intended to
be limiting.
[0045] Therefore, the present disclosure is well adapted to attain the ends and
advantages mentioned as well as those that are inherent therein. The particular embodiments
disclosed above are illustrative only, as the present disclosure may be modified and practiced in
different but equivalent manners apparent to those skilled in the art having the benefit of the
teachings herein. Furthermore, no limitations are intended to the details of construction or
design herein shown, other than as described in the claims below. It is therefore evident that the
particular illustrative embodiments disclosed above may be altered or modified and all such
variations are considered within the scope and spirit of the present disclosure. Also, the terms in
the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by
the patentee.

CLAIMS
What is claimed is:
1. A wellbore ranging system, comprising:
a processor;
a memory; and
a wellbore ranging module operable to:
receive survey information in response to a survey measurement signal;
determine, based on the survey information, a location of a first wellbore in a
formation;
receive first ranging information in response to a first ranging measurement signal
sent from the first wellbore at a first depth in the first wellbore;
determine, based on the first ranging information, a location of a second wellbore
in the formation;
determine, based on the first ranging information, a second wellbore location error
associated with the determined location of the second wellbore in the formation; and
determine, using the location of the first wellbore, the location of the second
wellbore, and the second wellbore location error, a second depth in the first wellbore at which to
send a second ranging measurement signal.
2. The system of Claim 1, wherein the location of a second wellbore is further based on the
received survey information, and the second wellbore location error is further based on the
received survey information.
3. The system of Claim 1, wherein:
the determined location of the first wellbore comprises a past trajectory of the first
wellbore in the formation; and
the determined location of the second wellbore comprises a past trajectory of the second
wellbore in the formation.
4. The system of Claim 3, wherein:
the determined location of the second wellbore further comprises a future trajectory of
the second wellbore in the formation; and
the wellbore ranging module is further operable to determine a future trajectory of the
first wellbore based on the location of the first wellbore in the formation and a current steering
angle of the first wellbore.
5. The system of Claim 4, wherein:
the wellbore ranging module is further operable to determine a first wellbore location
error associated with the future trajectory of the first wellbore; and
the second wellbore location error comprises a first portion and a second portion, the first
portion being associated with the past trajectory of the second wellbore and the second portion
being associated with the future trajectory of the second wellbore.
6. The system of Claim 5, wherein the wellbore ranging module is further operable to
determine, using the first wellbore location error and the second wellbore location error, a
location in the formation at which an intersection of the first wellbore and the second wellbore
may occur.
7. The system of Claim 5, wherein the wellbore ranging module is further operable to
determine the first wellbore location error and the second wellbore location error using the
Wolfe-Dewardt ellipse of uncertainty model.
8. The system of Claim 1, wherein the wellbore ranging module is further operable to
receive second ranging information in response to the second ranging measurement
signal sent from the first wellbore near the determined second depth in the first wellbore;
update, based on the first ranging information, the location of the second wellbore;
update, based on the first ranging information, the second wellbore location error; and
determine, using the updated location of the first wellbore, the updated location of the
second wellbore, and the updated second wellbore location error, a third depth in the first
wellbore at which to send a third ranging measurement signal.
9. The system of any one of Claims 1-8, wherein the wellbore ranging module is further
operable to generate one or more alerts.
10. The system of any one of Claims 1-8, wherein the wellbore ranging module is further
operable to generate a three-dimensional visualization comprising the determined locations of
the first wellbore and the second wellbore.
11. The system of Claim 10, wherein the visualization further comprises the first wellbore
location error and the second wellbore location error.
12. The system of Claim 10, wherein the visualization further comprises an axis indicator.
13. The system of Claim 10, wherein the wellbore ranging module is further operable to
modify a perspective view of the visualization.
14. The system of Claim 10, wherein the wellbore ranging module is further operable to
update the visualization periodically.
15. A method for determining locations at which to take a ranging measurements in a
wellbore, comprising:
receiving survey information in response to a survey measurement signal;
determining, based on the survey information, a location of a first wellbore in a
formation;
receiving first ranging information in response to a first ranging measurement signal sent
from the first wellbore at a first depth in the first wellbore;
determining, based on the first ranging information, a location of a second wellbore in the
formation;
determining, based on the first ranging information, a second wellbore location error
associated with the determined location of the second wellbore in the formation; and
determining, using the location of the first wellbore, the location of the second wellbore,
and the second wellbore location error, a second depth in the first wellbore at which to send a
second ranging measurement signal.
16. The method of Claim 15, wherein the location of a second wellbore is further based on
the received survey information, and the second wellbore location error is further based on the
received survey information.
17. The method of Claim 15, wherein:
the determined location of the first wellbore comprises a past trajectory of the first
wellbore in the formation; and
the determined location of the second wellbore comprises a past trajectory of the second
wellbore in the formation.
18. The method of Claim 17, wherein:
the determined location of the second wellbore further comprises a future trajectory of
the second wellbore in the formation; and
the method further comprises determining a future trajectory of the first wellbore based
on the location of the first wellbore in the formation and a current steering angle of the first
wellbore.
19. The method of Claim 18, wherein:
the method further comprises determining a first wellbore location error associated with
the future trajectory of the first wellbore; and
the second wellbore location error comprises a first portion and a second portion, the first
portion being associated with the past trajectory of the second wellbore and the second portion
being associated with the future trajectory of the second wellbore.
20. The method of Claim 19, wherein the method further comprises determining, using the
first wellbore location error and the second wellbore location error, a location in the formation at
which an intersection of the first wellbore and the second wellbore may occur.
2 1. The method of Claim 19, wherein the method further comprises determining the first
wellbore location error and the second wellbore location error using the Wolfe-Dewardt ellipse
of uncertainty model.
22. The method of Claim 15, wherein the method further comprises:
receiving second ranging information in response to the second ranging measurement
signal sent from the first wellbore near the determined second depth in the first wellbore;
updating, based on the first ranging information, the location of the second wellbore;
updating, based on the first ranging information, the second wellbore location error; and
determining, using the updated location of the first wellbore, the updated location of the
second wellbore, and the updated second wellbore location error, a third depth in the first
wellbore at which to send a third ranging measurement signal.
23. The method of any one of Claims 15-22, further comprising generating one or more
alerts.
24. The method of any one of Claims 15-22, further comprising generating a threedimensional
visualization comprising the determined locations of the first wellbore and the
second wellbore.
25. The method of Claim 24, wherein the visualization further comprises the first wellbore
location error and the second wellbore location error.
26. The method of Claim 24, wherein the visualization further comprises an axis indicator.
27. The method of Claim 24, further comprising modifying a perspective view of the
visualization.
28. The method of Claim 24, further comprising updating the visualization periodically.
29. A computer-readable medium comprising instructions that, when executed by a
processor, cause the processor to:
receive survey information in response to a survey measurement signal;
determine, based on the survey information, a location of a first wellbore in a formation;
receive first ranging information in response to a first ranging measurement signal sent
from the first wellbore at a first depth in the first wellbore;
determine, based on the first ranging information, a location of a second wellbore in the
formation;
determine, based on the first ranging information, a second wellbore location error
associated with the determined location of the second wellbore in the formation; and
determine, using the location of the first wellbore, the location of the second wellbore,
and the second wellbore location error, a second depth in the first wellbore at which to send a
second ranging measurement signal.
30. The computer-readable medium of Claim 29, wherein the location of a second wellbore is
further based on the received survey information, and the second wellbore location error is
further based on the received survey information.
31. The computer-readable medium of Claim 29, wherein:
the determined location of the first wellbore comprises a past trajectory of the first
wellbore in the formation; and
the determined location of the second wellbore comprises a past trajectory of the second
wellbore in the formation.
32. The computer-readable medium of Claim 1, wherein:
the determined location of the second wellbore further comprises a future trajectory of
the second wellbore in the formation; and
the medium further comprises instructions that, when executed by a processor, cause the
processor to determine a future trajectory of the first wellbore based on the location of the first
wellbore in the formation and a current steering angle of the first wellbore.
33. The computer-readable medium of Claim 32, wherein:
the medium further comprises instructions that, when executed by a processor, cause the
processor to determine a first wellbore location error associated with the future trajectory of the
first wellbore; and
the second wellbore location error comprises a first portion and a second portion, the first
portion being associated with the past trajectory of the second wellbore and the second portion
being associated with the future trajectory of the second wellbore.
34. The computer-readable medium of Claim 33, wherein the medium further comprises
instructions that, when executed by a processor, cause the processor to determine, using the first
wellbore location error and the second wellbore location error, a location in the formation at
which an intersection of the first wellbore and the second wellbore may occur.
35. The computer-readable medium of Claim 33, further comprising instructions that, when
executed by a processor, cause the processor to determine the first wellbore location error and
the second wellbore location error using the Wolfe-Dewardt ellipse of uncertainty model.
36. The computer-readable medium of Claim 29, further comprising instructions that are
operable to cause a processor to:
receive second ranging information in response to the second ranging measurement
signal sent from the first wellbore near the determined second depth in the first wellbore;
update, based on the first ranging information, the location of the second wellbore;
update, based on the first ranging information, the second wellbore location error; and
determine, using the updated location of the first wellbore, the updated location of the
second wellbore, and the updated second wellbore location error, a third depth in the first
wellbore at which to send a third ranging measurement signal.
37. The computer-readable medium of any one of Claims 29-36, further comprising
instructions that, when executed by a processor, cause the processor to generate alerts.
38. The computer-readable medium of any one of Claims 29-36, further comprising
instructions that, when executed by a processor, cause the processor to generate a threedimensional
visualization comprising the determined locations of the first wellbore and the
second wellbore.
39. The computer-readable medium of Claim 38, wherein the visualization further comprises
the first wellbore location error and the second wellbore location error.
40. The computer-readable medium of Claim 38, wherein the visualization further comprises
an axis indicator.
4 1. The computer-readable medium of Claim 38, further comprising instructions that, when
executed by a processor, cause the processor to modify a perspective view of the visualization.
42. The computer-readable medium of Claim 38, further comprising instructions that, when
executed by a processor, cause the processor to update the visualization periodically.