In-well microseism event positioning method, electronic equipment, storage medium and device
By performing three-component polarization analysis on microseismic events in wells, the angle of wave propagation direction and the coordinates of the geophone are obtained, solving the accuracy and cost problems of microseismic location in wells in existing technologies, and realizing rapid and accurate microseismic event location.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2026-03-24
AI Technical Summary
Existing well microseismic location methods are insufficient in terms of accuracy and cost, especially in real-time fracturing monitoring where it is difficult to quickly and accurately identify and locate microseismic events.
By performing horizontal and vertical polarization analysis on the three-component data of microseismic monitoring from three wells, the horizontal and vertical azimuth angles of the P-wave propagation direction are obtained. Combined with the geophone coordinates and the wave propagation ray path, the spatial coordinates of the microseismic event are calculated, enabling rapid location.
Rapid location of microseismic events in the well can be achieved without the need for initial arrival time, improving positioning accuracy and reducing costs.
Smart Images
Figure CN121721731A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of geophysical exploration technology, and more specifically, relates to a method for locating microseismic events in wells, electronic equipment, storage medium, and device. Background Technology
[0002] Microseismic fracturing monitoring technology has now become a commonly used monitoring technique in the development of tight reservoir oil and gas fields. As early as the 1970s and 80s, microseismic technology was already a common method in fields such as mine disaster monitoring and geothermal development. Since the beginning of the 21st century, due to the rapid development of unconventional oil and gas, especially shale gas, microseismic technology has played an important role in optimizing fracturing schemes and well network deployment, enabling the rapid development of microseismic monitoring technology in oil and gas field development.
[0003] Borehole microseismic monitoring is one of the methods for monitoring microseismic events. Borehole observation involves deploying multiple geophones in wells near the target area to monitor microseismic signals. Its data characteristics include: three-component reception; random and chaotic amplitude and polarity between components; a large number of valid events; and the presence of both P-waves and S-waves in the seismic phases. Localization of microseismic events in wells is one of the key technologies for processing microseismic events in wells. The main methods for well-drilled microseismic location include: First, forward modeling based on P-wave and S-wave event travel times, with representative algorithms such as network search, simulated annealing, and Geiger method. The advantage is that it is easy to implement, but the disadvantage is that it is difficult to accurately pick up the P-wave and S-wave travel times of microseismic events, affecting the location results. Second, wave equation convolution, with representative algorithms such as interferometry, reverse time migration, and passive source imaging. The advantage is that it does not require picking up the first arrival of events, but the disadvantage is that it requires high signal-to-noise ratio and velocity model of the data, a large number of detectors, and high computational cost. Third, the difference between anisotropic and isotropic travel time calculations. In anisotropic media, the error of isotropic travel time calculation is larger, and the corresponding location error is also larger.
[0004] To provide real-time descriptions of the dynamic progression of artificial fractures generated by hydraulic fracturing, and to aid in the evaluation of fracturing effectiveness and the rational deployment of development well networks, the development of real-time microseismic processing systems has become a hot topic. This requires the rapid identification and localization of events from microseismic data within a very short timeframe. Traditional identification and processing methods would obviously increase time costs. Therefore, it is necessary to develop a new technology to meet the diverse needs of real-time processing.
[0005] The information disclosed in the background section of this invention is intended only to enhance the understanding of the general background of this invention and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Summary of the Invention
[0006] The purpose of this invention is to propose a method, electronic device, storage medium, and apparatus for locating microseismic events in wells, which enables the calculation of the spatial coordinates of microseismic events using only three-component polarization analysis without requiring the initial arrival travel time of the microseismic event, thus achieving rapid location of microseismic events in wells.
[0007] To achieve the above objectives, the present invention proposes a method for locating microseismic events in wells, an electronic device, a storage medium, and a device.
[0008] According to a first aspect of the present invention, a method for locating microseismic events in a well is proposed, comprising:
[0009] Based on the three-component microseismic monitoring data of the three wells, horizontal polarization analysis and vertical polarization analysis were carried out successively to obtain the horizontal azimuth and vertical azimuth of the P-wave propagation direction of each well.
[0010] The horizontal plane location coordinates of microseismic events are calculated based on the horizontal azimuth angle and the horizontal plane coordinates of the geophone for each well.
[0011] The vertical depth coordinates of the microseismic event are calculated based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth of each well.
[0012] The well-hole microseismic event location is completed based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic event.
[0013] Optionally, obtaining the horizontal azimuth angle of the P-wave propagation direction for each well includes:
[0014] Establish a mutually perpendicular coordinate system YX for each well, with the X component direction as the horizontal axis and the Y component direction as the vertical axis. Plot the connection diagram of the microseismic event signal data of the X component and Y component in chronological order. Obtain the first azimuth linear equation by fitting the linear characteristics.
[0015] The horizontal azimuth angle of the P-wave propagation direction in the YX plane of the coordinate system is calculated based on the first azimuth linear equation.
[0016] Optionally, obtaining the vertical azimuth angle of the P-wave propagation direction for each well includes:
[0017] Based on the horizontal azimuth angle of each well, the microseismic event signal data of their respective X and Y components are rotated to obtain the R component along the P-wave propagation direction and the T component perpendicular to the P-wave propagation direction of each well.
[0018] Establish a mutually perpendicular coordinate system RZ for the R component and vertical component Z of each well. With the direction of the Z component as the horizontal axis and the direction of the R component as the vertical axis, draw a line diagram connecting the microseismic event signal data of the R component and Z component in chronological order. Obtain the second azimuth linear equation by fitting the linear characteristics.
[0019] The vertical azimuth angle of the P-wave propagation direction in the RZ plane of the coordinate system is calculated based on the second azimuth linear equation.
[0020] Optionally, the calculation of the horizontal plane positioning coordinates of the microseismic event based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone includes:
[0021] Construct three straight lines in the horizontal plane of the YX coordinate system to indicate the direction of P-wave propagation.
[0022] Obtain the detector horizontal plane coordinates of each straight line passing through the corresponding detector on the YX horizontal plane of the coordinate system;
[0023] The coordinates of the intersection points of the three straight lines are calculated based on the horizontal azimuth angle of each well and the corresponding horizontal plane coordinates of the detector.
[0024] The average of the x and y coordinates of the three intersection points is the horizontal plane location coordinate of the microseismic event.
[0025] Optionally, calculating the vertical depth coordinates of the microseismic event based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth angle of each well includes:
[0026] Based on the vertical azimuth angle of each well, the horizontal plane coordinates of the geophone, and the formation velocity, the transmission angle of each formation between the geophone location in each well and the formation of the microseismic event is calculated using Snell's law.
[0027] Wherein, the vertical azimuth angle of each well is the transmission angle of the formation where the corresponding geophone is located;
[0028] The length of the horizontal segment of the first transducer P-wave propagation ray path from the stratum where the corresponding geophone is located to the stratum above the stratum of the microseismic event is calculated based on the transmission angle of each well.
[0029] Calculate the total horizontal distance from the location of the microseismic event to the detector based on the horizontal plane positioning coordinates of the microseismic event;
[0030] The length of the second P-wave propagation path of the geophone is calculated based on the total horizontal distance and the length of the horizontal segment of the first geophone P-wave propagation ray path.
[0031] The thickness of the stratum where the microseismic event is located in each well is calculated based on the transmission angle of the stratum where the microseismic event is located and the length of the horizontal segment of the P-wave propagation path through the second detector.
[0032] The vertical depth coordinates of the microseismic event in each well are calculated based on the geophone depth coordinates of each well and the thickness of each stratum from the geophone location to the seismic event location.
[0033] The average value of the vertical depth coordinates of the microseismic events in the three wells is used to determine the vertical depth coordinates of the microseismic events.
[0034] Optionally, the linear equation for the first azimuth angle is:
[0035] y i,j =tgα i *x i,j +b i ;
[0036] Where, α i The angle between the direction of P-wave propagation in the i-th well and the X component in the YX plane of the coordinate system represents the horizontal azimuth angle of the direction of P-wave propagation in the i-th well in the YX plane of the coordinate system. i,j For X component monitoring data, y i,j For Y component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, b i Let be the intercept of the linear equation for the first azimuth angle of the i-th well.
[0037] Optionally, the second azimuth linear equation is:
[0038] R i,j =tgβ i *z i,j +c i ;
[0039] Where, β i The angle between the propagation direction of the P-wave in the i-th well and the X component on the RZ plane of the coordinate system is the horizontal azimuth angle of the propagation direction of the P-wave in the i-th well on the RZ plane of the coordinate system. i,j For Z component monitoring data, R i,j For R-component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, c i Let be the intercept of the linear equation for the second azimuth angle of the i-th well.
[0040] According to a second aspect of the present invention, a well microseismic event location device is provided, comprising:
[0041] The polarization analysis module is used to perform horizontal polarization analysis and vertical polarization analysis based on the three components of microseismic monitoring data from each of the three wells, and to obtain the horizontal and vertical azimuth angles of the P-wave propagation direction of each well.
[0042] The first calculation module is used to calculate the horizontal plane positioning coordinates of microseismic events based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone.
[0043] The second calculation module is used to calculate the vertical depth positioning coordinates of the microseismic event based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth angle of each well.
[0044] The positioning module is used to locate microseismic events in the well based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic events.
[0045] According to a third aspect of the present invention, an electronic device is provided, the electronic device comprising:
[0046] At least one processor; and,
[0047] A memory communicatively connected to the at least one processor; wherein,
[0048] The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the well microseismic event localization method according to any of the first aspects.
[0049] According to a fourth aspect of the invention, a non-transitory computer-readable storage medium is provided, which stores computer instructions for causing a computer to perform the well microseismic event localization method described in any of the first aspects.
[0050] The beneficial effects of this invention are as follows: This invention obtains the horizontal and vertical azimuth angles of wave propagation direction by performing three-component polarization analysis on three wells under the same microseismic event. Combined with the geophone coordinates and wave propagation ray path, the spatial coordinates of the microseismic event can be calculated without the initial arrival time of the microseismic event, thereby realizing rapid location of microseismic events in wells, improving positioning accuracy, and reducing costs.
[0051] The system of the present invention has other features and advantages that will be apparent from or will be set forth in detail in the accompanying drawings and following detailed description, which together serve to explain the particular principles of the invention. Attached Figure Description
[0052] The above and other objects, features and advantages of the present invention will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.
[0053] Figure 1 A flowchart illustrating the steps of a well microseismic event localization method according to the present invention is shown.
[0054] Figure 2 A flowchart illustrating the steps of a well microseismic event localization method according to Embodiment 2 of the present invention is shown.
[0055] Figure 3 a and Figure 3 b shows a depth side view and a horizontal top view of the theoretical model for joint monitoring of three wells according to Embodiment 2 of the present invention.
[0056] Figure 4 A schematic diagram of horizontal location of intersecting microseismic events based on horizontal azimuth angle is shown according to Embodiment 2 of the present invention.
[0057] Figure 5 A schematic diagram of ray path microseismic event depth localization based on vertical azimuth angle according to Embodiment 2 of the present invention is shown.
[0058] Figure 6 a and Figure 6 b shows a depth side view and a horizontal top view of the well microseismic event localization results according to Embodiment 2 of the present invention. Detailed Implementation
[0059] The invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0060] like Figure 1 As shown, a well microseismic event localization method according to the present invention includes:
[0061] Based on the three-component microseismic monitoring data of the three wells, horizontal polarization analysis and vertical polarization analysis were carried out successively to obtain the horizontal azimuth and vertical azimuth of the P-wave propagation direction of each well.
[0062] Calculate the horizontal plane location coordinates of microseismic events based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone.
[0063] The vertical depth coordinates of microseismic events are calculated based on the horizontal plane positioning coordinates of the microseismic events and the vertical azimuth of each well.
[0064] The well-hole microseismic event location was completed based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic event.
[0065] Specifically, given the known Z, X, and Y components of microseismic monitoring data from three wells, polarization analysis is performed on the X and Y components of the microseismic event data from each well using the P-wave particle polarization principle. This yields the horizontal azimuth angle of the P-wave propagation direction in the X and Y component planes of the coordinate system. The X and Y components are then rotated to obtain two new components: the R component along the wave propagation direction in the horizontal plane and the T component perpendicular to the wave propagation direction. Similarly, polarization analysis is performed on the Z and R component data from each well to obtain the vertical azimuth angle of the P-wave propagation direction in the Z and R component planes of the coordinate system. The second step utilizes the horizontal azimuth angle of the P-wave propagation direction in the X and Y component planes of the coordinate system from the first step. The invention employs a three-component polarization analysis method to determine the location of microseismic events. First, by combining the horizontal coordinates of the geophones in each well with the horizontal plane coordinates, three straight lines passing through the geophones are constructed in the horizontal plane. The coordinates of the three intersecting points are calculated, and the average coordinates are then calculated to obtain the horizontal plane location result for the microseismic event. Second, using the vertical azimuth angles of the P-wave propagation direction in the Z and R component planes of the three wells from the first step, and given the geophone coordinates and formation velocity, Snell's law is used to obtain the vertical ray paths of the three wells. Combined with the horizontal plane location result from the second step, the corresponding depths along the wave propagation ray paths of the three wells are calculated, and their average value is calculated to obtain the vertical depth location result for the microseismic event. This ultimately achieves the spatial location of the microseismic event. The invention obtains the horizontal and vertical azimuth angles of the wave propagation direction by performing three-component polarization analysis on three wells under the same microseismic event. Combined with the geophone coordinates and wave propagation ray paths, the spatial coordinates of the microseismic event can be calculated without the initial arrival time, enabling rapid location of microseismic events in wells, improving positioning accuracy, and reducing costs.
[0066] In one example, obtaining the horizontal azimuth of the P-wave propagation direction for each well includes:
[0067] Establish a mutually perpendicular coordinate system YX for each well, with the X component direction as the horizontal axis and the Y component direction as the vertical axis. Plot the connection diagram of the microseismic event signal data of the X component and Y component in chronological order. Obtain the first azimuth linear equation by fitting the linear characteristics.
[0068] The horizontal azimuth angle of the P-wave propagation direction in the YX plane of the coordinate system for each well is calculated based on the first azimuth angle linear equation.
[0069] In one example, obtaining the vertical azimuth of the P-wave propagation direction for each well includes:
[0070] Based on the horizontal azimuth angle of each well, the microseismic event signal data of their respective X and Y components are rotated to obtain the R component along the P-wave propagation direction and the T component perpendicular to the P-wave propagation direction of each well.
[0071] Establish a mutually perpendicular coordinate system RZ for the R component and vertical component Z of each well. With the direction of the Z component as the horizontal axis and the direction of the R component as the vertical axis, draw a line diagram connecting the microseismic event signal data of the R component and Z component in chronological order. Obtain the second azimuth linear equation by fitting the linear characteristics.
[0072] The vertical azimuth angle of the P-wave propagation direction in the RZ plane of the coordinate system is calculated based on the second azimuth linear equation.
[0073] In one example, calculating the horizontal plane location coordinates of microseismic events based on the horizontal azimuth of each well and the horizontal plane coordinates of the geophone includes:
[0074] Construct three straight lines in the horizontal plane of the YX coordinate system to indicate the direction of P-wave propagation.
[0075] Obtain the detector horizontal plane coordinates of each straight line passing through the corresponding detector on the YX horizontal plane of the coordinate system;
[0076] The coordinates of the intersection points of the three straight lines are calculated based on the horizontal azimuth angle of each well and the corresponding horizontal plane coordinates of the geophone.
[0077] The average of the x and y coordinates of the three intersection points is the horizontal plane location coordinate of the microseismic event.
[0078] In one example, calculating the vertical depth coordinates of a microseismic event based on its horizontal plane location coordinates and the vertical azimuth of each well includes:
[0079] Based on the vertical azimuth angle, geophone horizontal plane coordinates, and formation velocity of each well, the transmission angle between the geophone location and the formation of the microseismic event is calculated using Snell's law.
[0080] The vertical azimuth angle of each well is the transmission angle of the formation where the corresponding geophone is located;
[0081] The length of the horizontal segment of the first P-wave propagation ray path from the geophone to the stratum above the microseismic event stratum is calculated based on the transmission angle of each well.
[0082] Calculate the total horizontal distance from the location of the microseismic event to the detector based on the horizontal plane positioning coordinates of the microseismic event;
[0083] The length of the second P-wave propagation path of the geophone is calculated based on the total horizontal distance and the length of the horizontal segment of the first geophone P-wave propagation ray path.
[0084] The thickness of the stratum where the microseismic event is located in each well is calculated based on the transmission angle of the stratum where the microseismic event is located and the length of the horizontal segment of the P-wave propagation path through the second detector.
[0085] The vertical depth coordinates of the microseismic event in each well are calculated based on the geophone depth coordinates of each well and the thickness of each stratum from the geophone location to the seismic event location.
[0086] The average value of the vertical depth coordinates of the microseismic events in the three wells is used to determine the vertical depth coordinates of the microseismic events.
[0087] In one example, the linear equation for the first azimuth angle is:
[0088] y i,j =tgα i *x i,j +b i ;
[0089] Where, α i The angle between the direction of P-wave propagation in the i-th well and the X component in the YX plane of the coordinate system represents the horizontal azimuth angle of the direction of P-wave propagation in the i-th well in the YX plane of the coordinate system. i,j For X component monitoring data, y i,j For Y component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, b i Let be the intercept of the linear equation for the first azimuth angle of the i-th well.
[0090] In one example, the linear equation for the second azimuth angle is:
[0091] R i,j =tgβ i *z i,j +c i ;
[0092] Where, β i The angle between the propagation direction of the P-wave in the i-th well and the X component on the RZ plane of the coordinate system is the horizontal azimuth angle of the propagation direction of the P-wave in the i-th well on the RZ plane of the coordinate system. i,j For Z component monitoring data, R i,j For R-component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, c i Let be the intercept of the linear equation for the second azimuth angle of the i-th well.
[0093] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the invention. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other.
[0094] Example 1
[0095] This embodiment provides a method for locating microseismic events in a well, including:
[0096] Based on the three-component microseismic monitoring data of the three wells, horizontal polarization analysis and vertical polarization analysis were carried out successively to obtain the horizontal azimuth and vertical azimuth of the P-wave propagation direction of each well.
[0097] Calculate the horizontal plane location coordinates of microseismic events based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone.
[0098] The vertical depth coordinates of microseismic events are calculated based on the horizontal plane positioning coordinates of the microseismic events and the vertical azimuth of each well.
[0099] The well-hole microseismic event location was completed based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic event.
[0100] Obtaining the horizontal azimuth angle of the P-wave propagation direction for each well includes:
[0101] Establish a mutually perpendicular coordinate system YX for each well, with the X component direction as the horizontal axis and the Y component direction as the vertical axis. Plot the connection diagram of the microseismic event signal data of the X component and Y component in chronological order. Obtain the first azimuth linear equation by fitting the linear characteristics.
[0102] The horizontal azimuth angle of the P-wave propagation direction in the YX plane of the coordinate system for each well is calculated based on the first azimuth angle linear equation.
[0103] Obtaining the vertical azimuth angle of the P-wave propagation direction for each well includes:
[0104] Based on the horizontal azimuth angle of each well, the microseismic event signal data of their respective X and Y components are rotated to obtain the R component along the P-wave propagation direction and the T component perpendicular to the P-wave propagation direction of each well.
[0105] Establish a mutually perpendicular coordinate system RZ for the R component and vertical component Z of each well. With the direction of the Z component as the horizontal axis and the direction of the R component as the vertical axis, draw a line diagram connecting the microseismic event signal data of the R component and Z component in chronological order. Obtain the second azimuth linear equation by fitting the linear characteristics.
[0106] The vertical azimuth angle of the P-wave propagation direction in the RZ plane of the coordinate system is calculated based on the second azimuth linear equation.
[0107] The horizontal plane location coordinates of microseismic events are calculated based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone, including:
[0108] Construct three straight lines in the horizontal plane of the YX coordinate system to indicate the direction of P-wave propagation.
[0109] Obtain the detector horizontal plane coordinates of each straight line passing through the corresponding detector on the YX horizontal plane of the coordinate system;
[0110] The coordinates of the intersection points of the three straight lines are calculated based on the horizontal azimuth angle of each well and the corresponding horizontal plane coordinates of the geophone.
[0111] The average of the x and y coordinates of the three intersection points is the horizontal plane location coordinate of the microseismic event.
[0112] The calculation of vertical depth coordinates for microseismic events based on horizontal plane location coordinates and vertical azimuth angles of each well includes:
[0113] Based on the vertical azimuth angle, geophone horizontal plane coordinates, and formation velocity of each well, the transmission angle between the geophone location and the formation of the microseismic event is calculated using Snell's law.
[0114] The vertical azimuth angle of each well is the transmission angle of the formation where the corresponding geophone is located;
[0115] The length of the horizontal segment of the first P-wave propagation ray path from the geophone to the stratum above the microseismic event stratum is calculated based on the transmission angle of each well.
[0116] Calculate the total horizontal distance from the location of the microseismic event to the detector based on the horizontal plane positioning coordinates of the microseismic event;
[0117] The length of the second P-wave propagation path of the geophone is calculated based on the total horizontal distance and the length of the horizontal segment of the first geophone P-wave propagation ray path.
[0118] The thickness of the stratum where the microseismic event is located in each well is calculated based on the transmission angle of the stratum where the microseismic event is located and the length of the horizontal segment of the P-wave propagation path through the second detector.
[0119] The vertical depth coordinates of the microseismic event in each well are calculated based on the geophone depth coordinates of each well and the thickness of each stratum from the geophone location to the seismic event location.
[0120] The average value of the vertical depth coordinates of the microseismic events in the three wells is used to determine the vertical depth coordinates of the microseismic events.
[0121] The linear equation for the first azimuth angle is:
[0122] y i,j =tgα i *x i,j +b i ;
[0123] Where, α i The angle between the direction of P-wave propagation in the i-th well and the X component in the YX plane of the coordinate system represents the horizontal azimuth angle of the direction of P-wave propagation in the i-th well in the YX plane of the coordinate system. i,j For X component monitoring data, y i,j For Y component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, b i Let be the intercept of the linear equation for the first azimuth angle of the i-th well.
[0124] The linear equation for the second azimuth angle is:
[0125] R i,j =tgβ i *z i,j +c i ;
[0126] Where, β i The angle between the propagation direction of the P-wave in the i-th well and the X component on the RZ plane of the coordinate system is the horizontal azimuth angle of the propagation direction of the P-wave in the i-th well on the RZ plane of the coordinate system. i,j For Z component monitoring data, R i,j For R-component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, c i Let be the intercept of the linear equation for the second azimuth angle of the i-th well.
[0127] Example 2
[0128] like Figure 2 As shown, this embodiment provides a method for locating microseismic events in a well, including:
[0129] The first step involves using the known Z, X, and Y components of microseismic monitoring data from three wells. Utilizing the P-wave particle polarization principle, polarization analysis is performed on the X and Y components of the microseismic event data from each well to obtain the horizontal azimuth angle of the P-wave propagation direction in the X and Y component planes of the coordinate system. Then, the X and Y components are rotated to obtain two new components: the R component along the propagation direction in the horizontal plane and the T component perpendicular to the propagation direction. Similarly, polarization analysis is performed on the Z and R component data from each well to obtain the vertical azimuth angle of the P-wave propagation direction in the Z and R component planes of the coordinate system. The second step utilizes the horizontal azimuth angles of the P-wave propagation direction from the three wells obtained in the first step in the X and Y component planes of the coordinate system. First, combining the horizontal plane coordinates of the geophones in each well, three straight lines passing through the geophones are constructed in the horizontal plane. The coordinates of the three intersection points are calculated, and then the average coordinates are calculated, which is the horizontal plane positioning result of the microseismic event. Second, using the vertical azimuth angle of the P-wave propagation direction of the three wells in the Z and R component planes of the coordinate system from the first step, and given the geophone coordinates and formation velocity, Snell's law is used to obtain the vertical ray paths of the three wells. Then, combining the horizontal plane positioning result of the microseismic event from the second step, the corresponding depths on the wave propagation ray paths of the three wells are calculated, and their average values are calculated, which is the vertical depth positioning result of the microseismic event, thus finally achieving the spatial positioning of the microseismic event.
[0130] First, based on the known microseismic monitoring data of the three components Z, X, and Y of the wells, horizontal and vertical polarization analyses were performed sequentially to obtain the horizontal and vertical azimuth angles of the P-wave propagation direction for each well. The known microseismic P-wave Z, X, and Y component monitoring data (z... i,j ,x i,j ,y i,j (i = 1, 2, 3 represent the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sample points);
[0131] Taking the first monitoring well as an example, a mutually perpendicular coordinate system YX is established, with the X component direction as the horizontal axis and the Y component direction as the vertical axis. The microseismic event signal data (x, y, y) are plotted in chronological order. 1,j ,y 1,j The line graph, also known as the vector curve graph, has linear characteristics and is fitted with a linear equation for an azimuth angle.
[0132] y i,j =tgα i *x i,j +b i ;
[0133] Where α1 represents the angle between the wave propagation direction and the X component in the YX plane of the coordinate system, which is the horizontal azimuth angle of the P-wave propagation direction in the YX plane of the first well. The magnitude of angle α1 can be calculated using conventional linear fitting. iLet be the intercept of the linear equation for the first azimuth angle of the i-th well.
[0134] Using the horizontal azimuth angle α1, the original microseismic event signal data (x) of the first well were analyzed. 1,j ,y 1,j The rotation process is performed to obtain the two new components R and T of the first well:
[0135]
[0136] Where 1 represents the first well, j = 1, 2, ..., N, and N is the total number of sample points. The R component direction is the wave propagation direction on the YX plane of the coordinate system, and the T component direction is the vertical wave propagation direction on the YX plane of the coordinate system.
[0137] Then establish a mutually perpendicular coordinate system RZ, with the Z component direction as the horizontal axis and the R component direction as the vertical axis, and plot the microseismic event signal data (z) in chronological order. 1,j ,R 1,j Based on the linear characteristics, another linear equation for the azimuth angle is fitted to the line graph:
[0138] R i,j =tgβ i *z i,j +c i ;
[0139] Where β1 represents the angle between the wave propagation direction and the Z component on the RZ plane of the coordinate system, which is the vertical azimuth angle of the P-wave propagation direction. The magnitude of angle β1 can be calculated using conventional linear fitting. i Let be the intercept of the linear equation for the second azimuth angle of the i-th well.
[0140] The same operation process can be used to obtain the horizontal azimuth (denoted as α2 and α3) and vertical azimuth (denoted as β2 and β3) of the P-wave propagation direction of the other two wells.
[0141] Then, using the calculated horizontal azimuth angles of the three wells, the horizontal location of microseismic events was carried out.
[0142] Construct three straight lines in the horizontal plane representing the P-wave propagation direction. Calculate the coordinates of the intersection points of each pair of these lines. This is done by establishing three corresponding detectors on the horizontal plane (with the detector's horizontal coordinates (Cx)). i Cy i (i = 1, 2, 3 represent the serial numbers of the three wells) Solve for the equation of the straight line:
[0143]
[0144] By combining the pairwise intersections of the equations, the coordinates of the three intersection points (x, y, y) can be calculated. *i ,y * i (i = 1, 2, 3 represent the serial numbers of the three wells).
[0145] Then calculate its average value:
[0146] event x =(x * 1+x * 2+x * 3) / 3;
[0147] event y =(y * 1+y * 2+y * 3) / 3;
[0148] Among them, horizontal plane coordinates (event) x ,event y This refers to the horizontal location result of the microseismic event.
[0149] Finally, using the vertical azimuth angle of the P-wave propagation direction, combined with the known detector depth and formation velocity, and based on Snell's law, the ray path through the detector was obtained, and the depth of the ray path corresponding to the three wells was calculated, thereby realizing the spatial location of microseismic events.
[0150] Taking the first well as an example, the velocity V from the detector to the target layer is known. k (k = 1, 2, ..., M represents the strata number from shallow to deep), assuming the strata are a homogeneous medium, according to Snell's law:
[0151]
[0152] Where, θ k Let θ1 be the transmission angle (or incident angle) of the k-th layer (k = 1, 2, ..., M represents the strata number from shallow to deep), and the first layer is the stratum where the detector is located. Its transmission angle θ1 is equal to the vertical azimuth angle β1 of the P-wave propagation direction of the first well calculated in claim 2. That is, the transmission angles θ1 of the remaining strata can be calculated using Snell's law. k (k = 2, 3, ..., M).
[0153] Furthermore, since the depth of the microseismic events is unknown, and the thickness of the remaining strata is H... k (k = 1, 2, ..., M-1 represents the strata number from shallow to deep) is known. Using the transmission angle of each layer, starting from the first layer, the horizontal segment length of the wave propagation ray path from layer 1 to layer M-1 is calculated:
[0154] L k =H k *tgθk ;
[0155] Among them, L k This represents the horizontal segment of the ray path in the k-th layer (k = 1, 2, ..., M-1 represents the stratum number from shallow to deep).
[0156] Based on the calculated horizontal location results of microseismic events (event) x ,event y This allows us to calculate the total horizontal distance from the event to the detector.
[0157]
[0158] This allows us to determine the length L of the horizontal segment of the wave propagation ray path in the Mth layer, i.e., the layer where the event is located. M :
[0159]
[0160] Then, using the previously calculated transmission angle θ of the Mth layer... M Calculate the event layer propagation thickness H M :
[0161] H M =L M / tgθ M ;
[0162] By combining the thicknesses of layers 1 to M-1 and the geophone depth coordinate Cz1, the depth direction location of the microseismic event in the first well can be calculated:
[0163]
[0164] Using the same procedure, the depth coordinates z of the microseismic events in the other two wells were calculated. * 2, z * 3. Then calculate the average value as the final depth location result of the microseismic event. z :
[0165] event z =(z * 1+z * 2+z * 3) / 3;
[0166] Combined with the calculated horizontal location results of microseismic events (event) x ,event y This means ultimately achieving spatial localization of microseismic events. x ,event y ,event z ).
[0167] Figure 3 a and Figure 3 b illustrates the theoretical model for the joint monitoring of three wells, which includes nine microseismic events and three sets of downhole three-component geophones. First, using the P-wave particle vibration polarization principle, spatial polarization analysis is performed on the three-component data of the three wells containing the microseismic events. The horizontal and vertical azimuth angles of the microseismic events are obtained by using the vector curve-fitting straight line method in both the horizontal and vertical directions. Then, using the horizontal azimuth angle, three straight lines passing through the geophones from the same microseismic event are established, such as... Figure 4 As shown, the horizontal location of the microseismic event was calculated by solving three sets of equations. Finally, using the vertical azimuth and known layer velocity, the wave propagation paths of the microseismic events in the three wells were obtained through Snell's law, as shown. Figure 5 This allows for the calculation of the event depth, ultimately achieving spatial localization of microseismic events, such as... Figure 6 a and Figure 6 As shown in b.
[0168] As shown in Table 1, the microseismic event location error analysis of this invention shows that the location error is small. This indicates that this invention does not require picking the first arrival travel time of the microseismic event. It only uses three-component spatial polarization analysis to obtain the horizontal and vertical azimuth angles of wave propagation. Combined with the detector coordinates and the wave propagation ray path, the spatial coordinates of the microseismic event can be calculated. This demonstrates that this invention is simple, practical and has a good location effect.
[0169] Table 1 Event Location Error Statistics Table
[0170]
[0171]
[0172] Example 3
[0173] This embodiment provides a well-drilled microseismic event location device, including:
[0174] The polarization analysis module is used to perform horizontal polarization analysis and vertical polarization analysis based on the three components of microseismic monitoring data from each of the three wells, and to obtain the horizontal and vertical azimuth angles of the P-wave propagation direction of each well.
[0175] The first calculation module is used to calculate the horizontal plane positioning coordinates of microseismic events based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone.
[0176] The second calculation module is used to calculate the vertical depth coordinates of microseismic events based on the horizontal plane positioning coordinates of the microseismic events and the vertical azimuth of each well.
[0177] The positioning module is used to locate microseismic events in the well based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic events.
[0178] Example 4
[0179] This disclosure also provides an electronic device, which includes:
[0180] At least one processor; and,
[0181] A memory communicatively connected to the at least one processor; wherein,
[0182] The memory stores instructions that can be executed by the at least one processor, which enables the at least one processor to perform the well microseismic event localization method in Embodiment 1.
[0183] An electronic device according to embodiments of the present disclosure includes a memory and a processor. The memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.
[0184] The processor may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of this disclosure, the processor is used to execute computer-readable instructions stored in the memory.
[0185] Those skilled in the art will understand that, in order to solve the technical problem of how to achieve a good user experience, this embodiment may also include well-known structures such as communication buses and interfaces, and these well-known structures should also be included within the protection scope of this disclosure.
[0186] For a detailed description of this embodiment, please refer to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.
[0187] Example 5
[0188] This disclosure provides a non-transitory computer-readable storage medium that stores computer instructions for causing a computer to execute the well microseismic event localization method of Embodiment 1.
[0189] A computer-readable storage medium according to embodiments of the present disclosure stores non-transitory computer-readable instructions. When these non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the methods described in the foregoing embodiments of the present disclosure are performed.
[0190] The aforementioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or portable hard drive), media with built-in rewritable non-volatile memory (e.g., memory card), and media with built-in ROM (e.g., ROM cartridge).
[0191] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.
Claims
1. A method for locating microseismic events in a well, characterized in that, include: Based on the three-component microseismic monitoring data of the three wells, horizontal polarization analysis and vertical polarization analysis were carried out successively to obtain the horizontal azimuth and vertical azimuth of the P-wave propagation direction of each well. The horizontal plane location coordinates of microseismic events are calculated based on the horizontal azimuth angle and the horizontal plane coordinates of the geophone for each well. The vertical depth coordinates of the microseismic event are calculated based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth of each well. The well-hole microseismic event location is completed based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic event.
2. The well microseismic event localization method according to claim 1, characterized in that, The process of obtaining the horizontal azimuth angle of the P-wave propagation direction for each well includes: Establish a mutually perpendicular coordinate system YX for each well, with the X component direction as the horizontal axis and the Y component direction as the vertical axis. Plot the connection diagram of the microseismic event signal data of the X component and Y component in chronological order. Obtain the first azimuth linear equation by fitting the linear characteristics. The horizontal azimuth angle of the P-wave propagation direction in the YX plane of the coordinate system is calculated based on the first azimuth linear equation.
3. The well microseismic event localization method according to claim 2, characterized in that, The process of obtaining the vertical azimuth angle of the P-wave propagation direction for each well includes: Based on the horizontal azimuth angle of each well, the microseismic event signal data of their respective X and Y components are rotated to obtain the R component along the P-wave propagation direction and the T component perpendicular to the P-wave propagation direction of each well. Establish a mutually perpendicular coordinate system RZ for the R component and vertical component Z of each well. With the direction of the Z component as the horizontal axis and the direction of the R component as the vertical axis, draw a line diagram connecting the microseismic event signal data of the R component and Z component in chronological order. Obtain the second azimuth linear equation by fitting the linear characteristics. The vertical azimuth angle of the P-wave propagation direction in the RZ plane of the coordinate system is calculated based on the second azimuth linear equation.
4. The well microseismic event localization method according to claim 1, characterized in that, The calculation of the horizontal plane location coordinates of microseismic events based on the horizontal azimuth angle and the horizontal plane coordinates of the geophone for each well includes: Construct three straight lines in the horizontal plane of the YX coordinate system to indicate the direction of P-wave propagation. Obtain the detector horizontal plane coordinates of each straight line passing through the corresponding detector on the YX horizontal plane of the coordinate system; The coordinates of the intersection points of the three straight lines are calculated based on the horizontal azimuth angle of each well and the corresponding horizontal plane coordinates of the detector. The average of the x and y coordinates of the three intersection points is the horizontal plane location coordinate of the microseismic event.
5. The well microseismic event localization method according to claim 4, characterized in that, The calculation of the vertical depth positioning coordinates of the microseismic event based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth angle of each well includes: Based on the vertical azimuth angle of each well, the horizontal plane coordinates of the geophone, and the formation velocity, the transmission angle of each formation between the geophone location in each well and the formation of the microseismic event is calculated using Snell's law. Wherein, the vertical azimuth angle of each well is the transmission angle of the formation where the corresponding geophone is located; The length of the horizontal segment of the first transducer P-wave propagation ray path from the stratum where the corresponding geophone is located to the stratum above the stratum of the microseismic event is calculated based on the transmission angle of each well. Calculate the total horizontal distance from the location of the microseismic event to the detector based on the horizontal plane positioning coordinates of the microseismic event; The length of the second P-wave propagation path of the geophone is calculated based on the total horizontal distance and the length of the horizontal segment of the first geophone P-wave propagation ray path. The thickness of the stratum where the microseismic event is located in each well is calculated based on the transmission angle of the stratum where the microseismic event is located and the length of the horizontal segment of the P-wave propagation path through the second detector. The vertical depth coordinates of the microseismic event in each well are calculated based on the geophone depth coordinates of each well and the thickness of each stratum from the geophone location to the seismic event location. The average value of the vertical depth coordinates of the microseismic events in the three wells is used to determine the vertical depth coordinates of the microseismic events.
6. The well microseismic event localization method according to claim 2, characterized in that, The first azimuth linear equation is: y i,j =tgα i *x i,j +b i 4 Where, α i The angle between the direction of P-wave propagation in the i-th well and the X component in the YX plane of the coordinate system represents the horizontal azimuth angle of the direction of P-wave propagation in the i-th well in the YX plane of the coordinate system. i,j For X component monitoring data, y i,j For Y component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, b i Let be the intercept of the linear equation for the first azimuth angle of the i-th well.
7. The well microseismic event localization method according to claim 1, characterized in that, The second azimuth linear equation is: R i,j =tgβ i *z i,j +c i ; Where, β i The angle between the propagation direction of the P-wave in the i-th well and the X component on the RZ plane of the coordinate system is the horizontal azimuth angle of the propagation direction of the P-wave in the i-th well on the RZ plane of the coordinate system. i,j For Z component monitoring data, R i,j For R-component monitoring data, i = 1, 2, 3, representing the serial numbers of the three wells, j = 1, 2, ..., N, where N is the total number of sampling points, c i Let be the intercept of the linear equation for the second azimuth angle of the i-th well.
8. An electronic device, characterized in that, The electronic device includes: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the well microseismic event localization method according to any one of claims 1-7.
9. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to perform the well microseismic event localization method according to any one of claims 1-7.
10. A well-drilled microseismic event location device, characterized in that, include: The polarization analysis module is used to perform horizontal polarization analysis and vertical polarization analysis based on the three components of microseismic monitoring data from each of the three wells, and to obtain the horizontal and vertical azimuth angles of the P-wave propagation direction of each well. The first calculation module is used to calculate the horizontal plane positioning coordinates of microseismic events based on the horizontal azimuth angle of each well and the horizontal plane coordinates of the geophone. The second calculation module is used to calculate the vertical depth positioning coordinates of the microseismic event based on the horizontal plane positioning coordinates of the microseismic event and the vertical azimuth angle of each well. The positioning module is used to locate microseismic events in the well based on the horizontal plane positioning coordinates and the vertical depth positioning coordinates of the microseismic events.