Method and equipment for three-dimensional seismic space homing of horizontal well geosteering picture

Abstract

The invention discloses a horizontal well geosteering picture three-dimensional seismic space homing method and device, and belongs to the field of physical exploration. According to the method, data are collected, the well trajectory information base is established, digital information in the geosteering picture is obtained after the engineering drawing is digitized, and the space coordinates of the geosteering picture are obtained through the well trajectory information base; and carrying out three-dimensional seismic space homing on the geosteering picture of the target stratum and the like to finally obtain a three-dimensional seismic data volume after geosteering picture space homing. According to the invention, the well trajectory is used as a bridge, and a two-dimensional geosteering result and a three-dimensional earthquake are visually associated, so that a real stratum reflected by a geosteering picture is visually reflected in a three-dimensional earthquake data body; the objective of objectively evaluating the three-dimensional seismic data volume from the same observation angle and effectively predicting the depth, the inclination angle, the breakpoint position and the micro-amplitude structure is achieved. The method is applied to shale gas horizontal well drilling and further applied to interpretation and analysis of geological structures.

Description

Technical Field

[0001] The invention belongs to the field of physical exploration and relates to a geophysical signal interpretation, specifically a method and equipment for three-dimensional seismic space repositioning of horizontal well geological steering pictures. Background Art

[0002] Geosteering technology is one of the core technologies for drilling shale gas horizontal wells, but the conventional geosteering method based on a single measurement while drilling parameter can no longer meet the large-scale commercial development of shale gas. Due to the thin target thickness of the horizontal well drilling target of shale gas in southern Sichuan Basin, the platinum target thickness in some areas is less than 10 meters, and the micro-structure is well developed, the drilling difficulty is very high. In order to promote the refined development and iteration of geophysical technology, under the integrated idea of ​​seismic-geology-engineering, multidisciplinary collaboration is needed to effectively analyze and evaluate the existing technical achievements, so as to seek technical breakthroughs and improve the supporting effect of geophysical exploration technology in drilling projects.

[0003] Since drilling guidance and earthquake prediction are two independent disciplines, drilling guidance is to present a three-dimensional continuous geological body in the form of a two-dimensional profile, and its completed geological guidance result profile has depth and horizontal displacement information; while the depth domain three-dimensional seismic is a three-dimensional space discrete data body with information such as X, Y coordinates and depth. According to the current three-dimensional seismic observation system, the three-dimensional seismic data has a surface element feature (for example, 20m*20m) and is a discrete data body. At present, the working method of combining drilling guidance with earthquake prediction is mainly to intercept the two-dimensional seismic profile along the well trajectory in the three-dimensional seismic data body, and calibrate the position with the two-dimensional drilling guidance picture by designing the target entry point (point A), designing the target exit point (point B) or actually drilling the target entry point (point A) and the target exit point (point B). The two are compared with the naked eye to analyze and evaluate the earthquake prediction effect. The result is a qualitative description, and the accuracy and reliability need to be improved. That is, in the existing technology, the two-dimensional picture obtained by the three-dimensional seismic data body is mainly superimposed with the two-dimensional photo of the geological guidance picture, and the real stratum reflected by the geological guidance picture cannot be reflected in the three-dimensional seismic data body.

[0004] Due to the different observation angles and methods of drilling guidance and seismic prediction, there are disciplinary barriers when the two are crossed. It is difficult to directly put the geosteering images obtained by drilling guidance and the three-dimensional seismic volume obtained by seismic prediction on the same platform for comparative analysis. The specific reasons are: (1) The three-dimensional seismic volume is a discrete data volume in three-dimensional space, with information such as X, Y coordinates and depth; while the geosteering image only contains the elevation depth and horizontal displacement information obtained based on the well trajectory algorithm, and does not have the X, Y information in the three-dimensional seismic volume. (2) The completed geosteering image is a three-dimensional continuous geological body presented in the form of a two-dimensional profile, with horizontal displacement and elevation depth information; while the three-dimensional seismic data has the characteristics of surface elements and is a discrete data volume, and the discreteness of the geosteering image and the three-dimensional data volume is often mismatched. Therefore, if the real strata reflected by the completed geosteering image are to be reflected in the three-dimensional seismic volume, the above two problems need to be overcome. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for intuitively linking the two-dimensional geological guidance results with the three-dimensional seismic data body, realizing the embodiment of the real strata reflected in the geological guidance image in the three-dimensional seismic body, and objectively evaluating the accuracy of the current three-dimensional seismic data body in terms of depth, dip, breakpoint position and micro-structure prediction from the same observation angle.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A method for three-dimensional seismic spatial positioning of horizontal well geosteering images, the method comprising the following steps performed in sequence: S1. Collecting information Collect data to obtain 3D seismic data of the target formation in depth, horizontal well drilling data, and geosteering images of completed horizontal wells; S2. Establishing a well trajectory information database Based on the horizontal well drilling data, after obtaining the X, Y coordinate information and horizontal displacement through the minimum curvature method, the well trajectory is interpolated to establish a well trajectory information database; S3. Digital engineering drawings, obtaining digital information from geo-steering images Define the coordinate system of the drilling guidance picture, pick up the geological guidance picture of the completed horizontal well after digitizing the engineering drawing, and output the altitude depth and horizontal displacement data of the target formation in the coordinate system according to the specific sampling interval; S4. Use the well trajectory information database to obtain the spatial coordinates of the geosteering image Using the horizontal displacement data of the target formation as a bridge, searching the X coordinate and Y coordinate corresponding to the same horizontal displacement in the well trajectory information library, adding the altitude depth information corresponding to the same horizontal displacement in step S3, and combining them into spatial coordinates; S5. 3D seismic spatial positioning of target stratum geosteering images The X and Y coordinate information in the spatial coordinates are projected to the seismic network for matching using the minimum distance method; The altitude depth information in the spatial coordinates is input into the depth domain three-dimensional seismic data volume, the three-dimensional seismic spatial positioning of the geosteering image of the target stratum is completed, and a three-dimensional seismic multi-information data volume including the depth of the target stratum is obtained.

[0007] Preferably, in step S1, the horizontal well drilling data includes wellhead coordinates, core patching elevation and well trajectory data.

[0008] Preferably, in step S2, the horizontal well drilling data includes data such as deflection depth, well inclination angle, well inclination azimuth, X coordinate, Y coordinate and horizontal displacement.

[0009] Preferably, in step S3, in the drilling guide image coordinate system, the abscissa is the horizontal displacement and the ordinate is the altitude depth; The interval distance of the specific sampling interval matches the size of the seismic bin in the three-dimensional seismic data volume in the depth domain.

[0010] Preferably, in step S5, The projection on the seismic network based on the minimum distance method includes matching the obtained X and Y coordinates with the seismic network coordinates, searching for the Inline and Crossline positions of the seismic network that are closest to the coordinates, and converting the coordinate positions into network positions.

[0011] Preferably, after step S5, step S6 may be further included to perform three-dimensional seismic positioning of the true elevations of each small layer in the adjacent strata of the target stratum, specifically including: S61. Using the horizontal well geological guidance map, obtain the thickness difference between the bottom boundary of the internal sublayer in the formation adjacent to the target formation and the bottom boundary of the target formation; S62. Based on the altitude depth information in the three-dimensional seismic multi-information data volume containing the depth of the target stratum obtained in step S5, the altitude depth of each sublayer in the stratum adjacent to the target stratum is calculated using the thickness difference obtained in step S61, and then displayed in the three-dimensional seismic data volume to obtain the three-dimensional seismic spatial position of each sublayer in the stratum adjacent to the target stratum.

[0012] The present invention also provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for three-dimensional seismic spatial positioning of horizontal well geological guidance images is implemented.

[0013] The present invention also provides a computer-readable storage medium, which stores a computer program for executing the above-mentioned method for three-dimensional seismic spatial positioning of horizontal well geological steering images.

[0014] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art: ① The present invention provides a method for spatial homing of horizontal well geosteering images in three-dimensional seismic space. The method uses the well trajectory as a bridge to intuitively link the two-dimensional geosteering results with three-dimensional seismic, and achieves the purpose of objectively evaluating the current three-dimensional seismic data body for effective prediction of depth, dip, breakpoint position and micro-structure from the same observation angle. Based on this, the seismic depth data obtained by different offset processing methods can also be evaluated, which is conducive to the iteration of high-precision geophysical exploration technology; ② Different from the conventional geosteering image which combines a 2D section with a 2D image when combining the 3D seismic data volume, the present invention proposes for the first time to give the geosteering image X and Y spatial information, and upgrade the geosteering image from 2D to 3D. By combining 3D with 3D, the actual drilled geological layer is truly returned to the seismic data space, which is conducive to further interpretation and analysis of geological structure; ③ Step S2 in the present invention is a more critical step in this method. This step is based on the well inclination data such as the collected inclination depth, well inclination angle, well inclination azimuth, etc., and uses the minimum curvature method to calculate the X and Y coordinates, and then combines the horizontal displacement, closing azimuth and other information to interpolate the well trajectory and establish a well trajectory information library. The purpose of this step is to provide a method for obtaining X and Y coordinate information in the well trajectory data; second, to interpolate the discrete points in the well trajectory into a continuous and smooth curve, which is conducive to the subsequent acquisition of X and Y coordinate information in the geological guidance picture that matches the discreteness of the three-dimensional seismic data body and lays the foundation; the purpose of steps S3~S4 is to assign spatial coordinates to the target stratum in the geological guidance map, obtain the horizontal displacement and altitude depth of the target stratum through the digitized engineering drawing, and use the horizontal displacement to search for the corresponding X and Y coordinates in the well trajectory information library of step S2, so that the target stratum in the geological guidance map obtains X, Y coordinates and altitude depth information, which is the core step in this method; ④ In step S5 of the present invention, the spatial coordinate information is projected onto the three-dimensional seismic network, and the spatial coordinates of X, Y, and altitude depth obtained in step S4 are converted into the Inline and Crossline positions of the seismic network by the minimum distance principle, and the Inline, Crossline, and altitude depth data are input into the three-dimensional seismic; ⑤ The three-dimensional seismic data volume obtained by the present invention after the spatial relocation of the geosteering image of the target stratum can further realize the three-dimensional seismic relocation of the real altitude of each internal small layer in the adjacent stratum of the target stratum according to the thickness difference between the bottom boundary of the internal small layer in the adjacent stratum of the target stratum and the bottom boundary of the target stratum, laying a foundation for the interpretation and analysis of the overall geological structure; ⑥ The present invention also provides electronic equipment and storage media for executing the method for three-dimensional seismic spatial repositioning of horizontal well geological steering images, with complete software and hardware supporting facilities, which facilitates the promotion and use of the test method.

[0015] The present invention is applied to shale gas horizontal well drilling, especially to exploration areas with thin target body thickness or micro-structure development and high drilling difficulty, and is further applied to the interpretation and analysis of geological structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] Figure 1 This is a flow chart of the method for three-dimensional seismic spatial positioning of horizontal well geosteering images in Example 1 of the present invention; Figure 2 This is a three-dimensional seismic spatial homing effect diagram of the geosteering image of the Lu 203HX-A well in Example 1 of the present invention; Figure 3 This is a comparison chart of the prediction effects of seismic depth data obtained by different processing methods for the bottom boundary of the Wufeng Formation in Well Lu 203HX-A in Example 1 of the present invention. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below by means of specific embodiments in combination with the accompanying drawings. It should be understood that the described embodiments are preferred examples of the present invention and are only used to explain the present invention and do not limit the present invention.

[0019] Example 1 A method for 3D seismic spatial positioning of horizontal well geosteering images At present, the target thickness of the horizontal well drilling target of shale gas in southern Sichuan is thin, the platinum target thickness in some areas is less than 10 meters, and the micro-structure is well developed, so the drilling difficulty is very high. This embodiment takes the bottom boundary stratum of the Wufeng Formation in the southern Sichuan area of ​​the Sichuan Basin as an example to provide a method for 3D seismic spatial positioning of horizontal well geosteering images. The flow chart is as follows: Figure 1 As shown, the method includes the following steps performed in sequence: S1. Collecting information Collect data to obtain 3D seismic data in the depth domain related to the bottom boundary of the Wufeng Formation, horizontal well drilling data, and geosteering images of completed horizontal wells; The horizontal well drilling data includes wellhead coordinates, core filling elevation and well trajectory data; S2. Establishing a well trajectory information database Based on the parameters such as the inclination depth, well inclination angle, well inclination azimuth in the well trajectory data, the X, Y coordinates and horizontal displacement at a certain inclination depth are calculated by the minimum curvature method, and then the well trajectory is interpolated in combination with the closed azimuth to establish a well trajectory information database; S3. Digital engineering drawings, obtaining digital information from geo-steering images S31. Define a drilling steering image coordinate system, wherein the coordinate system uses horizontal displacement as the abscissa and elevation depth as the ordinate to digitize the geological steering image; S32. Manually pick the bottom boundary stratigraphic interface of the Wufeng Formation on the digital geosteering image, and output digital information including altitude depth and horizontal displacement data at a sampling interval of 20 meters in the above coordinate system; The reason for choosing 20 meters as the sampling interval is that in the seismic observation system of the three-dimensional seismic data volume in the depth domain, the bin size is 20 meters; S4. Use the well trajectory information database to obtain spatial coordinates Using the horizontal displacement data of the bottom boundary of the Wufeng Formation obtained in step S32 as a bridge, search for the X-coordinate and Y-coordinate information corresponding to the same horizontal displacement in the well trajectory information library obtained in step S2, add the altitude depth information corresponding to the same horizontal displacement in step S3, and combine them into spatial coordinates; S5. 3D seismic spatial positioning of target stratum geosteering images The spatial coordinates are projected onto the seismic network using the minimum distance method for matching, the obtained X and Y coordinates are matched with the seismic network coordinates, the Inline and Crossline positions of the seismic network closest to the coordinates are searched, and the coordinate positions are converted into network positions; The altitude depth information in the spatial coordinates is further input into the three-dimensional seismic data volume in the depth domain to complete the three-dimensional seismic spatial positioning of the geological guidance image of the bottom boundary stratum of the Wufeng Formation, and obtain a three-dimensional seismic multi-information data volume containing the depth information of the bottom boundary stratum of the Wufeng Formation.

[0020] Project the X and Y coordinate information in the spatial coordinates obtained in step S4 onto the seismic network for matching based on the minimum distance method, match the obtained X and Y coordinates with the seismic network coordinates, search for the Inline and Crossline positions of the seismic network closest to the coordinates, and convert the coordinate positions into the network positions; According to the location of the survey network, the altitude depth information in the spatial coordinates is further input into the three-dimensional seismic data body to complete the three-dimensional seismic spatial repositioning of the geological guidance picture of the bottom boundary of the Wufeng Formation, and obtain the three-dimensional seismic data body after the spatial repositioning of the geological guidance picture of the bottom boundary of the Wufeng Formation.

[0021] S6. 3D seismic location of the true elevation of the internal sub-layers in the adjacent layers of the target layer S61. Using the horizontal well geological guidance map, obtain the thickness difference between the bottom boundary of each small layer in the Longmaxi Formation Long-11, which is adjacent to the bottom boundary of the Wufeng Formation and above it, and the bottom boundary of the Wufeng Formation; S62. Based on the altitude depth of the three-dimensional seismic multi-information data body containing the bottom boundary stratigraphic depth information of the Wufeng Formation obtained in step S5, the thickness difference obtained in step S61 is used to calculate the altitude depth of each small layer inside Longmaxi Formation Longyi 1 and then display it in the three-dimensional seismic data body to obtain the three-dimensional seismic spatial relocation of each small layer inside Longyi 1 of the target Longmaxi Formation. Among them, the three-dimensional seismic spatial relocation effect diagram of the geosteering image of Lu 203HX-A well is as follows Figure 2 shown.

[0022] Depend on Figure 2 It can be seen that the geosteering image is directly displayed in the 3D seismic data. The actual positions of the Wufeng Formation, sublayer 1, sublayer 2, sublayer 3, and sublayer 4 in the image are intuitively and accurately presented on the seismic phase axis. It can also be seen from the figure that the seismic prediction accuracy of the depth of the horizontal well into the target point is high, the seismic predicted stratum strike in the first half is more consistent with the actual stratum strike than in the second half, the micro-tectonic seismic response in the middle is relatively weak, and the tail seismic depiction of the fault position is accurate. This figure can intuitively link the results of 2D geosteering with 3D seismic, and objectively evaluate the accuracy of the current 3D seismic prediction of depth, dip, breakpoint position, and micro-tectonic prediction from the same observation angle.

[0023] Based on the three-dimensional seismic spatial repositioning of the geosteering image of the Lu 203HX-A well obtained by the present invention, it can be further applied to evaluate the seismic depth data obtained by different offset processing methods. For example, the predicted depth data obtained by different processing methods such as time-depth conversion, VTI anisotropic offset, and TTI anisotropic offset are compared with the actual formation, so as to more intuitively select the offset processing method suitable for the local formation. Figure 3 This is a comparison chart of the prediction effects of seismic depth data obtained by different processing methods for the bottom boundary strata of the Wufeng Formation in Well Lu 203HX-A.

[0024] The method for 3D seismic spatial positioning of horizontal well geosteering images provided by the present invention has been well applied in 3D seismic tracking of shale gas in the Sichuan Basin. At present, 3D seismic spatial positioning of geosteering images of more than 150 shale gas horizontal wells in the southern Sichuan shale gas block has been completed, and good application results have been achieved.

[0025] Embodiment 2 A computer device This embodiment provides a computer device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, so as to implement the above-mentioned method for three-dimensional seismic spatial positioning of horizontal well geosteering images.

[0026] The above-mentioned memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, a random access memory (RAM) and / or a cache memory (cache), etc. The non-volatile memory may include, for example, a read-only memory (ROM), a hard disk, a flash memory, etc.

[0027] The processor may be a central processing unit (CPU) or other processing units having data processing capability and / or instruction execution capability, and may control other components in the electronic device to perform desired functions. The processor is used to execute the computer-readable instructions stored in the memory.

[0028] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.

[0029] Embodiment 3 A computer readable storage medium This embodiment provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the method for three-dimensional seismic spatial positioning of horizontal well geosteering images is implemented.

[0030] The computer-readable storage medium stores non-transitory computer-readable instructions. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of various embodiments are executed.

[0031] The above-mentioned 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 mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0032] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for three-dimensional seismic spatial positioning of horizontal well geosteering images, characterized in that: The method comprises the following steps performed in sequence: S1. Collecting information Collect data to obtain 3D seismic data of the target formation in depth, horizontal well drilling data, and geosteering images of completed horizontal wells; S2. Establishing a well trajectory information database Based on the horizontal well drilling data, after obtaining the X, Y coordinate information and horizontal displacement through the minimum curvature method, the well trajectory is interpolated to establish a well trajectory information database; S3. Digital engineering drawings, obtaining digital information from geo-steering images Define the coordinate system of the drilling guidance image, digitize the engineering drawing, pick up the geological guidance image of the completed horizontal well, and output the altitude depth and horizontal displacement data of the target formation at a specific sampling interval; S4. Use the well trajectory information database to obtain the spatial coordinates of the geosteering image Using the horizontal displacement data of the target formation as a bridge, searching the X coordinate and Y coordinate corresponding to the same horizontal displacement in the well trajectory information library, adding the altitude depth information corresponding to the same horizontal displacement in step S3, and combining them into spatial coordinates; S5. 3D seismic spatial positioning of target stratum geosteering images The X and Y coordinate information in the spatial coordinates are projected to the seismic network for matching using the minimum distance method; The altitude depth information in the spatial coordinates is input into the depth domain three-dimensional seismic data volume, the three-dimensional seismic spatial positioning of the geosteering image of the target stratum is completed, and a three-dimensional seismic multi-information data volume including the depth of the target stratum is obtained.

2. The method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to claim 1 is characterized in that: In step S1, the horizontal well drilling data includes wellhead coordinates, core elevation and well trajectory data.

3. The method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to claim 1 is characterized in that: In step S2, the horizontal well drilling data includes data including deflection depth, well inclination angle, well inclination azimuth, X coordinate, Y coordinate and horizontal displacement.

4. The method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to claim 1, characterized in that: In step S3, in the drilling guidance image coordinate system, the abscissa is the horizontal displacement and the ordinate is the altitude depth; The interval distance in the specific sampling interval matches the size of the seismic bin in the three-dimensional seismic data volume in the depth domain.

5. The method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to any one of claims 1 to 4, characterized in that: In step S5, The projection on the seismic network based on the minimum distance method includes matching the obtained X coordinates and Y coordinates with the seismic network coordinates, searching for the inline and crossline positions of the seismic network with suitable distances from the coordinates, and converting the coordinate positions into network positions.

6. The method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to claim 5, characterized in that: The step S5 also includes step S6 of three-dimensional seismic positioning of the true elevation of each small layer in the adjacent strata of the target stratum, which specifically includes: S61. Using the horizontal well geological guidance map, obtain the thickness difference between the bottom boundary of the internal sublayer in the formation adjacent to the target formation and the bottom boundary of the target formation; S62. Based on the three-dimensional seismic multi-information data volume containing the depth of the target stratum, the altitude depth of each sub-layer in the stratum adjacent to the target stratum is calculated using the thickness difference and then displayed in the three-dimensional seismic data volume to obtain the three-dimensional seismic spatial position of each sub-layer in the stratum adjacent to the target stratum.

7. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program for executing the method for three-dimensional seismic spatial positioning of horizontal well geosteering images according to any one of claims 1 to 6.

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