Method and device for correcting VSP data, electronic equipment and storage medium
The VSP logging speed is corrected by acoustic well logging data, and the problem of insufficient accuracy of zero-bias VSP on thin-layer high-speed layers is solved, improving the accuracy of logging speed and the processing accuracy of seismic data.
Patent Information
- Application Number
- CN202410138416.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-31
- Publication Date
- 2025-08-01
AI Technical Summary
The existing zero-bias VSP logging is insufficient in the thin-layer high-speed layer, which cannot accurately reflect the lateral changes of the formation, and the measurement depth error is large.
Through the acoustic logging data, the thickness and stratigraphic boundary points of the thin layer high-speed layer are counted, the median difference between VSP logging velocity and acoustic logging velocity is calculated, and the VSP logging velocity is corrected using a primary function fitting, and depth correction is performed.
The accuracy of VSP logging speed is improved, the data processing accuracy of ground seismic velocity is enhanced, and the accuracy of underground structure interpretation is ensured.
Smart Images
Figure CN120405769A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of oil and gas exploration, and particularly relates to a method, device, electronic device and storage medium for correcting VSP data. Background Technique
[0002] Acoustic logging is a geophysical logging method used to measure the velocity and attenuation of acoustic waves during propagation in underground rocks, thereby inferring the physical properties and lithology of the rocks. Acoustic logging mainly obtains the acoustic velocity information of underground rocks by placing a sound source and receivers in the well, sending acoustic signals underground and receiving the reflected and propagated acoustic signals. In acoustic logging, the acoustic signals are usually sent in the form of acoustic pulses, which can be single-frequency or multi-frequency signals with a very wide bandwidth. When the acoustic signals propagate through underground rocks, they are affected by the elastic and attenuation characteristics of the rocks, such as velocity, density, porosity, saturation, etc. By measuring the changes in the propagation time and energy intensity of the acoustic signals, the acoustic velocity and attenuation characteristics of underground rocks can be calculated, thereby inferring the physical properties of the rocks. Acoustic logging is widely used in the fields of oil and gas exploration and geological engineering, and can be used to determine information such as the porosity, saturation, compaction degree, and fracture characteristics of rocks, which is of great significance for studying the composition, structure, and reservoir characteristics of strata.
[0003] Acoustic logging has the characteristics of high measurement accuracy, good resolution, and can provide relatively accurate physical property parameters. It has a very high resolution especially for thin layers, but the detection range of acoustic logging is small, and it can only measure the acoustic characteristics of the rocks in the well and cannot provide information on the lateral changes of the strata. Zero-offset VSP can provide information on the lateral changes of the strata. VSP (Vertical Seismic Profile) is a seismic exploration method used to detect the properties and structures of underground layers. Its principle is to arrange a series of seismic detectors in the vertical direction near the seismic center point, and then record the seismic data and analyze and invert parameters such as the velocity and density of the underground layers. Zero-offset VSP refers to a way of arranging the seismic detectors by placing the detectors on the ground. Compared with other VSP methods, the characteristic of zero-offset VSP is that the first detector in the detector is placed on the ground, and its position coincides with the seismic center point. The remaining detectors are arranged underground at a certain interval. Such an arrangement can effectively reduce or eliminate the noise interference caused by the ground interface, improve the quality of the data, and make the study of underground layers more accurate.
[0004] Both acoustic logging and zero-offset VSP (Vertical Seismic Profile) infer the physical properties and lithology of subsurface rocks by measuring the propagation characteristics of acoustic waves in subsurface rocks. Acoustic logging is carried out in the well, while zero-offset VSP is measured by setting detectors near the ground. The advantage of zero-offset VSP is that it can provide information on lateral changes in the formation, is suitable for studying complex subsurface structures, and has a large measurement range. By arranging detectors near the ground and conducting seismic recordings, and analyzing the propagation characteristics of seismic waves, it directly improves the measurement accuracy of surface seismic velocity. However, zero-offset VSP logging has insufficient accuracy in reflecting thin high-velocity layers, and the measurement depth error is larger than that of conventional acoustic logging.
[0005] Therefore, there is an urgent need to provide a method for correcting VSP data to solve the technical problem of insufficient accuracy of VSP logging in thin high-velocity layers. Summary of the Invention
[0006] To solve the above technical problems existing in the prior art, the present invention provides a method, device, electronic device, and storage medium for correcting VSP data, aiming to correct the surface seismic velocity of VSP data through conventional acoustic logging and improve the accuracy of the surface seismic velocity in VSP data.
[0007] To achieve the above object, the technical solution of the present invention is as follows:
[0008] A method for correcting VSP data includes:
[0009] S1. Based on acoustic logging data, count the thickness of thin high-velocity layers in the target area and mark the formation boundary points in the target area;
[0010] S2. Calculate the median values of VSP logging velocity and acoustic logging velocity for different formations respectively. By comparing the median values of VSP logging velocity and acoustic logging velocity, determine the formations with a large median difference (greater than or equal to 3) for comparative analysis;
[0011] S3. Based on the median comparison analysis result in step S2, correct the VSP logging velocity, and then reprocess the VSP data to correct the depth of the VSP data.
[0012] Furthermore, before counting the thickness of thin high-velocity layers in the target area in step S1, it is necessary to determine the accuracy of the acoustic logging data.
[0013] Even further, the accuracy of the acoustic logging data is determined by using the monopole longitudinal wave method and / or the waveform pattern search method.
[0014] Even further, use the monopole longitudinal wave method to determine the position of the formation interface; use the waveform pattern search method to determine the boundary between different formations.
[0015] Further, the VSP logging velocity includes the pressure wave velocity, shear wave velocity, acoustic wave velocity, temperature, and pressure change velocity.
[0016] Further, the set threshold in step S2 is 3.
[0017] Further, the specific method for correcting the VSP logging velocity in step S3 includes: establishing a linear function using the sonic logging velocity value, and fitting the VSP logging velocity data to the linear function for correction.
[0018] Further, the specific method for correcting the depth of the VSP data in step S3 includes: performing overall translation, stretching, or compression on the VSP data.
[0019] The present invention also provides a device for correcting VSP data, adopting the above method for correcting VSP data, including:
[0020] A data acquisition module, configured to acquire sonic logging data and VSP logging data of a target area;
[0021] An analysis module, configured to analyze the sonic logging data and VSP logging data, determine the difference points and similarity points, and analyze the difference in the median;
[0022] A calculation module, configured to calculate the median of the VSP logging data and sonic logging data of different formations, and transfer the data to the analysis module;
[0023] A correction module, configured to correct the velocity and depth of the VSP data.
[0024] The present invention also provides an electronic device, including a memory and a processor, where the memory stores executable instructions; the processor runs the executable instructions in the memory to implement the above method for correcting VSP data.
[0025] The present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the above method for correcting VSP data is implemented.
[0026] Compared with the prior art, the present invention has the following beneficial effects:
[0027] The method for correcting VSP data provided by the present invention is based on sonic logging data, analyzes the differences between the sonic logging data and VSP logging data, and determines the formations where the medians of the sonic logging data and VSP logging data differ significantly through median calculation. Then, the VSP logging velocity is corrected, and afterwards, the VSP depth is corrected, improving the accuracy of the logging velocity in VSP logging and the accuracy of ground seismic data processing speed. Brief Description of the Drawings
[0028] Figure 1 This is a flowchart of the method of the present invention.
[0029] Figure 2 This is a framework diagram of the device of the present invention. Detailed Embodiments
[0030] The technical solutions of the present invention will be clearly described below in conjunction with the description of the drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0031] It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps described in these embodiments and numerical expressions should not be construed as limiting the scope of the present invention.
[0032] The following description of the exemplary embodiments is merely illustrative and in no way limits the present invention and its application or use. Technologies, methods, and devices known to those of ordinary skill in the relevant fields may not be discussed in detail here, but when applicable, these technologies, methods, and devices should be regarded as part of this specification.
[0033] Embodiment 1
[0034] The present invention provides a method for correcting VSP data. As Figure 1 shown in the flowchart of the method, it includes:
[0035] S1. Based on the acoustic logging data, determine the accuracy of the acoustic logging data by the monopole longitudinal wave method and the waveform pattern search method, then statistically analyze the thickness of the thin high-velocity layers in the target area, and mark the formation boundary points in the target area;
[0036] Specifically, it can be to determine the position of the formation interface by analyzing the acoustic velocity information in the conventional acoustic logging data and applying the monopole longitudinal wave method. At the same time, use the waveform pattern search method to identify unique waveform patterns, that is, specific seismic waveform patterns, to determine the boundaries between different formations. Through these analyses, the thickness of the thin high-velocity layers in this area can be statistically analyzed, the formation interface can be accurately located, and then the formation boundary points can be marked.
[0037] Among them, the monopole longitudinal wave method uses a monopole sound source in the well to radiate longitudinal waves outside the well and receives the longitudinal waves reflected from geological bodies outside the well to determine the location of the geological bodies. The waveform template matching method is a seismic detection method. It is based on a simple assumption that each seismic event has a unique seismic waveform pattern, similar to a fingerprint. This method determines the occurrence of a seismic event by collecting and establishing a database of seismic waveforms of a series of seismic events in advance and then comparing the monitored seismic waveforms with the waveforms in the database to find the matching waveform pattern. The advantage of this method is that it can provide high accuracy and reliability, but it requires a large amount of waveform data and a long calculation time.
[0038] S2. Calculate the median values of the VSP logging velocity and the acoustic logging velocity for different formations respectively. By comparing the median values of the VSP logging velocity and the acoustic logging velocity, determine the formations with a large difference in median values for comparative analysis. In this embodiment, the determination threshold for the median value is set to 3. If the median value is greater than or equal to 3, it is considered a large difference and correction is required.
[0039] Among them, the VSP logging velocity includes:
[0040] The pressure wave velocity, which is the velocity of the pressure wave propagating in the underground reservoir. The pressure wave velocity is the most commonly used velocity parameter in VSP logging. It can provide information such as formation density, rock elasticity, porosity, and fluid saturation.
[0041] The shear wave velocity, which is the velocity of the shear wave propagating in the underground reservoir. The shear wave velocity can provide information such as the shear strength in the formation, the shear modulus of the rock, and the porosity of the rock.
[0042] The acoustic wave velocity, which is the velocity of the acoustic wave propagating in the underground reservoir. The acoustic wave velocity can provide information such as the pressure intensity, fluid saturation, and porosity in the formation.
[0043] The temperature and pressure change velocity, which is the velocity of the temperature and pressure changes in the underground reservoir. They can provide information about the formation permeability and fluid migration.
[0044] All in all, the VSP logging velocity can provide information such as formation density, elasticity, rock type, rock shear characteristics, porosity, fluid saturation, and permeability. These information are of great significance for reservoir evaluation and oil reservoir development in petroleum exploration.
[0045] In the process of analyzing and calculating the median values of VSP logging velocities and acoustic logging velocities in different strata, it is also possible to assist in statistically analyzing the differences and similarities between VSP logging velocities and acoustic logging velocities. The specific methods include: marking VSP logging velocities by stratigraphic horizon, comparing VSP logging velocities with acoustic logging velocities, and statistically analyzing the differences and similarities between VSP logging velocities and acoustic logging velocities. Both the differences and similarities are formation velocities, one obtained by VSP measurement and the other by acoustic logging measurement. The judgment criterion is the velocity difference between the two. If the difference > 100 m / s, it is a difference point; otherwise, it is a similarity point. The purpose of analyzing and statistically analyzing the differences and similarities is to assist in judging the strata that need to be corrected.
[0046] S3. Based on the median comparison and analysis results in step S2, correct the VSP logging velocity, and then reprocess the VSP data to correct the depth of the VSP data.
[0047] Among them, the thin high-velocity layer refers to a relatively thin stratum in geology with a relatively high acoustic wave propagation velocity. In the earth's crust, the composition and properties of strata vary, and some of them may have a relatively high acoustic wave propagation velocity. This thin high-velocity layer may be composed of rocks, ores, or other geological materials with high density and hard properties. Due to its relatively fast acoustic wave propagation velocity, the thin high-velocity layer is of certain importance in seismic exploration and geological surveys. By using methods such as acoustic logging, the presence, thickness, and location of the thin high-velocity layer can be detected and measured, so as to better understand the underground structure and geological characteristics. Systematically correcting the depth of VSP is to ensure the accuracy of the depth information of VSP data. Since there are deviations in the measurement of well depth and the placement positions of downhole instruments and equipment may not be completely accurate, it is very important to correct the depth of VSP data. By comparing and correcting with other logging data (such as logging curves), the depth deviation in VSP data can be corrected to match the actual formation depth, so as to obtain a more accurate interpretation of the underground structure and seismic attribute analysis results.
[0048] Preferably, the specific method for correcting the VSP logging velocity in step S4 includes: establishing a linear function using the acoustic logging velocity value, and fitting the VSP logging velocity data to the linear function for correction.
[0049] Preferably, since the sonic logging data is depth-corrected before use, the VSP logging is depth-corrected based on the characteristics of some marker layers of the sonic logging. Specific methods include overall translation or stretching and compression of the VSP logging data. In the case of overall translation of the VSP curve: when there is a certain difference between the overall velocity trend of the sonic logging curve and the VSP curve (for example, the relative error is greater than 200m / s), the VSP curve is overall translated according to the sonic logging curve; in the case of local stretching or compression of the VSP curve: based on the marker layer in the area and combined with the sonic logging curve, when the VSP curve differs from the sonic logging curve in depicting the marker layer (for example, the relative error near the marker layer is greater than 200m / s), the VSP curve is stretched or compressed to adapt to the sonic logging velocity characteristics of the marker layer.
[0050] Example 2
[0051] The present invention also provides a device for correcting VSP data, which adopts the method for correcting VSP data provided in the first embodiment, such as Figure 2 Shown, including:
[0052] Data acquisition module, used to obtain sonic logging data and VSP logging data in the target area;
[0053] An analysis module is used to analyze the sonic logging data and the VSP logging data, identify differences and similarities, and analyze the differences in median values;
[0054] The calculation module is used to calculate the median of VSP logging data and acoustic logging data of different formations and transmit the data to the analysis module;
[0055] Correction module, used to correct the velocity and depth of VSP data.
[0056] Example 3
[0057] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores executable instructions; the processor runs the executable instructions in the memory to implement the method for correcting VSP data provided in the first embodiment.
[0058] Example 4
[0059] The present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for correcting VSP data provided in the first embodiment is implemented.
[0060] The above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the scope of the technical solutions of the present invention, and all of them should be covered by the scope of the claims of the present invention.
Claims
1. A method for correcting VSP data, characterized in that, Including: S1. Based on acoustic logging data, statistically analyze the thickness of thin high-velocity layers in the target area and mark the formation boundary points in the target area; S2. Calculate the median values of VSP logging velocities and acoustic logging velocities for different formations respectively. By comparing the median values of VSP logging velocities and acoustic logging velocities, determine the formations with median values greater than the set threshold for comparative analysis; S3. Based on the median comparison analysis results in step S2, correct the VSP logging velocities, and then reprocess the VSP data to correct the depth of the VSP data.
2. The method according to claim 1, characterized in that, Before statistically analyzing the thickness of thin high-velocity layers in the target area in step S1, it is necessary to determine the accuracy of the acoustic logging data.
3. The method according to claim 2, wherein The accuracy of the acoustic logging data is determined by using the monopole longitudinal wave method and / or the waveform mode search method.
4. The method according to claim 3, characterized in that The monopole longitudinal wave method is used to determine the position of the formation interface; the waveform mode search method is used to determine the boundary between different formations.
5. The method according to claim 1, wherein The VSP logging velocities include pressure wave velocity, shear wave velocity, sonic velocity, temperature, and pressure change velocity.
6. The method according to claim 1, wherein The set threshold in step S2 is 3.
7. The method according to claim 1, wherein The specific method for correcting the VSP logging velocities in step S3 includes: establishing a linear function using the acoustic logging velocity values, and fitting the VSP logging velocity data to the linear function for correction.
8. The method according to claim 1, characterized in that The specific method for correcting the depth of the VSP data in step S3 includes: globally translating, stretching, or compressing the VSP data.
9. An apparatus for correcting VSP data, which adopts the method for correcting VSP data according to any one of claims 1-8, characterized in that Including: A data acquisition module for acquiring acoustic logging data and VSP logging data of the target area; An analysis module for analyzing the acoustic logging data and VSP logging data to determine the difference points and the same points, and for analyzing the difference in median values; A calculation module for calculating the median values of VSP logging data and acoustic logging data for different formations and transmitting the data to the analysis module; A correction module for correcting the velocity and depth of the VSP data.
10. An electronic device, comprising a memory and a processor, the memory storing executable instructions; characterized in that, The processor runs the executable instructions in the memory to implement the method for correcting VSP data according to any one of claims 1-8.
11. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program, when executed by the processor, implements the method for correcting VSP data according to any one of claims 1-8.