Marine seismic data clock drift correction method and device

Abstract

The present application provides a clock drift correction device for marine seismic data, belonging to the technical field of oil exploration seismic data processing. The technical solution provided by the embodiments of the present application, based on the same acquisition time, compares the measured first arrival times and theoretical first arrival times of multiple preset seismic channels at any node to be corrected within the work area, obtains the corresponding relationship between the acquisition time period and the first arrival time difference, and then combines the mathematical expectation corresponding to the first arrival time difference to obtain a second relationship for representing the clock drift static correction amount corresponding to any acquisition time period. This allows clock drift correction to be performed on each seismic channel of the node to be corrected, thereby improving the residual clock drift problem in the data and enhancing data processing quality.

Description

Technical Field

[0001] The present application relates to the technical field of oil exploration seismic data processing, and in particular to a method and device for correcting marine seismic data clock drift. Background Art

[0002] With the advancement of oil and gas exploration technology, seismic exploration has evolved from structural exploration to exploration of complex lithologic reservoirs. Geologists are placing higher demands on the imaging accuracy of seismic data. Onshore "two-width-one-high" seismic exploration technology, with its wider reception azimuth, wider signal bandwidth, and higher excitation-receiver density, has been widely adopted due to its ability to improve data signal-to-noise ratio, resolution, and fidelity through in-house processing. The development of marine observable-noise (OBN) acquisition technology has made "two-width-one-high" offshore acquisition possible, and it will inevitably gradually replace marine streamer acquisition. In submarine OBN seismic exploration, due to node hardware and other factors, as acquisition time increases, the OBN node clock will experience a certain degree of error compared to the actual acquisition time, which in turn affects subsurface imaging. When the jitter frequency is less than 10Hz, this jitter is called drift. Jitter is the short-term fluctuation of the clock signal, which is also known as clock drift. After field data collection is completed, clock drift problems with large time differences are usually corrected. However, some nodes may still have residual clock drift problems, affecting processing quality. Therefore, clock drift correction must be performed on the residual clock drift problems in the data. Summary of the Invention

[0003] The present invention provides a marine seismic data clock drift correction device, which can perform clock drift correction on each seismic channel of the node to be corrected, thereby improving the residual clock drift problem in the data and enhancing the data processing quality. The technical solution is as follows:

[0004] In one aspect, a method for correcting clock drift of marine seismic data is provided, the method comprising:

[0005] For each seismic trace of a node in the work area, pick the first measured first arrival time corresponding to different acquisition times;

[0006] The distances between multiple preset shot points and the node are divided by the average propagation speed of waves in seawater to obtain the theoretical first arrival times of the corresponding multiple preset seismic traces;

[0007] Extracting the second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times;

[0008] Based on the plurality of preset seismic traces, subtracting the second measured first arrival time from the theoretical first arrival time to obtain a first first arrival time difference;

[0009] Obtaining the mathematical expectation of the first arrival time differences corresponding to the plurality of preset seismic traces;

[0010] The portion corresponding to the direct wave in the first first arrival time difference is obtained as the second first arrival time difference;

[0011] Deleting the portion of the second first-arrival time difference that exceeds a preset threshold to obtain a third first-arrival time difference;

[0012] Divide the collection time into multiple collection time periods according to preset durations;

[0013] Get the average first arrival time difference in each acquisition time period;

[0014] Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is fitted;

[0015] Subtracting the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents a clock drift static correction amount corresponding to any acquisition time period;

[0016] Based on the second relationship, the clock drift static correction amount corresponding to the acquisition time period is used to perform clock drift correction on the first measured first arrival time.

[0017] In one possible implementation, after obtaining a first first arrival time difference by subtracting the second measured first arrival time from the theoretical first arrival time based on the plurality of preset seismic traces, the method further includes:

[0018] A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

[0019] In a possible implementation, the preset duration is 12 hours or 24 hours.

[0020] In a possible implementation, after dividing the collection time into a plurality of collection time periods according to a preset duration, the method further includes:

[0021] A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

[0022] In a possible implementation, the first relationship between the acquisition time period and the first arrival time difference is fitted based on the acquisition time period and the corresponding average first arrival time difference, including:

[0023] Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

[0024] In one aspect, a device for correcting clock drift of marine seismic data is provided, the device comprising:

[0025] A picking module is used to pick the first measured first arrival time corresponding to different acquisition times for each seismic trace of a node in the work area;

[0026] A calculation module is used to divide the distances between multiple preset shot points and the node by the average propagation speed of waves in seawater to obtain the theoretical first arrival times of the corresponding multiple preset seismic traces;

[0027] a processing module, configured to extract second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times;

[0028] The calculation module is further configured to calculate the difference between the second measured first arrival time and the theoretical first arrival time based on the plurality of preset seismic traces to obtain a first first arrival time difference;

[0029] A mathematical expectation acquisition module, used to obtain the mathematical expectation of the first arrival time difference corresponding to all the multiple preset seismic traces;

[0030] The processing module is further configured to obtain a portion of the first first arrival time difference corresponding to the direct wave as a second first arrival time difference;

[0031] The processing module is further configured to delete the portion of the second first-arrival time difference that exceeds a preset threshold value to obtain a third first-arrival time difference;

[0032] The processing module is further configured to divide the collection time into a plurality of collection time periods according to a preset duration;

[0033] The calculation module is also used to obtain the average first arrival time difference in each acquisition time period;

[0034] A fitting module, configured to fit a first relationship between the acquisition time period and the first arrival time difference based on the acquisition time period and the corresponding average first arrival time difference;

[0035] The calculation module is further configured to subtract the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents a clock drift static correction amount corresponding to any acquisition time period;

[0036] The correction module is configured to perform clock drift correction on the first measured first arrival time using a clock drift static correction amount corresponding to the acquisition time period based on the second relationship.

[0037] In one possible implementation, the apparatus further includes: a first drawing module, configured to:

[0038] A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

[0039] In a possible implementation, the preset duration is 12 hours or 24 hours.

[0040] In one possible implementation, the apparatus further includes: a second drawing module, configured to:

[0041] A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

[0042] In one possible implementation, the fitting module is configured to:

[0043] Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

[0044] The technical solution provided in the embodiment of the present application is based on the same acquisition time. By comparing the measured first arrival times and theoretical first arrival times of multiple preset seismic channels of any node to be corrected in the work area, the corresponding relationship between the acquisition time period and the first arrival time difference is obtained. Combined with the mathematical expectation corresponding to the first arrival time difference, a second relationship formula for expressing the clock drift static correction amount corresponding to any acquisition time period is obtained, thereby realizing clock drift correction for each seismic channel of the node to be corrected, thereby improving the residual clock drift problem existing in the data and improving the data processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0046] Figure 1 This is a flow chart of a method for correcting marine seismic data clock drift provided by an embodiment of the present application;

[0047] Figure 2 This is a flow chart of a method for correcting marine seismic data clock drift provided by an embodiment of the present application;

[0048] Figure 3 A linear dynamic correction diagram before residual clock drift correction provided by an embodiment of the present application;

[0049] Figure 4 A quality control pie chart of first arrival time difference provided in an embodiment of the present application;

[0050] Figure 5 A scatter plot of the acquisition time period and the first arrival time difference provided in an embodiment of the present application is shown in FIG.

[0051] Figure 6A linear dynamic correction diagram after residual clock drift correction provided by an embodiment of the present application;

[0052] Figure 7 A quality control pie chart of first arrival time difference provided in an embodiment of the present application;

[0053] Figure 8 This is a schematic structural diagram of a marine seismic data clock drift correction device provided in an embodiment of the present application;

[0054] Figure 9 It is a structural diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0056] Figure 1 This is a flow chart of a method for correcting marine seismic data clock drift provided by an embodiment of the present application. Figure 1 , the method can be applied to a computer device, the method comprising:

[0057] 101. For each seismic trace of a node in the work area, pick the first measured first arrival time corresponding to different acquisition times.

[0058] 102. The theoretical first arrival times of the corresponding multiple preset seismic traces are obtained by dividing the distances between the multiple preset shot points and the node by the average propagation speed of the wave in seawater.

[0059] 103. Extract the second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times.

[0060] 104. Based on the plurality of preset seismic traces, the second measured first arrival time is subtracted from the theoretical first arrival time to obtain a first first arrival time difference.

[0061] 105. Obtain the mathematical expectation of the first arrival time differences corresponding to all the preset seismic traces.

[0062] 106. The portion of the first first arrival time difference corresponding to the direct wave is obtained as the second first arrival time difference.

[0063] 107. Delete the portion of the second first arrival time difference that exceeds a preset threshold to obtain a third first arrival time difference.

[0064] 108. Divide the collection time into multiple collection time periods according to the preset duration.

[0065] 109. Obtain the average first arrival time difference within each collection time period.

[0066] 110. Based on the collection time period and the corresponding average first arrival time difference, a first relationship between the collection time period and the first arrival time difference is fitted.

[0067] 111. Subtract the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents the clock drift static correction amount corresponding to any acquisition time period.

[0068] 112. Based on the second relationship, the clock drift static correction value corresponding to the acquisition time period is used to perform clock drift correction on the first measured first arrival time.

[0069] The method provided in the embodiment of the present application is based on the same acquisition time. By comparing the measured first arrival times and theoretical first arrival times of multiple preset seismic channels of any node to be corrected in the work area, the corresponding relationship between the acquisition time period and the first arrival time difference is obtained. Combined with the mathematical expectation corresponding to the first arrival time difference, a second relationship formula for expressing the clock drift static correction amount corresponding to any acquisition time period is obtained, thereby realizing clock drift correction for each seismic channel of the node to be corrected, thereby improving the residual clock drift problem existing in the data and improving the data processing quality.

[0070] In one possible implementation, after obtaining a first first arrival time difference by subtracting the second measured first arrival time from the theoretical first arrival time based on the plurality of preset seismic traces, the method further includes:

[0071] A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

[0072] In a possible implementation, the preset duration is 12 hours or 24 hours.

[0073] In a possible implementation, after dividing the collection time into a plurality of collection time periods according to a preset duration, the method further includes:

[0074] A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

[0075] In a possible implementation, the first relationship between the acquisition time period and the first arrival time difference is fitted based on the acquisition time period and the corresponding average first arrival time difference, including:

[0076] Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

[0077] Figure 2 This is a flow chart of a method for correcting marine seismic data clock drift provided by an embodiment of the present application. Figure 2, the method can be applied to a computer device, the method comprising:

[0078] 201. For each seismic trace of a node in the work area, pick the first measured first arrival time corresponding to different acquisition times.

[0079] In this step, the node is the node where the clock drift correction occurs in the measured first arrival time, and the actual seismic data of the node is first arrived. When picking the first arrival, automatic picking plus manual interactive editing can be used to speed up the efficiency and accuracy of first arrival picking.

[0080] 202. Divide the distances between multiple preset shot points and the node by the average propagation speed of waves in seawater to obtain the theoretical first arrival times of the corresponding multiple preset seismic traces.

[0081] The average propagation velocity of the wave in the seawater can be obtained by averaging the seawater velocity data measured in the work area, or by theoretical calculation, which is not limited in this embodiment.

[0082] In this embodiment, since the number of shot points corresponding to the node is large, each shot point corresponds to a seismic trace, and the clock drift corresponding to different seismic traces of a node at the same acquisition time is the same, multiple representative seismic traces can be obtained, and subsequent calculations are performed based on the theoretical first arrival time of the seismic trace. The results can be used to correct all seismic traces of the node. This method reduces the amount of calculation and improves the calculation efficiency.

[0083] 203. Extract the second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times.

[0084] This step extracts data that is effective for calculation from the first measured first arrival time, which is beneficial to improving calculation efficiency.

[0085] 204. Based on the multiple preset seismic traces, the second measured first arrival time is subtracted from the theoretical first arrival time to obtain a first first arrival time difference.

[0086] In this step, the first arrival time difference can be a positive value, a negative value or zero. Assuming that there is no clock drift problem at the node, the error between the picked first arrival and the theoretical first arrival will only be affected by the change in the wave propagation speed in seawater and the first arrival picking error. The error is usually within ±10ms. By analyzing the first arrival time difference, the degree of first arrival clock drift corresponding to the multiple preset seismic channels can be obtained.

[0087] The data obtained in this step can be found in Figure 3 , Figure 3A linear dynamic correction diagram before residual clock drift correction is provided in an embodiment of the present application. Figure 3 In the figure, the gathers of three adjacent nodes are shown before linear correction using the theoretical first arrival time. The middle node has a clock drift problem. Figure 3 In the figure, the upper curve is the data collection time. It can be seen that the first arrival of the middle node is not horizontal, but is high in the middle and low on both sides.

[0088] 205. Obtain a quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces.

[0089] In this step, the quality control pie chart can be used to control the data quality and ensure the accuracy of the first arrival data. Figure 4 , Figure 4 A quality control pie chart of the first arrival time difference provided in the embodiment of the present application is shown in FIG. Figure 4 In the figure, a circle represents a node. Assuming that the node does not have clock drift problems, the error between the picked first arrival and the theoretical first arrival is only affected by the change in wave propagation speed in seawater and the first arrival picking error. The error is usually within ±10ms, corresponding to Figure 4 For nodes other than those indicated by arrows, the time differences of the first arrivals of the multiple preset seismic traces are evenly distributed about the center of the circle. If there is a clock drift problem at the node, the time difference distribution of the multiple preset seismic traces will no longer be evenly distributed about the center of the circle, such as Figure 4 The node pointed by the arrow, therefore, Figure 4 , we can intuitively see the degree of first arrival clock drift corresponding to the multiple preset seismic traces.

[0090] 206. Obtain the mathematical expectation of the first arrival time differences corresponding to all the multiple preset seismic traces.

[0091] In probability theory and statistics, mathematical expectation is the probability of each possible result in an experiment multiplied by the sum of its results. It is one of the most basic mathematical characteristics and reflects the size of the average value of a random variable. Figure 4 Through such a quality control pie chart, the distribution of the first arrival time difference and the degree of data dispersion of each node can be intuitively analyzed.

[0092] 207. The portion of the first first arrival time difference corresponding to the direct wave is obtained as the second first arrival time difference.

[0093] The first arrival time difference picked up usually includes the first arrival data of the refracted wave. For calculation, by setting the offset range, the first arrival data of the refracted wave and the data with large picking errors are eliminated within the selected offset range, and only the first arrival data of the direct wave is retained to avoid the first arrival time being affected by the refracted wave.

[0094] 208. Delete the portion of the second first arrival time difference that exceeds a preset threshold to obtain a third first arrival time difference.

[0095] The preset threshold can be determined according to the required accuracy of the data. The implementation of this step eliminates data with large errors, so that the third first arrival time difference has higher accuracy.

[0096] 209. Divide the collection time into multiple collection time periods according to preset durations.

[0097] In this embodiment, in order to reduce the difficulty of the subsequent fitting process, the first relationship is made into a linear relationship or a hyperbolic relationship, and the acquisition time is segmented.

[0098] In a possible implementation, the preset time period is 12 hours or 24 hours, ensuring that enough data is contained within the preset time period.

[0099] 210. Draw a scatter plot based on the collection time period and the corresponding third first arrival time difference.

[0100] In this step, a scatter plot is drawn with the horizontal axis representing the acquisition time period and the vertical axis representing the third first arrival time difference. Figure 5 , Figure 5 A scatter plot of the acquisition time period and the first arrival time difference provided in an embodiment of the present application is shown in the figure. From this figure, the degree of discreteness of this set of data can be intuitively seen. Furthermore, based on the scatter plot, points with large deviations in the figure can be removed to ensure that the data has high accuracy.

[0101] 211. Get the average first arrival time difference within each collection time period.

[0102] In steps 209-211, the acquisition time is segmented to obtain the average first arrival time difference in each acquisition time period. This reduces the amount of data that needs to be fitted and the difficulty of the fitting process, so that the first relationship obtained is a linear relationship or a hyperbolic relationship with a simple relationship structure, which is easy to use.

[0103] 212. Based on the collection time period and the corresponding average first arrival time difference, a linear fitting or a hyperbola fitting is used to obtain a first relationship between the collection time period and the first arrival time difference.

[0104] In this step, if linear fitting is used, the structure of the first relationship obtained is:

[0105] dT=a(t-t0)+b (1)

[0106] If hyperbola fitting is used, the structure of the first relational equation is:

[0107] dT=a(t-t0) 2 +b (2)

[0108] In equations (1) and (2), T represents the acquisition time period;

[0109] dT represents the time difference between the picked first arrival and the theoretical first arrival;

[0110] t represents the acquisition time;

[0111] t0 represents the acquisition time when dT = 0;

[0112] a and b represent constants that need to be obtained through fitting.

[0113] 213. Subtract the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents the clock drift static correction amount corresponding to any acquisition time period.

[0114] In this step, the clock drift static correction value corresponding to any acquisition time period can be expressed by the following formula (3):

[0115] S drift =dT-T0 (3)

[0116] Among them, S drift Indicates the clock drift static correction value corresponding to the acquisition time period T;

[0117] dT represents the time difference between the picked first arrival and the theoretical first arrival;

[0118] T0 represents the mathematical expectation obtained in step 206 .

[0119] 214. Based on the second relationship, the clock drift static correction value corresponding to the acquisition time period is used to perform clock drift correction on the first measured first arrival time.

[0120] In the work area, each channel in the node corresponds to a first measured first arrival time. Based on the corresponding acquisition time period, the corresponding clock drift static correction value is obtained through the second relationship, so as to perform clock drift correction.

[0121] The data obtained in this step can be found in Figure 6 , Figure 6 A linear dynamic correction diagram after residual clock drift correction provided by an embodiment of the present application is provided. Figure 6 In the figure, the three adjacent nodes are linearly corrected using the theoretical first arrival time. The upper curve is the data acquisition time, and the middle node has a clock drift problem before correction. Figure 3In the figure, it can be seen that the initial arrival of the middle node is not horizontal, but there is a phenomenon that the middle is high and the two sides are low. Figure 6 In the , the first arrivals are corrected to be horizontal and consistent with the shape of the adjacent first arrivals.

[0122] In this step, see Figure 7 , Figure 7 A quality control pie chart of the first arrival time difference provided in the embodiment of the present application is shown in FIG. Figure 7 In the , a circle represents a node, see Figure 7 The node pointed by the arrow. Figure 3 In the example, the time difference distribution of the multiple preset seismic traces is not uniformly distributed about the center of the circle. Therefore, after correction, Figure 7 In the data, the difference between the picked first arrival time and the theoretical first arrival time decreases, and the time difference with the surrounding nodes tends to be consistent, proving that the residual clock drift problem in the data has been solved.

[0123] All of the above optional technical solutions can be combined in any way to form optional embodiments of the present application, and will not be described in detail here.

[0124] The method provided in the embodiment of the present application is based on the same acquisition time. By comparing the measured first arrival times and theoretical first arrival times of multiple preset seismic channels of any node to be corrected in the work area, the corresponding relationship between the acquisition time period and the first arrival time difference is obtained. Combined with the mathematical expectation corresponding to the first arrival time difference, a second relationship formula for expressing the clock drift static correction amount corresponding to any acquisition time period is obtained, thereby realizing clock drift correction for each seismic channel of the node to be corrected, thereby improving the residual clock drift problem existing in the data and improving the data processing quality.

[0125] Figure 8 This is a schematic diagram of the structure of a marine seismic data clock drift correction device provided by an embodiment of the present application, see Figure 8 , the device comprises:

[0126] The picking module 801 is used to pick the first measured first arrival time corresponding to different acquisition times for each seismic trace of a node in the work area;

[0127] A calculation module 802 is configured to divide the distances between the plurality of preset shot points and the node by the average propagation velocity of the wave in seawater to obtain the theoretical first arrival times of the corresponding plurality of preset seismic traces;

[0128] The processing module 803 is configured to extract the second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times;

[0129] The calculation module 802 is further configured to calculate the difference between the second measured first arrival time and the theoretical first arrival time based on the plurality of preset seismic traces to obtain a first first arrival time difference;

[0130] A mathematical expectation acquisition module 804 is used to acquire the mathematical expectation of the first arrival time differences corresponding to all the preset seismic traces;

[0131] The processing module 803 is further configured to obtain a portion of the first first arrival time difference corresponding to the direct wave as a second first arrival time difference;

[0132] The processing module 803 is further configured to delete the portion of the second first-arrival time difference that exceeds a preset threshold to obtain a third first-arrival time difference;

[0133] The processing module 803 is further configured to divide the collection time into a plurality of collection time periods according to a preset duration;

[0134] The calculation module 802 is further used to obtain the average first arrival time difference in each acquisition time period;

[0135] A fitting module 805 is configured to fit a first relationship between the acquisition time period and the first arrival time difference based on the acquisition time period and the corresponding average first arrival time difference;

[0136] The calculation module 802 is further configured to subtract the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents a clock drift static correction amount corresponding to any acquisition time period;

[0137] The correction module 806 is configured to perform clock drift correction on the first measured first arrival time using the clock drift static correction amount corresponding to the acquisition time period based on the second relationship.

[0138] In one possible implementation, the apparatus further includes: a first drawing module, configured to:

[0139] A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

[0140] In a possible implementation, the preset duration is 12 hours or 24 hours.

[0141] In one possible implementation, the apparatus further includes: a second drawing module, configured to:

[0142] A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

[0143] In one possible implementation, the fitting module 805 is configured to:

[0144] Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

[0145] The device provided in the embodiment of the present application obtains the corresponding relationship between the acquisition time period and the first arrival time difference by comparing the measured first arrival time and the theoretical first arrival time of multiple preset seismic channels of any node to be corrected in the work area based on the same acquisition time. Then, combined with the mathematical expectation corresponding to the first arrival time difference, a second relationship for expressing the clock drift static correction amount corresponding to any acquisition time period is obtained, thereby realizing clock drift correction for each seismic channel of the node to be corrected, thereby improving the residual clock drift problem existing in the data and improving the data processing quality.

[0146] It should be noted that the marine seismic data clock drift correction device provided in the above embodiment is only illustrated by the division of the above-mentioned functional modules when correcting marine seismic data clock drift. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the marine seismic data clock drift correction device provided in the above embodiment and the marine seismic data clock drift correction method embodiment are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0147] Figure 9 9 is a schematic diagram of the structure of a computer device provided in an embodiment of the present application. The computer device 900 may vary significantly due to different configurations or performances, and may include one or more processors (central processing units, CPUs) 901 and one or more memories 902. The memories 902 store at least one program code, which is loaded and executed by the processors 901 to implement the methods provided in the above-mentioned various method embodiments. Of course, the computer device may also have components such as a wired or wireless network interface, a keyboard, and input / output interfaces for input and output. The computer device may also include other components for implementing device functions, which will not be described in detail here.

[0148] In some embodiments, the computer program involved in the embodiments of the present application may be deployed and executed on a computer device, or on multiple computer devices located at one location, or on multiple computer devices distributed at multiple locations and interconnected through a communication network. Multiple computer devices distributed at multiple locations and interconnected through a communication network may constitute a blockchain system.

[0149] In an exemplary embodiment, a computer-readable storage medium is also provided, such as a memory including program code. The program code can be executed by a processor in a computer device to implement the marine seismic data clock drift correction method of the above embodiment. For example, the computer-readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, or an optical data storage device.

[0150] Those skilled in the art will understand that all or part of the steps for implementing the above embodiments may be accomplished by hardware, or may be accomplished by instructing the relevant hardware through a program, and the above program may be stored in a computer-readable storage medium, which may be a read-only memory, a disk, or an optical disk, etc.

[0151] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for correcting clock drift of marine seismic data, characterized in that: The method comprises: For each seismic trace of a node in the work area, pick the first measured first arrival time corresponding to different acquisition times; Dividing the distances between the multiple preset shot points and the node by the average propagation speed of the wave in the seawater, to obtain the theoretical first arrival times of the corresponding multiple preset seismic traces; Extracting the second measured first arrival times corresponding to the plurality of preset seismic traces from the first measured first arrival times; Based on the plurality of preset seismic traces, subtracting the second measured first arrival time from the theoretical first arrival time to obtain a first first arrival time difference; Obtaining the mathematical expectation of the first arrival time differences corresponding to the plurality of preset seismic traces; The portion corresponding to the direct wave in the first first arrival time difference is obtained as the second first arrival time difference; Deleting the portion of the second first-arrival time difference that exceeds a preset threshold to obtain a third first-arrival time difference; Divide the acquisition time into multiple acquisition time periods according to preset durations; Get the average first arrival time difference in each acquisition time period; Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is fitted; Subtracting the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents a clock drift static correction amount corresponding to any acquisition time period; Based on the second relationship, clock drift correction is performed on the first measured first arrival time using the clock drift static correction amount corresponding to the acquisition time period.

2. The method according to claim 1, characterized in that After obtaining a first first arrival time difference by subtracting the second measured first arrival time from the theoretical first arrival time based on the plurality of preset seismic traces, the method further includes: A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

3. The method according to claim 1, characterized in that The preset duration is 12 hours or 24 hours.

4. The method according to claim 1, wherein After dividing the acquisition time into a plurality of acquisition time periods according to a preset duration, the method further includes: A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

5. The method according to claim 1, wherein The first relationship between the acquisition time period and the first arrival time difference is fitted based on the acquisition time period and the corresponding average first arrival time difference, including: Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

6. A clock drift correction device for marine seismic data, characterized in that: The device comprises: A picking module is used to pick the first measured first arrival time corresponding to different acquisition times for each seismic trace of a node in the work area; a calculation module, configured to divide the distances between the plurality of preset shot points and the node by the average propagation velocity of the wave in seawater to obtain theoretical first arrival times of the corresponding plurality of preset seismic traces; a processing module, configured to extract, from the first measured first arrival times, second measured first arrival times corresponding to the plurality of preset seismic traces; The calculation module is further configured to calculate, based on the plurality of preset seismic traces, a difference between the second measured first arrival time and the theoretical first arrival time to obtain a first first arrival time difference; A mathematical expectation acquisition module, configured to acquire the mathematical expectations of the first arrival time differences corresponding to all of the plurality of preset seismic traces; The processing module is further configured to obtain a portion of the first first arrival time difference corresponding to the direct wave as a second first arrival time difference; The processing module is further configured to delete the portion of the second first-arrival time difference that exceeds a preset threshold to obtain a third first-arrival time difference; The processing module is further configured to divide the acquisition time into a plurality of acquisition time periods according to a preset duration; The calculation module is also used to obtain the average first arrival time difference in each acquisition time period; A fitting module, configured to fit a first relationship between the acquisition time period and the first arrival time difference based on the acquisition time period and the corresponding average first arrival time difference; The calculation module is further configured to subtract the mathematical expectation from the first relational expression to obtain a second relational expression, where the second relational expression represents a clock drift static correction amount corresponding to any acquisition time period; The correction module is used to perform clock drift correction on the first measured first arrival time based on the second relationship using the clock drift static correction amount corresponding to the acquisition time period.

7. The device according to claim 6, characterized in that The device further includes a first drawing module, configured to: A quality control pie chart of the first arrival time differences corresponding to the plurality of preset seismic traces is obtained.

8. The device according to claim 6, characterized in that The preset duration is 12 hours or 24 hours.

9. The device according to claim 6, characterized in that The device further includes a second drawing module, configured to: A scatter plot is drawn based on the acquisition time period and the corresponding third first arrival time difference.

10. The device according to claim 6, characterized in that The fitting module is used to: Based on the acquisition time period and the corresponding average first arrival time difference, a first relationship between the acquisition time period and the first arrival time difference is obtained by using linear fitting or hyperbola fitting.

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