A method and system for obtaining sliding time in vibroseis aliasing acquisition

Abstract

Embodiments of the present application relate to the technical field of oil seismic exploration, and provide a method and system for obtaining sliding time corresponding to the distance between different vibrators in controllable vibrator aliasing acquisition, to solve the problem that the sliding time determined by artificial qualitative judgment is not accurate enough. A plurality of single-shot pre-correlation data and a plurality of force signal data generated when a plurality of test points perform seismic experiments, and environmental noise data are obtained. The plurality of single-shot pre-correlation data and the environmental noise data are preprocessed to obtain single-shot post-correlation data corresponding to the plurality of single-shot pre-correlation data respectively. Based on a preset distance and the plurality of single-shot post-correlation data, harmonic interference data corresponding to different sliding times of the plurality of single-shot pre-correlation data within a preset time range is determined. The harmonic interference is suppressed according to the plurality of force signal data to obtain a plurality of suppressed data. The sliding time within the preset distance is determined based on the plurality of single-shot post-correlation data, preset acquisition parameters and the plurality of suppressed data.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of petroleum seismic exploration, and more specifically, to a method and system for acquiring sliding time during vibroseis aliasing acquisition. Background Art

[0002] Seismic exploration is an important method for finding oil and natural gas. An important task in seismic data acquisition is to artificially excite seismic waves. As seismic acquisition technology develops towards high density, wide bandwidth, and wide azimuth ("two wides and one high"), the highly efficient mixed acquisition technology of controllable vibroseis (also known as mixed acquisition) provides technical support for the economic feasibility of "two wides and one high" seismic acquisition.

[0003] High-efficiency aliasing acquisition inevitably introduces interference from adjacent shots (also known as high-efficiency acquisition noise). When high-efficiency aliasing acquisition is employed, high-efficiency acquisition noise includes interference from adjacent shot harmonics, first arrivals, direct waves, and surface waves. These high-efficiency acquisition noises can be minimized by designing sliding time and source spacing rules (time-distance rules), balancing raw data quality and acquisition efficiency. Therefore, determining the appropriate sliding time is crucial for improving raw data quality and acquisition efficiency. However, existing techniques often rely on manual qualitative analysis to determine the degree of adjacent shot interference under different source spacing and sliding time conditions, resulting in inaccurately determined sliding times. Summary of the Invention

[0004] The embodiments of the present application provide a method and system for obtaining the sliding time during vibroseis aliasing acquisition, aiming to solve the problem that the sliding time determined by manual qualitative judgment is not accurate enough.

[0005] A first aspect of an embodiment of the present application provides a sliding time acquisition method, the acquisition method comprising:

[0006] Acquiring a plurality of single-shot correlation pre-data and a plurality of force signal data generated when conducting seismic experiments at a plurality of test points on a test line, and acquiring environmental noise data on the test line;

[0007] The plurality of single-shot pre-correlation data and the environmental noise data are processed in a preset manner to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes noise post-correlation data;

[0008] Determining, based on a preset distance and a plurality of the single-shot correlation data, first harmonic interference data corresponding to different sliding times within a preset time range for a plurality of the single-shot correlation data before the single-shot correlation; and performing harmonic suppression on the first harmonic interference according to the plurality of the force signal data to obtain a plurality of first suppressed data; wherein the preset distance is the production arrangement length of the test work area;

[0009] Based on the plurality of single-shot related post-data, preset acquisition parameters and the plurality of first post-suppression data, a first sliding time corresponding to the preset distance is determined.

[0010] Optionally, obtaining a plurality of single-shot related pre-data and a plurality of force signal data generated when performing seismic experiments at a plurality of test points on a test line includes:

[0011] Determine the test line position and the number of test points according to the surface conditions of the work area, and determine the test point positions according to the test line position;

[0012] Determining the excitation parameters and scanning signal parameters, and controlling the plurality of controllable vibrators to perform a single-unit single-excitation seismic experiment at the test point;

[0013] Based on the preset acquisition parameters, the single shot related pre-data and the force signal data of each of the multiple test points are acquired to obtain the multiple single shot related pre-data and the multiple force signal data.

[0014] Optionally, based on a preset distance and a plurality of the single-shot post-correlation data, determining first harmonic interference data corresponding to different sliding times of a plurality of the single-shot pre-correlation data within a preset time range includes:

[0015] Based on the preset distance and the multiple single shot correlation data, a preset time range for extracting the first harmonic interference is determined.

[0016] Based on the multiple single-shot correlation data, the first harmonic interference corresponding to different sliding times in the preset time range is obtained.

[0017] Optionally, determining a first sliding time corresponding to the preset distance based on the plurality of single-shot related post-data, preset acquisition parameters, and the plurality of first post-suppression data includes:

[0018] Based on the plurality of noise-correlated data and preset acquisition parameters, obtaining first thresholds of the plurality of first suppressed data;

[0019] Determining first root mean square energy values ​​of a plurality of the second harmonic interferences based on data other than the noise-correlated data in the single-shot correlated data, so as to obtain corresponding curves of the first root mean square energy values ​​and sliding time corresponding to respective test points;

[0020] Obtaining intervals on each of the corresponding curves where the first root mean square energy value is less than the first threshold, and determining the minimum value of the sliding time in each of the intervals as the first preset sliding time at each test point;

[0021] A maximum value among a plurality of first preset sliding times is determined as the first sliding time.

[0022] Optionally, the acquiring of a first threshold value of a plurality of the first post-suppression data based on the plurality of the single-shot related post-data and preset acquisition parameters includes:

[0023] Based on the plurality of preset acquisition parameters, determining the energy statistical time window range of each of the background noise energies corresponding to the plurality of single-shot correlation data, and the offset distance of each of the energy statistical time window ranges;

[0024] Determining the noise data of each of the single shot correlation data within the respective energy statistical time windows according to the offset distances corresponding to the respective energy statistical time windows, thereby determining the background noise energy values ​​within the plurality of energy statistical time windows;

[0025] An energy average is determined according to the multiple background noise energy values, and the energy average is determined as the first threshold.

[0026] Optionally, the acquisition method further includes:

[0027] For the relevant post-shot data of this single shot, perform the following steps:

[0028] Determine the minimum synchronization distance outside the preset distance based on the first arrival time of the single shot correlation data, the preset distance, and the preset maximum reflection time of the target layer;

[0029] Perform a dynamic sliding test simulation based on the correlated data to obtain second harmonic interference;

[0030] performing harmonic suppression on the second harmonic interference according to the force signal data to obtain second suppressed data;

[0031] The second sliding time corresponding to different preset source spacings within the range from the preset distance to the minimum synchronization distance is determined based on the single shot correlation data, the acquisition parameters, the minimum synchronization distance and the second suppressed data.

[0032] Optionally,

[0033] The acquisition method further includes:

[0034] Determine, based on each shot-correlated data, a second root mean square energy value of the shot-correlated data within a preset time range, and a noise root mean square energy value within the preset time range;

[0035] determining a harmonic interference radius of each single shot correlation data according to the second root mean square energy value and the root mean square average energy value;

[0036] Dynamic sliding test simulation is performed based on the single-shot correlation data corresponding to the largest harmonic interference radius among the single-shot correlation data.

[0037] Optionally,

[0038] The method further comprises:

[0039] Determining a second preset sliding time corresponding to each adjacent gun interference type among a plurality of other adjacent gun interference types; wherein the plurality of other adjacent gun interference types at least include a rear gun first arrival wave interference, a front gun surface wave interference, and a front gun direct arrival wave interference;

[0040] The one with the largest value among the plurality of second preset sliding times is determined as the second sliding time.

[0041] Optionally, the method further includes:

[0042] Calibrate the sliding time corresponding to the minimum synchronization distance to a preset value;

[0043] The time-distance rule curve is determined according to the preset distance, the minimum synchronization distance, the first sliding time, the second sliding time, and the preset value.

[0044] A second aspect of an embodiment of the present application provides a time-distance regular curve acquisition system, comprising:

[0045] an acquisition module, configured to acquire a plurality of single-shot correlation pre-data and a plurality of force signal data generated when a seismic experiment is performed on a plurality of test points on a test line, and to acquire environmental noise data on the test line;

[0046] a preset processing module, configured to perform preset processing on the plurality of single-shot pre-correlation data and the environmental noise data to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes noise post-correlation data;

[0047] A suppression module is used to determine, based on a preset distance and a plurality of the single-shot related data, the first harmonic interference data corresponding to different sliding times within a preset time range of the plurality of the single-shot related data; and to perform harmonic suppression on the first harmonic interference according to the plurality of the force signal data to obtain a plurality of first suppressed data; wherein the preset distance is the production arrangement length of the test work area.

[0048] A determination module is configured to determine, based on the plurality of single-shot correlation data, preset acquisition parameters, and the plurality of first and second suppression data, a first sliding time within the preset distance and a second sliding time corresponding to different preset source spacings from the preset distance to the minimum synchronization distance; and determine the time-distance rule curve according to the preset distance, the minimum synchronization distance, the first sliding time, the second sliding time, and the preset value.

[0049] A sliding time acquisition method provided by the present application is used to conduct seismic experiments on different test points in the test site, thereby obtaining data on seismic tests at different terrains of the test site, including single-shot pre-correlation data, force signal data, and environmental noise data of each test point. By performing preset processing, i.e., correlation processing, on the single-shot pre-correlation data and environmental noise data representing time and amplitude, corresponding single-shot post-correlation data are obtained. Based on the single-shot post-correlation data of each test point, the first and second harmonic interference data representing time and energy of each test point are obtained. Then, the first and second harmonic interference data are suppressed according to the force signal data to obtain multiple The first and second suppressed data of the test point are then used, based on the first suppressed data after harmonic suppression to eliminate harmonic interference, and the preset distance, to determine the first sliding time when the distance between the earthquake sources is less than the preset distance; based on the first arrival wave time of the single-shot correlation data, the preset distance, and the preset maximum reflection time of the target layer, the minimum synchronization distance outside the preset distance is determined; based on the second suppressed data and the interference influence range of the adjacent shot interference waves, the second sliding time when the distance between the earthquake sources is between the preset distance and the minimum synchronization distance is determined. By eliminating harmonic interference in the seismic experiment and quantitatively evaluating the interference range of adjacent shots, a more accurate sliding time is obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. 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.

[0051] Figure 1 This is a schematic diagram of the surface structure proposed in a specific embodiment of the present application;

[0052] Figure 2 This is a flowchart of the steps of the acquisition method proposed in one embodiment of the present application;

[0053] Figure 3 2 is a schematic diagram of a background noise energy statistical time window proposed in a specific embodiment of the present application;

[0054] Figure 4 This is a comparison diagram before and after force signal suppression proposed in a specific embodiment of the present application;

[0055] Figure 5 This is a flowchart of the steps for obtaining relevant previous data proposed in one embodiment of the present application;

[0056] Figure 6 This is a flowchart of the steps for obtaining the first harmonic interference proposed in one embodiment of the present application;

[0057] Figure 7 This is a flowchart of the steps for determining the first sliding time proposed in one embodiment of the present application;

[0058] Figure 8 This is a flowchart of the steps for determining a first threshold value proposed in one embodiment of the present application;

[0059] Figure 9 This is a flowchart of the steps for determining the second sliding time proposed in an embodiment of the present application;

[0060] Figure 10 This is a flowchart of the steps for confirming the harmonic interference radius proposed in one embodiment of the present application;

[0061] Figure 11 is a flowchart of steps for determining a second sliding time proposed in another embodiment of the present application;

[0062] Figure 12 This is a flowchart of the steps for determining a time-distance regular curve proposed in one embodiment of the present application;

[0063] Figure 13 This is a schematic diagram of multiple background noise energy values ​​proposed in a specific embodiment of the present application;

[0064] Figure 14 This is a corresponding curve diagram of sliding time at three test points proposed in a specific embodiment of the present application;

[0065] Figure 15 This is a diagram for determining the harmonic interference radius proposed in a specific embodiment of the present application;

[0066] Figure 16 Schematic diagram of the harmonic interference and first arrival interference of the rear gun on the front gun proposed in a specific embodiment of the present application;

[0067] Figure 17 This is a graph showing the correspondence between the sliding time and the harmonic energy value under the condition of post-shot harmonic interference proposed in a specific embodiment of the present application;

[0068] Figure 18 Schematic diagram of front shot surface wave interference proposed in a specific embodiment of the present application;

[0069] Figure 19is a schematic diagram of the interference of the record of the later shot by the surface wave of the former shot according to an embodiment of the present application;

[0070] Figure 20 is a ratio diagram of the energy value of the interference of the later shot to the energy of the surface wave of the former shot according to an embodiment of the present application;

[0071] Figure 21 is a schematic diagram of the interference of the direct wave of the former shot according to an embodiment of the present application;

[0072] Figure 22 is a schematic diagram of the interference of the record of the later shot by the direct wave of the former shot according to an embodiment of the present application;

[0073] Figure 23 is a ratio diagram of the energy value of the interference of the later shot to the energy of the direct wave of the former shot according to an embodiment of the present application;

[0074] Figure 24 is a time-distance regular curve diagram according to an embodiment of the present application. DETAILED DESCRIPTION

[0075] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0076] Seismic exploration is an important method for finding oil and natural gas, and an important work of seismic data acquisition is to artificially excite seismic waves. The excitation sources and methods used are various. Land seismic data acquisition mainly uses two kinds of excitation sources, i.e., explosives and a controllable source. With the development of seismic acquisition technology in the direction of high density, wide frequency band and wide azimuth (two wide and one high), the controllable source high-efficiency aliasing acquisition (also called mixed acquisition) technology provides technical support for the economic feasibility of two wide and one high seismic acquisition. Sliding scanning is to simultaneously use multiple controllable sources to excite with a certain time interval, and the next group of sources can start to excite without waiting for the vibration of the previous group of sources to be completed. The time interval between the excitation of the two groups of sources is called sliding time.

[0077] A vibrator system consists of three components: a sweep signal generator, a source, and a correlator. When using a vibrator for seismic data acquisition, the sweep signal generator first generates a long electrical signal with uniform amplitude and gradually changing frequency, called a sweep signal. The source control box converts the sweep signal into mechanical vibrations of the plate and hammer through a hydraulic system. This mechanical vibration is then propagated underground through the ground in contact with the plate and is received by a detector. Harmonic interference is an inevitable phenomenon during vibrator construction, and its causes can be categorized into two types: mechanical interference with the vibrator and coupling between the source and the surface. Harmonics have a relatively stable formation pattern, and their intensity is related to factors such as the surface conditions in the work area and the distortion of the source system.

[0078] In the existing technology, the dynamic sliding scanning time interval rule is designed by performing frequency scanning on a single shot of the source acquisition test with different source spacings and sliding times on site, and manually qualitatively judging the degree of interference between adjacent shots under different source spacings and sliding times, resulting in the determined sliding time being inaccurate.

[0079] In view of this, the present application proposes a method and system for acquiring sliding time during vibroseis aliasing acquisition.

[0080] Example 1

[0081] Reference Figure 1 As shown, a specific application scenario diagram of the present application is shown, such as Figure 1 As shown in the figure, the range enclosed by the outermost rectangular frame, which includes three surface conditions, is the test area of ​​this test. These three surface conditions include saline-alkali area, desert area and Gobi area. A test point for the vibration test of the seismic source is set at each surface condition, and the test line is located between each test point.

[0082] When conducting earthquake experiments in practice, it is necessary to stimulate two earthquake sources in sequence according to the appropriate sliding time. The sliding time is determined by the interval between the earthquake sources, for example Figure 1 In the process, before conducting seismic experiments at the test points on both sides, an experiment to determine the sliding time is required. By exciting the source at the test points with different surface conditions, relevant data is obtained, and then the data is processed. Based on the data related to harmonic interference in the relevant processed data, the sliding time at which there will be no impact between the two sources is obtained.

[0083] The first embodiment of the present application proposes a sliding time acquisition method, referring to Figure 2 , shows a flowchart of the steps of the sliding time acquisition method of the present application, the acquisition method includes the following steps:

[0084] S1, obtaining a plurality of single shot correlation pre-data and a plurality of force signal data generated when conducting seismic experiments at a plurality of test points on a test line, and obtaining environmental noise data on the test line.

[0085] exist Figure 1 In the figure, the outermost range including the three surface conditions is the test area of ​​this test. A test point for the vibration test of the seismic source is set at each surface condition, and the test line is located between each test point.

[0086] First, a test line is arranged in the test area. The test line is composed of several detectors arranged at preset intervals. The test line is located between various test points. During the test, vibrations are emitted into the underground at the test points through the seismic source. Then, the geophones on the test line obtain data such as reflected waves of the underground structure according to certain acquisition parameters. The data of each geophone are then collected to obtain the relevant pre-data of a single shot in this test. At the same time, the force signal data of the seismic source at each test point in this test is obtained for the subsequent elimination of harmonic interference from adjacent shots.

[0087] At the same time, the environmental noise data on the entire test line is collected, that is, the natural noise data in the underground environment detected by each detector in the experiment. The environmental noise data is preset together with the single-shot pre-correlation data of each test point collected on the test line, that is, correlation processing is performed to obtain the single-shot post-correlation data.

[0088] S2, performing preset processing on the plurality of single-shot pre-correlation data and the environmental noise data to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes noise post-correlation data.

[0089] The process of pre-processing multiple single-shot related front data and environmental noise data can be as follows: First, the scanning signal length T s Fill to the length T of the data before the single shot correlation b

[0090]

[0091] Then the pre-correlation data of the completed single shot is processed according to the following formula, that is, correlation processing, and the environmental noise is also correlated to obtain, for example Figure 3 The single shot correlation data,

[0092]

[0093] Where f represents the scanning signal; M represents the number of scanning signal samples, M = T s / Δt+1; N1 represents the number of data samples before the single shot correlation N1=T b / Δt+1;Ntrc represents the number of single shot channels; f' represents the scan signal after filling; S represents the data before single shot correlation; S' represents the data after single shot correlation; Δt is the sampling time interval.

[0094] Among them, the noise correlation data is located within the single shot correlation data, for example Figure 3 The data in the middle rectangle.

[0095] S3, based on the preset distance and multiple single-shot related data, determine the first harmonic interference data corresponding to different sliding times of multiple single-shot related data within a preset time range; and perform harmonic suppression on the first harmonic interference according to multiple force signal data to obtain multiple first suppressed data; wherein the preset distance is the production arrangement length of the test work area.

[0096] The preset distance is determined based on the arrangement length of the test line in the previously determined test area, that is, the distance between two adjacent seismic sources when conducting subsequent related experiments.

[0097] Since the interference effect of the harmonics of the subsequent shots on the data of the preceding shots is mainly considered within the preset distance, the harmonic interference of one earthquake source on another earthquake source is different due to different sliding times. Therefore, the preset time range of each test point is first determined, and then the first harmonic interference data corresponding to each sliding time within the preset time range is determined.

[0098] For example Figure 4 By using the force signal obtained from the test point corresponding to each first harmonic interference data, harmonic suppression is performed on each first harmonic interference data, eliminating the influence of the test point's source itself. This results in more accurate first suppressed data, i.e., more accurate single-shot correlation data. The rectangular section in the left figure (before harmonic interference suppression) represents the portion from which the first harmonic interference data was extracted, while the rectangular section in the right figure (after harmonic interference suppression) represents the corresponding first suppressed data.

[0099] S4, determining a first sliding time corresponding to a preset distance based on a plurality of single-shot related post-data, preset acquisition parameters, and a plurality of first post-suppression data.

[0100] Among them, the preset acquisition parameters include the scanning frequency, scanning length, driving amplitude, start and end slopes, sampling interval, time length of single-shot correlation data before and after the single-shot correlation data when obtaining single-shot correlation data and environmental noise data, as well as the track spacing and number of receiving tracks in the test line.

[0101] According to multiple single-shot correlation data, preset acquisition parameters, including noise correlation data and preset distance, etc., based on the more accurate first suppressed data of multiple test points after harmonic suppression, and then by analyzing the harmonic interference effects of different sliding times in the first suppressed data, the sliding time of multiple test points is determined, and the most appropriate sliding time within the preset distance determined by the current work area is determined, that is, the first sliding time.

[0102] By conducting seismic experiments on different test points in the test site, data on seismic tests at different terrains of the test site are obtained, including single-shot pre-correlation data, force signal data and environmental noise data of each test point. By performing preset processing, that is, correlation processing, on the single-shot pre-correlation data and environmental noise data representing time and amplitude, corresponding single-shot post-correlation data are obtained. According to the single-shot post-correlation data of each test point, first harmonic interference data representing time and energy of each test point are obtained. Then, the first harmonic interference data is suppressed according to the force signal data to obtain first suppressed data of multiple test points. Then, based on the first suppressed data after harmonic suppression to eliminate harmonic interference, and the preset distance, the first sliding time when the distance between the earthquake sources is less than the preset distance is determined. By eliminating harmonic interference, a more accurate sliding time is obtained.

[0103] In some embodiments, reference Figure 5 , shows a flowchart of the steps for obtaining single shot pre-correlation data, wherein obtaining multiple single shot pre-correlation data and multiple force signal data generated when performing seismic experiments at multiple test points on a test line includes the following steps:

[0104] S101, determining the test line position and the number of test points according to the surface conditions of the work area, and determining the test point positions according to the test line position.

[0105] Before the test, considering the surface and underground seismic geological conditions, different surface types of survey lines in the work area were selected as the test line locations, for example Figure 1 If the work area contains three surface types, a test point is set at each of the three surface types. If the surface conditions in the work area are complex and a single test line cannot cover all of the surface areas, additional test lines should be laid out on other surfaces for testing. A single test line is used for reception, and the track spacing is consistent with the observation track spacing in the work area.

[0106] S102, determining excitation parameters and scanning signal parameters, and controlling multiple vibrators to perform a single-unit single-shot seismic experiment at a test point.

[0107] Among them, the number of seismic sources is selected according to the number of test points. Experiments are carried out at each test point through a seismic source. The excitation parameters of the seismic source and the scanning signal parameters of the vibration wave emitted by the seismic source are determined according to the experimental requirements and actual geological conditions. During the test, the seismic source is set at the test point respectively, and a single-unit single-excitation earthquake experiment is carried out at the test point according to the excitation parameters.

[0108] S103 , based on preset acquisition parameters, acquiring the single shot correlation pre-data and force signal data of each of the multiple test points to obtain a plurality of single shot correlation pre-data and a plurality of force signal data.

[0109] By adopting preset acquisition parameters, the vibration waves reflected from the underground are received and analyzed, and the single-shot related pre-data of each test at each test point and the force signal data of each source test are obtained.

[0110] In some embodiments, reference Figure 6 , shows a flowchart of the steps of obtaining the first harmonic interference, wherein, based on a preset distance and multiple single-shot correlation data, determining the first harmonic interference data corresponding to different sliding times within a preset time range of multiple single-shot correlation data, includes:

[0111] S201 : Determine a preset time range for extracting the first harmonic interference based on a preset distance and multiple single-shot correlation data.

[0112] The preset process may include the following steps:

[0113] First, the scanning signal length T s Fill to the relevant data length T b , f represents the scanning signal, f' represents the scanning signal after filling

[0114]

[0115] Therefore, the preset time range may be the time range of the single shot correlation data.

[0116] S202 , based on the correlated data of multiple single shots, obtain the first harmonic interference corresponding to different sliding times within a preset time range.

[0117] According to different sliding time ST k Extract the first harmonic interference H within the time range of the data after single shot correlation k , N1 represents the number of points recorded before the correlation N1 = T b / Δt+1;N trc Indicates the number of single gun channels,

[0118] H k=S'(i,j)i=nt,nt+1,…,nt+N1-M j=1,2,…,N trc

[0119] Where H k Indicates the sliding time ST k The first harmonic interference in the data time range after the previous shot correlation; nt = N1-ST k / Δt, Δt is the sampling time interval.

[0120] In some embodiments, reference Figure 7 , a flowchart of the steps of determining the first sliding time is shown, wherein, based on a plurality of single shot related post-data, a preset acquisition parameter and a plurality of first post-suppression data, determining the first sliding time corresponding to a preset distance includes:

[0121] S301 : Acquire a first threshold value of a plurality of first suppressed data based on a plurality of noise-correlated data and preset acquisition parameters.

[0122] During the experiment, when the interference of the rear shot is reduced to a level lower than that of the ambient noise, it can be considered that it will not affect the front shot. Therefore, based on multiple noise-related rear data and preset acquisition parameters, the energy values ​​of multiple ambient noise data are determined, and used as the sliding time to determine at which the harmonic interference of the rear shot is reduced to less than the ambient noise interference.

[0123] S302, based on the data except the noise-correlated data in the single-shot correlated data, determine the first root mean square energy values ​​of the plurality of first suppressed data to obtain corresponding curves of the first root mean square energy values ​​and the sliding time corresponding to the plurality of test points.

[0124] After the first compression data H' k The first RMS energy value of harmonic interference is counted, and the time window range is selected as [T obj -2s, T obj ], offset [2Δx, R harm ],

[0125]

[0126] Where nx represents the track number corresponding to the minimum offset in the test data; T obj Indicates the reflection time of the deepest target layer in the work area.

[0127] Through the above formula, the time-energy corresponding curve after harmonic suppression at each test point is obtained.

[0128] S303, obtaining intervals on each corresponding curve where the first root mean square energy value is less than a first threshold, and determining the minimum value of the sliding time in each interval as the first preset sliding time at each test point;

[0129] After obtaining the time-energy corresponding curve of each test point after harmonic suppression, the interval in which each time-energy corresponding curve is less than the first threshold value is determined according to the first threshold value, the interval is the interval in which the energy value is lower than the energy threshold value of the ambient noise, and the sliding time in the interval is the sliding time in which the influence on the pre-shot is small.

[0130] Then, the minimum sliding time in the interval corresponding to each test point is selected, wherein the minimum unit is s, and then the first preset sliding time of each test point is obtained.

[0131] S304, the maximum value in the plurality of first preset sliding times is determined as the first sliding time.

[0132] By selecting the maximum first preset interval in each test point, the finally determined first sliding time meets all test points.

[0133] In an embodiment, referring to Figure 8 , a flowchart of a step of determining the first threshold value is shown, a plurality of first threshold values of a plurality of second harmonic interferences are obtained based on a plurality of single-shot correlated data and a plurality of preset acquisition parameters, including:

[0134] S3011, based on a plurality of preset acquisition parameters, a range of energy statistical time windows corresponding to each background noise energy of a plurality of single-shot correlated data is determined, and an offset distance of each energy statistical time window range is determined.

[0135] In this embodiment, the energy statistical time window range can be [0s, 2s], and the offset distance of the energy statistical time window range can be [L Array -R background , L Array ], wherein L Array is a preset distance, and R background represents a background noise energy statistical distance range.

[0136] S3012, according to the offset distance corresponding to each energy statistical time window range, noise data in which each single-shot correlated data is located in the respective energy statistical time window is determined, thereby determining the background noise energy value in the plurality of energy statistical time windows;

[0137] The energy statistical time window is a selection range of data selected on the single-shot correlated data, data in the plurality of energy statistical time windows is selected on the single-shot correlated data, and it is ensured that there is no first arrival information in the statistical time window, and then the background noise energy value in each energy statistical time window is calculated according to the following formula,

[0138]

[0139] L Array = ceil(LArray ), ceil represents the rounding up function.

[0140] S3013: Determine an energy average value according to the multiple background noise energy values, and determine the energy average value as a first threshold.

[0141] In some embodiments, reference Figure 9 , a flowchart of the steps for determining the second sliding time, wherein the acquisition method further comprises: for each single shot related post data, performing the following steps:

[0142] S401, based on the single shot correlation data, determining a minimum synchronization distance outside a preset distance from a test point corresponding to the single shot correlation data;

[0143] Determining the minimum synchronization distance may include the following steps:

[0144] First, obtain the first arrival time of the single shot correlation data S' collected at both ends of the test line;

[0145] Determine the reflection time T from the deepest target layer obj The offset distance corresponding to the equal first arrival time and

[0146] Determine the offset distance according to the following formula Calculate the minimum synchronous distance D of the earthquake source synch :

[0147] D synch =ceil(OFF obj +L Array )

[0148] S402, performing a dynamic sliding test simulation based on the environmental noise correlation data to obtain the second harmonic interference;

[0149] Before obtaining the second harmonic interference, first obtain the single-shot correlation data S' on both sides of the test point and re-sort them according to the following formula:

[0150]

[0151] Where S' is the rearranged data; the data in the first formula is defined as the trace number increasing with the increase of the offset; the data in the second formula is defined as the trace number decreasing with the increase of the offset.

[0152] The re-sorted single shot correlation data S" is spliced ​​into bilateral arrangement received data.

[0153]

[0154] Then, according to the bilateral arrangement of received data, the source spacing is within the preset distance to the minimum synchronization distance, with a value interval of 1km.

[0155] The focal distance is DX(l)∈[L Array +1km,L Array +R harm ]

[0156] The sliding time is ST(k)∈[1s,ST inArray ]

[0157] Perform displacement and time shift to obtain the second harmonic interference data SH k,l .

[0158] SH k,l =S”' k,l (i,j)i=nt,nt+1,…,nt+N1-M j=nx,nx+1,…,nx+N trc -1

[0159] Where nt = N1 - ST(k) / Δt; nx = N trc -DX(l) / Δx+1.

[0160] S403, performing harmonic suppression on the second harmonic interference data according to the force signal data to obtain second suppressed data;

[0161] Using force signal data to analyze the second harmonic interference data SH k,l Perform harmonic suppression, and after the second suppression, the data SH' k,l The second root mean square energy value of harmonic interference is calculated according to the above formula. The statistical time window range can be [T obj -2s, T obj ], the offset can be [L Array -R harm , L Array ]:

[0162]

[0163] S404, determining second sliding times corresponding to different preset source spacings within a range from the preset distance to the minimum synchronization distance based on the single shot correlation data, acquisition parameters, the minimum synchronization distance, and the second suppressed data.

[0164] The minimum value of the sliding time ST(k) corresponding to the second root mean square energy value E4(k) being less than the threshold E2 is determined as the sliding time corresponding to avoiding the back-shot harmonic interference under the case of the source spacing DX(l), thereby obtaining the second sliding time corresponding to different preset source spacings within the preset distance to the minimum synchronization distance. By eliminating the harmonic interference in the seismic experiment, a more accurate second sliding time is obtained.

[0165] In some embodiments, reference Figure 10 , showing a flowchart of the steps for confirming the harmonic interference radius, the acquisition method further includes:

[0166] S501, determining, based on each shot-correlated data, a second root mean square energy value of the shot-correlated data within a preset time range, and a noise root mean square energy value within the preset time range;

[0167] When calculating the second sliding time, by taking the test point with the largest harmonic interference radius among the three test points, the sliding time of this test point can be compatible with other test points, without calculating all test points, thereby reducing the amount of calculation.

[0168] S502, determining the harmonic interference radius of each single shot correlation data based on the second root mean square energy value and the root mean square average energy value;

[0169] According to the previously obtained single shot correlation data S' and the environmental noise correlation data S in the single shot correlation data environment , calculate the time range of each track of the single shot correlation data S' of each test point [-(T b -T s ),0] within the root mean square energy value E1:

[0170]

[0171] Then calculate the record S according to the formula environment All channels are in the time range [-(T b -T s ),0] within the RMS energy average value E environment :

[0172]

[0173] Calculate the energy ratio R E (j) = E1(j) / E environment , energy ratio R E The offset distance corresponding to (j)≤1 is taken as the harmonic interference radius R harm .

[0174] S503 , performing a dynamic sliding test simulation based on the single-shot correlation data corresponding to the largest harmonic interference radius among the single-shot correlation data.

[0175] The second preset sliding time is determined by taking the single-shot correlation data corresponding to the largest harmonic interference radius among the harmonic interference radii. Only the single-shot correlation data corresponding to the largest harmonic interference radius is calculated, which can be backward compatible with other data. There is no need to perform correlation calculations on the data of all test points, which effectively reduces the computational complexity of the entire method.

[0176] In some embodiments, reference Figure 11 , showing a flowchart of the steps for determining the second preset sliding time, the acquisition method further includes:

[0177] S601, respectively determining a second preset sliding time corresponding to each adjacent shot interference type among multiple other adjacent shot interference types; wherein the multiple adjacent shot interference types include at least a rear shot first arrival wave interference, a front shot surface wave interference, and a front shot direct arrival wave interference;

[0178] Interference types include rear gun harmonic interference, rear gun first arrival wave interference, front gun surface wave interference and front gun direct wave interference, and various situations are analyzed in turn.

[0179] Among them, based on the interference type being post-shot harmonic interference:

[0180] Obtain the single shot correlation data S' on both sides of the test point and reorder them according to the following formula:

[0181]

[0182] Where S' is the rearranged data; the data in the first formula is defined as the trace number increasing with the increase of the offset; the data in the second formula is defined as the trace number decreasing with the increase of the offset.

[0183] The re-sorted single shot correlation data S" is spliced ​​into bilateral arrangement received data.

[0184]

[0185] Then, according to the bilateral arrangement of received data, the source spacing is within the preset distance to the minimum synchronization distance, with a value interval of 1km.

[0186] The focal distance is DX(l)∈[L Array +1km,L Array +R harm ]

[0187] The sliding time is ST(k)∈[1s,ST inArray ]

[0188] Displacement and time shift are performed to obtain second harmonic interference data SH k,l .

[0189] SH k,l = S" k,l (i,j)i=nt,nt+1,…,nt+N1-M j=nx,nx+1,…,nx+N trc -1

[0190] wherein nt=N1-ST(k) / Δt; nx=N trc -DX(l) / Δx+1.

[0191] The force signal is used to the second harmonic interference data SH k,l Harmonic suppression is performed on the second suppressed data SH' k,l The second root mean square energy value of the harmonic interference is calculated on the second suppressed data SH' according to the following formula, and the time window range can be [T obj -2s, T obj ], and the offset distance can be [L Array -R harm , L Array ]. The minimum value of the sliding time ST(k) corresponding to the second root mean square energy value E4(k) less than the threshold value E2 is determined as the sliding time corresponding to the source distance DX(l) to avoid the post-shot harmonic interference, so as to obtain the second preset sliding time corresponding to different preset source distances within the preset distance to the minimum synchronization distance:

[0192]

[0193] When the interference type is post-shot first arrival wave interference:

[0194] The offset distance DX(l)-L Array corresponding to the first arrival time FB1(l) and FB2(l) is determined, wherein DX(l)∈[L Array +1km, D synch -1km].

[0195] Given the threshold T tol , the first arrival time FB(l)=min(FB1(l),FB2(l)) is determined, and the second preset sliding time ST2(l) corresponding to the source distance DX(l) to avoid post-shot first arrival wave interference is calculated according to the following formula, wherein T tol represents the maximum time value allowed for post-shot first arrival wave interference into the pre-shot data range:

[0196] ST2(l)=ceil(T tol -FB(l))

[0197] When the interference type is front gun surface wave interference:

[0198] The surface wave interference radius of each test point is determined based on the single-shot correlation data. The single-shot correlation data with a larger surface wave interference radius is used for dynamic sliding test simulation to obtain the rearranged data S” and the bilaterally arranged received data S”’. The surface wave velocity V is obtained on S”. ground And the first arrival time FB.

[0199] The simulated records are divided into the source spacing DX(l)∈[L Array +1km,D synch -1km] and the sliding time ST(k)∈[1s,ST inArray ] to perform displacement and time shift to obtain surface wave interference data SH k,l :

[0200] SH k,l =S”' k,l (i,j)i=nt,nt+1,…,nt+N1-M j=nx,nx+1,…,nx+N trc -1.

[0201] The ratio between the energy value of the interference in the single-shot correlation data of the rear shot and the energy value of the front shot surface wave is calculated as follows: inter and OFF inter It represents the time and offset of the intersection of the first arrival wave and the surface wave when the sliding time is ST(k), and nWin represents the number of sample points in the time window radius:

[0202]

[0203] Among them, D obj =ceil(V ground ·(T obj +ST(k))); nWin=0.2 / Δt; nt1=N1+(j·Δx / V ground ) / Δt;nt2=N1+(j·Δx / V ground -ST(k)) / Δt.

[0204] Determine the evaluation threshold R according to the actual situation tol , with Ratio(k,l)≥R tol The minimum value of the corresponding sliding time ST(k) is determined as the second preset sliding time ST3(l) corresponding to avoiding the interference of the front shot surface wave under the condition of the source spacing DX(l).

[0205] When the interference type is the front gun direct wave interference:

[0206] Analogously to the above test, determine the single-shot correlation data of the test point with the direct wave interference radius, obtain the rearranged data S" and the bilaterally arranged received data S"', and calculate the ratio between the energy value of the interfered energy in the single-shot correlation data of the rear shot and the energy value of the direct wave of the front shot according to the following formula:

[0207]

[0208] Where nWin represents the number of sample points of the time window radius, V direct represents the apparent velocity of the direct wave, nWin=0.2 / Δt;nt1=N1+(j·Δx / V direct ) / Δt;nt2=N1+(j·Δx / V direct -ST(k)) / Δt; D obj =ceil(V direct ·T obj ).

[0209] Determine the evaluation threshold R according to the actual situation tol , with Ratio(k,l)≥R tol The minimum value of the corresponding sliding time ST(k) is determined to be the second preset sliding time ST4(l) corresponding to avoiding interference of the direct wave of the preceding shot under the condition of the source spacing DX(l).

[0210] S602: Determine the second sliding time with the largest value among the plurality of second preset sliding times as the second sliding time.

[0211] According to different interferences, multiple expected corresponding second preset sliding times ST1(l), ST2(l), ST3(l) and ST4(l) are obtained, and the one with the largest value is determined as the second sliding time, thereby solving the above-mentioned different interferences and improving the applicability of the entire method.

[0212] In some embodiments, reference Figure 12 , showing a flow chart of steps for determining a time-distance regular curve, the method further includes:

[0213] S701, calibrating the sliding time corresponding to the minimum synchronization distance to a preset value;

[0214] Generally speaking, outside the minimum synchronization distance, the interference between earthquake sources is low and the corresponding sliding time can be calibrated to 0.

[0215] S702 : Determine a time-distance rule curve according to a preset distance, a minimum synchronization distance, a first sliding time, a second sliding time, and a preset value.

[0216] After determining the sliding time within the preset distance, from the preset distance to the minimum synchronization distance, and outside the minimum synchronization distance, a corresponding curve between distance and sliding time is constructed, thereby obtaining a time-distance regular curve, making the corresponding relationship between the focal distance and sliding time more intuitive.

[0217] In a specific embodiment, referring to Figure 1 The surface conditions of the application area mainly include saline-alkali land, Gobi and desert. According to the surface conditions of the work area and combined with the detailed survey results, the location of the test line is determined. There are three test points, which are located in the saline-alkali land, Gobi area and desert area of ​​the experimental work area, and are located at the two ends and the middle of the test line respectively.

[0218] In one specific embodiment, a single-shot acquisition source is selected, with a sweep frequency of 1.5-96 Hz, a sweep length of 18 seconds, a drive amplitude of 65%, and a start and end ramp of 0.48 seconds. A single SG5 detector can be used for reception, with a sampling interval of 2 ms, a pre-correlation data length of 26 seconds, and a post-correlation data length of 8 seconds. Furthermore, the observation system parameters include a trace spacing of 25 meters, a number of received channels of 720, and a full array reception mode.

[0219] Single-shot single-excitation experiments were carried out at the three test points in turn to obtain the single-shot correlation pre-records of the three test points and the force signal data of the three seismic sources. The environmental noise data on the entire test line was also recorded. Then, preset processing, i.e., correlation processing, was performed to obtain the single-shot correlation post-data of the three test points.

[0220] The root mean square (RMS) noise energy at the noise-correlated data points within the single-shot correlation data was calculated. The preset distance was 8 km, determined based on the production length of the work area. To mitigate first-arrival interference, the background noise energy was statistically analyzed at a distance of 3 km. The statistical window for background noise was [0s, 2s] in time and [5km, 8km] in offset. The average value of the background noise energy at these locations, 0.01, was used as the first threshold.

[0221] Reference Figure 4 Using single-shot correlation data from three test points, we extracted the first harmonic interference within the pre-interference shot range within the sliding time range of [8s, 16s]. This harmonic interference was suppressed using the force signal file to obtain the first suppressed data. Based on the physical parameters of the test area, the reflection time of the deepest target layer in the area is 4s, and the harmonic interference noise should avoid the mechanical noise of the two-channel source near the offset. Therefore, referring to 11, the statistical time window for harmonic interference energy was determined as: [2s, 4s] in time direction; [0.075km, 6.575km] in offset direction.

[0222] Reference Figure 13, the harmonic interference energy is counted on the data after the first suppression, and the first threshold value 0.01 is determined based on the average value of the background noise energy value at five locations, referring to Figure 14 When the sliding time is greater than or equal to 12 seconds, the harmonic interference energy values ​​in the three types of surface data are all less than the first threshold. Therefore, the first sliding time within the arrangement range is determined to be 12 seconds.

[0223] The first arrival times of the single-shot correlation data at the three test points were obtained respectively, and the offset distance corresponding to the first arrival time equal to the reflection time of the deepest target layer of 4s was read. The corresponding offset distance of the test point in the saline-alkali land was 10km, and the corresponding offset distance of the test point in the desert area was 9.9km. Therefore, the minimum synchronous distance between the sources is 10km+8km, that is, 18km.

[0224] Statistical analysis of the three excitation points to collect and record the harmonic interference radius, refer to Figure 15 The harmonic interference radius in the saline-alkali area is 6.5km, the harmonic interference radius in the Gobi area is 6.0km, and the harmonic interference radius in the desert area is 6.5km. Therefore, the maximum harmonic interference radius of 6.5km is determined as the harmonic interference radius, and the single-shot correlation data of the test point in the desert area is determined as the data for calculating the second sliding time. Therefore, a dynamic sliding test simulation is performed on the single-shot correlation data of the test point in the desert area to obtain the rearranged data and the bilaterally arranged received data, and the second suppression data of this test point is obtained.

[0225] Based on the single-shot correlation data from the test point in the desert, as well as the realigned data and bilaterally aligned received data, the second preset sliding time for four interference scenarios with preset distances between 8km and 18km was calculated. The case of a 9km source separation was used as an example:

[0226] When the interference type is post-shot harmonic interference, refer to Figure 16 , the harmonic energy is counted on the data after the second suppression, and the harmonic interference energy statistical window is: time direction [2s, 4s]; offset direction: [1.5km, 8km] refer to Figure 17 Taking the background noise energy value as the first threshold, determining the second preset sliding time to be 7s;

[0227] When the interference type is the first arrival wave interference of the subsequent shot, refer to Figure 16 The lower left inclined dashed line shows the first arrival time at an offset of 1 km, i.e., a focal separation of 9 km. This is the minimum first arrival time within the correlation data of a single shot before the first arrival wave of the subsequent shot interferes. Taking the correlation data length of 8 s as the threshold, the sliding time for a focal separation of 9 km is calculated as ceil(8s-0.65s) = 8s.

[0228] Reference Figure 18 and Figure 19, based on the interference type of the front shot surface wave interference, the surface wave apparent velocity of the data is obtained, and the inclined rectangular time window is determined by the surface wave apparent velocity slope, the deepest target layer reflection time and the first arrival time of the rear shot. Figure 20 , determine the energy ratio of the back-shot data to the front-shot surface wave under the condition of a sliding time of 10s, calculate the average value of the energy ratio of all traces as 2.66, and set the evaluation threshold as 1. If the average energy ratio is greater than the threshold, it is considered that the direct wave of the front shot is lower than the correlation data of the single back-shot. Therefore, when the focal distance is 9km, a sliding time of 10s is used as the second preset sliding time to avoid interference with the front-shot surface wave.

[0229] Reference Figure 21 and Figure 22 When the interference type is the direct wave interference from the front shot, the apparent wave velocity on the data is obtained, and the inclined rectangular time window is determined by the slope of the direct wave apparent velocity and the reflection time of the deepest target layer. Figure 23 The energy ratio of the interfered data from the subsequent shot to the direct wave from the preceding shot was determined for a 5-second sliding time. After removing the strongly interfering data, the remaining energy ratios were averaged, yielding an average value of 439. The evaluation threshold was set at 100. If the energy ratio exceeded the threshold, it was assumed that the direct wave from the preceding shot had little impact on the subsequent shot data. Therefore, a 5-second sliding time was used as the second preset sliding time to avoid interference from the direct wave from the preceding shot when the focal distance was 9 km.

[0230] In summary, when the focal distance is 9 km, the second sliding time can be 10 s. Given the focal distance range [8 km, 18 km], as shown in the following table:

[0231]

[0232]

[0233] Determine the second sliding time corresponding to each group of source spacing in the above manner. Figure 24 Based on the distances between the various seismic sources, a dynamic sliding scanning time-distance rule curve is derived. When the source spacing is less than the work area length, that is, between 1km and 8km, the sliding time is always the same as the first sliding time to avoid harmonic interference. When the source spacing is outside the work area length but within the minimum synchronization distance, that is, between 9km and 19km, the sliding time gradually changes as the source spacing increases to ensure that any interference between the two sources does not affect each other. When the source spacing exceeds the minimum synchronization distance, that is, after 18km, the interference wave of the source will not affect the other source beyond the minimum synchronization distance, so the two sources can be excited simultaneously, and the sliding time is zero.

[0234] Example 2

[0235] A second aspect of an embodiment of the present application provides a sliding time acquisition system, including:

[0236] An acquisition module is used to acquire a plurality of single shot correlation pre-data and a plurality of force signal data generated when a seismic experiment is conducted at a plurality of test points on a test line, and to acquire environmental noise data on the test line;

[0237] The acquisition module includes a controllable vibrator for exciting vibrations, a detector for acquiring data, etc.

[0238] a preset processing module for performing preset processing on the plurality of single-shot pre-correlation data and the environmental noise data to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes noise post-correlation data;

[0239] The suppression module is used to determine the first harmonic interference data corresponding to different sliding times of multiple single-shot related pre-data within a preset time range based on a preset distance and multiple single-shot related post-data; and to perform harmonic suppression on the first harmonic interference according to multiple force signal data to obtain multiple first suppressed data; wherein the preset distance is the production arrangement length of the test work area.

[0240] A determination module is configured to determine, based on the plurality of single-shot correlation data, preset acquisition parameters, and the plurality of first and second suppression data, a first sliding time within the preset distance and a second sliding time corresponding to different preset source spacings from the preset distance to the minimum synchronization distance; and determine the time-distance rule curve according to the preset distance, the minimum synchronization distance, the first sliding time, the second sliding time, and the preset value.

[0241] In some embodiments, the acquisition module is further configured to perform the following steps:

[0242] Determine the test line location and the number of test points based on the surface conditions of the work area, and determine the test point locations based on the test line location;

[0243] Determine the excitation parameters and scanning signal parameters, and control multiple vibrators to conduct a single-shot seismic experiment at the test point;

[0244] Based on the preset acquisition parameters, the single shot related pre-data and force signal data of each of the multiple test points are acquired to obtain multiple single shot related pre-data and multiple force signal data.

[0245] In some embodiments, the determining module is further configured to perform the following steps:

[0246] Based on the preset distance and multiple single-shot correlation data, a preset time range for extracting the first harmonic interference is determined;

[0247] Based on the correlated data of multiple single shots, the first harmonic interference corresponding to different sliding times within the preset time range is obtained.

[0248] Based on the plurality of noise-correlated data and the preset acquisition parameters, obtaining a first threshold value of the plurality of first suppressed data;

[0249] Determining first root mean square energy values ​​of a plurality of first suppressed data based on data other than noise-correlated data in the single-shot correlated data, so as to obtain corresponding curves of the first root mean square energy values ​​and the sliding time corresponding to each of the plurality of test points;

[0250] Obtaining intervals on each corresponding curve where the first root mean square energy value is less than the first threshold, and determining the minimum value of the sliding time in each interval as the first preset sliding time at each test point;

[0251] A maximum value among the plurality of first preset sliding times is determined as the first sliding time.

[0252] Based on a plurality of preset acquisition parameters, determining an energy statistical time window range of each background noise energy corresponding to the data after correlation of the plurality of single shots, and an offset distance of each energy statistical time window range;

[0253] According to the offset distances corresponding to the multiple energy statistical time windows, the noise data of the correlated data of each single shot is determined to be within the respective energy statistical time windows, thereby determining the background noise energy values ​​within the multiple energy statistical time windows;

[0254] An energy average is determined according to the multiple background noise energy values, and the energy average is determined as the first threshold.

[0255] In some embodiments, the acquisition system further includes a second sliding time acquisition module configured to perform the following steps:

[0256] Based on a plurality of preset acquisition parameters, determining an energy statistical time window range of each background noise energy corresponding to the data after correlation of the plurality of single shots, and an offset distance of each energy statistical time window range;

[0257] According to the offset distances corresponding to the multiple energy statistical time windows, the noise data of the correlated data of each single shot is determined to be within the respective energy statistical time windows, thereby determining the background noise energy values ​​within the multiple energy statistical time windows;

[0258] An energy average is determined according to the multiple background noise energy values, and the energy average is determined as the first threshold.

[0259] The second sliding time acquisition module performs the following steps for each single shot related data:

[0260] Based on the correlated data of each single shot, determining the minimum synchronization distance outside the preset distance from the test point corresponding to the correlated data of the single shot;

[0261] A dynamic sliding test simulation is conducted based on the environmental noise correlation data to obtain the second harmonic interference;

[0262] Performing harmonic suppression on the second harmonic interference data according to the force signal data to obtain second suppressed data;

[0263] According to the single shot correlation data, acquisition parameters, minimum synchronization distance and second suppression data, second sliding times corresponding to different preset source spacings within the preset distance to the minimum synchronization distance are determined.

[0264] Determining, based on the single shot correlation data, second root mean square energy values ​​of a plurality of test points within a preset time range, and noise root mean square energy values ​​of the plurality of test points within the preset time range;

[0265] Determine the harmonic interference radius of each test point according to the second root mean square energy value and the root mean square average energy value;

[0266] Dynamic sliding test simulation is performed based on the single-shot correlation data corresponding to the largest harmonic interference radius among multiple harmonic interference radii.

[0267] The second sliding time acquisition module performs the following steps:

[0268] respectively determining second preset sliding times corresponding to the second suppressed data under various interference types;

[0269] Among them, the multiple adjacent gun interference types include at least the rear gun harmonic interference, the rear gun first arrival wave interference, the front gun surface wave interference and the front gun direct wave interference;

[0270] The largest value among the plurality of second preset sliding times is used as the second sliding time.

[0271] In some embodiments, the determining module is further configured to perform the following steps:

[0272] Calibrate the sliding time corresponding to the minimum synchronization distance to the preset value;

[0273] A time-distance rule curve is determined according to the preset distance, the minimum synchronization distance, the first sliding time, the second sliding time and the preset value.

[0274] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0275] The multiple embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts between the multiple embodiments can be referenced to each other.

[0276] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, devices, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0277] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0278] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0279] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0280] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0281] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0282] The above is a detailed introduction to the sliding time acquisition method and system for controllable source aliasing acquisition provided by this application. This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method of this application and its core idea; at the same time, for general technical personnel in this field, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on this application.

Claims

1. A sliding time acquisition method, characterized in that: The acquisition method includes: Acquiring a plurality of single-shot correlation pre-data and a plurality of force signal data generated when conducting seismic experiments at a plurality of test points on a test line, and acquiring environmental noise data on the test line; The plurality of single-shot pre-correlation data and the environmental noise data are processed in a preset manner to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes environmental noise post-correlation data; Determining, based on a preset distance and a plurality of the single-shot correlation data, first harmonic interference data corresponding to different sliding times within a preset time range for a plurality of the single-shot correlation data before the single-shot correlation; and performing harmonic suppression on the first harmonic interference according to the plurality of the force signal data to obtain a plurality of first suppressed data; wherein the preset distance is the production arrangement length of the test work area; A first sliding time within the preset distance is determined based on the plurality of single-shot related post-data, preset acquisition parameters and the plurality of first post-suppression data.

2. The acquisition method according to claim 1, characterized in that Acquire multiple single-shot correlation data and multiple force signal data generated when conducting seismic experiments at multiple test points on the test line, including: Determine the test line position and the number of test points according to the surface conditions of the work area, and determine the test point positions according to the test line position; Determine excitation parameters and scanning signal parameters, and control multiple vibrators to perform a single-unit single-shot seismic experiment at the test point; Based on the preset acquisition parameters, the single shot related pre-data and the force signal data of each of the multiple test points are acquired to obtain the multiple single shot related pre-data and the multiple force signal data.

3. The acquisition method according to claim 1, characterized in that Determining first harmonic interference data corresponding to different sliding times within a preset time range of the plurality of single-shot pre-correlation data based on a preset distance and the plurality of single-shot post-correlation data includes: Determining a preset time range for extracting the first harmonic interference based on a preset distance and the plurality of single-shot correlation data; Based on the plurality of single-shot correlated data, first harmonic interference corresponding to different sliding times is obtained within the preset time range.

4. The acquisition method according to claim 1, characterized in that Determining a first sliding time corresponding to the preset distance based on the plurality of single-shot related post-data, preset acquisition parameters, and the plurality of first post-suppression data includes: Based on the plurality of noise-correlated data and preset acquisition parameters, obtaining first thresholds of the plurality of first suppressed data; Determining first root mean square energy values ​​of a plurality of first suppressed data based on data other than the noise-correlated data in the single-shot correlated data, so as to obtain corresponding curves of the first root mean square energy values ​​and sliding time corresponding to respective test points; Obtaining intervals on each of the corresponding curves where the first root mean square energy value is less than the first threshold, and determining the minimum value of the sliding time in each of the intervals as the first preset sliding time at each test point; A maximum value among a plurality of first preset sliding times is determined as the first sliding time.

5. The acquisition method according to claim 4, characterized in that: The obtaining of a plurality of first thresholds of the first harmonic interference based on the plurality of single-shot correlation data and preset acquisition parameters includes: Based on the plurality of preset acquisition parameters, determining an energy statistical time window range of each background noise energy corresponding to the plurality of single shot correlation data, and an offset distance of each energy statistical time window range; Determining the noise data of each of the single shot correlation data within the respective energy statistical time windows according to the offset distances corresponding to the respective energy statistical time windows, thereby determining the background noise energy values ​​within the plurality of energy statistical time windows; An energy average is determined according to the multiple background noise energy values, and the energy average is determined as the first threshold.

6. The acquisition method according to claim 1, characterized in that: The acquisition method further includes: For each shot-related data, perform the following steps: Determine the minimum synchronization distance outside the preset distance based on the first arrival time of the single shot correlation data, the preset distance, and the preset maximum reflection time of the target layer; Perform a dynamic sliding test simulation based on the single shot correlation data to obtain the second harmonic interference; performing harmonic suppression on the second harmonic interference data according to the force signal data to obtain second suppressed data; According to the single shot correlation data, the acquisition parameters, the minimum synchronization distance and the second suppressed data, a second preset sliding time corresponding to different preset source spacings within the preset distance to the minimum synchronization distance is determined.

7. The acquisition method according to claim 6, characterized in that: The acquisition method further includes: Determine, based on each shot-correlated data, a second root mean square energy value of the shot-correlated data within a preset time range, and a noise root mean square energy value within the preset time range; determining a harmonic interference radius of each single shot correlation data according to the second root mean square energy value and the root mean square average energy value; Dynamic sliding test simulation is performed based on the single-shot correlation data corresponding to the largest harmonic interference radius among the single-shot correlation data.

8. The acquisition method according to claim 6, characterized in that: The method further comprises: Determining a second preset sliding time corresponding to each adjacent gun interference type among a plurality of other adjacent gun interference types; wherein the plurality of other adjacent gun interference types at least include a rear gun first arrival wave interference, a front gun surface wave interference, and a front gun direct arrival wave interference; The one with the largest value among the plurality of second preset sliding times is determined as the second sliding time.

9. The acquisition method according to claim 6, characterized in that: The method further comprises: Calibrate the sliding time corresponding to the minimum synchronization distance to a preset value; A time interval rule curve is determined according to the preset distance, the minimum synchronization distance, the first sliding time, the second sliding time and the preset value, and the second preset sliding time has the largest index value of the second sliding time.

10. A time-distance regular curve acquisition system, characterized in that: include: an acquisition module, configured to acquire a plurality of single-shot correlation pre-data and a plurality of force signal data generated when a seismic experiment is performed on a plurality of test points on a test line, and to acquire environmental noise data on the test line; a preset processing module, configured to perform preset processing on the plurality of single-shot pre-correlation data and the environmental noise data to obtain single-shot post-correlation data corresponding to each of the plurality of single-shot pre-correlation data; wherein the single-shot post-correlation data includes noise post-correlation data; a suppression module, configured to determine, based on a preset distance and the plurality of single-shot correlation data, first harmonic interference data corresponding to different sliding times within a preset time range for the plurality of single-shot correlation data before the single-shot correlation data; and perform harmonic suppression on the first and second harmonic interferences according to the plurality of force signal data to obtain a plurality of first and second suppressed data; a determination module, configured to determine a first sliding time within the preset distance based on the plurality of single shot related post-data, preset acquisition parameters, and the plurality of first and second post-suppression data; It is also used to determine the time-distance rule curve according to the second sliding time corresponding to different preset source spacings within the preset distance to the minimum synchronization distance, according to the preset distance, minimum synchronization distance, the first sliding time, the second sliding time and the preset value limit, wherein the preset value represents the sliding time corresponding to outside the minimum synchronization distance.

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