A method, apparatus, electronic device, and storage medium for enhancing seismic record signals.

Abstract

This invention provides a method, device, electronic device, and storage medium for enhancing seismic record signals, relating to the technical field of geophysical exploration. The method includes sequentially stitching multiple seismic records from various shots into a single-shot stitched seismic record; determining the time shift between the stitched seismic records of each shot based on cross-correlation analysis, obtaining the relative time shift of each shot relative to the first shot, and generating an aligned single-shot stitched seismic record; superimposing and normalizing the aligned single-shot stitched seismic records; and extracting the dispersion energy map of the superimposed multi-shot stitched seismic records using the phase-shift method. This invention solves the problem of low signal-to-noise ratio caused by the inability to accurately superimpose multi-shot seismic records without a timing device, achieving the technical effect of enhancing the signal-to-noise ratio of surface wave signals and dispersion energy maps, and improving the reliability of subsurface structure imaging.

Description

Technical Field

[0001] This invention relates to the field of geophysical exploration technology, and in particular to a method, apparatus, electronic device, and storage medium for enhancing seismic record signals. Background Technology

[0002] Active source surface wave exploration is a widely used technique for imaging subsurface structures. It generates seismic waves by artificially exciting a seismic source and utilizes the dispersion characteristics of surface waves in the medium to invert subsurface velocity structures. Surface wave signals are easily and strongly affected by complex geological conditions during propagation, resulting in single-shot records from distant detectors (far from the source) acquiring only weak, effective signals. Multi-shot stacking techniques, by superimposing multiple seismic ensemble records from different shots, can suppress random noise and enhance weak signals caused by strong attenuation, thus obtaining more reliable surface wave characteristics. In traditional active source surface wave exploration, the stacking process relies on precise time synchronization. In scenarios without time synchronization devices, such as low-cost portable equipment or deployment in harsh environments, accurate source excitation times cannot be obtained. If the start times of the seismic records from different shots are inconsistent, direct stacking of these records can introduce phase errors or even erroneous signals, thereby reducing the signal-to-noise ratio of the surface wave signal or generating false signals.

[0003] However, the existing technology has the following problems: without a timing device, it is impossible to accurately superimpose multi-shot seismic records, resulting in a low signal-to-noise ratio. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a method, apparatus, electronic device and storage medium for enhancing seismic record signals, so as to alleviate the technical problem that the accurate superposition of multi-shot seismic records cannot be achieved without a timing device, resulting in a low signal-to-noise ratio.

[0005] In a first aspect, embodiments of this application provide a method for enhancing seismic record signals, the method comprising: Acquire multi-shot, multi-channel seismic records from the seismic station array deployed at the test site, and stitch the multi-channel seismic records from each shot into a single column of data to obtain the stitched seismic record of a single shot. Based on cross-correlation analysis, the time shift between the mosaic seismic records of each shot is determined. Taking the first mosaic seismic record in the multi-shot multi-channel seismic record as the reference signal, cross-correlation analysis is performed on each second mosaic seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Based on the relative time shift, the first mosaic seismic record in the single-shot mosaic seismic record is shifted in the time domain to align the columns corresponding to the second mosaic seismic records in the single-shot mosaic seismic record with the columns corresponding to the first shot mosaic seismic record in the time domain, generating the aligned single-shot mosaic seismic record. The aligned single-shot mosaic seismic records are superimposed to generate multi-shot mosaic seismic records. For multi-shot seismic records, the corresponding channel column data of the shot is restored from the mosaic seismic records to generate multi-column data. Each column of the multi-column data is then normalized to generate multi-shot mosaic seismic records. Dispersion energy maps of multi-shot seismic records after stacking were extracted using the phase-shift method.

[0006] In one implementation of the first aspect, the process of determining the time shift between the stitched seismic records of each shot based on cross-correlation analysis is as follows: The stitched seismic records of each shot are integrated using a cross-correlation function, and the integrated stitched seismic records are output. The maximum and minimum values ​​for each shot in the integrated mosaic seismic record are searched to determine the time shift between the mosaic seismic records for each shot.

[0007] Furthermore, the cross-correlation function is expressed as: , in, Represents the time delay variable. Indicates the first The spliced ​​seismic records of the cannons express .

[0008] In one implementation of the first aspect, the translation process includes: shifting the stitched seismic records of each shot along the time axis by the relative time shift of each shot relative to the first shot by a sampling point; when the relative time shift is positive, it indicates that there is a delay in each shot relative to the first shot, and the stitched seismic records of each shot need to be shifted in the direction of decreasing time; when the relative time shift is negative, it indicates that each shot is ahead of the first shot, and the stitched seismic records of each shot need to be shifted in the direction of increasing time.

[0009] In one implementation of the first aspect, the stacking of aligned single-shot seismic records is determined based on the following formula: , in, The number of shots superimposed on the earthquake records. This is a composite earthquake record after being overlaid. This represents the relative time shift of each gun relative to the first gun.

[0010] In one implementation of the first aspect, the normalization process includes: for each trace or column of spliced ​​seismic records, finding the maximum amplitude of the corresponding trace or the maximum absolute value of all sampling points in the corresponding column, and then dividing the value of each sampling point in the corresponding column by the corresponding maximum value, so that the maximum amplitude value of each trace is normalized to 1.

[0011] Secondly, embodiments of this application provide a seismic record enhancement signal device, the device comprising: The stitched seismic record generation module is used to acquire multi-shot multichannel seismic records from the seismic station array deployed at the test site, and stitch the multichannel seismic records of each shot into a column of data in sequence to obtain the stitched seismic record of a single shot. The seismic record time-shift module is used to determine the time shift between the seismic records of each shot based on cross-correlation analysis. Taking the first seismic record in the multi-shot multi-channel seismic record as the reference signal, cross-correlation analysis is performed on each second seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Based on the relative time shift, the first seismic record in the single-shot seismic record is shifted in the time domain to align the columns corresponding to the second seismic records in the single-shot seismic record with the columns corresponding to the first seismic record in the time domain, generating the aligned single-shot seismic record. The stitched seismic record overlay module is used to overlay the aligned stitched seismic records of a single shot to generate a multi-shot stitched seismic record. For multi-shot seismic records, based on the corresponding overlaid stitched seismic records, the column data of the corresponding channel of the shot is restored from the stitched seismic records to generate multiple columns of data. Each column of the multiple columns of data is normalized to generate a multi-shot stitched seismic record. The dispersion energy map extraction module is used to extract the dispersion energy map of spliced ​​seismic records of multiple shots after stacking based on the phase shift method.

[0012] Thirdly, embodiments of this application provide an electronic device, including: a processor, a memory, and a communication bus, wherein the processor and the memory communicate with each other through the communication bus; the memory stores program instructions executable by the processor, and the processor can execute the method provided in the first aspect or any possible implementation of the first aspect by calling the program instructions.

[0013] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer instructions that cause a computer to perform the method provided in the first aspect or any possible implementation thereof.

[0014] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0015] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 A schematic flowchart of the seismic record enhancement signal method provided in an embodiment of the present invention; Figure 2 This is a comparison diagram of waveforms before and after time shift correction for the same recording from different guns in an embodiment of the present invention; Figure 3 This is a comparison diagram of single-shot multichannel seismic records and multichannel seismic records after superposition with different shot time-shift corrections according to an embodiment of the present invention; Figure 4 This is a comparison diagram of the dispersion energy of single-shot seismic records and multi-shot stacked seismic records of the vertical component in an embodiment of the present invention. Figure 5 This is a comparison diagram of the dispersion energy of single-shot seismic records and multi-shot stacked seismic records of the radial component in an embodiment of the present invention. Figure 6 This is a schematic diagram of the structure of the seismic record enhancement signal device provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be noted that the data in this embodiment are all derived from a comprehensive analysis and evaluation of historical test data and corresponding historical test results from the three months prior to this test. Those skilled in the art will understand that the determination of the above-mentioned parameters for any single item in this invention can be achieved by selecting the value with the highest percentage based on the data distribution as the preset standard parameter, using weighted summation to obtain the value as the preset standard parameter, substituting each historical data point into a specific formula and using the value obtained from that formula as the preset standard parameter, or other selection methods, as long as the invention can clearly define different specific situations in the single-item judgment process through the obtained values.

[0020] Current methods for improving signal-to-noise ratio (SNR) by superimposing signals rely on timing devices to record accurate seismic source excitation times. These methods are costly and inconvenient for field operations. Without timing devices, traditional superposition methods, which involve manually picking up the arrival time of the first wave of each seismic record and performing time-shift correction on different seismic records, suffer from phase errors in the final superposition result due to errors in the manually picked-up times. This significantly reduces the SNR of the seismic waves. Therefore, this invention provides a method for enhancing surface wave signals by superimposing multi-shot seismic records in complex geological conditions. This method determines the relative time delay between seismic records from different shots through cross-correlation calculations. It can align and superimpose seismic records from different shots in the time domain without the need for timing devices or manual picking of first wave signals. It offers advantages such as low cost, automation, and robustness, and is particularly suitable for environments where seismic wave energy is strongly attenuated, such as those with soft soil or high water content. It effectively enhances the SNR of surface wave signals and dispersion energy maps, improving the reliability of subsequent underground structure imaging.

[0021] Please see Figure 1 As shown, it is a flowchart of the method for enhancing surface wave signals by superimposing multi-shot seismic records based on complex geology according to an embodiment of the present invention.

[0022] To facilitate understanding of this embodiment, a detailed description of the method for enhancing surface wave signals based on multi-shot seismic record stacking in complex geology, as disclosed in this embodiment of the invention, is provided first, including: Step S1: Obtain multi-shot multichannel seismic records from the seismic station array deployed at the test site, and stitch the multichannel seismic records of each shot into a column of data in sequence to obtain the stitched seismic record of a single shot. Step S2: Based on cross-correlation analysis, determine the time shift between the mosaic seismic records of each shot. Using the first mosaic seismic record in the multi-shot multi-channel seismic record as the reference signal, perform cross-correlation analysis on each second mosaic seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Then, according to each of the relative time shifts, perform time-domain translation on the first mosaic seismic record in the single-shot mosaic seismic record to align the columns corresponding to the second mosaic seismic records in the single-shot mosaic seismic record with the columns corresponding to the first shot mosaic seismic record in the time domain, generating the aligned single-shot mosaic seismic record. Step S3: The aligned single-shot mosaic seismic records are superimposed to generate multi-shot mosaic seismic records. For multi-shot seismic records, the corresponding channel column data of the shot is restored from the mosaic seismic records to generate multi-column data. Each column of the multi-column data is normalized to generate multi-shot mosaic seismic records. Step S4: Extract the dispersion energy map of the stitched seismic record of multiple shots after stacking based on the phase shift method.

[0023] Specifically, this invention involves stitching multiple seismic records from various shots into a single long sequence, then using the first shot as a reference, estimating the time shift of each shot using cross-correlation, and aligning the stitched records of all shots in the time domain. After alignment, the records are superimposed and restored to the original number of traces, then normalized channel by channel. Finally, phase-shift analysis is performed on the superimposed records to obtain a dispersion energy map. Multi-shot alignment and superposition effectively enhances coherent surface wave signals, suppresses random noise and inter-shot inconsistencies, preserves inter-trace travel time information, and the restoration and normalization after superposition balance the energy differences between traces, resulting in a higher signal-to-noise ratio and more dispersion in the dispersion energy map extracted by the subsequent phase-shift method. The curves are clearer and more reliable. The relative time shift is determined and corrected by cross-correlation analysis of seismic records from different shots. Effective superposition of multi-shot seismic records is achieved even when the source excitation time of each shot is unknown or the arrival time of the first arrival seismic wave is difficult to pick accurately. The absence of a time synchronization device significantly reduces construction costs, and the time shift calculation results have good robustness. By superimposing multi-shot seismic records after time shift correction, random noise is suppressed, weak signals caused by strong attenuation under complex geological conditions are enhanced, and the signal-to-noise ratio of surface waves and the resolution of the corresponding dispersion energy map are improved, thereby improving the accuracy of subsequent surface wave dispersion curve picking.

[0024] Specifically, in step S1, the embodiment of the present invention acquires multi-shot multi-channel seismic records from an array of seismic stations arranged at the test site at a preset sampling rate. The multi-shot multi-channel seismic records are vibration signal data.

[0025] In this embodiment of the invention, the preset sampling rate is 1000Hz, but the above value is not limited to this, and those skilled in the art can adjust the value according to actual needs.

[0026] In a preferred embodiment of the present invention, a seismic survey line is laid out on the ground, and a hammer-driven seismic source is used to repeatedly excite the same location 5 times. Using 24 geophones, with a channel spacing of 1 meter, a minimum shot-receiver distance of 3 meters, and a preset sampling rate of 1000 Hz, 5-shot multichannel seismic records are acquired. For a single shot, the multichannel seismic record contains multiple time-series data columns, each column corresponding to the vibration signal record at a geophone location. To facilitate subsequent cross-correlation calculations between seismic records from different shots, this embodiment of the present invention performs splicing processing on the multichannel seismic records of each shot to obtain a spliced ​​seismic record for a single shot: all the seismic records of all channels, i.e., multiple data columns, are spliced ​​sequentially into a single data column. For any multichannel seismic record of a shot, its seismic record form is a two-dimensional array containing multiple time-series data columns. The number of columns is N, the number of columns is T, and the number of rows is T, the number of sampling points per channel. That is, for N channels of seismic records of a shot, each channel contains T sampling points, and the spliced ​​result is a single data column of length N×T.

[0027] Understandably, this two-dimensional array is concatenated column-wise. That is, the second data point (the second column) is directly appended to the end of the first data point (the first column), the third data point is appended to the second data point, and so on, until all N data points are concatenated. Ultimately, the N×T two-dimensional record of a single shot is converted into a one-dimensional signal of length N×T. ,in, Indicates the cannon number.

[0028] Specifically, this invention stitches together seismic records from active source surface waves, integrating multiple data columns from each shot's multi-channel seismic records into a single data column. This ensures that seismic records from different shots have the same data structure, facilitating direct cross-correlation calculations to determine their relative time shifts. Simultaneously, the stitched data retains all the time-series information of the original multi-channel records, ensuring that cross-correlation calculations fully utilize the signal characteristics at all detector locations, improving the accuracy and stability of time shift calculations. During the stitching process, no interpolation or filtering is performed between the data columns, maintaining the integrity and temporal continuity of the original sampling points and avoiding additional time deviations introduced by data processing. This enables accurate superposition of multi-shot seismic records even without a time synchronization device, thereby improving the signal-to-noise ratio.

[0029] Specifically, in step S2, the time shift of the stitched seismic records of each shot is determined by cross-correlation analysis, that is, the delay in the time domain.

[0030] Specifically, the embodiments of the present invention will include the first Pieced seismic records of cannons and the Pieced seismic records of cannons The cross-correlation function of the integrated mosaic seismic records is defined as follows:

[0031] in, Represents the time delay variable. express The complex conjugate of the summation can be understood as follows: for a signal of finite length, the summation range is the range of the signal with delay. The effective overlapping portion below.

[0032] Specifically, in this embodiment of the invention, given that the cross-correlation function of the integrated stitched seismic record has been determined, the maximum value or peak position of the cross-correlation function is searched to determine the first... Cannon and the First The relative time delay, or relative time shift, of the spliced ​​seismic records of the shots. ,Right now:

[0033] Understandably, the cross-correlation function Characterized the spliced ​​seismic record and Different time delays The degree of similarity, that is, when the first Translation of spliced ​​seismic records from guns Then, the first The waveform of the cannon and the first The waveform of the cannon is the most similar.

[0034] Specifically, in this embodiment of the invention, under the condition of obtaining the relative time delay, the first mosaic seismic record in the multi-shot multi-channel seismic record is used as the reference signal. The first mosaic seismic record is the mosaic seismic record of the first shot in the multi-shot multi-channel seismic record. Each second mosaic seismic record in the multi-shot multi-channel seismic record is cross-correlation analyzed with the reference signal to obtain the relative time shift of each shot relative to the first shot. ,in, , Given the total number of shots, the second mosaic seismic record is a mosaic seismic record of all shots except the first shot from a multi-shot, multi-channel seismic record. Under the condition of obtaining the relative time shift, a time-domain translation operation is performed on the mosaic seismic records of the other shots. The translation operation procedure is as follows: [The text then abruptly shifts to a different topic, mentioning the number of shots and the second mosaic seismic record.] The spliced ​​seismic records of the gun move along the time axis Each sampling point. When When it is positive, it indicates the first... The seismic records from the first shot are delayed compared to those from the second shot; therefore, the seismic records from the third shot need to be updated. The spliced ​​seismic records of the guns are shifted forward, that is, shifted in the direction of decreasing time. When it is negative, it indicates that the first... The seismic records from the first shot are ahead of those from the second shot, requiring the [missing information - likely a specific seismic sequence]. The spliced ​​seismic records from the cannons are shifted backward, that is, moved in the direction of increasing time.

[0035] Specifically, this invention eliminates the time deviation caused by inaccurate manual identification of the arrival time of the first arrival wave in traditional methods, and achieves accurate superposition of multi-shot seismic records without a time synchronization device. Through translation operation, the seismic records of all shots are aligned in the time domain, that is, the arrival time of the same seismic wave phase in each shot record is consistent. Since the cross-correlation calculation utilizes all waveform information of the entire stitched record, rather than relying solely on the single arrival time of the first arrival wave, it has stronger noise resistance and higher accuracy, thereby improving the signal-to-noise ratio.

[0036] Please see Figure 2 As shown, it is a comparison diagram of waveforms before and after time shift correction for the same channel recording of different guns in an embodiment of the present invention.

[0037] Specifically, by comparing the five-shot seismic signals recorded by the first geophone before time-shift correction with the five-shot seismic signals recorded by the first geophone after time-shift correction, it can be seen that the arrival time of the seismic waves is consistent and the waveforms have good consistency. This high degree of time consistency lays a solid foundation for subsequent multi-shot linear superposition, ensuring that the effective signals can be superimposed and enhanced in phase during the superposition process, while random noise cancels each other out due to the random phase.

[0038] Specifically, in step S3, the aligned single-shot seismic records are linearly superimposed, and under the condition that the seismic records of all shots are aligned in the time domain, the time-shift corrected multi-shot seismic records are superimposed and normalized to improve the signal-to-noise ratio of the surface wave signal and equalize the energy of each channel.

[0039] Specifically, in this embodiment of the invention, all time-shift corrected single-shot mosaic seismic records are superimposed, and the superposition formula is as follows:

[0040] in, The number of shots superimposed on the earthquake records. This is a composite earthquake record after being overlaid.

[0041] Understandably, for effective surface wave signals, since the positions of each shot source are the same or close, and the waveforms are aligned after precise time-shift correction, the amplitude of the superimposed effective signal is approximately equal to that of a single-shot signal. This means the signal energy is increased to the level of a single gun. The amplitude of the noise is increased by a factor of 10, while for random noise, since the noise from each shot is independent in time and space and has random phase, the amplitude of the superimposed noise is only increased by a factor of 10 of the noise from a single shot. This means the noise energy is increased to that of a single gun by a factor of [number missing]. Therefore, the signal-to-noise ratio, that is, the ratio of signal energy to noise energy, is increased to that of a single shot after superposition. This achieves a significant enhancement of the effective signal and effective suppression of random noise.

[0042] Specifically, in this embodiment of the invention, under the condition that the stitched seismic records corresponding to multiple shots are obtained, for multiple shots, based on the corresponding stitched seismic records, the stitched seismic records are restored to column data of the corresponding channel of the shot to generate multiple columns of data. The restoration process is as follows: a column of data with a length of N×T is divided into N columns of data in sequence, with each column consisting of T sampling points. Each column corresponds to the seismic record of a geophone position.

[0043] Specifically, in this embodiment of the invention, under the condition that the restored multi-column data is obtained, the restored multi-column data is normalized for each column. The normalization process is as follows: For each trace or column of spliced ​​seismic record, the maximum amplitude of that trace or the maximum absolute value of all sampling points in that column is found. Then, the value of each sampling point in that column is divided by the maximum value, so that the maximum amplitude value of each trace is normalized to 1. That is, the value of each sampling point is divided by the maximum value of the column in which each sampling point is located. The formula for the normalization process is expressed as:

[0044] in, For the first spliced ​​earthquake records before the unification of the Dao, For the first The stitched earthquake records after standardization For the first The maximum absolute value of the stitched seismic records.

[0045] Understandably, during surface wave propagation, due to geometric diffusion and medium absorption attenuation, the surface wave energy received by the far-channel detector (i.e., the detector with a larger shot-receiver distance) is significantly lower than that received by the near-channel detector (i.e., the detector with a smaller shot-receiver distance). Without normalization, in subsequent dispersion energy map calculations, the strong near-channel signal will dominate the energy distribution, suppressing the contribution of the weak far-channel signal. This results in insufficient resolution of the dispersion energy map in the low-frequency band for the long-wavelength surface waves of the far-channel, making it impossible to accurately extract the complete dispersion curve. By normalizing channel by channel, the relative amplitude relationship of each channel signal is readjusted, the energy of the weak far-channel signal is amplified, and its weight in the dispersion energy map calculation is increased, thus enabling the dispersion energy map to have high resolution and clear energy focusing across the entire frequency range.

[0046] Specifically, this invention achieves accurate superposition of multi-shot seismic records without a timing device by superimposing multiple shots. This effectively enhances weak signals caused by strong energy attenuation of seismic waves under complex geological conditions, allowing effective surface wave signals that were originally submerged by noise to emerge. This provides a high-quality data foundation for subsequent dispersion analysis, suppresses random noise, enhances weak signals caused by strong energy attenuation of seismic waves under complex geological conditions, increases the weight of weaker seismic wave signals located at distant points in the dispersion energy map calculation, and thus improves the signal-to-noise ratio.

[0047] Please see Figure 3 As shown, it is a comparison diagram of single-shot multichannel seismic records and multichannel seismic records after time-shift correction and superposition of different shots according to an embodiment of the present invention.

[0048] Specifically, this invention compares single-shot multichannel seismic records with multichannel seismic records superimposed after time-shift correction from different shots. It shows that, compared to single-shot seismic records, the time-shift corrected multichannel record superposition process achieves accurate superposition of multichannel seismic records even without a timing device. The effective seismic wave signal is significantly enhanced, the continuity of the phase axis is significantly improved, and random noise is significantly suppressed. Particularly in the far-channel region, weak surface wave signals that were almost completely obscured by noise in single-shot records become clearly discernible after superposition, fully verifying the effectiveness of this invention in enhancing weak signals and improving the signal-to-noise ratio.

[0049] Specifically, in step S4, the dispersion energy map of the stitched seismic record of multiple shots after stacking is extracted based on the phase shift method. The phase shift method is based on the fact that different frequency components of surface waves have different phase velocities when propagating in a layered medium. By converting the seismic record in the time-space domain to the frequency-phase velocity domain, the distribution law of surface wave energy can be observed intuitively, and then the dispersion curve can be extracted.

[0050] Specifically, in this embodiment of the invention, under the condition that the superimposed and normalized multi-channel mosaic seismic records are obtained, the multi-channel mosaic seismic records are... A one-dimensional Fourier transform is performed along the time direction to convert the multi-channel mosaic seismic record from the time-space domain to the frequency-space domain, yielding the spectrum of the multi-channel mosaic seismic record. The spectrum is represented as:

[0051] in, For the gun-receiver distance, It is the angular frequency. For time.

[0052] The spectrum can also be represented as an amplitude spectrum. Phase spectrum The product form:

[0053] Among them, amplitude spectrum The phase spectrum reflects the effect of cylindrical diffusion on amplitude and the attenuation characteristics of the medium. By preserving the wave's travel time information, i.e., its phase information, it can be understood that, under the far-field approximation, the wave's diffusion mode can be considered as planar diffusion, and the phase spectrum can be expressed as:

[0054] in, Frequency components The corresponding phase velocity.

[0055] Specifically, in order to eliminate the influence of cylindrical diffusion and medium attenuation in the amplitude spectrum on the calculation of dispersion energy, the embodiments of the present invention perform normalization processing on the amplitude spectrum, that is, divide each spectrum by the magnitude of the amplitude spectrum of each spectrum to obtain the normalized spectrum. Then, scanning is performed within the possible phase velocity range, and for each scan phase velocity... Calculate the normalized spectrum and corresponding phase correction factor for each channel. The sum of the products of these factors yields the dispersion energy, which is expressed as:

[0056] in, To receive the number of channels, For the first The gun-receiver distance of the track, This represents the scanning phase velocity.

[0057] It is understandable that, for a certain frequency When the scanning phase velocity Equal to the true phase velocity corresponding to the frequency At that time, the phase correction factors of each channel exactly compensate for the phase difference of the original signal, so that the summation results are superimposed in phase, and the dispersion energy is reduced. When the scanning phase velocity reaches its maximum value... Deviation from true phase velocity When the phases of the signals are inconsistent, the summation results cancel each other out, resulting in relatively small dispersion energy. Therefore, by calculating the dispersion energy corresponding to all frequencies and scanning phase velocities on the frequency-phase velocity plane, a two-dimensional dispersion energy map can be obtained. The energy maxima in the map correspond to the true dispersion relationship of the surface wave.

[0058] Please see Figure 4 As shown, it is a comparison diagram of the dispersion energy of single-shot seismic records and multi-shot stacked seismic records of the vertical component in an embodiment of the present invention.

[0059] Please see Figure 5 As shown, it is a comparison diagram of the dispersion energy of single-shot seismic records and multi-shot stacked seismic records of the radial component in an embodiment of the present invention.

[0060] Specifically, this invention extracts the dispersion energy map of the stacked seismic signals, and compares the dispersion energy map of the multi-shot stacked seismic records with the dispersion energy maps of single-shot seismic records of the vertical component or the radial component, from... Figure 4 As can be observed, compared with the dispersion energy map calculated from single-shot seismic records, the dispersion energy map calculated based on the stacked seismic records has significant advantages. The energy clusters are more convergent and focused, the boundaries are clearer, the resolution is significantly improved, the continuity and integrity of the energy clusters of the fundamental mode Rayleigh wave are better, making it easier to accurately pick the dispersion curves, the noise background is significantly reduced, the contrast between the energy clusters and the background is enhanced, and the possibility of mode misjudgment is reduced. It can be seen that, whether in the vertical component or the radial component, the dispersion energy map calculated based on the stacked seismic records has a higher resolution than the dispersion energy map calculated from single-shot multi-channel seismic records, and the energy clusters of Rayleigh waves of different modes are clearer. It realizes accurate stacking of multi-shot seismic records without a timing device, thereby improving the signal-to-noise ratio.

[0061] Please see Figure 6 As shown, this is a structural schematic diagram of a seismic record enhancement signal device 200 provided in an embodiment of the present invention. The device includes: The stitched seismic record generation module 210 is used to acquire multi-shot multichannel seismic records from the seismic station array deployed at the test site, and stitch the multichannel seismic records of each shot into a column of data in sequence to obtain the stitched seismic record of a single shot. The seismic record time-shift module 220 is used to determine the time shift between the seismic records of each shot based on cross-correlation analysis. Taking the first seismic record in the multi-shot multi-channel seismic record as the reference signal, cross-correlation analysis is performed on each second seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Based on the relative time shift, the first seismic record in the single-shot seismic record is shifted in the time domain to align the columns corresponding to the second seismic records in the single-shot seismic record with the columns corresponding to the first seismic record in the time domain, thereby generating the aligned single-shot seismic record. The stitched seismic record overlay module 230 is used to overlay the stitched seismic records corresponding to each shot in the aligned single-shot stitched seismic records to generate a stitched seismic record corresponding to each shot. For each shot, based on the corresponding stitched seismic record, the single-shot stitched seismic record is restored to column data of the corresponding channel to generate multiple columns of data. Each column of the multiple columns of data is normalized to generate a multi-shot stitched seismic record. The dispersion energy map extraction module 240 is used to extract the dispersion energy map of the stitched seismic record of multiple shots after stacking based on the phase shift method.

[0062] The device provided in this application embodiment has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0063] Please see Figure 7 As shown, it is a schematic diagram of an electronic device provided in an embodiment of the present invention. Figure 7 The electronic device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0064] Specifically, the electronic device 300 includes a processor 310, a memory 320, and a communication interface 330, which are interconnected and communicate with each other via a communication bus 340 and / or other forms of connection mechanism (not shown).

[0065] The memory 320 includes one or more (only one is shown in the figure), which may be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The processor 310 and other possible components may access the memory 320 to read and / or write data therein.

[0066] Processor 310 includes one or more (only one is shown in the figure), which can be an integrated circuit chip with signal processing capabilities. The processor 310 described above can be a general-purpose processor, including a central processing unit (CPU), a microcontroller unit (MCU), a network processor (NP), or other conventional processors; it can also be a special-purpose processor, including a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0067] The communication interface 330 includes one or more (only one is shown in the figure) and can be used to communicate directly or indirectly with other devices to exchange data. For example, the communication interface 330 can be an Ethernet interface; it can be a mobile communication network interface, such as an interface for 3G, 4G, or 5G networks; or it can be other types of interfaces with data transmission and reception functions.

[0068] One or more computer program instructions may be stored in memory 320, and processor 310 may read and run these computer program instructions to implement the seismic record enhancement signal method provided in the embodiments of this application and other desired functions.

[0069] Understandable. Figure 7The structure shown is for illustrative purposes only; the electronic device 300 may also include components that are more advanced than those shown. Figure 7 The more or fewer components shown, or having the same Figure 7 The different configurations shown. Figure 7 The components shown can be implemented using hardware, software, or a combination thereof. For example, electronic device 300 can be a single server (or other device with computing power), a combination of multiple servers, a cluster of a large number of servers, etc., and can be either a physical device or a virtual device.

[0070] This application also provides a computer-readable storage medium storing computer program instructions. These computer program instructions are read and executed by a computer processor to perform the seismic record enhancement signal method provided in this application. For example, the computer-readable storage medium can be implemented as follows: Figure 7 The memory 320 in the electronic device 300.

[0071] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings or direct couplings or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0072] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0073] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0074] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present application should be included within the scope of protection of the present application.

Claims

1. A method for enhancing seismic record signals, characterized in that, include: Acquire multi-shot, multi-channel seismic records from the seismic station array deployed at the test site, and stitch the multi-channel seismic records from each shot into a single column of data to obtain the stitched seismic record of a single shot. Based on cross-correlation analysis, the time shift between the mosaic seismic records of each shot is determined. Taking the first mosaic seismic record in the multi-shot multi-channel seismic record as the reference signal, cross-correlation analysis is performed on each second mosaic seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Based on the relative time shift, the first mosaic seismic record in the single-shot mosaic seismic record is shifted in the time domain to align the columns corresponding to the second mosaic seismic records in the single-shot mosaic seismic record with the columns corresponding to the first shot mosaic seismic record in the time domain, generating the aligned single-shot mosaic seismic record. The aligned single-shot mosaic seismic records are superimposed to generate multi-shot mosaic seismic records. For multi-shot seismic records, the corresponding channel column data of the shot is restored from the mosaic seismic records to generate multi-column data. Each column of the multi-column data is then normalized to generate multi-shot mosaic seismic records. Dispersion energy maps of multi-shot seismic records after stacking were extracted using the phase-shift method.

2. The seismic record enhancement signal method according to claim 1, characterized in that, The process of determining the time shift between the stitched seismic records of each shot based on cross-correlation analysis is as follows: The stitched seismic records of each shot are integrated using a cross-correlation function, and the integrated stitched seismic records are output. The maximum and minimum values ​​for each shot in the integrated mosaic seismic record are searched to determine the time shift between the mosaic seismic records for each shot.

3. The seismic record enhancement signal method according to claim 2, characterized in that, The cross-correlation function is expressed as: ， in, Represents the time delay variable. Indicates the first The spliced ​​seismic records of the cannons express .

4. The seismic record enhancement signal method according to claim 1, characterized in that, The translation process includes: moving the stitched seismic records of each shot along the time axis by the relative time shift of each shot relative to the first shot by 1 sampling point. When the relative time shift is positive, it indicates that there is a delay in each shot relative to the first shot, and the stitched seismic records of each shot need to be moved in the direction of decreasing time. When the relative time shift is negative, it indicates that each shot is ahead of the first shot, and the stitched seismic records of each shot need to be moved in the direction of increasing time.

5. The method for enhancing seismic record signals according to claim 1, characterized in that, The method for stacking aligned single-shot seismic records is determined based on the following formula: ， in, The number of shots superimposed on the earthquake records. This is a composite earthquake record after being overlaid. This represents the relative time shift of each gun relative to the first gun.

6. The method for enhancing seismic record signals according to claim 1, characterized in that, The normalization process includes: for each trace or column of spliced ​​seismic records, finding the maximum amplitude of the corresponding trace or the maximum absolute value of all sampling points in the corresponding column, and then dividing the value of each sampling point in the corresponding column by the corresponding maximum value, so that the maximum amplitude value of each trace is normalized to 1.

7. A seismic record enhancement signal device, characterized in that, include: The stitched seismic record generation module is used to acquire multi-shot multichannel seismic records from the seismic station array deployed at the test site, and stitch the multichannel seismic records of each shot into a column of data in sequence to obtain the stitched seismic record of a single shot. The seismic record time-shift module is used to determine the time shift between the seismic records of each shot based on cross-correlation analysis. Taking the first seismic record in the multi-shot multi-channel seismic record as the reference signal, cross-correlation analysis is performed on each second seismic record in the multi-shot multi-channel seismic record with the reference signal to obtain the relative time shift of each shot relative to the first shot. Based on the relative time shift, the first seismic record in the single-shot seismic record is shifted in the time domain to align the columns corresponding to the second seismic records in the single-shot seismic record with the columns corresponding to the first seismic record in the time domain, generating the aligned single-shot seismic record. The stitched seismic record overlay module is used to overlay the aligned stitched seismic records of a single shot to generate a multi-shot stitched seismic record. For multi-shot seismic records, based on the corresponding overlaid stitched seismic records, the column data of the corresponding channel of the shot is restored from the stitched seismic records to generate multiple columns of data. Each column of the multiple columns of data is normalized to generate a multi-shot stitched seismic record. The dispersion energy map extraction module is used to extract the dispersion energy map of spliced ​​seismic records of multiple shots after stacking based on the phase shift method.

8. An electronic device, characterized in that, include: A processor, a memory, and a communication bus, wherein the processor and the memory communicate with each other via the communication bus; The memory stores program instructions that can be executed by the processor, which can invoke the program instructions to perform the seismic record enhancement signal method as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause the computer to perform the seismic record enhancement signal method as described in any one of claims 1 to 6.

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