CN-118625378-B - Method, equipment and storage medium for identifying and suppressing single-frequency interference of seismic data

CN118625378BCN 118625378 BCN118625378 BCN 118625378BCN-118625378-B

Abstract

Defining an observation system, acquiring seismic data, extracting a seismic channel set, deriving signal data of the seismic channel set, mirror-turning the signal data of the seismic channel set, performing normalization processing to obtain signal data for identifying the seismic channel set, calculating an average cross-correlation coefficient of the seismic channel set according to the signal data of the seismic channel set for identification, determining whether the seismic channel set contains single-frequency interference, calculating high-precision single-frequency interference frequency of each seismic channel in the seismic channel set when the seismic channel set is determined to contain the single-frequency interference, calculating actual single-frequency interference of the seismic channel set based on the high-precision single-frequency interference frequency of each seismic channel in the seismic channel set, and further suppressing the single-frequency interference; the device and the storage medium are used for realizing the method, and have the beneficial effects of conforming to the characteristics of seismic data, better identifying single-frequency interference and avoiding the influence caused by the energy abnormality of the near offset of the earthquake.

Inventors

LIU LIAN
CHEN SONG
ZHENG XUEJING
CHEN LINGYU

Assignees

安徽省勘查技术院(安徽省地质矿产勘查局能源勘查中心)

Dates

Publication Date: 20260505
Application Date: 20240603

Claims (7)

1. A method for identifying and suppressing single-frequency interference of seismic data is characterized by comprising the following specific steps: s1, defining an observation system, acquiring seismic data, extracting a seismic trace set and deriving signal data of the seismic trace set, wherein the seismic trace set is a set of seismic traces of common detection points extracted after the seismic data suppress abnormal amplitudes, the data in the seismic trace set are defined by amplitude data after the first arrival time of the earthquake according to the arrangement of offset distances from small to large, and the derivation form of the seismic trace set is as follows: In the formula, The method comprises the steps of acquiring a function of i and j, wherein the function is used for representing signal data of an nth seismic trace set, n is a seismic trace set serial number, i is the number of acquired samples after the first arrival time of the seismic trace set, and j is the number of seismic traces in the nth seismic trace set; amplitude after the first arrival time of the earthquake channel; S2, mirror-turning and normalizing the signal data of the seismic gather to obtain the signal data for identifying the seismic gather, wherein the signal data specifically comprises the following steps of: S21, performing matrix array vector element mirror image overturning processing on signal data of the seismic trace set, wherein the mathematical expression is as follows: In the formula, Representing the mirror image inversion processing result of the nth seismic gather signal data as a function of i, j; s22, carrying out normalization processing on the seismic gather signal data after the mirror image overturning processing to obtain signal data for seismic gather identification, wherein the mathematical expression is as follows: In the formula, Representing the identification signal data of the nth seismic gather as a function of i, j; S3, calculating the average cross correlation coefficient of the seismic trace set according to the signal data for identifying the seismic trace set, and determining whether the seismic trace set contains single-frequency interference; S4, when the seismic channel set is determined to contain single-frequency interference, calculating high-precision single-frequency interference frequency of each seismic channel in the seismic channel set; s5, calculating actual single-frequency interference of the seismic trace set based on high-precision single-frequency interference frequency of each seismic trace in the seismic trace set, and further suppressing the single-frequency interference, wherein the method specifically comprises the following steps: S51, calculating corresponding amplitude according to high-precision single-frequency interference frequencies of all seismic channels in the seismic channel set, and reconstructing single-frequency interference of the seismic channels; S52, acquiring a single-frequency interference discrete form of the seismic trace set according to the reconstructed single-frequency interference of the seismic trace, and then performing matrix array vector element mirror image overturning treatment to obtain the actual single-frequency interference of the seismic trace set; s53, subtracting the actual single-frequency interference from the signal data of the seismic trace set to achieve the purpose of suppressing the single-frequency interference.
2. The method of claim 1, wherein the seismic data is single shot recorded data received by a plurality of receivers.
3. The method for identifying and suppressing single-frequency interference of seismic data according to claim 1, wherein the single-frequency interference is a discrete mathematical model, and the remaining string models are represented as follows: In the formula, Is single frequency interference; Representing the actual amplitude of the single-frequency interference, Representing the amplitude of the cosine function after decomposing the single-frequency interference, The amplitude of the sine function after decomposing the single-frequency interference is expressed, and the three have a corresponding relation ; Phase for single frequency interference; frequency of single-frequency interference; is the sampling time interval.
4. A method of single frequency interference identification and suppression of seismic data as claimed in claim 3 wherein the presence or absence of single frequency interference in the seismic gather is determined by the average cross correlation coefficient of the seismic gather, and when the average cross correlation coefficient of the seismic gather exceeds a threshold, the single frequency interference is present in the seismic gather; The average cross-correlation coefficient of the seismic channel set is a weighted average result of the cross-correlation coefficient of the seismic channels, and the calculation formula is as follows: In the formula, Average cross correlation coefficient for the nth seismic gather; The cross-correlation coefficient of the jth seismic trace in the seismic trace set is represented by the following calculation formula: In the formula, Cosine cross-correlation coefficient for the jth seismic trace in the seismic trace set, For the sine cross-correlation coefficient of the jth seismic trace in the seismic trace set, the calculation formula is as follows: 。
5. The method for identifying and suppressing single-frequency interference of seismic data as claimed in claim 4, wherein said high-precision single-frequency interference frequency calculation step comprises the steps of: According to the frequency spectrum analysis of the seismic channel set, obtaining the initial frequency of each seismic channel, and according to the relation between the frequency and the amplitude in the single-frequency interference, gradually increasing the precision on the basis of the initial single-frequency interference frequency to obtain the high-precision single-frequency interference frequency of each seismic channel in the seismic channel set; Wherein, the function of the relation between the frequency and the amplitude in the single-frequency interference is expressed as follows: According to Will preset the frequency accuracy level to make the amplitude The frequency reaching the maximum value is used as the high-precision single-frequency interference frequency of the jth seismic trace in the seismic trace set.
6. A storage medium is characterized in that the storage medium stores instructions and data for realizing the method for identifying and suppressing single-frequency interference of seismic data according to any one of claims 1-5.
7. A computer device is characterized by comprising a processor and a storage medium, wherein the processor loads and executes instructions and data in the storage medium to realize the method for identifying and suppressing single-frequency interference of seismic data according to any one of claims 1-5.

Description

Method, equipment and storage medium for identifying and suppressing single-frequency interference of seismic data Technical Field The invention relates to the field of seismic data digital processing, in particular to a method, equipment and a storage medium for identifying and suppressing single-frequency interference of seismic data. Background The seismic data processing process frequently encounters strong-energy single-frequency interference noise data, the conventional single-frequency interference recognition is usually carried out in a frequency domain, and the abnormal 'convex' value (Yuan et al, 2021) of each single-frequency interference frequency domain is searched, so that the single-frequency interference noise data is difficult to recognize when the amplitude of the interference frequency domain is weaker than the frequency of the whole seismic gather. Chen Keyang et al propose to calculate the cross-correlation normalization coefficient in the time domain to judge whether the seismic trace set contains single-frequency interference (Chen Keyang et al, 2014), the calculation method is to assume that the seismic trace set contains single-frequency interference, fit the amplitude, frequency and phase of the single-frequency interference signal by a least square method, then use the fitted single-frequency interference signal and the seismic trace set to do cross-correlation to obtain a normalization coefficient, judge whether the single-frequency interference exists according to the coefficient, the algorithm is complex, and the method is not suitable for the requirement of the calculation efficiency of the mass data of the seismic data. The prior references do not discuss the effect of suppressing single-frequency interference of the near-trace data of the seismic trace, and some papers propose to estimate the single-frequency interference frequency and amplitude by using the deep data of the seismic data. In other papers, automatic gain is proposed to equalize the energy of the seismic data, but the near single-frequency interference after automatic gain is not the complete harmonic interference, and still cannot suppress the single-frequency interference. Disclosure of Invention The invention aims to solve the problem of difficult single-frequency interference suppression of seismic trace near data, and provides a single-frequency interference recognition and suppression method, equipment and a storage medium for seismic data, wherein the single-frequency interference recognition and suppression method for seismic data mainly comprises the following steps: S1, defining an observation system, acquiring seismic data, extracting a seismic trace set and deriving signal data thereof; S2, mirror-turning and normalizing the signal data of the seismic gather to obtain signal data for identifying the seismic gather; s3, calculating the average cross correlation coefficient of the seismic gather according to the signal data of the seismic gather for identification, and determining whether the seismic gather contains single-frequency interference; S4, when the seismic channel set is determined to contain single-frequency interference, calculating high-precision single-frequency interference frequency of each seismic channel in the seismic channel set; S5, calculating actual single-frequency interference of the seismic channel set based on the high-precision single-frequency interference frequency of each seismic channel in the seismic channel set, and further suppressing the single-frequency interference. Further, the seismic data is single shot recorded data, and is received by a plurality of detection points. Further, the seismic trace set is a set of seismic traces of common detection points extracted after the seismic data suppress abnormal amplitudes, the data in the seismic trace set is defined by amplitude data below the first arrival time of the earthquake according to the arrangement of offset from small to large, and the derivation form of the seismic trace set is as follows: Wherein s (n) is a function of i, j and represents signal data of an nth seismic gather, n is a seismic gather sequence number, i is the number of acquisition samples below the first arrival time of the seismic gather, j is the number of seismic gathers of the nth seismic gather, and s ij is the amplitude below the first arrival time of the seismic gather. Further, the step S2 specifically includes: S21, performing matrix array vector element mirror image overturning processing on signal data of the seismic trace set, wherein the mathematical expression is as follows: wherein srev (n) is a function of i, j, and represents the mirror image turning processing result of the nth seismic gather signal data; S22, carrying out normalization processing on the seismic gather signal data after the mirror image overturning processing to obtain the seismic gather signal data, wherein the mathematical expression is as follows: srevn