A serial induction quality control method based on reverse correlation of seismic scanning signals

Abstract

The present application provides a string induction quality control method based on reverse correlation of seismic scanning signals, which is used for quality control of oil and gas seismic exploration data acquisition. The method includes: inputting original correlated single-shot data of a controllable vibrator and a controllable vibrator scanning signal; reversing the sequence of the controllable vibrator scanning signal to obtain an inverse sequence; cross-correlating the original correlated single-shot data with the inverse sequence of the scanning signal; defining variables, arrays, and matrices for identifying string induction interference shots; calculating the average value of a specified channel of the secondary correlation data to generate a standard channel matrix; using the standard channel matrix to generate a local peak identification matrix and an index array; using the local peak identification matrix to generate a peak index maximum continuous channel number array; and using the local peak index maximum continuous channel number array to identify string induction interference shots.

Description

Technical Field

[0001] The present invention belongs to the technical field of quality control of oil and gas seismic exploration data acquisition, and in particular relates to a serial induction quality control method based on reverse correlation of seismic scanning signals. Background Art

[0002] With the advancement of seismic exploration and acquisition technology, the sensitivity and signal accuracy of acquisition equipment have been greatly improved, and the resolution of seismic data has been enhanced. However, interference is ubiquitous in seismic exploration, and crosstalk interference is a common interference signal. If its energy is strong enough to interfere with the target layer, it can seriously affect the seismic data. In field quality control of seismic data, once crosstalk interference is discovered, measures such as on-site re-shooting and alignment rectification are required immediately. If it is discovered too late, it will result in a large number of wasted shots during production, or the delayed re-shooting will delay field production progress, ultimately placing significant operational pressure on the project.

[0003] In well-shot seismic records or original uncorrelated single-shot seismic records from vibrators, string-induced interference signals typically appear simultaneously on a group (or all) of consecutive seismic traces, with waveforms resembling a pulse train. Therefore, in field production, this signal is vividly referred to as "string-induced interference." However, in correlated single-shot seismic records obtained by cross-correlating the original uncorrelated single-shot seismic records with the sweep signal, the string-induced interference signal appears as a truncated inverse sequence of the vibrator sweep signal in the correlated single-shot data due to the correlation operation. This results in the amplitude strength of the string-induced interference signal in the seismic record being unclear from that of other surrounding wavefields, making it difficult to accurately and automatically identify. In actual vibrator acquisition projects, especially for efficient vibrator acquisition, due to data storage space limitations, only the correlated single-shot data files are often saved. This significantly increases the difficulty of quality control for string-induced interference in vibrator seismic records. Therefore, the identification of string induction signals in the original correlated single-shot data records of the controllable source has become a difficult point in on-site quality control work.

[0004] For single-shot data records from correlated vibroseis sources, crosstalk interference can be identified by exploiting the similarity between seismic traces, based on the fact that crosstalk signals appear as incomplete inverse sequences of the vibroseis sweep signal. Therefore, calculating and comparing the similarity coefficients between adjacent seismic trace waveforms can be used as a method for crosstalk signal identification and quality control. However, the amplitude of the crosstalk signal in single-shot data records from correlated vibroseis sources is not significantly different from that of other surrounding wavefields, and uncertainties such as environmental interference make crosstalk signals even more difficult to identify. Therefore, crosstalk identification using the similarity coefficients between adjacent seismic trace waveforms can result in a certain degree of misjudgment. Furthermore, since the crosstalk signal in correlated vibroseis source shot data records contains information about the inverse sequence of the vibroseis sweep signal, anti-correlation operations can be performed on the correlated single-shot data records using the vibroseis sweep signal to restore the pulse characteristics of the crosstalk signal to a certain extent. Crosstalk interference can then be identified by pulse identification. However, on the one hand, the string induction signal in each shot-related single-shot record only exhibits partial, rather than complete, inverse sequence characteristics of the sweep signal. On the other hand, the occurrence of the string induction signal in each shot seismic record is uncertain, resulting in different frequency bands of the sweep signal inverse sequence exhibited by the string induction signal. Therefore, using a unified vibroseis sweep signal to perform anti-correlation on the vibroseis-related single-shot data records severely weakens the pulse characteristics of the string induction signal. This also makes it difficult to effectively identify string induction interference using this method. To address this issue, a new string induction quality control method based on inverse correlation of sweep signals has been developed to overcome these technical issues. Summary of the Invention

[0005] The purpose of the present invention is to provide a string induction quality control method based on reverse correlation of seismic scanning signals to improve the quality control accuracy of string induction interference guns that occur during vibroseis seismic acquisition, as well as the effect of subsequent indoor data processing. To achieve the above purpose, the method of the present invention includes the following steps:

[0006] Step 1: Input the original correlated single-shot seismic data matrix D of the vibrator:

[0007]

[0008] Where, d i represents the i-th data in the original correlated single-shot seismic data matrix D of the vibrator, d j'i Indicates the i-th data d iThe j'th sampling point in , n represents the number of channels of the original correlated single-shot seismic data matrix D of the vibrator, and m' represents the number of sampling points of each channel of seismic data in the original correlated single-shot seismic data matrix D of the vibrator;

[0009] Input vibrator scanning signal sequence sw:

[0010]

[0011] Where sw k' represents the k'th sampling point in the vibrator scanning signal sequence sw, n' represents the number of sampling points in the vibrator scanning signal sequence sw, and in actual situations, n'>m';

[0012] Step 2: reverse the order of the vibroseis scanning signal sequence sw to obtain the reverse sequence of the vibroseis scanning signal Then we have:

[0013] When k"+k'=n'+1, we have

[0014] Where, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points n' is the same as the number of sampling points of the vibroseis scanning signal sequence sw;

[0015] Step 3: Each data in the input vibroseis original correlation single shot seismic data matrix D is respectively compared with the inverse sequence of the vibroseis scanning signal Perform cross-correlation operations to obtain the data of each secondary correlation seismic trace. Then, sort the seismic trace data obtained after the secondary correlation operation according to the trace order corresponding to the controllable source original correlation single-shot seismic data matrix D to form the controllable source secondary correlation single-shot seismic data matrix X. The matrix X is expressed as follows:

[0016]

[0017] Where x i represents the i-th data in the matrix X of the secondary correlation single shot seismic data of the vibrator, x ji Represents the i-th data x iThe jth sampling point in the matrix X is n, which is the number of channels in the matrix X of the secondary correlation single shot seismic data of the vibrator. Then the number n is the same as the number of channels in the matrix D of the original correlation single shot seismic data of the vibrator. m is the number of sampling points of each channel of seismic data in the matrix X of the secondary correlation single shot seismic data of the vibrator. According to the relevant operation rules, m = m' + n' - 1, where m' is the number of sampling points of each channel of seismic data in the matrix D of the original correlation single shot seismic data of the vibrator, and n' is the inverse sequence of the scanning signal of the vibrator. The number of sampling points;

[0018] The i-th data d in the original correlated single-shot seismic data matrix D of the vibrator is i Inverse sequence with vibroseis scanning signal Perform cross-correlation operation to obtain the i-th data x in the vibroseis secondary correlation single shot seismic data matrix X i The calculation formula is as follows:

[0019]

[0020] Where x ji represents the i-th data x in the matrix X of the secondary correlation single shot seismic data of the vibrator i The jth sampling point in m represents the related single-channel seismic data x i The number of sampling points, Represents the correlation operator, d j'i represents the i-th data d in the original correlated single-shot seismic data matrix D of the vibrator i The j'th sampling point in m' represents the original single-channel seismic data d i The number of sampling points, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points;

[0021] Step 4: Define the following variables, arrays, or matrices for subsequent string induction jammer identification:

[0022] Define an empty local peak index array pv to store the index positions of the subsequently identified local peaks;

[0023] Define an empty maximum continuous channel number array pn that matches the local peak index array pv to store the maximum continuous channel number corresponding to the index position of each local peak identified subsequently;

[0024] Define a local peak identification matrix \(P\) of order \(m\times n\), and initialize this matrix as a zero matrix, which is used to store the local peak identifications corresponding to each sampling point position of the vibroseis secondary correlation single-shot seismic data matrix \(X\); \(P\) is expressed as follows:

[0025]

[0026] In the formula, \(p\) i represents the local peak identification array of the \(i\)-th trace of the local peak identification matrix \(P\), and \(p\) ji represents the \(j\)-th local peak identification in the local peak identification array \(p\) i ; \(n\) represents the number of traces of the local peak identification matrix \(P\) (this number of traces is the same as the number of traces of the vibroseis secondary correlation single-shot seismic data matrix \(X\)), and \(m\) represents the number of sampling points of each local peak identification array in the local peak identification matrix \(P\) (this number of sampling points is the same as the number of sampling points of each trace of seismic data in the vibroseis secondary correlation single-shot seismic data matrix \(X\)); in subsequent steps, local peaks will be screened out from the secondary correlation single-shot data matrix \(X\) according to specified conditions, and the sampling point values at the corresponding positions in the local peak identification matrix \(P\) will be reset according to the numerical signs (positive or negative signs) of these screened local peaks;

[0027] Define a maximum consecutive trace number threshold \(threshold\), and set \(threshold = 10\), which is used as the evaluation basis for determining whether the original correlation single-shot seismic data of the vibroseis is a series induction interference shot in the subsequent process;

[0028] Step 5, for each trace of seismic data in the vibroseis secondary correlation single-shot seismic data, calculate the average value of the seismic traces within the adjacent specified trace index range, and use it as the standard trace corresponding to each trace of secondary correlation data, thereby generating a standard trace matrix;

[0029] Calculate the standard trace corresponding to each trace of the vibroseis secondary correlation single-shot seismic data matrix \(X\) with the number of traces \(n\) respectively. The calculation formula is as follows:

[0030]

[0031] In the formula, \(s\) i represents the standard trace corresponding to the \(i\)-th trace of the vibroseis secondary correlation single-shot seismic data matrix \(X\), where \(1\leq i\leq n\); \(p\) represents the starting trace index for obtaining the standard trace \(s\) i : when \(i > 5\), set \(p = i - 5\), otherwise, set \(p = 1\); \(q\) represents the ending trace index for obtaining the standard trace \(s\) i : when \(i < n - 5\), set \(q = i + 5\), otherwise, set \(q = n\); \(k\) represents the trace index participating in the calculation of the standard trace \(s\) i ; \(x\) jkIndicates participation in standard channels i Calculate the kth data x k The jth sampling point in s ji Indicates standard road i The jth sampling point, m represents the standard track s i The number of sampling points m is the same as the number of sampling points of each seismic data in the matrix X of the secondary correlation single shot seismic data of the vibroseis;

[0032] Afterwards, the obtained standard trace data are sorted in the same trace order as the vibroseis secondary correlation single-shot seismic data matrix X to form a standard trace matrix S. The matrix S is expressed as follows:

[0033]

[0034] Where s i represents the i-th standard track data in the standard track matrix S, s ji Indicates the i-th data s i The j-th sampling point in , n represents the number of channels in the standard channel matrix S, and the channel number n is the same as the channel number of the vibroseis secondary correlation single shot seismic data matrix X;

[0035] Step 6: Use the generated standard trace matrix to identify the local peaks in the vibroseis secondary correlation single-shot seismic data, and obtain a local peak identification matrix by identifying the numerical signs (positive and negative) of the local peaks. At the same time, the sampling point index of the local peak is recorded in the local peak index array;

[0036] Using the standard trace matrix S, all local peaks with sampling point index l and trace index t that meet the requirements are screened from the vibroseis secondary correlation single-shot seismic data matrix S according to the following conditions. The specific screening conditions are as follows:

[0037] 1) In the standard trace matrix S, the local peak value x in the matrix X of the secondary correlation single shot seismic data of the vibrator is lt Sampling point s with the same sampling point index l and track index t lt , should be the t-th standard track data s t The sampling point with the largest absolute value from the ath to the bth sampling point in [1]. Where a is the larger value of t-20 / si and 1, b is the smaller value of t+20 / si and the number of sampling points m, and si is the sampling rate of the seismic data.

[0038] 2) In the matrix X of vibroseis secondary correlation single-shot seismic data, from the gth to the hth data, the number of data channels whose absolute value of the lth sampling point is greater than the absolute value of the sampling point before and after it 4 ms apart, divided by h-g+1, should be greater than 70%; where g is the larger of t-5 and 1, h is the smaller of t+5 and the number of channels n, and t is the channel index of the local peak;

[0039] 3) In the matrix X of the secondary correlation single shot seismic data of the vibroseis, the local peak x with sampling point index l and trace index t lt The absolute value of should be greater than the absolute value of the sampling point before and after it with a spacing of 4ms in the same channel;

[0040] Then, in the matrix X of the secondary correlation single shot seismic data of the vibroseis, all local peaks x with sampling point index l and trace index t that meet the above conditions are selected. lt The numerical sign (positive or negative) of the local peak identification matrix P is used to identify each local peak identification sampling point p with the same sampling point index l and track index t. lt Reset the value of: If x lt is positive, let p lt =1; if x lt is negative, let p lt =-1; and add the sampling point index l corresponding to all local peaks to the local peak index array pv;

[0041] Step 7, using the obtained local peak identification matrix, counting the maximum number of consecutive channels at each local peak index position, and generating a local peak index maximum consecutive channel number array;

[0042] For each local peak index c represented by each element value in the local peak index array pv, a column vector that meets the requirements is screened from the local peak identification matrix P according to the following conditions. The specific screening conditions are as follows:

[0043] 1) The absolute value of at least one of the c-1th, cth, and c+1th elements of this column vector must be 1;

[0044] 2) If the column index of this column vector in the local peak identification matrix P is greater than 1, then in the matrix P, the product of the c-th element value of the column vector and the c-th element value of the column vector of the adjacent previous column should be no less than 0, and when this product is equal to 0, the c-th element value of the column vector of the adjacent previous column should be equal to 0;

[0045] For each local peak index c represented by each element value in the local peak index array pv, after selecting the column vectors that meet the above conditions from the local peak identification matrix P according to the above screening conditions, the maximum number of column vectors with continuous column indexes (i.e., the difference between the column indices of two adjacent column vectors is 1) is counted based on the column indices corresponding to the selected column vectors in the local peak identification matrix P, and the maximum number of column vectors with continuous column indices is calculated as the maximum continuous channel number of local peak indexes corresponding to index c, and the maximum continuous channel number of local peak indexes is added to the array pn of the maximum continuous channel number of local peak indexes; by traversing the local peak index c represented by each element in the local peak index array pv, a local peak index maximum continuous channel number array pn can be obtained;

[0046] Step 8: Compare each element in the obtained local peak index maximum continuous channel number array with the maximum continuous channel number threshold to determine whether the original correlated single-shot seismic data of the controllable vibroseis source is a string induction interference shot;

[0047] Compare each element in the generated local peak index maximum continuous channel number array pn with the maximum continuous channel number threshold defined in step 4: if there is an element value in the maximum continuous channel number array pn that is greater than or equal to the maximum continuous channel number threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a string induction interference shot; if all element values ​​in the maximum continuous channel number array pn are less than the maximum continuous channel number threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a non-string induction interference shot. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0049] Figure 1 This is a flow chart of a serial sensing quality control method based on reverse correlation of scanning signals according to the present invention;

[0050] Figure 2 A schematic diagram of original correlated single-shot data of a vibroseis actually collected in the field in a specific embodiment of the present invention;

[0051] Figure 3 Schematic diagram of vibroseis scanning signals actually collected and applied in the field in a specific embodiment of the present invention, wherein (a) is the original vibroseis scanning signal sequence, and (b) is the reverse sequence of the vibroseis scanning signal sequence obtained by reversing the order of the original vibroseis scanning signal sequence;

[0052] Figure 4Schematic diagram of vibroseis secondary correlated single-shot seismic data obtained by cross-correlating original correlated single-shot seismic data of vibroseis with an inverse sequence of a scanning signal in a specific embodiment of the present invention;

[0053] Figure 5 A schematic diagram of seismic records corresponding to a standard trace matrix generated using vibroseis secondary correlation single-shot seismic data in a specific embodiment of the present invention;

[0054] Figure 6 A schematic diagram of a seismic record corresponding to a local peak identification matrix obtained by using a standard trace matrix to identify local peak symbols of vibroseis secondary correlation single shot seismic data in a specific embodiment of the present invention;

[0055] Figure 7 In a specific embodiment of the present invention, the local peak index array and the local peak index maximum continuous channel number array are generated by using the local peak matrix and the local peak identification matrix to form a local peak index and index maximum continuous channel number table. DETAILED DESCRIPTION

[0056] In order to make the above and other objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings.

[0057] like Figure 1 As shown, Figure 1 This is a flow chart of a string induction quality control method based on reverse correlation of scanning signals of the present invention. The string induction quality control method based on reverse correlation of scanning signals of the present invention first cross-correlates the inputted original correlated single shot data of the controllable source with the reverse sequence of the controllable source scanning signal to obtain the secondary correlated single shot data of the controllable source, and then calculates the average value of the seismic traces within a specified range near each secondary correlated single shot data to generate a standard trace matrix, and then uses the standard trace matrix to generate a local peak identification matrix and a local peak index array, and further obtains a local peak index maximum continuous trace number array, and finally determines whether the original correlated single shot seismic data of the controllable source is a string induction interference shot by comparing each element of the local peak index maximum continuous trace number array with the maximum continuous trace number threshold. It includes the following steps:

[0058] In step 1100, raw correlated single shot data of the controllable source and the controllable source scanning signal are input.

[0059] Input the original correlated single-shot seismic data matrix D of the vibroseis. D is expressed as follows:

[0060]

[0061] Where, d irepresents the i-th channel (column) data in the original correlated single-shot seismic data matrix D of the vibrator, d j'i Indicates the i-th channel (column) data d i The j'th sampling point in , n represents the number of channels (columns) of the original correlated single-shot seismic data matrix D of the vibrator, and m' represents the number of sampling points of each channel (column) of seismic data in the original correlated single-shot seismic data matrix D of the vibrator.

[0062] Input the vibrator scanning signal sequence sw, sw is expressed as follows:

[0063]

[0064] Where sw k' represents the k'th sampling point in the vibroseis scanning signal sequence sw, and n' represents the number of sampling points in the vibroseis scanning signal sequence sw. In practice, the number of sampling points n' in the vibroseis scanning signal sequence sw is greater than the number of sampling points m' per channel (column) of seismic data in the original correlated single-shot seismic data matrix D of the vibroseis, i.e., n'>m'.

[0065] In step 1200, the vibroseis scanning signal sequence is reversed to obtain an inverse sequence.

[0066] Reverse the order of the vibroseis scanning signal sequence sw to obtain the reverse sequence of the vibroseis scanning signal Then we have:

[0067] When k"+k'=n'+1, we have

[0068] Where, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points n' is the same as the number of sampling points of the vibrator scanning signal sequence sw.

[0069] In step 1300, the original correlated single shot data is cross-correlated with the inverse sequence of the scanning signal.

[0070] Each channel (column) of the input vibroseis original correlation single shot seismic data matrix D is respectively compared with the inverse sequence of the vibroseis scanning signal Perform a cross-correlation operation to obtain the secondary correlation seismic trace data for each channel (column). Then, sort the seismic trace data obtained after the secondary correlation operation of each channel (column) according to the channel (column) order corresponding to the controllable source original correlation single shot seismic data matrix D to form the controllable source secondary correlation single shot seismic data matrix X. The matrix X is expressed as follows:

[0071]

[0072] Where x i represents the i-th channel (column) data in the matrix X of the secondary correlation single shot seismic data of the vibrator, x ji Represents the i-th channel (column) data x i The j-th sampling point in , n represents the number of channels (columns) of the controllable source secondary correlation single shot seismic data matrix X, then the number of channels (columns) n is the same as the number of channels (columns) of the controllable source original correlation single shot seismic data matrix D, m represents the number of sampling points of each channel (column) of seismic data in the controllable source secondary correlation single shot seismic data matrix X, according to the relevant operation rules, it can be seen that m = m'+n'-1, where m' represents the number of sampling points of each channel (column) of seismic data in the controllable source original correlation single shot seismic data matrix D, and n' represents the inverse sequence of the controllable source scanning signal The number of sampling points.

[0073] The i-th channel (column) data d in the original correlated single-shot seismic data matrix D of the vibrator is i Inverse sequence with vibroseis scanning signal Perform cross-correlation operation to obtain the i-th channel (column) data x in the vibroseis secondary correlation single shot seismic data matrix X i The calculation formula is as follows:

[0074]

[0075] Where x ji represents the i-th channel (column) data x in the matrix X of the secondary correlation single shot seismic data of the vibrator i The jth sampling point in m represents the related single-channel seismic data x i The number of sampling points, Represents the correlation operator, d j'i represents the i-th channel (column) data d in the original correlated single-shot seismic data matrix D of the vibrator i The j'th sampling point in m' represents the original single-channel seismic data d i The number of sampling points, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points.

[0076] At step 1400, variables, arrays, and matrices for identifying string induction jammers are defined.

[0077] Define the following variables, arrays, or matrices for subsequent string induction jammer identification:

[0078] Define an empty local peak index array pv to store the index positions of subsequently identified local peaks.

[0079] An empty maximum continuous channel number array pn is defined to match the local peak index array pv, and is used to store the maximum continuous channel number corresponding to the index position of each local peak identified subsequently.

[0080] Define an m×n order local peak identification matrix P and initialize it to a zero matrix to store the local peak identification corresponding to each sampling point position of the vibroseis secondary correlation single shot seismic data matrix X. P is expressed as follows:

[0081]

[0082] Where p i Represents the local peak identification array of the ith channel (column) of the local peak identification matrix P, p ji Represents the local peak identification array p of the i-th channel (column) i The jth local peak identifier in the local peak identifier matrix P, n represents the number of channels (columns) in the local peak identifier matrix P (this number of channels (columns) is the same as the number of channels (columns) in the vibroseis secondary correlation single shot seismic data matrix X), and m represents the number of sampling points in the local peak identifier array for each channel (column) in the local peak identifier matrix P (this number of sampling points is the same as the number of sampling points in each channel (column) of the seismic data for the vibroseis secondary correlation single shot seismic data matrix X). In subsequent steps, local peaks will be screened out from the secondary correlation single shot data matrix X according to the specified conditions, and the sampling point values ​​at the corresponding positions in the local peak identifier matrix P will be reset based on the numerical signs (positive or negative) of these screened local peaks.

[0083] A maximum continuous channel number threshold is defined, and threshold is set to 10, which is used as the evaluation basis for determining whether the original correlated single-shot seismic data of the controllable source is a string induction interference shot.

[0084] In step 1500, the average value of the designated channel of the secondary correlation data is calculated to generate a standard channel matrix.

[0085] For each seismic data in the vibroseis secondary correlation single shot seismic data, the average value of the seismic traces within the adjacent specified trace index range is calculated and used as the standard trace corresponding to each secondary correlation data, thereby generating a standard trace matrix.

[0086] Calculate the standard trace corresponding to each trace (column) of the vibroseis secondary correlation single-shot seismic data matrix X with n traces. The calculation formula is as follows:

[0087]

[0088] In the formula, s i represents the standard trace corresponding to the i-th (column) data of the vibroseis secondary correlation single-shot seismic data matrix X, where 1 ≤ i ≤ n; p represents the starting trace (column) index for obtaining the standard trace s i : when i > 5, set p = i - 5, otherwise, set p = 1; q represents the ending trace (column) index for obtaining the standard trace s i : when i < n - 5, set q = i + 5, otherwise, set q = n; k represents the seismic trace index participating in the calculation of the standard trace s i , x jk represents the j-th sampling point in the k-th (column) data x i participating in the calculation of the standard trace s k , s ji represents the j-th sampling point of the standard trace s i , m represents the number of sampling points of the standard trace s i , and the number of sampling points m is the same as the number of sampling points of each trace (column) of the vibroseis secondary correlation single-shot seismic data matrix X;

[0089] After that, the obtained standard trace data of each trace are sorted in the same trace (column) order as the vibroseis secondary correlation single-shot seismic data matrix X to form the standard trace matrix S. The matrix S is represented as follows:

[0090]

[0091] In the formula, s i represents the standard trace data of the i-th (column) in the standard trace matrix S, s ji represents the j-th sampling point in the i-th (column) data s i , and n represents the number of traces (columns) of the standard trace matrix S, and the number of traces (columns) n is the same as the number of traces (columns) of the vibroseis secondary correlation single-shot seismic data matrix X.

[0092] In step 1600, a local peak identification matrix and an index array are generated using the standard trace matrix.

[0093] The local peaks in the vibroseis secondary correlation single-shot seismic data are identified using the generated standard trace matrix, and the local peak identification matrix is obtained by marking the numerical signs (positive or negative) of the local peaks. At the same time, the sampling point indices of the local peaks are recorded in the local peak index array.

[0094] Using the standard trace matrix S, all local peaks with the sampling point index l and trace index t that meet the requirements are screened out from the vibroseis secondary correlation single-shot seismic data matrix X according to the following conditions. The specific screening conditions are as follows:

[0095] 1) In the standard trace matrix S, the local peak value x in the matrix X of the secondary correlation single shot seismic data of the vibrator is lt Sampling point s with the same sampling point index l and track index t lt , should be the tth track (column) standard track data s t The sampling point with the largest absolute value from the ath to the bth sampling point. Where a is the larger value of t-20 / si and 1, b is the smaller value of t+20 / si and the number of sampling points m, and si is the sampling rate of the seismic data;

[0096] 2) In the matrix X of vibroseis secondary correlation single-shot seismic data, from the gth to the hth channel (column), the number of channels whose absolute value at the lth sampling point is greater than the absolute value of the sampling point before and after it 4 ms apart, divided by h-g+1, should be greater than 70%. Here, g is the larger of t-5 and 1, h is the smaller of t+5 and the number of channels (columns) n, and t is the channel index of the local peak.

[0097] 3) In the matrix X of the secondary correlation single shot seismic data of the vibroseis, the local peak x with sampling point index l and trace index t lt The absolute value of should be greater than the absolute value of the sampling point before and after it with an interval of 4ms in the same channel.

[0098] Then, in the matrix X of the secondary correlation single shot seismic data of the vibroseis, all local peaks x with sampling point index l and trace index t that meet the above conditions are selected. lt The numerical sign (positive or negative) of the local peak identification matrix P is used to identify each local peak identification sampling point p with the same sampling point index l and track index t. lt Reset the value of: If x lt is positive, let p lt =1; if x lt is negative, let p lt = -1. And add the sampling point index l corresponding to all local peaks to the local peak index array pv.

[0099] In step 1700, a peak index maximum continuous channel number array is generated using a local peak identification matrix.

[0100] The obtained local peak identification matrix is ​​used to count the maximum number of consecutive channels at each local peak index position to generate an array of the maximum number of consecutive channels of the local peak index.

[0101] For each local peak index c represented by each element value in the local peak index array pv, a column vector that meets the requirements is screened from the local peak identification matrix P according to the following conditions. The specific screening conditions are as follows:

[0102] 1) The absolute value of at least one of the c-1th, cth, and c+1th elements of this column vector must be 1;

[0103] 2) If the column index of this column vector in the local peak identification matrix P is greater than 1, then in the matrix P, the product of the c-th element value of the column vector and the c-th element value of the column vector in the adjacent previous column should be no less than 0, and when this product is equal to 0, the c-th element value of the column vector in the adjacent previous column should be equal to 0.

[0104] For each local peak index c represented by each element value in the local peak index array pv, after selecting column vectors that meet the above conditions from the local peak identification matrix P, the maximum number of column vectors with consecutive column indices (i.e., the difference between the column indices of two adjacent column vectors is 1) is calculated based on the column indices corresponding to the selected column vectors in the local peak identification matrix P. This is used as the maximum number of consecutive local peak indexes corresponding to index c and added to the local peak index maximum consecutive channel array pn. By traversing the local peak index c represented by each element in the local peak index array pv, a local peak index maximum consecutive channel array pn is obtained.

[0105] In step 1800, the local peak value is used to index the maximum continuous channel number array to identify the crosstalk jammer.

[0106] Each element in the obtained local peak index maximum continuous channel number array is compared with the maximum continuous channel number threshold to determine whether the original correlated single-shot seismic data of the controllable source is a string induction interference shot.

[0107] Each element in the generated local peak index maximum continuous channel number array pn is compared with the maximum continuous channel number threshold threshold defined in step 1400: if there is an element value in the maximum continuous channel number array pn that is greater than or equal to the maximum continuous channel number threshold threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a string induction interference shot; if all element values ​​in the maximum continuous channel number array pn are less than the maximum continuous channel number threshold threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a non-string induction interference shot.

[0108] The technical solution of the present invention is further described in detail below with reference to specific embodiments.

[0109] Step 1: Input the original relevant single shot data of the vibroseis collected during actual land exploration ( Figure 2 ), and the vibrator scanning signal used in construction ( Figure 3(a) The number of channels of the actual collected vibroseis raw correlation single-shot data is 8184, the record length is 6 seconds, the sampling rate is 2 ms, and the number of sampling points is 3001. Figure 2 The data shows a portion of the original single-shot data from the vibroseis, spanning from traces 7500 to 8000. This record contains a crosstalk signal, but its amplitude is not significantly different from that of other surrounding wavefields, making it difficult to identify. Figure 3 (a) shows the portion from the 6th to the 9th second of a linearly up-converted vibroseis sweep signal with a total length of 18 seconds, a sampling rate of 2ms, 9001 sampling points, and a frequency range of 1.5Hz to 120Hz in actual application;

[0110] Step 2: Reverse the order of the vibroseis scanning signal sequence used in the construction to obtain the inverse sequence of the vibroseis scanning signal ( Figure 3 (b)). Figure 3 (b) shows the 9th to 12th second portion of the reverse sequence of the vibrator scanning signal with a total length of 18 seconds, a sampling rate of 2ms, 9001 sampling points, and a frequency gradually decreasing from 120Hz to 1.5Hz. Since the total length of the vibrator scanning signal is 18 seconds, Figure 3 (a) shows the linear frequency rise of the original vibrator scanning signal from the 6th to the 9th second. Figure 3 (b) shows the portion from the 9th to the 12th second of the inverse sequence of the vibroseis scanning signal, which is a linear frequency-decreasing signal, and they are exactly a pair of inverse sequences.

[0111] Step 3: Cross-correlate each data in the original correlated single-shot seismic data of the controllable source with the inverse sequence of the controllable source scanning signal to obtain 8184 channels, 24 seconds of recording length, 2ms of sampling rate, and 12001 sampling points of the controllable source secondary correlated single-shot seismic data. Figure 4 The chart shows the recording section of the secondary correlation single shot seismic data with the number of traces ranging from 7500 to 8000 and the time range from 7 seconds to 13 seconds. Figure 2 The original correlation single shot data of the vibrator shown, Figure 4 In the vibroseis secondary correlation single-shot seismic data shown, string induction interference signals can be seen to a certain extent around 8 seconds, 8.5 seconds, 9.2 seconds, and 12.4 seconds. At this time, the string induction signals reappear in the data record as "pulse train group" characteristics;

[0112] Step 4, define an empty local peak index array pv; define an empty maximum continuous channel number array pn that matches the local peak index array pv; define a local peak identification matrix P with the same channel number and sampling point number as the vibrator secondary correlation single shot seismic data, and initialize the matrix to a zero matrix. According to the corresponding relationship with the vibrator secondary correlation single shot seismic data, the number of columns (channels) of matrix P is 8184, and the number of rows (sampling points) is 12001; define a maximum continuous channel number threshold threshold, and set threshold = 10. The variables, arrays or matrices defined above will be used for subsequent string induction interference shot identification;

[0113] Step 5: For each seismic data in the secondary correlation single-shot seismic data of the vibrator, calculate the average value of the data and the 5 adjacent data on the left and right (when there are less than 5 data on one side, take all the data on that side) as the standard track corresponding to this seismic data, and then form a standard track matrix with 8184 columns (tracks), a length of 24 seconds, a sampling rate of 2ms, and 12001 rows (sampling points). Figure 5 The sample rate of the seismic record is 2ms, showing the part of the standard trace matrix with the number of traces ranging from 7500 to 8000 and the time range from 7 seconds to 13 seconds. Figure 5 Each standard track data in Figure 4 Each seismic data in the displayed controlled source secondary correlation single shot seismic data corresponds one to one. Figure 4 , the string induction signals appearing at 8 seconds, 8.5 seconds, 9.2 seconds, and 12.4 seconds and showing the characteristics of "pulse train group" Figure 5 It is shown more clearly in

[0114] Step 6: Use the obtained standard trace matrix to identify the local peaks in the secondary correlation single shot seismic data of the vibroseis, and identify the signs of the local peaks to obtain the updated local peak identification matrix P. Figure 6 The symbols of the local peaks of the vibroseis secondary correlation single-shot seismic data with a sampling rate of 2ms are displayed in the form of seismic records with a sampling rate of 2ms. The symbols of the local peaks of each channel are in the range of 7500 to 8000 and the time range of 7 seconds to 13 seconds. The symbol samples of each channel with a positive local peak are set to 1, the symbol samples of the local peak with a negative local peak are set to -1, and the other symbol samples are set to 0. The updated local peak index array pv is obtained by recording the sampling point index of the local peak into an array. Figure 7 The table in the figure shows the local peak indexes and corresponding sampling times taken from the local peak index array pv within the two time ranges of 7 seconds to 10 seconds and 12.4 seconds to 12.5 seconds;

[0115] Step 7: By using the local peak identification matrix P, the maximum number of consecutive channels at each local peak index position is counted to obtain a set of local peak index maximum consecutive channel number arrays pn. Figure 7 The table shows the maximum number of consecutive channels corresponding to each local peak index in the two time periods from 7 seconds to 10 seconds and from 12.4 seconds to 12.5 seconds, taken from the local peak index maximum consecutive channel number array pn;

[0116] Step 8, compare the elements in the local peak index maximum continuous channel number array pn with the maximum continuous channel number threshold defined in step 4. Figure 7 The table shows that the maximum continuous trace counts at the local peak indices 3960 (7918ms), 3986 (7970ms), 4246 (8490ms), 4265 (8490ms), 4595 (9188ms), and 6206 (12410ms) are 25, 16, 29, 12, 10, and 56, respectively. The maximum continuous trace counts at these indexes are all no less than the threshold of 10, indicating the presence of crosstalk near these locations in the vibroseis secondary correlation single-shot seismic data. Consequently, the vibroseis raw correlation single-shot data currently undergoing quality control is determined to be a crosstalk interference shot.

[0117] The present invention fully considers the characteristic that the string induction signal presents a partial inverse sequence of the controllable source scanning signal in the original correlated single-shot data of the controllable source, and then cross-correlates the original correlated single-shot seismic data of the controllable source with the inverse sequence of the scanning signal, so that the string induction signal presents a pulse characteristic in the secondary correlated single-shot seismic data of the controllable source, and further highlights the difference between the string induction signal and other types of surrounding wave fields by establishing a standard trace, thereby realizing precise quality control of the string induction interference.

[0118] The advantages of the present invention are: (1) it overcomes the problem that the amplitude intensity of the string induction signal in the original correlated single-shot seismic data of the controllable source is not obviously different from that of other types of surrounding wave fields, and the problem that the controllable source scanning signal information contained in the original correlated single-shot seismic data of the controllable source is incomplete; (2) because this method uses the original correlated single-shot seismic data of the controllable source and the inverse sequence of the controllable source scanning signal to perform correlation operations, the string induction signal that presents some inverse sequence characteristics of the controllable source scanning signal in the original correlated single-shot seismic data of the controllable source is re-expressed as a pulse characteristic, which is conducive to the identification of string induction interference and further highlights the difference between the string induction signal and other types of surrounding wave fields by establishing a standard channel. Therefore, it can fully meet the field requirements for string induction quality control accuracy and achieve the purpose of improving indoor data processing effects.

[0119] The above embodiments are only used to illustrate the present invention, and the various implementation steps of the method can be changed. Any equivalent transformations and improvements based on the technical solution of the present invention should not be excluded from the scope of protection of the present invention.

Claims

1. A serial induction quality control method based on reverse correlation of seismic scanning signals, comprising the following steps: Step 1: Input the original correlated single-shot seismic data matrix D of the vibrator: Where, d i represents the i-th data in the original correlated single-shot seismic data matrix D of the vibrator, d j'i Indicates the i-th data d i The j'th sampling point in , n represents the number of channels of the original correlated single-shot seismic data matrix D of the vibrator, and m' represents the number of sampling points of each channel of seismic data in the original correlated single-shot seismic data matrix D of the vibrator; Input vibrator scanning signal sequence sw: Where sw k' represents the k'th sampling point in the vibrator scanning signal sequence sw, n' represents the number of sampling points in the vibrator scanning signal sequence sw, and in actual situations, n'>m'; Step 2: reverse the order of the vibroseis scanning signal sequence sw to obtain the reverse sequence of the vibroseis scanning signal Then we have: When k"+k'=n'+1, we have Where, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points n' is the same as the number of sampling points of the vibroseis scanning signal sequence sw; Step 3: Each data in the input vibroseis original correlation single shot seismic data matrix D is respectively compared with the inverse sequence of the vibroseis scanning signal Perform cross-correlation operations to obtain the data of each secondary correlation seismic trace. Then, sort the seismic trace data obtained after the secondary correlation operation according to the trace order corresponding to the controllable source original correlation single-shot seismic data matrix D to form the controllable source secondary correlation single-shot seismic data matrix X. The matrix X is expressed as follows: Where x i represents the i-th data in the matrix X of the secondary correlation single shot seismic data of the vibrator, x ji Represents the i-th data x i The jth sampling point in the matrix X is n, which is the number of channels in the matrix X of the secondary correlation single shot seismic data of the vibrator. Then the number n is the same as the number of channels in the matrix D of the original correlation single shot seismic data of the vibrator. m is the number of sampling points of each channel of seismic data in the matrix X of the secondary correlation single shot seismic data of the vibrator. According to the relevant operation rules, m = m' + n' - 1, where m' is the number of sampling points of each channel of seismic data in the matrix D of the original correlation single shot seismic data of the vibrator, and n' is the inverse sequence of the scanning signal of the vibrator. The number of sampling points; The i-th data d in the original correlated single-shot seismic data matrix D of the vibrator is i Inverse sequence with vibroseis scanning signal Perform cross-correlation operation to obtain the i-th data x in the vibroseis secondary correlation single shot seismic data matrix X i The calculation formula is as follows: Where x ji represents the i-th data x in the matrix X of the secondary correlation single shot seismic data of the vibrator i The jth sampling point in m represents the related single-channel seismic data x i The number of sampling points, Represents the correlation operator, d j'i represents the i-th data d in the original correlated single-shot seismic data matrix D of the vibrator i The j'th sampling point in m' represents the original single-channel seismic data d i The number of sampling points, Represents the inverse sequence of the vibroseis scanning signal The k'th sampling point in n' represents the reverse sequence of the vibroseis scanning signal The number of sampling points; Step 4: Define the following variables, arrays, or matrices for subsequent string induction jammer identification: Define an empty local peak index array pv to store the index positions of the subsequently identified local peaks; Define an empty maximum continuous channel number array pn that matches the local peak index array pv to store the maximum continuous channel number corresponding to the index position of each local peak identified subsequently; Define an m×n order local peak identification matrix P and initialize the matrix to a zero matrix to store the local peak identification corresponding to each sampling point position of the vibroseis secondary correlation single shot seismic data matrix X; P is expressed as follows: Where p i The local peak identification array of the local peak identification matrix P is represented by p ji Represents the local peak identification array p of the i-th channel i The j-th local peak identifier in the local peak identifier matrix P, n represents the number of channels in the local peak identifier matrix P, which is the same as the number of channels in the vibrator secondary correlation single shot seismic data matrix X, and m represents the number of sampling points in each local peak identifier array in the local peak identifier matrix P, which is the same as the number of sampling points in each seismic data in the vibrator secondary correlation single shot seismic data matrix X; in subsequent steps, local peaks will be screened out from the secondary correlation single shot data matrix X according to the specified conditions, and the sampling point values ​​at the corresponding positions in the local peak identifier matrix P will be reset according to the numerical signs of these screened local peaks; Define a maximum continuous channel number threshold, and set threshold = 10, as the evaluation basis for determining whether the original correlated single-shot seismic data of the controllable source is a string induction interference shot; Step 5: for each seismic data in the vibroseis secondary correlation single shot seismic data, calculate the average value of the seismic traces within the range of the adjacent specified trace index, and use it as the standard trace corresponding to each secondary correlation data, thereby generating a standard trace matrix; Calculate the standard trace corresponding to each data in the matrix X of the vibroseis secondary correlation single-shot seismic data with n traces. The calculation formula is as follows: Where s i represents the standard trace corresponding to the i-th trace data of the vibroseis secondary correlation single-shot seismic data matrix X, where 1 ≤ i ≤ n; p represents the starting trace index for obtaining the standard trace s i : when i > 5, set p = i - 5; otherwise, set p = 1; q represents the ending trace index for obtaining the standard trace s i : when i < n - 5, set q = i + 5; otherwise, set q = n; k represents the seismic trace index participating in the calculation of the standard trace s i , x jk represents the k-th trace data x participating in the calculation of the standard trace s i at the j-th sampling point, s k represents the j-th sampling point of the standard trace s ji , s i represents the j-th sampling point of the standard trace s i ; m represents the number of sampling points of the standard trace s. The number of sampling points m is the same as the number of sampling points of each seismic trace in the vibroseis secondary correlation single-shot seismic data matrix X. Afterwards, the obtained standard trace data are sorted in the same trace order as the vibroseis secondary correlation single-shot seismic data matrix X to form a standard trace matrix S. The matrix S is expressed as follows: Where s i represents the i-th standard track data in the standard track matrix S, s ji Indicates the i-th data s i The j-th sampling point in , n represents the number of channels in the standard channel matrix S, and the channel number n is the same as the channel number of the vibroseis secondary correlation single shot seismic data matrix X; Step 6: Use the generated standard trace matrix to identify the local peaks in the vibroseis secondary correlation single-shot seismic data, and obtain a local peak identification matrix by identifying the positive and negative numerical signs of the local peaks. At the same time, the sampling point index of the local peak is recorded in the local peak index array; Using the standard trace matrix S, all local peaks with sampling point index l and trace index t that meet the requirements are screened from the vibroseis secondary correlation single-shot seismic data matrix X according to the following conditions. The specific screening conditions are as follows: 1) In the standard trace matrix S, the local peak value x in the matrix X of the secondary correlation single shot seismic data of the vibrator is lt Sampling point s with the same sampling point index l and track index t lt , should be the t-th standard track data s t The sampling point with the largest absolute value from the ath to the bth sampling point in [1]. Where a is the larger value of t-20 / si and 1, b is the smaller value of t+20 / si and the number of sampling points m, and si is the sampling rate of the seismic data. 2) In the matrix X of vibroseis secondary correlation single-shot seismic data, from the gth to the hth data, the number of data channels whose absolute value of the lth sampling point is greater than the absolute value of the sampling point before and after it 4 ms apart, divided by h-g+1, should be greater than 70%; where g is the larger of t-5 and 1, h is the smaller of t+5 and the number of channels n, and t is the channel index of the local peak; 3) In the matrix X of the secondary correlation single shot seismic data of the vibroseis, the local peak x with sampling point index l and trace index t lt The absolute value of should be greater than the absolute value of the sampling point before and after it with a spacing of 4ms in the same channel; Then, in the matrix X of the secondary correlation single shot seismic data of the vibroseis, all local peaks x with sampling point index l and trace index t that meet the above conditions are selected. lt The sign of the value is positive or negative, for each local peak identification sampling point p with the same sampling point index l and channel index t in the local peak identification matrix P lt Reset the value of: If x lt is positive, let p lt =1; if x lt is negative, let p lt =-1; and add the sampling point index l corresponding to all local peaks to the local peak index array pv; Step 7, using the obtained local peak identification matrix, counting the maximum number of consecutive channels at each local peak index position, and generating a local peak index maximum consecutive channel number array; For each local peak index c represented by each element value in the local peak index array pv, a column vector that meets the requirements is screened from the local peak identification matrix P according to the following conditions. The specific screening conditions are as follows: 1) The absolute value of at least one of the c-1th, cth, and c+1th elements of this column vector must be 1; 2) If the column index of this column vector in the local peak identification matrix P is greater than 1, then in the matrix P, the product of the c-th element value of the column vector and the c-th element value of the column vector of the adjacent previous column should be no less than 0, and when this product is equal to 0, the c-th element value of the column vector of the adjacent previous column should be equal to 0; For each local peak index c represented by each element value in the local peak index array pv, after selecting the column vectors that meet the above conditions from the local peak identification matrix P according to the above screening conditions, the maximum number of column vectors with continuous column indexes is counted based on the column indexes corresponding to the selected column vectors in the local peak identification matrix P, and the maximum number of column vectors with continuous column indexes is used as the maximum continuous channel number of local peak indexes corresponding to index c, and the maximum continuous channel number of local peak indexes is added to the array pn of the maximum continuous channel number of local peak indexes; by traversing the local peak index c represented by each element in the local peak index array pv, a local peak index maximum continuous channel number array pn can be obtained; Step 8: Compare each element in the obtained local peak index maximum continuous channel number array with the maximum continuous channel number threshold to determine whether the original correlated single-shot seismic data of the controllable vibroseis source is a string induction interference shot; Compare each element in the generated local peak index maximum continuous channel number array pn with the maximum continuous channel number threshold defined in step 4: if there is an element value in the maximum continuous channel number array pn that is greater than or equal to the maximum continuous channel number threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a string induction interference shot; if all element values ​​in the maximum continuous channel number array pn are less than the maximum continuous channel number threshold, it can be determined that the original correlated single-shot seismic data of the controllable source is a non-string induction interference shot.

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