Abnormal interference gather detection method and system of common detection point gather

Abstract

The invention provides an abnormal interference gather detection method and system based on a common detection point gather, and belongs to the field of geophysical exploration seismic data acquisition and processing. According to the method, effective reflection energy and background noise are extracted based on a common detection point gather for data collected by a node instrument, and the quality of the common detection point gather is rapidly detected according to the effective reflection energy and the background noise. According to the invention, the quality of the common detection point gather can be rapidly detected, the reliability of acquired basic data is ensured, accurate basic data is provided for indoor processing, the working state of the node instrument can be controlled in real time, and a basis is provided for acquisition personnel to detect the node instrument in time.

Description

Technical Field

[0001] The invention belongs to the field of geophysical exploration seismic data acquisition and processing, and in particular relates to a method and system for detecting abnormal interference gathers of common detection point gathers. Background Art

[0002] The data collected by traditional cabled detectors can be transmitted back to the room in real time, and the indoor data quality control personnel can perform quality control checks on the collected data simultaneously. The data collected by the cabled detectors are in complete single-shot form.

[0003] In recent years, node detectors (also known as node instruments) have been gradually used to replace cable detectors. The data collected by node detectors are stored inside the node instruments. The node instruments need to be recovered indoors, and the data can be quality controlled after downloading and cutting. In addition, when recovering node instruments, only node instruments whose collection tasks have been completed can be recovered. Node instruments that need to be used continuously cannot be recovered. This results in that the data recovered in the early stage cannot be synthesized into a complete single shot. For node instruments, it is more appropriate to recover data in the form of detection lines. Therefore, when checking data quality control, it cannot be done in the traditional single shot form. It is necessary to perform data quality control checks on the common detection point gathers. At the same time, because the node instrument cannot control the working status in real time, factors such as abnormal operation of the node instrument will cause abnormal reception of data, that is, abnormal interference in the received data, so it is very necessary to perform quality control on the data collected by the node instrument to ensure the reliability of the collected basic data and provide accurate basic data for indoor processing. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art and to provide a method and system for detecting abnormal interference gathers of common detection point gathers, which can quickly detect the quality of common detection point gathers, ensure the reliability of basic data collection, provide accurate basic data for indoor processing, and at the same time can real-time quality control the working status of node instruments, providing a basis for collection personnel to timely detect node instruments.

[0005] The present invention is achieved through the following technical solutions:

[0006] The first aspect of the present invention provides a method for detecting abnormal interference gathers of common detection point gathers, which extracts effective reflection energy and background noise based on the common detection point gathers for data collected by the node instrument, and quickly detects the quality of the common detection point gathers based on the effective reflection energy and background noise.

[0007] Preferably, the method comprises:

[0008] (1) Input the data collected by the node instrument and extract the common detection point gather records;

[0009] (2) Leveling the common detection point gathers to obtain leveled common detection point gathers;

[0010] (3) Selecting a time window;

[0011] (4) extracting the absolute amplitude value of each trace in each time window;

[0012] (5) Obtain the average absolute amplitude value of the common detection point gathers in each time window;

[0013] (6) Obtaining the abnormal interference development index T2;

[0014] (7) Determine the abnormal detection point.

[0015] Preferably, the operation of step (2) includes:

[0016] The common detection point gathers are leveled by formula (1), and the first arrivals are corrected to the position of the leveling reference surface:

[0017] St=Q-(1 / V0)*D 0ff *1000 (1)

[0018] Where St is the correction amount for each pass; Q is the leveling reference surface; V0 is the replacement speed of the work area, in m / s; D 0ff It is the absolute value of the offset of each trace, in m.

[0019] Preferably, the value range of Q is 600-2000ms.

[0020] Preferably, the operation of step (3) includes:

[0021] On the leveled common detection point gathers, two time windows are selected, namely the time window above the first arrival and the time window below the first arrival.

[0022] Preferably, the operation of step (4) includes:

[0023] The absolute amplitude value of each trace in the time window above the first arrival and the time window below the first arrival is obtained respectively.

[0024] Preferably, the operation of step (5) includes:

[0025] The absolute amplitude values ​​of all traces in the time window above the first arrival are added together and then divided by the number of traces to obtain the average absolute amplitude value in the time window above the first arrival;

[0026] The absolute amplitude values ​​of all channels in the time window below the first arrival are added together and divided by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival.

[0027] Preferably, the operation of step (6) includes:

[0028] The average absolute amplitude value in the time window below the first arrival is taken as the effective reflection energy, and the average absolute amplitude value in the time window above the first arrival is taken as the background noise. The effective reflection energy is divided by the background noise to obtain the abnormal interference development index T2.

[0029] Preferably, the operation of step (7) includes:

[0030] A threshold value of T2 is set. If T2 of a detection point is less than or equal to the threshold value, the detection point is determined to be an abnormal detection point.

[0031] A second aspect of the present invention provides a common detection point gather abnormal interference gather detection system, the system comprising:

[0032] Input module: used to input the data collected by the node instrument and extract the common detection point gather records;

[0033] Leveling module: used to level the common detection point gathers by formula (1) and correct the first arrival to the position of the leveling reference surface:

[0034] St=Q-(1 / V0)*D 0ff *1000 (1)

[0035] Where St is the correction amount for each pass; Q is the leveling reference surface; V0 is the replacement speed of the work area, in m / s; D 0ff is the absolute value of the offset of each trace, in m;

[0036] Time window selection module: used to select two time windows on the leveled common detection point gathers, namely the time window above the first arrival and the time window below the first arrival;

[0037] Extracting absolute amplitude value module: used to obtain the absolute amplitude value of each channel in the time window above the first arrival and the time window below the first arrival respectively;

[0038] Averaging module: It is used to add up the absolute amplitude values ​​of all channels in the time window above the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window above the first arrival; it is used to add up the absolute amplitude values ​​of all channels in the time window below the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival;

[0039] The module for obtaining the abnormal interference development index is used to take the average absolute amplitude value in the time window below the first arrival as the effective reflection energy, the average absolute amplitude value in the time window above the first arrival as the background noise, and divide the effective reflection energy by the background noise to obtain the abnormal interference development index T2;

[0040] Judgment module: used to set the threshold value of T2. If the T2 of a detection point is less than or equal to the threshold value, the detection point is judged as an abnormal detection point.

[0041] Compared with the prior art, the beneficial effects of the present invention are: the quality of the common detection point gather can be quickly detected by the present invention, the reliability of the basic data collection can be ensured, and accurate basic data can be provided for indoor processing. At the same time, the working status of the node instrument can be quality controlled in real time, providing a basis for the collection personnel to detect the node instrument in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Common detection point gather records (sorted by shot time sequence);

[0043] Figure 2 Common geophone gathers after leveling;

[0044] Figure 3 Two time windows of the common detector gather after leveling;

[0045] Figure 4 The average absolute amplitude value of each trace is obtained;

[0046] Figure 5 Abnormal common detection point gathers with T2 value of 1;

[0047] Figure 6 Abnormal common detection point gathers with T2 value of 1;

[0048] Figure 7 Abnormal common detector gathers with T2 value of 1.2;

[0049] Figure 8 Abnormal common detection point gather distribution map;

[0050] Fig. 9 A flowchart of the steps of the method of the present invention. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0052] The present invention provides a method for detecting abnormal interference gathers of common detection point gathers. The method extracts effective reflection energy and background noise respectively based on the common detection point gathers for the data collected by the node instrument, and quickly detects the quality of the common detection point gathers according to the effective reflection energy and the background noise, thereby ensuring the reliability of the collected basic data and providing accurate basic data for indoor processing. At the same time, the method can quality control the working status of the node instrument in real time, and provide a basis for the collection personnel to detect the node instrument in time.

[0053] like Fig. 9 As shown, the embodiments of the method of the present invention are as follows:

[0054] Embodiment 1:

[0055] The method comprises:

[0056] (1) Input the data collected by the node instrument and extract the common detection point gather records:

[0057] In order to control the working status of each node instrument (a node instrument corresponds to a detection point one by one, and a node instrument is a detection point) and to perform abnormal interference statistics on the common detection point gather, it is first necessary to extract the data into common detection point gather records (the existing method can be used for extraction, which will not be repeated here). The extracted common detection point gather records are as follows: Figure 1 As shown, Figure 1 The CCP geophone point gathers are sorted according to the chronological order of the shots.

[0058] (2) Level the common detection point gathers to obtain the leveled common detection point gathers:

[0059] The common detection point gathers are leveled, and the first arrivals are corrected to the position of the leveling reference plane to obtain the leveled common detection point gathers, such as Figure 2 As shown, it is convenient to open the time window for energy statistics.

[0060] Specifically, the common detection point gathers are leveled by formula (1), and the first arrivals are corrected to the position of the leveling reference surface:

[0061] St=Q-(1 / V0)*D 0ff *1000 (1)

[0062] Where St is the correction amount for each trace; V0 is the replacement velocity of the work area (a basic concept in seismic data processing, a constant. There is only one replacement velocity for a work area, which can be given based on experience or the linear velocity of the first arrival can be used as the replacement velocity), in units of m / s; D 0ff is the absolute value of the offset of each trace (which comes with the collected data and can be directly read from the collected data), in meters; Q is the leveling reference surface. In order to ensure that the time window above the first arrival is large enough, the leveling reference surface Q should not be too small. It is not necessary to be too large. It can be given according to actual data. Generally speaking, the value range of the leveling reference surface Q is 600-2000ms, preferably 800ms;

[0063] (3) Select time window

[0064] On the leveled common detection point gather, two time windows are selected, namely the time window above the first arrival and the time window below the first arrival. The first arrival is at the leveling reference plane, for example 800ms, so the time window above the first arrival can be selected from 0-750ms to avoid the data below the first arrival. The normal detection point is the background noise segment with weak energy, such as Figure 3 The time window below the first arrival is 800-1550ms, as shown in the solid line box above. Figure 3As shown in the dotted box below, select the position of the effective reflection segment below the first arrival. The energy of this segment at the normal detection point is relatively strong, which is the effective reflection energy segment. Usually, the time window length below the first arrival is determined based on the time window length above the first arrival to ensure that the two time windows are the same length. If a length of 0-750ms is selected above the first arrival, then a time window length of 750ms is also selected below the first arrival. If the first arrival reference plane is selected as 1000ms, and the time window length above the first arrival is 900ms, then the time window length below the first arrival is also selected as 900ms.

[0065] (4) Extract the absolute amplitude value of each channel in each time window

[0066] exist Figure 3 In the given two time windows, the absolute amplitude value of each trace in the time window above the first arrival and the time window below the first arrival is calculated. Figure 4 As shown, Figure 4 The upper middle curve is the absolute amplitude value of each track in the time window above the first arrival, and the middle curve is the absolute amplitude value of each track in the time window below the first arrival (the absolute amplitude value is obtained using the existing method, which will not be repeated here).

[0067] (5) Obtain the average absolute amplitude of the common detection point gathers in each time window

[0068] After obtaining the absolute amplitude value of each channel in step (4), the average absolute amplitude value of all channels in each time window is calculated. That is, the absolute amplitude values ​​of all channels in the time window above the first arrival are added together and divided by the number of channels to obtain the average absolute amplitude value in the time window above the first arrival; the absolute amplitude values ​​of all channels in the time window below the first arrival are added together and divided by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival.

[0069] (6) Obtaining the abnormal interference development index T2

[0070] The average absolute amplitude value in the time window below the first arrival is taken as the effective reflection energy, and the average absolute amplitude value in the time window above the first arrival is taken as the background noise. The effective reflection energy is divided by the background noise to obtain the abnormal interference development index T2;

[0071] (7) Determine the abnormal detection point:

[0072] A threshold value of T2 is set. If T2 of a detection point is less than or equal to the threshold value, the detection point is determined to be an abnormal detection point.

[0073] For example, if the threshold value is 1, when T2 is less than or equal to 1, it means that the energy below the first arrival is smaller than the energy above the first arrival, and the abnormal interference of the common detection point gather is relatively developed, that is, the detection point is an abnormal detection point, and the working status of the node instrument needs to be checked.

[0074] Through the calculation in step (6), we can get Figure 1 The T2 value of the receiver gather in the above figure is 8, which means that the energy below the first arrival is 8 times that above the first arrival (from Figure 1 It can also be seen that the effective reflection energy is significantly stronger than the background noise energy). By calculation, we get Figure 5 The T2 value of the common detection point gather in the Figure 5 It can also be seen in the figure that the background noise is consistent with the effective reflected energy), and the energy above the first arrival is the same as the energy below the first arrival.

[0075] Figure 6 and Figure 7 The abnormal interference common detection point gathers obtained by using the method of the present invention are given respectively. Figure 6 The amplitude value of each sample point in the common detection point gather is the same, which is caused by the abnormal operation of the node instrument. Figure 7 is the common receiver gather developed with background interference ( Figure 7 The curve in the upper middle part is the offset curve, which is close to the first arrival position. The approximate position of the first arrival can be determined by this curve. The background noise is above the curve, which is obviously not clean and has strong energy), indicating that the node instrument is located in an area with severe environmental interference.

[0076] Figure 8 is the abnormal detection point position distribution diagram of each detection point gather obtained by the method of the present invention, Figure 8 Each small dot in represents a detection point. If the T2 value of a detection point is greater than the threshold value, the detection point is a detection point with low abnormal interference, represented by a triangle; if the T2 value of a detection point is less than or equal to the threshold value, the detection point is a detection point with strong abnormal interference, that is, an abnormal detection point, represented by a circle. Figure 8 The distribution diagram of all detection points after the threshold value is set is displayed. For abnormal detection points, the equipment and acquisition environment at these locations need to be checked in detail.

[0077] The present invention also provides a common detection point gather abnormal interference gather detection system, and the embodiments of the system are as follows:

[0078] Embodiment 2:

[0079] The system comprises:

[0080] Input module: used to input the data collected by the node instrument and extract the common detection point gather records;

[0081] Leveling module: used to level the common detection point gathers by formula (1) and correct the first arrival to the position of the leveling reference surface:

[0082] St=Q-(1 / V0)*D 0ff*1000 (1)

[0083] Where St is the correction amount for each pass; Q is the leveling reference surface; V0 is the replacement speed of the work area, in m / s; D 0ff It is the absolute value of the offset of each trace, in m.

[0084] Time window selection module: used to select two time windows on the leveled common detection point gathers, namely the time window above the first arrival and the time window below the first arrival;

[0085] Extracting absolute amplitude value module: used to obtain the absolute amplitude value of each channel in the time window above the first arrival and the time window below the first arrival respectively;

[0086] Averaging module: It is used to add up the absolute amplitude values ​​of all channels in the time window above the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window above the first arrival; it is used to add up the absolute amplitude values ​​of all channels in the time window below the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival;

[0087] The module for obtaining the abnormal interference development index is used to take the average absolute amplitude value in the time window below the first arrival as the effective reflection energy, the average absolute amplitude value in the time window above the first arrival as the background noise, and divide the effective reflection energy by the background noise to obtain the abnormal interference development index T2;

[0088] Judgment module: used to set the threshold value of T2. If the T2 of a detection point is less than or equal to the threshold value, the detection point is judged as an abnormal detection point.

[0089] The present invention relates to a data quality inspection technology based on a common detection point gather for node instrument data collection, which can be applied to node instrument data collection inspection and quality control and similar detector data collection inspection and quality control. The present invention mainly extracts background noise and effective reflection energy respectively through a common detection point gather, compares the two energies, sets a threshold value, and quickly detects the quality of the common detection point gather, thereby ensuring the reliability of the collected basic data and providing accurate basic data for indoor processing. At the same time, it can quality control the working status of the node instrument in real time, providing a basis for the collection personnel to adjust the node instrument in time.

[0090] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0091] In the description of the present invention, unless otherwise specified, the terms "upper", "lower", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0092] The above technical solution is only one implementation mode of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical solution described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. A method for detecting abnormal interference gathers of common detection point gathers, characterized by: The method extracts effective reflection energy and background noise respectively based on the common detection point gathers for the data collected by the node instrument, and quickly detects the quality of the common detection point gathers according to the effective reflection energy and the background noise.

2. The abnormal interference gather detection method of common detection point gather according to claim 1, characterized in that: The method comprises: (1) Input the data collected by the node instrument and extract the common detection point gather records; (2) Leveling the common detection point gathers to obtain leveled common detection point gathers; (3) Selecting a time window; (4) extracting the absolute amplitude value of each trace in each time window; (5) Obtain the average absolute amplitude value of the common detection point gathers in each time window; (6) Obtaining the abnormal interference development index T2; (7) Determine the abnormal detection point.

3. The abnormal interference gather detection method of common detection point gathers according to claim 2, characterized in that: The operation of step (2) includes: The common detection point gathers are leveled by formula (1), and the first arrivals are corrected to the position of the leveling reference surface: St=Q-(1 / V0)*D 0ff *1000 (1) Where St is the correction amount for each pass; Q is the leveling reference surface; V0 is the replacement speed of the work area; D 0ff is the absolute value of the offset of each trace.

4. The abnormal interference gather detection method of common detection point gathers according to claim 3 is characterized in that: The value range of Q is 600-2000ms.

5. The abnormal interference gather detection method of common detection point gathers according to claim 2, characterized in that: The operation of step (3) includes: On the leveled common detection point gathers, two time windows are selected, namely the time window above the first arrival and the time window below the first arrival.

6. The abnormal interference gather detection method of common detection point gathers according to claim 5, characterized in that: The operation of step (4) includes: The absolute amplitude value of each trace in the time window above the first arrival and the time window below the first arrival is obtained respectively.

7. The abnormal interference gather detection method of common detection point gathers according to claim 6, characterized in that: The operation of step (5) includes: The absolute amplitude values ​​of all traces in the time window above the first arrival are added together and then divided by the number of traces to obtain the average absolute amplitude value in the time window above the first arrival; The absolute amplitude values ​​of all channels in the time window below the first arrival are added together and divided by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival.

8. The abnormal interference gather detection method of common detection point gathers according to claim 7, characterized in that: The operation of step (6) includes: The average absolute amplitude value in the time window below the first arrival is taken as the effective reflection energy, and the average absolute amplitude value in the time window above the first arrival is taken as the background noise. The effective reflection energy is divided by the background noise to obtain the abnormal interference development index T2.

9. The abnormal interference gather detection method of common detection point gathers according to claim 8, characterized in that: The operation of step (7) includes: A threshold value of T2 is set. If T2 of a detection point is less than or equal to the threshold value, the detection point is determined to be an abnormal detection point.

10. A system for detecting abnormal interference gathers of common detection point gathers, characterized in that: The system comprises: Input module: used to input the data collected by the node instrument and extract the common detection point gather records; Leveling module: used to level the common detection point gathers by formula (1) and correct the first arrival to the position of the leveling reference surface: St=Q-(1 / V0)*D 0ff *1000 (1) Where St is the correction amount for each pass; Q is the leveling reference surface; V0 is the replacement speed of the work area; D 0ff is the absolute value of the offset of each trace; Time window selection module: used to select two time windows on the leveled common detection point gathers, namely the time window above the first arrival and the time window below the first arrival; Extracting absolute amplitude value module: used to obtain the absolute amplitude value of each channel in the time window above the first arrival and the time window below the first arrival respectively; Averaging module: It is used to add up the absolute amplitude values ​​of all channels in the time window above the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window above the first arrival; it is used to add up the absolute amplitude values ​​of all channels in the time window below the first arrival and divide by the number of channels to obtain the average absolute amplitude value in the time window below the first arrival; The module for obtaining the abnormal interference development index is used to take the average absolute amplitude value in the time window below the first arrival as the effective reflection energy, the average absolute amplitude value in the time window above the first arrival as the background noise, and divide the effective reflection energy by the background noise to obtain the abnormal interference development index T2; Judgment module: used to set the threshold value of T2. If the T2 of a detection point is less than or equal to the threshold value, the detection point is judged as an abnormal detection point.

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