Method for identifying ghost wave in hydrographic data

Abstract

The present application belongs to the technical field of petroleum seismic exploration data analysis, and discloses a method for identifying ghost waves in water-land dual detection data. The method is to extract odd and even sequences from the water-land dual detection data respectively, and then to obtain rearranged staggered display water-land detection primary wave data and staggered display water-land detection ghost wave data through phase twisting. Then, the continuity and consistency of the same phase axis of the rearranged data are identified to distinguish the primary wave and the ghost wave. In the technical field of petroleum seismic exploration data analysis, the ghost wave with interference effect can be intuitively distinguished, which is used to guide the dual detection synthesis processing, facilitate the subsequent dual detection synthesis processing, and improve the efficiency of seismic data acquisition and analysis.

Description

Technical Field

[0001] This invention belongs to the field of petroleum seismic exploration data analysis technology, and relates to a method for identifying ghost waves, specifically a method for identifying ghost waves in land and water dual-detection data. Background Technology

[0002] Today, offshore oil and gas field exploration and development has entered the stage of exploring deep, complex structural, and lithological oil and gas reservoirs, placing increasingly higher demands on seismic data. Submarine multi-component seismic data offers advantages such as receiving multiple data components, wide azimuth, low noise, broadband frequency, and multiple measurements, leading to its increasing application in fine-grained exploration and reservoir monitoring in oil and gas fields. In recent years, submarine cable (OBC) and submarine node (OBN) seismic technologies have developed rapidly and are considered a trend in offshore seismic development. In particular, the development of rope-tethered OBN construction technology in shallow waters has significantly reduced construction costs.

[0003] Because submarine cables and nodes containing both pressure and velocity detectors are laid directly on the seabed, they inevitably receive multiple waves from the water layer between the sea level and the seabed. These multiple waves are also known as ghost waves. The primary waves, which are the effective data to be recorded in seismic exploration, are often interfered with by ghost waves. The frequency trapping phenomenon and low-frequency energy loss caused by ghost waves affect the resolution of both land and sea detector data and reduce the effective bandwidth of the seismic signal, which greatly limits the quality of seismic exploration.

[0004] For a long time, primary and secondary waves have been indistinguishable due to their overlapping and overlapping nature. Even rough identification of ghost waves has faced technical challenges. Typically, the presence of ghost waves can only be confirmed by the spectral notch points in the dual-surface and land-water monitoring data, rather than by identifying primary and secondary waves as a whole on the profile. Therefore, how to intuitively identify primary and ghost waves in dual-surface and land-water monitoring data has always been a major challenge for the industry. Summary of the Invention

[0005] The purpose of this invention is to provide a method for identifying ghost waves in land and water dual-inspection data. This method rearranges the data by extracting odd and even sequences from the land and water dual-inspection data and displaying them alternately and by twisting the phase. Then, by identifying the continuity and consistency of the in-phase axis of the rearranged data, the method can distinguish between primary waves and ghost waves.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for identifying ghost waves in land and water dual-detection data, comprising the following steps performed sequentially:

[0008] S1. Extracting the odd / even sequence

[0009] The odd-numbered sequence data of water inspection single guns are extracted sequentially according to the keyword number to obtain the odd-numbered sequence data of water inspection single guns.

[0010] That is, extract the water inspection single-shot data with the keyword numbers 1, 3, 5, 7, 9... in sequence, keep the arrangement order unchanged, and arrange them in order to obtain the odd sequence data of water inspection single-shot;

[0011] The land inspection single-gun data are extracted sequentially according to the keyword number to obtain the land inspection single-gun even sequence data;

[0012] That is, extract the land inspection single gun data with the key numbers 2, 4, 6, 8, 10... in sequence, keep the arrangement order unchanged, and arrange them in order to obtain the land inspection single gun even number sequence data;

[0013] Specifically, the odd-numbered sequence data of single-gun inspections on water and the even-numbered sequence data of single-gun inspections on land are arranged sequentially according to their keyword numbers to obtain interleaved display of the original water and land inspection data; that is, the interleaved display order of the original water and land inspection data is: water inspection single-gun data with keyword number 1, land inspection single-gun data with keyword number 2, water inspection single-gun data with keyword number 3, land inspection single-gun data with keyword number 4, land inspection single-gun data with keyword number 5, water inspection single-gun data with keyword number 6, and so on...

[0014] S2. Phase Twist

[0015] The odd-number sequence data of single-shot water-based detectors are rotated by 90° to obtain 90° odd-number data of single-shot water-based detectors.

[0016] Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne primary wave data by sequentially arranging them according to the keyword number;

[0017] The odd-numbered data of a single shot from a 90° water-based detector are rotated by 180° to obtain the odd-numbered data of a single shot from a 180° water-based detector.

[0018] Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne ghost wave data by sequentially arranging them according to the keyword number.

[0019] S3. Identify Ghost Waves

[0020] The continuity and consistency of the in-phase axis of the interleaved display of primary wave data from land and water detection and the interleaved display of ghost wave data from land and water detection were identified respectively; among them,

[0021] In the interleaved display of primary wave data from land and water inspections, those with poor continuity and consistency of the same phase axis are ghost waves, while those with good continuity and consistency of the same phase axis are primary waves.

[0022] In the interleaved display of land and water ghost wave data, those with good continuity and consistency of the same phase axis are ghost waves, while those with poor continuity and consistency of the same phase axis are primary waves.

[0023] The key number is the gun number, track number, line number, or common center point number.

[0024] As is known to those skilled in the art, the shot number, track number, line number, and common center point number refer to the shot station number, seismic track number, main survey line number, connecting survey line number, and common center point number.

[0025] This invention also provides a method for identifying ghost waves in dual-surface and land-based inspection data. This method involves extracting even-numbered keywords from single-surface inspection data and odd-numbered keywords from single-surface inspection data during step S1. Specifically, the method includes the following steps performed sequentially:

[0026] S01. Extracting the odd / even sequence

[0027] The even-numbered keyword data of the single water gun is extracted sequentially according to the keyword number to obtain the even-numbered sequence data of the single water gun.

[0028] The odd-numbered sequence data of land-based single-gun inspections are extracted sequentially according to the keyword number to obtain the odd-numbered sequence data of land-based single-gun inspections.

[0029] Among them, the odd-numbered sequence data of single guns for land inspection and the even-numbered sequence data of single guns for water inspection are arranged in order of keyword number to obtain the original data of land and water inspections in an alternating manner.

[0030] S02. Phase Twist

[0031] The even-number sequence data of single-shot water-based detectors are rotated by 90° to obtain 90° even-number data of single-shot water-based detectors.

[0032] Arrange the even-numbered data of single-shot waterborne and odd-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne primary wave data by sequentially arranging them according to the keyword number;

[0033] The 90° water-based single-shot even data is rotated by 180° phase to obtain the 180° water-based single-shot even data.

[0034] Arrange the even-numbered data of single-shot waterborne and odd-numbered sequence data of single-shot landborne waterborne and landborne waterborne ghost wave data by sequentially arranging them according to the keyword number.

[0035] S03. Identify ghost waves

[0036] The continuity and consistency of the in-phase axis of the interleaved display of primary wave data from land and water detection and the interleaved display of ghost wave data from land and water detection were identified respectively; among them,

[0037] In the interleaved display of primary wave data from land and water inspections, those with poor continuity and consistency of the same phase axis are ghost waves, while those with good continuity and consistency of the same phase axis are primary waves.

[0038] In the interleaved display of land and water ghost wave data, those with good continuity and consistency of the same phase axis are ghost waves, while those with poor continuity and consistency of the same phase axis are primary waves.

[0039] The key number is the gun number, track number, line number, or common center point number.

[0040] By adopting the above-mentioned technical solution, the technical progress achieved by this invention compared with the prior art is as follows:

[0041] This invention can intuitively identify primary waves and ghost waves in land and water detection based on the continuity and consistency of the data. In the interleaved display of primary wave data for land and water detection, those with poor continuity and consistency of the phase axis are ghost waves, while those with good continuity and consistency of the phase axis are primary waves. In the interleaved display of ghost wave data for land and water detection, those with good continuity and consistency of the phase axis are ghost waves, while those with poor continuity and consistency of the phase axis are primary waves.

[0042] This invention can be used to guide dual-inspection synthesis processing, wherein the interleaved display of the original land and water inspection data shows that the single gun launches are harmonious and consistent, which facilitates subsequent dual-inspection synthesis processing.

[0043] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0044] Figure 1 This is a cross-sectional view showing the interleaved display of raw water and land inspection data in an embodiment of the present invention;

[0045] Figure 2 This is a cross-sectional view showing the interleaved display of primary wave data from land and water surveys in an embodiment of the present invention;

[0046] Figure 3 This is a cross-sectional view of the interleaved display of ghost wave data from land and water detection in an embodiment of the present invention;

[0047] In the diagram: 1 - upper part, 2 - lower part. Detailed Implementation

[0048] Example: A method for identifying ghost waves in land and water dual-detection data.

[0049] This embodiment performs ghost wave identification on water and land survey data collected from submarine cables containing pressure and velocity detectors. The specific method includes the following steps performed sequentially:

[0050] S1. Extracting the odd / even sequence

[0051] The water inspection single shot data with track numbers 1, 3, 5, 7, and 9 are extracted in ascending order, and the sorting order is kept unchanged. This process is repeated to obtain the odd sequence data of water inspection single shot.

[0052] The land-based single-gun data with track numbers 2, 4, 6, 8, and 10 are extracted in ascending order of track number, and the order is kept unchanged. This process is repeated to obtain the even-numbered sequence of land-based single-gun data.

[0053] The odd-numbered sequence data of single-gun inspections on water and the even-numbered sequence data of single-gun inspections on land are arranged in ascending order according to the track number as follows: Track 1 (water inspection single-gun data), Track 2 (land inspection single-gun data), Track 3 (water inspection single-gun data), Track 4 (land inspection single-gun data), Track 5 (water inspection single-gun data), Track 6 (land inspection single-gun data), Track 7 (water inspection single-gun data), Track 8 (land inspection single-gun data), Track 9 (water inspection single-gun data), and Track 10 (land inspection single-gun data). The above 10 data are the original water and land inspection data displayed in an alternating manner.

[0054] The interleaved raw data of land and water inspections is displayed on the screen, resulting in an interleaved cross-sectional view of the raw data, such as... Figure 1 The initial arrival and start-up are relatively consistent and have good continuity, which facilitates subsequent dual-detection synthesis processing. At the same time, taking the period between 500 ms and 600 ms as an example, it can be seen that the in-phase axes intersect each other between 500 ms and 600 ms, indicating that there is a phase difference between the primary wave and the ghost wave. The results at other positions are similar.

[0055] S2. Phase Twist

[0056] The odd-number sequence data of single-shot water-based detectors are rotated by 90° to obtain 90° odd-number data of single-shot water-based detectors.

[0057] Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne primary wave data by sequentially arranging them according to the keyword number;

[0058] The odd-numbered data of a single shot from a 90° water-based detector are rotated by 180° to obtain the odd-numbered data of a single shot from a 180° water-based detector.

[0059] Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne ghost wave data by sequentially arranging them according to the keyword number.

[0060] S3. Identify Ghost Waves

[0061] The screen displays a cross-sectional view, which is used to identify the continuity and consistency of the phase axis of the interleaved display of primary wave data and ghost wave data of water and land detection.

[0062] Among them, the cross-sectional view of primary wave data from both land and water is displayed alternately, such as... Figure 2Taking the period between 500 milliseconds and 600 milliseconds as an example, in the upper part of the period between 500 milliseconds and 600 milliseconds, the continuity and consistency of the in-phase axis are good, which is the primary wave; in the lower part of the period between 500 milliseconds and 600 milliseconds, the continuity and consistency of the in-phase axis are poor, which is the ghost wave, and the other positions are similar.

[0063] Interleaved display of water and land ghost wave data profile diagrams, such as Figure 3 Taking the period between 500 milliseconds and 600 milliseconds as an example, in the lower part of the period between 500 milliseconds and 600 milliseconds, the continuity and consistency of the in-phase axis are good, which is a ghost wave; in the upper part of the period between 500 milliseconds and 600 milliseconds, the continuity and consistency of the in-phase axis are poor, which is a primary wave, and the other positions are similar.

[0064] In this embodiment, the primary wave and ghost wave in the water and land inspection data can be intuitively identified by interleaving the cross-sectional view of the primary wave data and the cross-sectional view of the ghost wave data.

[0065] In addition, in S1. when extracting the odd and even number sequence, even-numbered keyword numbers are extracted from the water inspection single-shot data, and odd-numbered keyword numbers are extracted from the land inspection single-shot data. The other steps are basically the same as those in the above embodiment, except that the extracted keyword numbers are adjusted to be odd or even, which also yields the result of intuitively identifying the primary wave and ghost wave in the water and land inspection data.

[0066] In another implementation, the key numbers used are the gun number, the line number, or the common center point number. The results obtained by each implementation are similar to those of the above embodiments, and all can intuitively identify the primary wave and ghost wave in the water and land inspection data.

[0067] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for identifying ghost waves in land and water dual-detection data, characterized in that, This includes the following steps performed sequentially: S1. Extract the odd-even sequence The odd-numbered sequence data of water inspection single guns are extracted sequentially according to the keyword number to obtain the odd-numbered sequence data of water inspection single guns. The land inspection single-gun data are extracted sequentially according to the keyword number to obtain the land inspection single-gun even sequence data; S2. Phase Twist The odd-number sequence data of single-shot water-based detectors are rotated by 90° to obtain 90° odd-number data of single-shot water-based detectors. Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne primary wave data by sequentially arranging them according to the keyword number; The odd-numbered data of a single shot from a 90° water-based detector are rotated by 180° to obtain the odd-numbered data of a single shot from a 180° water-based detector. Arrange the odd-numbered data of single-shot waterborne and even-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne ghost wave data by sequentially arranging them according to the keyword number. S3. Identify ghost waves The continuity and consistency of the in-phase axis of the interleaved display of primary wave data from land and water detection and the interleaved display of ghost wave data from land and water detection were identified respectively; among them, In the interleaved display of primary wave data from land and water inspections, those with poor continuity and consistency of the same phase axis are ghost waves, while those with good continuity and consistency of the same phase axis are primary waves. In the interleaved display of land and water ghost wave data, those with good continuity and consistency of the same phase axis are ghost waves, while those with poor continuity and consistency of the same phase axis are primary waves. The key number is the gun number, track number, line number, or common center point number.

2. A method for identifying ghost waves in land and water dual-detection data, characterized in that, This includes the following steps performed sequentially: S01. Extracting the odd-even sequence The even-numbered keyword data of the single water gun is extracted sequentially according to the keyword number to obtain the even-numbered sequence data of the single water gun. The odd-numbered sequence data of land-based single-gun inspections are extracted sequentially according to the keyword number to obtain the odd-numbered sequence data of land-based single-gun inspections. S02. Phase Twist The even-number sequence data of single-shot water-based detectors are rotated by 90° to obtain 90° even-number data of single-shot water-based detectors. Arrange the even-numbered data of single-shot waterborne and odd-numbered sequence data of single-shot landborne waterborne waterborne and landborne waterborne primary wave data by sequentially arranging them according to the keyword number; The 90° water-based single-shot even data is rotated by 180° phase to obtain the 180° water-based single-shot even data. Arrange the even-numbered data of single-shot waterborne and odd-numbered sequence data of single-shot landborne waterborne and landborne waterborne ghost wave data by sequentially arranging them according to the keyword number. S03. Identify ghost waves The continuity and consistency of the in-phase axis of the interleaved display of primary wave data from land and water detection and the interleaved display of ghost wave data from land and water detection were identified respectively; among them, In the interleaved display of primary wave data from land and water inspections, those with poor continuity and consistency of the same phase axis are ghost waves, while those with good continuity and consistency of the same phase axis are primary waves. In the interleaved display of land and water ghost wave data, those with good continuity and consistency of the same phase axis are ghost waves, while those with poor continuity and consistency of the same phase axis are primary waves. The key number is the gun number, track number, line number, or common center point number.

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