Marine air gun source synchronous excitation method
By dynamically adjusting the airgun calibration delay in the marine airgun source system, synchronous excitation with microsecond-level timing accuracy was achieved, solving the adaptability and accuracy problems of airgun synchronous control in marine environments, and improving the data quality and system stability of marine seismic exploration.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BGP INC CHINA NAT PETROLEUM CORP
- Filing Date
- 2025-12-22
- Publication Date
- 2026-05-19
AI Technical Summary
Existing marine air gun synchronization control technology has poor adaptability and insufficient coordination accuracy in complex marine environments, making it difficult to meet the excitation consistency requirements of high-precision seismic exploration and affecting the quality of data acquisition and the reliability of interpretation.
The air gun's firing time is determined by the navigation system. The signal peak value is calculated and the actual time delay is calibrated using the gun delay algorithm processing module. The air gun calibration delay is dynamically adjusted to achieve synchronous firing with microsecond-level timing accuracy. The calibration value is updated in real time and the firing time is corrected.
It significantly improves the synchronization speed and stability of the air gun array, enhances data acquisition quality and reliability, reduces equipment failure rate and maintenance costs, and improves excitation efficiency.
Smart Images
Figure CN122063676A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of marine exploration technology, and in particular to a method for synchronous excitation of a marine air gun seismic source. Background Technology
[0002] In marine seismic exploration, the synchronization accuracy of the air gun array, as a crucial artificial seismic source system, is one of the core factors determining the quality of seismic data acquisition and the reliability of subsequent geological structural interpretation. Traditional air gun synchronization control methods mostly employ fixed-delay strategies. While these methods can achieve a certain degree of synchronized excitation under ideal conditions, in the complex marine environment, they suffer from poor adaptability, limited multi-device coordination accuracy, and insufficient synchronization response speed due to the coupled influence of multiple factors such as waves, currents, temperature changes, and communication delays between devices. These issues make it difficult to meet the stringent requirements of high-precision seismic exploration for excitation consistency.
[0003] In recent years, to overcome the aforementioned limitations, some studies have begun to explore delay optimization control techniques based on adaptive strategies, attempting to improve synchronization performance by dynamically adjusting the excitation timing. However, such methods still generally face challenges in practical applications, such as complex algorithm structures and high computational resource consumption. Especially in the dynamic and frequently disturbed marine working environment, the stability and reliability of their synchronization control still need to be improved. These technical bottlenecks not only limit further improvements in the excitation synchronization accuracy and response speed of airgun arrays, but also constrain the overall quality, consistency, and interpretability of marine seismic exploration data.
[0004] Therefore, in view of the problems of poor adaptability, insufficient coordination accuracy and poor system stability of existing air gun synchronous control technology, there is an urgent need to propose a new method for synchronous excitation of marine air gun sources, which can achieve higher precision excitation timing control in complex marine environments, thereby effectively ensuring the quality, reliability and consistency of marine seismic exploration data acquisition. Summary of the Invention
[0005] This invention addresses the problems in existing marine airgun control technology caused by environmental fluctuations, equipment response differences, and signal propagation delays, proposing a method for synchronous excitation of a marine airgun source, specifically including: S1: Determine the air gun firing time, which is sent from the navigation system to the main control system of the gun controller; S2: Set the air gun acquisition time and firing preparation time, and transmit the acquisition time and firing preparation time to the gun delay algorithm processing module in the main control system of the gun controller. The gun delay algorithm processing module performs data processing according to the preset algorithm to determine the final air gun calibration delay. S3: Calculate the difference between the gun preparation time and the air gun acquisition time, compare the difference with the final air gun calibration delay, and send the updated reasonable calibration value to the corresponding air gun in real time.
[0006] Specifically, in step S2, the air gun sampling time is shorter than the firing preparation time.
[0007] Specifically, the gun delay algorithm processing module includes determining the signal peak value, calculating the actual delay of the air gun, and calculating the air gun calibration delay.
[0008] Specifically, the preset algorithm in step S2 includes: S21: Calculate the actual firing moment of the air gun by comparing the signal peak value and the threshold value; S22: Calculate the actual time delay of the air gun based on the gun preparation time and the actual firing time of the air gun; S23: Calculate the air gun calibration delay according to the set algorithm.
[0009] Specifically, step S21 includes: To determine the signal peak value, the signal collected by the gun action sensor is divided into segments by a sliding window to calculate the sum of the signals within each window. The window corresponding to the maximum value is found, and the median value of that window is the signal peak value.
[0010] Specifically, step S21 further includes: when the signal peak value is greater than the threshold, the time corresponding to the signal peak value is the actual firing time of the air gun.
[0011] Specifically, the actual time delay of the air gun satisfies the formula: T D =T P -(T0+T A ); Wherein: T D For the actual delay of the air gun, T P T0 represents the actual firing moment of the air gun, and T represents the firing moment of the air gun. A The moment to prepare to fire.
[0012] Specifically, step S23 includes: When the actual delay of the air gun is less than a1 times the sampling interval of the signal collected by the gun action sensor, T is set. TA =T D / b1, when the actual delay of the air gun is between a1 and a2 times the sampling interval of the signal acquired by the gun action sensor, set T TA =T D / b2, when the actual delay of the air gun is greater than a2 times the sampling interval of the signal collected by the gun action sensor, the air gun calibration delay T is set. TA =T D / b3; Among them, T TA For air gun calibration delay, T D For the actual time delay of the air gun, a2 is greater than a1, and b3 is greater than b2, which is greater than b1.
[0013] Specifically, step S2 also includes: The final airgun calibration delay is the sum of the airgun calibration delay and the final airgun calibration delay of the previous shot, satisfying the formula: T Next[N] =T Next[N-1] +T TA ; Among them, T Next[N] For the final air gun calibration delay, T Next[N-1] For the final air rifle calibration delay of the previous shot, T TA Delay for air gun calibration.
[0014] Specifically, step S3 also includes: When the absolute value of the final air gun calibration delay is less than the difference between the gun preparation time and the air gun acquisition time, the final air gun calibration delay is sent to the air gun. When the absolute value of the final air gun calibration delay is greater than the difference between the firing preparation time and the air gun acquisition time, it is confirmed that there is an abnormal delay in the air gun system.
[0015] Compared to existing air gun synchronization control technology, the advantages are as follows: 1. By dynamically calculating and compensating for the excitation delay of each air gun, the excitation timing correction with microsecond-level timing accuracy was achieved, thereby significantly improving the synchronization speed and operational stability of the air gun array excitation and ensuring the quality and reliability of data acquisition.
[0016] 2. It can control the synchronous excitation error of multiple air guns within the millisecond range, which greatly improves the synchronization accuracy and enables the air gun source system to achieve synchronous excitation of all air guns in a smaller number of excitations, thus greatly improving the excitation efficiency.
[0017] 3. Under long-term continuous operation conditions, the system can still maintain stable synchronous excitation performance, which significantly reduces the equipment failure rate caused by synchronization failure, reduces the maintenance frequency and operation and maintenance costs of the air gun, and thus effectively reduces the operating cost. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 Flowchart of the method for synchronous excitation of air gun source; Figure 2 Flowchart of the main control system for the gun controller. Detailed Implementation
[0020] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. Based on the description of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.
[0021] Unless otherwise explicitly specified and limited, the terms "setup," "installation," and "connection" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms based on the specific circumstances.
[0022] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.
[0023] The terms “first,” “second,” “third,” etc., are used merely to distinguish elements with similar properties, not to indicate or imply relative importance or a specific order.
[0024] The terms “include,” “comprising,” or any other variation thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.
[0025] Reference Figure 1 and Figure 2 As shown, the present invention provides a method for synchronous excitation of a marine air gun source, comprising the following steps: S1: Determine the air gun firing time, which is sent from the navigation system to the main control system of the gun controller. S2: Set the air gun acquisition time and firing preparation time, and transmit the acquisition time and firing preparation time to the gun delay algorithm processing module in the main control system of the gun controller. The gun delay algorithm processing module processes the data according to the preset algorithm to determine the final air gun calibration delay. Specifically, the firing preparation time is the time required from when the air gun receives the "fire" command from the navigation system to when the air gun actually fires. This is due to the delay in command transmission and the air gun's own mechanical delay. The acquisition time is the moment when the air gun's motion sensor begins to acquire data. The acquisition time must be earlier than the firing preparation time, i.e., shorter than the firing preparation time. This captures the entire mechanical motion process of the air gun from receiving the command to completing firing (and even afterwards) for performance monitoring, fault diagnosis, and accurate verification of the firing time.
[0026] The gun delay algorithm processing module in the main control system of the gun controller mainly includes determining the signal peak value, calculating the actual delay of the air gun, and calculating the calibration delay of the air gun.
[0027] Furthermore, the preset algorithms of the gun delay algorithm processing module include: S21: Calculate the actual firing moment of the air gun by comparing the signal peak value and the threshold value; The signal acquired by the gun motion sensor is processed by segmenting the signal into a sliding window. The sum of the signals within each window is calculated, and the window corresponding to the maximum value is found. The median value of this window is the signal peak value. For example, the signal sequence is: x=[x0,x1,…,xN] [1] There are N sample points in total. The sliding window size is W=10, and the window moves by a step size S=1 each time.
[0028] To filter out noise in the acquired signals and ensure that valid signals are identified, a threshold is set. The signal peak value is compared with the set threshold. If the signal peak value is greater than the threshold, the signal is considered valid, and the time corresponding to the signal peak value is the actual firing time of the air gun. If the signal peak value is less than the threshold, the signal is considered noise and not normally acquired data.
[0029] S22: Calculate the actual time delay of the air gun based on the gun preparation time and the actual firing time of the air gun; The actual time delay of the air gun satisfies the formula: T D =T P -(T0+T A ), where: T D For the actual delay of the air gun, T P T0 represents the actual firing moment of the air gun, and T represents the firing moment of the air gun. A The moment to prepare to fire.
[0030] S23: Calculate the air gun calibration delay according to the set algorithm.
[0031] Due to factors such as mechanical delay, propagation delay, system delay, and environmental disturbances, directly using the actual time delay of the air gun for calibration would fail to separate many delay factors. This invention uses an algorithm to calculate the air gun calibration delay based on the air gun's time delay. The specific algorithm includes: When the actual delay of the air gun is less than a1 times the sampling interval of the signal collected by the gun action sensor, T is set. TA =T D / b1, when the actual delay of the air gun is between a1 and a2 times the sampling interval of the signal acquired by the gun action sensor, set T TA =T D / b2, when the actual delay of the air gun is greater than a2 times the sampling interval of the signal collected by the gun action sensor, set T TA =T D / b3; where T TA For air gun calibration delay, T D The actual delay of the air gun is given by a2 > a1, b3 > b2 > b1. For example, a1 is 5, a2 is 10, b1 is 2, b2 is 3, and b3 is 5.
[0032] Furthermore, the air gun calibration delay calculated after this firing is added to the previously determined final air gun calibration delay. That is, the final air gun calibration delay is the sum of the current air gun calibration delay and the previous final air gun calibration delay, satisfying the formula: T Next[N] =T Next[N-1] +T TA ; Among them, T Next[N] For the final air gun calibration delay, T Next[N-1] For the final air rifle calibration delay of the previous shot, T TA Delay for air gun calibration.
[0033] S3: Calculate the difference between the gun preparation time and the air gun acquisition time, compare the difference with the final air gun calibration delay, and send the reasonable calibration value to the corresponding air gun in real time.
[0034] When the absolute value of the final air gun calibration delay is less than the difference between the gun preparation time and the air gun acquisition time, the final air gun calibration delay is sent to the air gun; when the absolute value of the final air gun calibration delay is greater than the difference between the gun preparation time and the air gun acquisition time, an abnormal delay in the air gun system is confirmed.
[0035] For example, the firing preparation time is set to 50 milliseconds, and the acquisition time of the air gun's motion sensor is set to 20 milliseconds, with a difference of 30 milliseconds. If the absolute value of the final air gun calibration delay is greater than 30 milliseconds, it indicates an abnormal delay in the air gun system, suggesting a potential system malfunction, and the calibration delay for that instance is assigned a value of 0. If the absolute value of the final air gun calibration delay is less than 30 milliseconds, it is considered a reasonable calibration delay and is sent to the air guns to ensure time synchronization of air gun firing. Furthermore, it can control the synchronous firing error of multiple air guns within the millisecond range, significantly improving synchronization accuracy and enabling the air gun source system to achieve synchronous firing of all air guns within a fewer firing cycles, greatly improving firing efficiency.
[0036] In summary, this invention solves the problem of asynchronous excitation caused by factors such as the air gun's mechanical characteristics, signal transmission, and changing environment. By analyzing the signals collected during air gun excitation, the actual time delay of the air gun is determined, and the final air gun calibration time delay is further determined based on the algorithm. This achieves excitation timing correction with microsecond-level timing accuracy, ensuring the time synchronization and operational stability of each air gun excitation, and guaranteeing the quality and reliability of data acquisition. Furthermore, under long-term continuous operation conditions, the system can still maintain stable synchronous excitation performance, significantly reducing the equipment failure rate caused by synchronization failure, reducing the frequency of air gun maintenance and operating costs, and thus effectively reducing operating costs. It is applicable to various scenarios such as marine seismic exploration, seabed resource detection, and underwater engineering monitoring.
[0037] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for synchronous excitation of a marine air gun source, characterized in that, Includes the following steps: S1: Determine the air gun firing time, which is sent from the navigation system to the main control system of the gun controller; S2: Set the air gun acquisition time and firing preparation time, and transmit the acquisition time and firing preparation time to the gun delay algorithm processing module in the main control system of the gun controller. The gun delay algorithm processing module performs data processing according to the preset algorithm to determine the final air gun calibration delay. S3: Calculate the difference between the gun preparation time and the air gun acquisition time, compare the difference with the final air gun calibration delay, and send the reasonable calibration value to the corresponding air gun in real time.
2. The method for synchronous excitation of a marine air gun source as described in claim 1, characterized in that, In step S2, the air gun sampling time is shorter than the firing preparation time.
3. The method for synchronous excitation of a marine air gun source as described in claim 1, characterized in that, The gun delay algorithm processing module includes determining the signal peak value, calculating the actual delay of the air gun, and calculating the air gun calibration delay.
4. The method for synchronous excitation of a marine air gun source as described in claim 1, characterized in that, The preset algorithm mentioned in step S2 includes: S21: Calculate the actual firing moment of the air gun by comparing the signal peak value and the threshold value; S22: Calculate the actual time delay of the air gun based on the gun preparation time and the actual firing time of the air gun; S23: Calculate the air gun calibration delay according to the set algorithm.
5. The method for synchronous excitation of a marine air gun source as described in claim 4, characterized in that, Step S21 includes: To determine the signal peak value, the signal collected by the gun action sensor is divided into segments by a sliding window to calculate the sum of the signals within each window. The window corresponding to the maximum value is found, and the median value of that window is the signal peak value.
6. The method for synchronous excitation of a marine air gun source as described in claim 4, characterized in that, Step S21 further includes: when the signal peak value is greater than the threshold value, the time corresponding to the signal peak value is the actual firing time of the air gun.
7. The method for synchronous excitation of a marine air gun source as described in claim 4, characterized in that, The actual time delay of the air gun satisfies the formula: T D =T P -(T0+T A ); Wherein: T D For the actual delay of the air gun, T P T0 represents the actual firing moment of the air gun, and T represents the firing moment of the air gun. A The moment to prepare to fire.
8. The method for synchronous excitation of a marine air gun source as described in claim 4, characterized in that, Step S23 includes: When the actual delay of the air gun is less than a1 times the sampling interval of the signal collected by the gun action sensor, T is set. TA =T D / b1, when the actual delay of the air gun is between a1 and a2 times the sampling interval of the signal acquired by the gun action sensor, set T TA =T D / b2, when the actual delay of the air gun is greater than a2 times the sampling interval of the signal collected by the gun action sensor, the air gun calibration delay T is set. TA =T D / b3; Among them, T TA For air gun calibration delay, T D For the actual time delay of the air gun, a2 is greater than a1, and b3 is greater than b2, which is greater than b1.
9. The method for synchronous excitation of a marine air gun source as described in claim 1, characterized in that, Step S2 also includes: The final airgun calibration delay is the sum of the airgun calibration delay and the final airgun calibration delay of the previous shot, satisfying the formula: T Next[N] =T Next[N-1] +T TA ; Among them, T Next[N] For the final air gun calibration delay, T Next[N-1] For the final air rifle calibration delay of the previous shot, T TA Delay for air gun calibration.
10. The method for synchronous excitation of a marine air gun source as described in claim 1, characterized in that, Step S3 also includes: When the absolute value of the final air gun calibration delay is less than the difference between the gun preparation time and the air gun acquisition time, the final air gun calibration delay is sent to the air gun. When the absolute value of the final air gun calibration delay is greater than the difference between the firing preparation time and the air gun acquisition time, it is confirmed that there is an abnormal delay in the air gun system.