• 固体地球物理及空间物理学（大气、行星、地球动力学、重磁电及地震学、地热学） •

谱白化叠加方法在气枪信号检测中的应用

1. 1. 中国地震局工程力学研究所和中国地震局地震工程与工程振动重点实验室,哈尔滨 150000
2. 福建省地震局,福州 350000
• 收稿日期:2017-10-18 修回日期:2018-07-22 出版日期:2018-08-20 发布日期:2018-09-13
• 作者简介:金震,男,1985年生,云南大理人,工程力学研究所在读博士,现为厦门地震勘测研究中心工程师,主要从事地球深部构造方面的研究. (E-mail: 358450071@qq.com)
• 基金资助:
国家自然科学基金项目(41474071);地震行业科研专项项目(2015419015);中国地震局工程力学研究所基本科研业务费专项资助项目(2016A03)

Application of whitening stack method in picking up the air gun signal

JIN Zhen1,2,LI Shan-you1,CAI Hui-teng2,LI Pei2,LI Hai-yan2,XU Jia-jun2

1. 1. Institute of Engineering Mechanics, China Earthquake Administration, Key Laboratory of Earthquake Engineering and Engineering Vibration, China Earthquake Administration, Harbin 150000, China
2. Earthquake Administration of Fujian Province, Fuzhou 350000, China
• Received:2017-10-18 Revised:2018-07-22 Online:2018-08-20 Published:2018-09-13

Abstract:

The active source gun signal has many advantages, such as environmental protection, low frequency signal, high propagation distance and high repeatability. It is widely used in deep detection and monitoring media changes of regional scale. How to identify signals accurately and efficiently is the key point of air gun signal processing. The ability to detect signals depends on the signal to noise ratio of observed records. In order to improve the signal-to-noise ratio of seismic records, filtering, denoising and superposition are often used. In order to improve the Signal to Noise Ratio (SNR) of gun signals with high repetition, the method of superposition is adopted to improve the signal to noise ratio. Here, we based on the characteristics of air gun signal, derived equivalence relation between linear superposition and spectrum whitening. From the point of view of numerical simulation and actual air gun recording, we analyze and study the signal pickup ability of linear superposition, spectral whitening superposition and weighted superposition. The result shows that:compared to the linear superposition and weighted superposition, spectrum whitening and template signal superimposed with high degree of similarity, the weak signal pickup ability. However, these capabilities have certain scope of application. On the other hand, the correctness and rationality of the numerical simulation analysis are verified by the analysis of the actual record. Therefore, the linear superposition of the near field of gun signal should be adopted, and the far field should be spectrum whitening. The signal in seismic section continuous tracking can be used weighted superposition of results, this is because the weighted sum of SNR is most obvious; seismic phase suggested by linear superposition or spectral whitening results, this is because of the above two methods will not produce phase shift and phase distortion.