基于时变窄带滤波技术提取可控震源扫频信号方法研究

发布时间：2018-04-13 02:03

本文选题：精密控制震源 + 谐振器　；参考：《地震》2015年03期

【摘要】：精密主动地震监测为我们主动探测地下介质结构,并监视其动态变化提供了一条可能的技术途径。由于精密控制震源释放的能量强度小,随着传播距离的增加,信号的快速衰减,在离震源较远处有用的震源信号被掩盖在很强的噪声中,这对于震相的识别与走时的拾取精度有着很大的影响。本文设计了一种时变窄带滤波器进行更为精细的滤波,期望进一步提高观测数据信噪比,再结合匹配滤波方法实现主动震源信号的检测与波形变换。另外,由于不同震相有一定的到时差,使用时变窄带滤波器提取一个震相波形信息时,将压制其他震相的波形信号,从而实现了震相分离的技术。仿真计算与实际资料处理显示了该方法在提高观测资料质量、震相识别分辨率及震相分离方面具有一定的有效性与优越性。通过对广东省新丰江库区精密可控震源试验数据进行时变窄带滤波方法的处理,在震中距为200km左右处的台站记录中检测到主动源信号,体现了对远台弱信号的提取能力。
[Abstract]:Precision active seismic monitoring provides a possible technical approach for us to actively detect the structure of underground media and monitor its dynamic changes.Due to the small energy intensity released by the precise control source, with the increase of the propagation distance and the rapid attenuation of the signal, the useful source signal in the distance from the source is masked in a very strong noise.This has a great influence on the identification of seismic phase and the picking accuracy of walking time.In this paper, a time-varying narrow-band filter is designed to improve the signal-to-noise ratio (SNR) of the observed data, and then the active source signal detection and waveform transformation are realized by using the matched filtering method.In addition, because different seismic phases have certain time difference, when using time-varying narrow band filter to extract the waveform information of one phase, the waveform signals of other phases will be suppressed, thus the technique of phase separation is realized.Simulation and actual data processing show that this method is effective and superior in improving the quality of observation data, phase identification resolution and phase separation.By processing the precision vibroseis test data in Xinfengjiang Reservoir area of Guangdong Province, time-varying narrow band filtering method is used to detect the active source signals in the records of stations with the epicentral distance of 200km, which reflects the ability to extract weak signals from the far station.
【作者单位】：中国地震局地震预测重点实验室中国地震局地震预测研究所;
【基金】：中国地震局地震预测研究所基本科研业务费专项(2014IES0202)资助
【分类号】：P631.4

【共引文献】