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《地震研究》[ISSN:1000-0666/CN:53-1062/P]

卷:

40

期数:

2017年04期

页码:

595-604

栏目:

主动源专栏

出版日期:

2017-09-20

文章信息/Info

Title:

A Study on “Pair Difference” Method to Improve Precision of Signal Travel Time Drift under Low Signal-Noise ratio

作者:

黄亦磊; 运乃丹; 周仕勇

(北京大学 理论与应用地球物理研究所,北京 100871)

Author(s):

HUANG Yilei; YUN Naidan; ZHOU Shiyong

(Institute of Theoretical and Applied Geophysics,Peking University,Beijing 100871,China)

关键词:

主动源;  走时变化;  走时台差法;  信噪比

Keywords:

active source;  travel time drift;  pair difference method;  signal-noise ratio

分类号:

P315.31

DOI:

-

摘要:

为研究噪音对主动源信号走时变化提取精度的影响,采用对比数值实验的方法。按照常规流程,首先用反褶积去除震源激发时间的不确定性干扰,压缩子波以得到更加尖锐的震相,由于发现反褶积会降低信号的信噪比,于是提出了台差法来代替反褶积矫正气枪激发的不确定性,再结合干涉法提取走时变化,并定量对比了两者的走时变化提取精度,最后尝试用台差法提取主动源走时的日变化。结果表明,台差法可以有效矫正震源激发时刻的影响,且不降低信噪比,从而也能获得较高走时变化提取的精度。

Abstract:

We adapt numerical tests to study the influence of noises on the precision of travel time drift of active source signals.In traditional ways,deconvolution is used to eliminate the uncertainty of the excitation time of active source.However,this process will significantly lower the signal-noise ratio and thus lead the decline of precision.We put forward a new method named pair difference to replace deconvolution for the sake of eliminating the influence of the active source.The results show that pair difference can effectively eliminate the impact of active source and will not affect the signal-noise ratio,thus improving the precision of extracting travel time drifts.

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备注/Memo

备注/Memo:

收稿日期:2017-04-11
基金项目:云南省陈颙院士工作站(2014IC007)、中国地震研究专项(201508009)和中国国家自然科学基金(41474033)联合资助.

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更新日期/Last Update: 2017-09-20