利用接收函数计算地壳各向异性的可靠性分析及倾斜界面的影响*

地震 ›› 2016, Vol. 36 ›› Issue (2): 14-25.

利用接收函数计算地壳各向异性的可靠性分析及倾斜界面的影响^*

王琼^1,2, 高原², 钮凤林^3,4, 陈运泰¹

1.中国地震局地球物理研究所,北京 100081;
2.中国地震局地震预测研究所(地震预测重点实验室),北京 100036;
3.美国莱斯大学,休斯顿,美国;
4.中国石油大学(北京),北京 102249

收稿日期:2015-05-06 修回日期:2016-01-15 出版日期:2016-04-30 发布日期:2020-07-06
作者简介:王琼(1986-),女,山东枣庄人,博士研究生毕业,目前主要从事地震各向异性研究。
基金资助:
国家自然科学基金(41474032)与地震行业科研专项(201308011)资助

Reliability Analysis of Crustal Anisotropy from Receiver Functions and Effect of Dipping Interface

WANG Qiong^1,2, GAO Yuan², NIU Feng-lin^3,4, CHEN Yun-tai¹

1. Institute of Geophysics,CEA,Beijing 100081,China;
2. Institute of Earthquake Science,CEA,Beijing 100036,China;
3. Rice University,Houston,USA;
4. China University of Petroleum at Beijing,Beijing 102249,China

Received:2015-05-06 Revised:2016-01-15 Online:2016-04-30 Published:2020-07-06

摘要/Abstract

摘要： 使用接收函数研究壳幔速度间断面和速度结构已是常用的技术,但介质各向异性或倾斜的莫霍(Moho)界面,都会造成接收函数波形的复杂性。本文利用远震P波接收函数计算台站下方的地壳各向异性,通过信噪比测试和谐波分析两种方法来验证各向异性结果的可靠性。通过甘肃地震台网的两个台站记录,讨论各向异性和倾斜界面对接收函数的影响,结果显示,台站BYT(白银)下方具有各向异性,而台站WYT(渭源)下方由于可能存在倾斜界面,得到的各向异性结果则有待进一步分析。为了更好地认识倾斜界面对各向异性计算结果的影响,采用合成理论地震图,计算接收函数,然后利用合成接收函数进行各向异性分析。结果表明,计算得到的快波方向不会受到倾斜界面的影响,但是时间延迟会受到影响。

关键词: 各向异性, 接收函数, 倾斜界面, 谐波分析

Abstract: It is a very common technique to use receiver function to study velocity discontinuity surface between crust and upper-mantle and velocity structure.However,both anisotropy and dipping Moho can generate complicated waveforms of receiver function.We use P receiver function to determine crustal anisotropy,and then applying the signal-tonoise test and harmonic analysis to verify the reliability of the results.Using two stationsfrom Gansu province,we discuss the influence of anisotropy and dipping interface to the receiver function.It shows that the crust beneath BYT is anisotropic,while because of dipping Moho,the crustal anisotropy beneath WYT remains to be determined.In order to better understand the effect of dipping Moho to anisotropy,we use program to generate synthetic seismogram and compute the receiver function,and then make anisotropy analysis from receiver function obtained.Results show that dipping Moho will not influence the fast direction of anisotropy,but the delay time between fast and slow waves.

Key words: Crust anistropy, Receiver function, Dipping interface, Harmonic analysis

中图分类号:

P315.7

王琼, 高原, 钮凤林, 陈运泰. 利用接收函数计算地壳各向异性的可靠性分析及倾斜界面的影响^*[J]. 地震, 2016, 36(2): 14-25.

WANG Qiong, GAO Yuan, NIU Feng-lin, CHEN Yun-tai. Reliability Analysis of Crustal Anisotropy from Receiver Functions and Effect of Dipping Interface[J]. EARTHQUAKE, 2016, 36(2): 14-25.

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