张凌云^1,2,,
徐建桥^1,,,
孙和平^1,2
1. 中国科学院测量与地球物理研究所大地测量与地球动力学国家重点实验室, 武汉 430077
2. 中国科学院大学, 北京 100049

基金项目: 国家重点基础研究发展计划（973计划）（2014CB845902）和国家自然科学基金（41474062）联合资助


详细信息

作者简介: 张凌云, 男, 1987年出生, 讲师, 现主要从事地球自由振荡、面波和超导重力数据分析和研究.E-mail:zly198712280572@sina.com

通讯作者: 徐建桥, 男, 研究员、博士生导师, 主要从事有关重力场潮汐和非潮汐变化及其地球动力学意义方面的研究.E-mail:xujq@asch.whigg.ac.cn

中图分类号: P315

收稿日期:2018-10-17
修回日期:2019-08-19
上线日期:2020-04-01

The effects of crustal corrections on normal modes' frequencies

ZHANG LingYun^1,2,,
XU JianQiao^1,,,
SUN HePing^1,2
1. State Key Laboratory of Geodesy and Earth's Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China
2. University of Chinese Academy of Sciences, Beijing 100049, China


More Information

Corresponding author: XU JianQiao,E-mail:xujq@asch.whigg.ac.cn

MSC: P315

--> Received Date: 17 October 2018
Revised Date: 19 August 2019
Available Online: 01 April 2020


摘要
摘要:该文通过对CRUST2.0+PREM 16200个区域一维地球模型简正模频率的计算，得到简正模非线性地壳改正效应.结果表明：地壳改正的非线性化改正不可或缺，对于低频简正模，其影响较小；对于高频简正模，其影响较大，这一变化遵循能量密度函数分布规律.此外，该文将CRUST2.0网格数据展开成球谐函数，并在此基础上计算了地壳侧向非均匀导致的二阶谱峰分裂系数.将其与地幔对应系数比较得出：前者造成的简正模谱峰分裂通常远远小于后者；地壳造成的二阶谱峰分裂主要贡献来自于间断面地形起伏（地壳厚度等）而非地壳的侧向非均匀参数扰动；在反演地幔结构时必须扣除地壳对简正模谱峰分裂系数的影响.
关键词: 地壳改正/
简正模/
谱峰分裂系数/
侧向非均匀

Abstract:In this paper, the global 3D crust model CRUST2.0 was imposed on PREM so that 16200 local 1D Earth models were generated. The nonlinear crustal corrections were built through computing their corresponding frequencies. The results implied that the crustal correction were necessary. The center frequency misfit due to nonlinear crustal correction is relatively small for the low frequency normal modes while it becomes large with the overtone and angular degree improving which obeys the energy distribution discipline. Then the second order splitting coefficients of mantle had been computed and compared with mantle. The results demonstrate that the crustal splitting coefficients are often far less than mantle's. The dominant contribution is from the discontinuity of crust rather than the lateral heterogeneity. It's necessary to proceed the crustal corrections when inversing the structure of mantle.
Key words:Crustal correction/
Normal modes/
Splitting coefficients/
Lateral heterogeneity



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