Application of normal Morlet wavelet transform method to the damped harmonic analysis: On the isolation of the seismic normal modes (S-0(0) and S-0(5)) in time domain
文献类型:期刊论文
作者 | Duan, Pengshuo2; Huang, Chengli1,2 |
刊名 | PHYSICS OF THE EARTH AND PLANETARY INTERIORS
![]() |
出版日期 | 2019-03-01 |
卷号 | 288页码:26-36 |
关键词 | Seismic normal mode NMWT method Beating-frequency behaviors Earth's free oscillation Wavelet analysis |
ISSN号 | 0031-9201 |
DOI | 10.1016/j.pepi.2019.01.005 |
英文摘要 | Previous studies indicated that the seismic breathing normal modes S-0(0) (period similar to 20.5 min) and S-0(5) (period similar to 19.8 min) were excited by the 26th December 2004 Sumatra-Andaman earthquake. These two modes may present a beating-pattern in a wavelet time-frequency spectrum due to their close frequencies. Using superconducting gravimeter (SG) data covering 20 days after the Sumatra event, this work shows that a periodic amplitude-varying signal with an similar to 20.2 min period due to beating between the S-0(0) and S-0(5) modes is displayed in the normal Morlet wavelet transform (NMWT) spectrum, and this signal can be quantitatively extracted from the NMWT spectrum. Furthermore, the NMWT spectrum also clearly shows that this beating-pattern disappeared at time t similar to 9 x 10(3) min (when the S-0(5) mode vanished) after the Sumatra event occurred, since S-0(5) mode decays much faster than the S-0(5) mode. Using this information, we can separately isolate the S-0(0) and S-0(5) mode signals and further estimate their respective parameters (i.e., frequency-f(0), initial amplitude-A(0), and quality factor-Q) in the time domain rather than in the frequency domain only. The temporal-varying behaviour of the oSs mode in the time domain obtained in this work can be thoroughly explained by two damped harmonic signals due to the splitting of the S-0(5) mode. In brief, we can isolate S-0(0) and S-0(5) mode signals in the time-frequency domain using the NMWT method, which is different from the traditional method used in the frequency domain. |
资助项目 | National Natural Science Foundation of China[11803064] ; National Natural Science Foundation of China[41774017] ; National Natural Science Foundation of China[11773058] ; China Postdoctoral Science Foundation[2017M621561] |
WOS研究方向 | Geochemistry & Geophysics |
语种 | 英语 |
WOS记录号 | WOS:000463307400003 |
出版者 | ELSEVIER SCIENCE BV |
源URL | [http://119.78.226.72/handle/331011/31841] ![]() |
专题 | 中国科学院上海天文台 |
通讯作者 | Duan, Pengshuo; Huang, Chengli |
作者单位 | 1.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Shanghai Astron Observ, CAS Key Lab Planetary Sci, Shanghai 200030, Peoples R China |
推荐引用方式 GB/T 7714 | Duan, Pengshuo,Huang, Chengli. Application of normal Morlet wavelet transform method to the damped harmonic analysis: On the isolation of the seismic normal modes (S-0(0) and S-0(5)) in time domain[J]. PHYSICS OF THE EARTH AND PLANETARY INTERIORS,2019,288:26-36. |
APA | Duan, Pengshuo,&Huang, Chengli.(2019).Application of normal Morlet wavelet transform method to the damped harmonic analysis: On the isolation of the seismic normal modes (S-0(0) and S-0(5)) in time domain.PHYSICS OF THE EARTH AND PLANETARY INTERIORS,288,26-36. |
MLA | Duan, Pengshuo,et al."Application of normal Morlet wavelet transform method to the damped harmonic analysis: On the isolation of the seismic normal modes (S-0(0) and S-0(5)) in time domain".PHYSICS OF THE EARTH AND PLANETARY INTERIORS 288(2019):26-36. |
入库方式: OAI收割
来源:上海天文台
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。