| 鄂西地区宽频地震台阵背景噪声特征 |
| |
| 引用本文： | 任凤茹,谢锦赟,杨小舟.鄂西地区宽频地震台阵背景噪声特征[J].华北地震科学,2020,38(1):21-28,37. |
| |
| 作者姓名： | 任凤茹 谢锦赟 杨小舟 |
| |
| 作者单位： | 地球内部多尺度成像湖北重点实验室,中国地质大学(武汉)地球物理与空间信息学院,武汉 430074,地球内部多尺度成像湖北重点实验室,中国地质大学(武汉)地球物理与空间信息学院,武汉 430074,地球内部多尺度成像湖北重点实验室,中国地质大学(武汉)地球物理与空间信息学院,武汉 430074 |
| |
| 摘 要： | 利用鄂西地区长时间段宽频地震台站的三分量背景噪声记录,采用波形互相关方法得到台站对间的互相关函数,并通过聚束分析获得瑞雷波和勒夫波的慢度谱,研究鄂西地区背景噪声源的时空分布特征。结果表明,5~10 s周期范围,背景噪声来源于南太平洋且没有季节变化;10~20 s周期范围,慢度谱上显示明显的能量环,表明噪声源来源于多个方向,且表现出强烈和急剧的季节变化;20~40 s周期范围,慢度谱上也存在明显的能量环,其产生机制可能与此周期下提出的次重力波机制相似。在不同的周期范围内,噪声源分布方位有所不同,但在周期10~40 s范围噪声源在各方向均有分布。因此,利用长时间段连续噪声数据计算的互相关函数在周期10~40 s范围内满足背景噪声面波层析成像的理论前提。
|
| 关 键 词： | 背景噪声源 聚束分析 鄂西地区宽频地震台站 互相关函数 |
Characteristics of Ambient Seismic Noise from Broadband Seismic Array in Western Hubei Region |
| |
| REN Fengru,XIE Jinyun,YANG Xiaozhou.Characteristics of Ambient Seismic Noise from Broadband Seismic Array in Western Hubei Region[J].North China Earthquake Sciences,2020,38(1):21-28,37. |
| |
| Authors: | REN Fengru XIE Jinyun YANG Xiaozhou |
| |
| Institution: | (Hubei Key Laboratory for Multiscale Imaging of the Earth5s Interior,Institute of Geophysics and Geomatics,China University of Geosciences(Wuhan),Wuhan 430074,China) |
| |
| Abstract: | Based on the three-component ambient noise data recorded by broadband seismic stations during different time in Western Hubei, the noise cross-correlation functions between stations are calculated and stacked. The slowness spectra of Rayleigh wave and Love wave are obtained by beamforming analysis method to study the temporal and spatial distribution of ambient noise sources in Western Hubei. The results show that in the 5~10 s period of the second microseismic zone, the ambient noise originates from the South Pacific Ocean and has no seasonal variation. In the10~20 s period of the first microseismic zone, the slowness spectra shows obvious energy loop distribution, indicating that the sources of ambient noise distribute in many directions. In the longer period range of 20~40 s, there are also obvious energy loops in the slowness spectra, and the generation mechanism is likely to be similar to the mechanism of infragravity waves proposed for longer periods. In different periods, the ambient noise sources have different distributions, but there are obvious energy loops in the period of 10~40 s, which indicates that there are noise sources distributed in all directions. Therefore, the calculation of cross-correlations in the period of 10~40 s by using continuous ambient noise records in different time satisfies the theoretical premise of ambient noise surface wave tomography. |
| |
| Keywords: | ambient seismic noise source beamforming broadband seismic station in western Hubei region crosscorrelation functions |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ |
|
