海底与陆地台站背景噪声差异  

Seismic ambient noise difference between OBS and land stations

作　　者：王嗣尹 徐彦[1] 李晓梦 解朝娣[1] WANG Siyin;XU Yan;LI Xiaomeng;XIE Zhaodi(Department of Geophysics,School of Earth Sciences,Yunnan University,Kunming 650500,China)

机构地区：[1]云南大学地球科学学院地球物理系,中国昆明650500

出　　处：《地震地磁观测与研究》2021年第6期127-136,共10页Seismological and Geomagnetic Observation and Research

基　　金：云南大学研究生科研创新基金(批准号:2020190);国家自然科学基金(批准号:41564003,41964001)。

摘　　要：地震台站按位置可分为陆地台和海底台(Ocean Bottom Seismograph,OBS),为了研究OBS与陆地台站记录的频谱特征差异,采用偏振分析法获得2类记录周期为0.1—100 s的地震背景噪声频谱极化特征。OBS台站与陆地台站的频谱分析结果表现出较大差异。陆地台站均能记录到第一地脉动信号,而OBS台站则不能。陆地台的第二地脉动信号均表现出瑞利波质点运动特征,而OBS台仅个别台站信号显示线性运动特征。台站环境是这一观测结果的主要影响因素,OBS相较于陆地台会受到更多来自海底湍流的影响,而湍流削弱了地脉动信号的信息。Seismic stations can be divided into land stations and Ocean Bottom Seismograph(OBS)stations by location.In order to study the difference in spectral characteristics between OBS and land stations,we use polarization analysis to obtain the spectral polarization characteristics of seismic ambient noise recorded by OBS and land stations with a period of 0.1-100 s.The spectral analysis results of OBS stations and land stations show a great difference.All land stations can record the Single-Frequency microseism signal,but OBS stations cannot.The Double-Frequency microseism signals recorded by land stations all show the characteristics of Rayleigh wave particle motion,and only a few OBS stations show linear motion characteristics.The main influencing factors are the station environment.Compared with land stations,OBS stations are affected more by ocean floor turbulence,which weakens the information of the microseism signal.

关 键 词：偏振分析 背景噪声 极化属性 瑞利波 OBS 

分 类 号：P315.7[天文地球—地震学]