选取2015年四川数字测震台网中筠连和华蓥山地震台记录的垂直分向连续波形数据，利用Matlab软件，计算地震台站台基噪声功率谱概率密度函数，分析地震台站环境噪声特征。结果表明，台站环境噪声功率谱密度概率密度分布对地震事件波形（体波、面波）、人为噪声（台站周围人为活动、车辆及机器噪声等高频干扰）、系统瞬变（数据丢失、地震计小故障）以及仪器标定信号等反映较好。使用台基噪声功率谱概率密度函数方法，有利于监测地震台站数据记录，提高观测数据质量。
This paper introduces the design of the program for calculating the probability density function (PDF) of power spectral density (PSD) curves form seismic noise based on the Matlab software. And we computed the PDF of station JLI and HYS BHZ in Sichuan Digital Seismic Network, using PSDs during the period from January to December, 2015. The results manifest the region of the PDF is dominated by high power occurrences of naturally occurring earthquakes (body and surface waves), cultural nosie (source from actions of human being, traffic and machinery energy into the Earth), and recording system transients (data gaps and sensor glitches). And the calibrations are easily identifiable in the PDF. The PSD-PDF method can be helpful to monitor data of seismic stations and improve the quality of seismic data.
2018,39(2): 84-89 收稿日期：2017-03-09
DOI：10.3969/j.issn.1003-3246.2018.02.012
基金项目：国家科技支撑计划（项目编号：2014BAK03B04）；四川省地震局科技专项（项目编号：LY1618，LY1810，LY1505）
作者简介：谢江涛(1986-),男,硕士研究生,工程师,主要从事数字地震观测、地震预警及背景噪声层析成像研究工作。E-mail:jiangtaoxie@outlook.com
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