选取锡林浩特地震台2020年测震系统连续观测数据，计算背景噪声加速度功率谱密度、功率谱概率密度及1—20 Hz频段RMS值，分析该台背景噪声变化特征。研究结果表明，锡林浩特地震台三分向RMS值逐月变化规律基本一致，具体体现在：在0.01—0.1 Hz频段，水平向背景噪声值明显高于垂直向数值，差值最高可达20 dB；在0.1—1 Hz频段，三分向背景噪声值在频点0.25 Hz附近均有峰值出现，且峰值幅度呈一定季节性变化；在1—1.6 Hz频段，1—2月受新冠疫情防控影响，人类活动大幅度减少，3—12月背景噪声值有峰值出现，应为距该台约2 km的锡林浩特市人类活动所致。
This paper uses the continuous observation data of Xilinhot Seismic Station in 2020 and calculates the acceleration power spectral densities, probabilistic power spectral densities, and RMS values in the 1-20 Hz frequency band of the observation data to study the characteristics of the background noise variation of the Xilinhot Seismic Station. The results show that the three-component RMS values of the Xilinhot Seismic Station are basically the same from month to month. In the 0.01-0.1 Hz frequency band, the horizontal background noise values are significantly higher than the vertical component with the biggest difference of 20 dB. The background noise in the 0.1-1 Hz frequency band has a peak near 0.25 Hz; the peak amplitude has a certain seasonal variation. From March to December, the background noise value has a peak in the 1-1.6 Hz frequency band. This is mainly due to the influence of urban activities in Xilinhot City about 2 km away from the seismic station.
2022,43（5）: 94-99 收稿日期：2021-08-24
DOI：10.3969/j.issn.1003-3246.2022.05.012
基金项目：内蒙古自治区地震局局长基金（项目编号：2020JC14）；内蒙古自治区地震局局长基金（项目编号：2022JC05）
作者简介：段昊(1993-),男,助理工程师,主要从事地震监测工作。E-mail:603505687@qq.com
参考文献：
安全,赵艳红,苏日亚,等.内蒙古区域背景噪声特征分析[J]. 华北地震科学,2021,39(1):89-96.
蔡辉腾,陈颙,金星,等. 福建地区环境噪声特性研究[J]. 地震研究,2019,42(1):64-71.
侯颉,余大新,叶庆东,等. 北京测震台网台基背景噪声特征[J].华北地震科学,2019a,37(3):56-61.
侯颉,余大新,叶庆东,等. 北京市测震台网数字地震台站台基背景噪声分析[J]. 地震地磁观测与研究,2019b,40(4):102-107.
王俊,徐戈,孙业君.江苏省区域地表背景噪声特性的分析[J].地震研究,2009,32(2):155-161.
颜文华,张元生,秦满忠,等. 甘东南地区宽频带地震台阵背景噪声特征分析[J]. 地震学报,2016,38(5):719-727.
McNamara D E, Buland R P. Ambient noise levels in the continental United States[J]. Bull Seismol Soc Am, 2004, 94(4):1 517-1 527.
Peterson J R. Observations and modeling of seismic background noise[J]. Albuquerque:U. S. Geological Survey, 1993:93-322.
