对云龙湖实验室山洞台站的勘选数据进行分析,并对地铁干扰、施工活动、观测仪器的性能进行评估。结果表明,实验室施工干扰是地震台站观测的主要干扰源,尤其在07:00—18:00之间,施工引起的地动噪声频率主要集中在3—15 Hz;地铁主要干扰频率为3—15 Hz,且5—10 Hz干扰较明显。根据数字地震测震台勘选要求,对台址进行评估时需计算台基背景噪声在1—20 Hz频带范围内的地动速度噪声RMS值,计算结果表明,云龙湖实验室台基条件良好,山洞内台基噪声为Ⅰ类噪声水平。
This paper analyzed the site selection data for the Yunlong Lake Laboratory Cave Seismic Station, and evaluated subway interference, construction activities, and the performance of the observation instruments. The results indicate that construction interference is the main source of disturbance for the seismic station’s observation, especially between 07:00 and 18:00 in one day, with construction-induced seismic noise primarily concentrated in the frequency range of 3-15 Hz. The main frequency of subway interference ranges from 3 to 15 Hz, and disturbance from frequency ranging from 5 to 10 Hz is more significant. According to the requirements for digital seismicsite selection, the evaluation of the site should calculate the RMS value of seismic station background noise in the 1-20 Hz frequency band. The calculation results show that the site conditions at Yunlong Lake Laboratory are good, with cave-based noise classified as Level I.
2024,45(4): 83-90 收稿日期:2024-5-13
DOI:10.3969/j.issn.1003-3246.2024.04.011
基金项目:连云港市科技局重点研发计划(社会发展)(项目编号:SF2326);中国地震局地震科技星火计划攻关项目(项目编号:XH24018C);江苏省地震局青年科研基金(项目编号:202412);江苏省地震局青年科研基金(项目编号:202413)
作者简介:立凯(1985—),男,本科,工程师,主要从事地震监测等工作。E-mail:83411367@qq.com
*通讯作者:高明智(1987—),男,本科,工程师,主要从事地震监测等工作。E-mail:61689120@qq.com
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