选取2022年5月和7月乌加河地震台测震和重力观测数据，应用噪声功率谱概率密度（PDF）方法，对比分析疫情防控政策背景下该台背景噪声变化，探究人类活动对观测数据的影响。结果发现：①测震数据记录：与2022年5月相比，7月噪声RMS值明显减小，分析认为，该月受乌加河地区疫情防控措施影响，人类活动减弱，表明人类活动对测震观测数据具有显著影响；②重力观测数据：在2个观测时段，置于同一观测山洞的重力仪背景噪声记录几乎无差别，表明人类活动对重力观测数据的影响较小，重力仪基本不受台站背景噪声的影响，从而验证了测震数据的准确、可靠。综合分析认为，人类活动对乌加河地震台背景噪声有一定影响，但重力仪由于其特性，观测数据基本不受人类活动影响。
The seismic and gravity observation data of the Wujiahe Seismic Station in May and July 2022 were selected, and the noise power spectrum probability density (PDF) method was applied to compare and analyze the background noise change of the station under the context of epidemic prevention and control policies, and the influence of human activities on the observation data was explored. The results show that:① Recorded seismic data:Compared with May 2022, the noise RMS value in July decreased significantly. The analysis suggests that human activities are weakened due to the epidemic prevention and control measures in the Wujiahe area, indicating that human activities have a significant impact on the seismic observation data. ② Gravity observation data:During the two observation periods, there was almost no difference in the background noise records of the gravimeter placed in the same observation cave, indicating that human activities had a small influence on the gravity observation data, and the gravimeter was basically not affected by the background noise of the station, thus verifying the accuracy and reliability of the seismic data. The comprehensive analysis concludes that human activities have a certain effect on the background noise of the Wujiahe Seismic Station. However, the observation data of the gravimeter are basically not affected by human activities because of its characteristics.
2023,44（3）: 107-114 收稿日期：2022-09-30
DOI：10.3969/j.issn.1003-3246.2023.03.015
基金项目：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
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