徐庄子地震台地磁观测干扰因素剖析

An analysis of the disturbance factors of geomagnetic observation at Xuzhuangzi Seismic Station

为充分认识地磁观测环境中的各种干扰因素,提升台站观测人员对数据异常的识别能力,确保提供真实有效的高质量观测数据,以天津市徐庄子地震台地磁观测为例,阐述地磁观测中存在的多种干扰因素及形态特征和预处理方法。分析表明,徐庄子地震台地磁GM4磁通门磁力仪主要受高压直流输电、地铁运营、过往车辆、地电供电、GPS整点授时、磁扰以及雷电等因素的影响,干扰形态主要表现为尖峰、台阶、扰动等,并总结说明高压直流输电线路的干扰鉴定方式、幅度及干扰时段等。

In order to fully understand the various disturbance factors in the geomagnetic observation environment, improve the ability of observers to identify data anomalies, and ensure the provision of true and effective high-quality observation data, taking the geomagnetic observation at Xuzhuangzi Seismic Station in Tianjin as an example, we analyze the disturbance factors, morphological characteristics and preprocessing methods in geomagnetic observation. The analysis shows that the GM4 fluxgate magnetometer at Xuzhuangzi Seismic Station is mainly influenced by factors, such as high voltage direct current(HVDC) transmission, Metro operation, passing vehicles, ground resistivity power supply, GPS timing, magnetic disturbance, and lightning, which mainly shows as spikes, steps, disturbances;and the interference identification method, amplitude and interference period of HVDC transmission lines are summarized.