不同水深海底的变化地磁场特征  

The Characteristics of Variable Geomagnetic Field in Ocean Water at Different Depths

作　　者：陆镜辉[1] 冯昭懿 徐行[2] 邱杰[1] LU Jinghui;FENG Zhaoyi;XU Xing;QIU Jie(Guangdong Earthquake Agency,Guangzhou 510070,China;Guangzhou Marine Geological Survey,Guangzhou 510075,China)

机构地区：[1]广东省地震局,广州510070 [2]广州海洋地质调查局,广州510070

出　　处：《华南地震》2020年第3期116-123,共8页South China Journal of Seismology

基　　金：中国地震局监测、预测、科研三结合课题(编号:CEA-JC/3JH-161901);国家重大仪器研发专项(2014YQ100817)联合资助。

摘　　要：认识海洋水体中变化地磁场特征可更好地探索与研究海洋,进而保护海洋资源和环境。选取了布设在南海北部水下740 m、1829 m、2788 m和3788 m深处的四个海底地磁观测站地磁总场值所记录的数据,并收集整理了同时间段位于陆地的广东省肇庆地磁基准台和海南省琼中地磁基准台的观测数据;利用对比陆地和海洋中地磁观测记录在不同磁场环境下的同步观测记录的差异方法 ,分析不同水深环境下的观测记录与陆地之间差异及其主要影响因素。结果表明:在磁静时,变化地磁场海洋中地磁观测记录与陆地台站相比相差不大,而在变化地磁场比较活跃时,两者之间差异较大;在磁扰严重时间段中,水深越深的海陆台之间的差异则更明显;变化地磁场中的高频成分缺少会随水深加大而愈加得以突显。引起变化地磁场记录在海陆之间差异的主要因素是地球外界的变化地磁场与水体中的感应地磁场共同作用所致。Understanding the characteristics of the variable geomagnetic field in ocean water can not only better explore and study the ocean,but also protect marine resources and environment.In this paper,the total geomagnetic field data of four submarine geomagnetic observatories located at depths of 740 m,1829 m,2788 m and 3788 m in the north of the South China Sea are selected,and the observation data of Zhaoqing geomagnetic reference station in Guangdong Province and Qiongzhong geomagnetic reference station in Hainan Province in the same time period are collected.Using the method of comparing the differences between the synchronous data of geomagnetic observation records on land and in the ocean under different magnetic conditions,the diversities between observation records in different water depths and on land and their main influencing factors were analyzed.The results show that the geomagnetic observation records in the ocean do not differ much from those of land stations when the variable geomagnetic field is calmer,and the difference gets obvious when the variable geomagnetic field is more active.During periods of severe magnetic disturbance,the differences are somewhat greater for deeper water depths.The absence of a high-frequency component in the variable geomagnetic field appears to be rising with increasing water depth.The main factor that causes the diversity in the variable geomagnetic field record between land and sea is due to the combination of the variable geomagnetic field outside the Earth and the induced geomagnetic field in the water column.

关 键 词：变化地磁场 海洋 海底地磁观测站 磁扰 观测 

分 类 号：P318.6[天文地球—固体地球物理学]