地磁正常场的选取与地磁异常场的计算  

Selection of the geomagnetic normal field and calculation of the geomagnetic anomalous field

作　　者：高金田[1] 安振昌[1] 顾左文[1] 韩炜[1] 詹志佳[1] 姚同起[1] 

机构地区：[1]中国地震局地球物理研究所,北京100081

出　　处：《地球物理学报》2005年第1期56-62,共7页Chinese Journal of Geophysics

基　　金：中国科技部社会公益性专项重点项目 (M0 10 72 6A)资助

摘　　要：根据 2 0 0 3年中国地磁观测数据 (包括 135个地磁测点和 35个地磁台 )以及我国邻近地区 38个IGRF计算点的地磁数据 ,计算中国地磁异常场的分布 .选取两种地磁场模型作为地磁正常场 ,一是国际参考地磁场的球谐模型 ,二是中国地磁场泰勒多项式模型 .根据各个测点的地磁异常值 (观测值减去模型计算值 ) ,用球冠谐分析方法计算地磁异常场的球冠谐模型 ,并绘制 2 0 0 3年中国地磁异常图 (ΔD ,ΔI,ΔF ,ΔX ,ΔY ,ΔZ) .分析和讨论了中国地磁异常场 .According to the geomagnetic observational data in China for 2003, including 135 geomagnetic stations and 35 geomagnetic observatories, and the geomagnetic data of 38 IGRF calculated points in China's adjacent regions, the distribution of the geomagnetic anomalous field in China was calculated. The two kinds of geomagnetic models are selected as the geomagnetic normal field: one is the spherical harmonic model of the international geomagnetic reference field, and the other is the Taylor polynomial model of the geomagnetic field in China. Based on the geomagnetic anomaly values (the observed value minus the calculated value of the model) at various stations, the spherical cap harmonic model of the geomagnetic anomalous field was calculated by using the spherical cap harmonic analysis method. The geomagnetic anomaly charts(ΔD, ΔI, ΔF, ΔX, ΔY and ΔZ)in China for 2003 are drawn.The geomagnetic anomalous field in China is analyzed and discussed.

关 键 词：地磁场 地磁正常场 地磁异常场 泰勒多项式方法 球冠谐分析方法 中国地区 

分 类 号：P318[天文地球—固体地球物理学]