CHAOS-6模型描述的中国地区地磁长期变化及误差分析  

Geomagnetic Secular Variation in China Described by CHAOS-6 Model and its Error Analysis

作　　者：王振东[1] 顾左文[1] 陈斌[1] 王粲[1] 袁洁浩[1] WANG Zhendong GU Zuowen CHEN Bin WANG Can YUAN Jiehao(Institute of Geophysics, China Earthquake Administration, Beijing 100081, China)

机构地区：[1]中国地震局地球物理研究所,北京100081

出　　处：《地震研究》2017年第3期404-410,共7页Journal of Seismological Research

基　　金：中国地震局地球物理研究所基本科研业务费专项"与地下应力状态相关的局部岩石圈磁场变化实验研究"(DQJB16B04)资助

摘　　要：根据CHAOS-6模型,计算了2015年中国地区28个地磁台站的地磁年度变化以及2008.0—2016.5年成都、格尔木、兰州、泰安和通海5个地磁台站的地磁长期变化。分析比较了地磁台站实际观测值与CHAOS-6模型计算值之间的差异,得到两者差值的均值及均方误差。结果表明:CHAOS-6模型描述的中国地区地磁长期变化与地磁台站实际观测的地磁长期变化趋势基本一致,但存在一定的差异,28个台站的磁偏角(D)、磁倾角(I)、地磁总强度(F)、北向分量(X)、东向分量(Y)、水平分量(H)、垂直分量(Z)差值的均值和均方误差的平均值分别为-0.9'/1.7',-29.3'/0.8',-116.3 nT/10.2 nT,264.7 nT/13.6 nT,-27.7 nT/15.0 nT,265.2 nT/13.7 nT,-356.9 nT/8.0 nT。因此,在使用CHAOS-6模型研究中国地区区域问题时,应充分考虑模型的误差大小。According to the CHAOS - 6 model, the annual changes of geomagnetic at 28 observations located in China in 2015 and the geomagnetic secular variations at CDP, GLM, LZH, TAA and TILl observations in 2008.0-- 2016.5 were calculated. The differences between the geomagnetic data of practical observations and those calcu- lated by the CHAOS -6 model were analyzed. The mean differences and the mean square root cr were ob- tained. The results show that the trend of the geomagnetic secular variation in China described by the CHAOS - 6 model is basically consistent with those at observations, but there are some differences. The mean of the differ- ence and the mean square root are -0.9＇/1.7＇ and -29.3＇/0. 8＇ for geomagnetic declination （D） and inclina- tion （I） respectively; and the mean of the difference and the mean square root are - 116.3 nT/10. 2 nT, 264. 7 nT/13.6 nT, -27.7 nT/15.0 nT, 265.2 nT/13.7 nT and -356.9 nT/8.0 nT for total intensity （F）, northern component （X）, eastern component （Y）, horizontal component （H） and vertical component （Z）, respectively at 28 observations. The main reason for the error of the geomagnetic secular variation in China de- scribed by the CHAOS -6 model is that the regional and local magnetic anomalies in China, while the CHAOS -6 is a model of global geomagnetic field. The error of the CHAOS -6 model should be fully considered when we use it to study the regional problems in China.

关 键 词：CHAOS模型 地磁年度变化 地磁长期变化 地磁台站 

分 类 号：P318[天文地球—固体地球物理学]