Regional magnetic anomaly fields:3D Taylor polynomial and surface spline models  

基于三维Taylor多项式和曲面Spline模型的区域磁异常场研究（英文）

作　　者：冯彦[1,2] 蒋勇[1] 姜乙 李正[1] 蒋瑾[1] 刘中微 叶美晨[1] 王弘晟 李秀明[1] 

机构地区：[1]南京信息工程大学数学与统计学院,南京210044 [2]中国科学院空间天气国家重点实验室,北京100080

出　　处：《Applied Geophysics》2016年第1期59-68,218,219,共12页应用地球物理（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.41404053);Special Project for MeteoScientific Research in the Public Interest(No.GYHY201306073);Natural Science Foundation of Jiangsu Province(No.BK20140994),Natural Science Foundation of Higher Education Institutions of Jiangsu Province(No.14KJB170012);Training Program of Innovation and Entrepreneurship for Undergraduates of NUIST(No.201510300178)

摘　　要：We used data from 1960.0,1970.0,1980.0,1990.0,and 2000.0 to study the geomagnetic anomaly field over the Chinese mainland by using the three-dimensional Taylor polynomial（3DTP） and the surface spline（SS） models.To obtain the pure anomaly field,the main field and the induced field of the ionospheric and magnetospheric fields were removed from measured data.We also compared the SS model anomalies and the data obtained with Kriging interpolation（KI）.The geomagnetic anomaly distribution over the mainland was analyzed based on the SS and 3DTP models by transferring all points from 1960.0-1990.0 to 2000.0.The results suggest that the total intensity F anomalies estimated based on the SS and KI for each year are basically consistent in distribution and intensity.The anomalous distributions in the X-,Y-,and Z-direction and F are mainly negative.The 3DTP model anomalies suggest that the intensity in the X-direction increases from-100 nT to 0 nT with longitude,whereas the intensity in the Y-direction decreases from 400 nT to 20 nT with longitude and over the eastern mainland is almost negative.The intensity in the Z-direction and F are very similar and in most areas it is about-50 nT and higher in western Tibet.The SS model anomalies overall reflect the actual distribution of the magnetic field anomalies;however,because of the uneven distribution of measurements,it yields several big anomalies.Owing to the added altitude term,the 3DTP model offers higher precision and is consistent with KI.使用三维Taylor多项式模型,结合曲面Spline模型以及1960.0、1970.0、1980.0、1990.0和2000.0年的实测三要素数据以研究中国大陆地区的地磁异常场。为了获取较为真实可靠的磁异常场,从实测数据中移除了主磁场和电离层磁场和磁层磁场的感应场部分。将两种模型所得到的磁异常与基于实测点和Kriging插值法得到的磁异常相比较。通过将所有测点归算至2000.0年以研究磁异常的整体分布情况。结果显示无论分布还是强度,基于曲面Spline模型和基于Kriging插值法的总强度F的磁异常基本相似。对于整体分布而言,地磁要素X、Y、Z和F的磁异常分布都以负值为主。基于三维模型的磁异常显示随着经度的增加,要素X的强度由-100增加到0nT左右,要素Y的强度从400降低到20nT左右,大陆东部地区基本为负值。要素Z和F的强度变化非常相似,大部分地区都为-50nT左右,西藏西部有一更强的负异常区域。Spline模型可以更好地反映磁异常细节,而实测点的分布不均会产生一些较大的磁异常。考虑了高度因素的三维模型可进行更好的模拟,其与Kriging方法所建的磁异常分布较为一致。

关 键 词：Magnetic anomaly field three-dimensional Taylor polynomial surface spline CM4 

分 类 号：P631.2[天文地球—地质矿产勘探]