2010.0年中国及邻近地区地磁场

The geomagnetic field in China and neighboring regions for the 2010.0 epoch

本文通过对中国地区地磁场的球冠谐和分析和曲面样条分析,建立了2010.0年代的"中国地磁参考场球冠谐和模型"和"中国地磁参考场曲面样条模型".得到如下结论:"2010.0年代中国地磁参考场球冠谐和模型"描述的各地磁要素空间分布与"2005.0年代中国地磁参考场球冠谐和模型"较相似,但局部略有变化.比如对于磁偏角D和东向分量Y大致可理解为负值区域增强;磁倾角I在我国华北、华南和东北大部大面积正异常区消失了,但在我国西北部大面积的负异常区仍然维持;总强度F和垂直分量Z整体的负异常分布仍然维持,新疆西部局部地区和东南沿海地区局部的正异常分布则略有变化;变化最大的是水平分量H和北向分量X的空间分布,在2010.0年代,东南地区出现了大范围的正异常区,而且在中国北部出现了一条东西条带状的正异常区,似乎可认为是2005.0年代存在于太平洋的正异常区向西移动扩大的结果."2010.0中国地磁参考场曲面样条模型"描述的磁偏角D和东向分量Y相对较为曲折,最显著的异常位于蒙古境内,其次为滇东北地区、东北及华北大部、新疆等地区;磁倾角I和垂直分量Z相对较为平缓,最显著的异常存在于蒙古境内,其次的异常在内蒙满洲里附近;总强度F、水平分量H和北向分量X最为显著的异常位于满洲里附近,其次的主要异常区位于新疆地区、京津附近、滇东北地区.

This work builds on the＂Chinese Geomagnetic Reference Field-spherical cap harmonic model＂and ＂Chinese Geomagnetic Reference Field-surface spline model＂in the 2010.0epoch using analysis with the spherical cap harmonic method and surface spline method.The results show that the spatial distribution of geomagnetic component described by ＂Chinese Geomagnetic Reference Field on 2010.0epoch-spherical cap harmonic model＂are largely similar to those by the＂Chinese Geomagnetic Reference Field on 2005.0epoch-spherical cap harmonic model＂except slight differences in part of the region.For example,the negative territory increased for magnetic declination D and east component Y roughly;positive anomalies disappeared which mostly covered North China,South China and Northeast China,but a large negative area coveringNorthwest China remained for inclination I.Negative anomalies remained on a large scale except slight change in western Xinjiang and southeast coastal regions covered by positive anomalies for total intensity Fand vertical component Z.The biggest change was the spatial distribution of horizontal component H and north component X.Large positive anomalies appeared in southeast China in the 2010.0epoch,and in northern China appeared a positive east-west belt which was like a result of positive anomalies in the Pacific Ocean in the 2005.0epoch moving westward.The＂Chinese Geomagnetic Reference Field on 2010.0epoch-surface spline model＂indicates that the spatial distributions of magnetic declination Dand east component Y were relatively tortuous,and the most obvious anomalies were located in Mongolia,next in the Northeast of Yunnan province,Northeast China,most of North China,and the Xinjiang region.The spatial structure of magnetic inclination I and the vertical component Zis relatively flat,in which the most obvious anomalies existed in Mongolia,followed by those near Manzhouli of Inner Mongolia.The most prominent anomalies of total intensity Fand the horizontal component Hand north component X were present near Manzhouli,followed by those in Xinjiang,Beijing and Tianjin vicinity and northeast of Yunnan province.