基于地面、航磁数据及三维模型的新疆地区岩石圈磁场初步研究  

Preliminary study of lithospheric magnetic field of Xinjiang based on ground,aeromagnetic data and 3D model

作　　者：唐艺嘉 冯彦 TANG YiJia;FENG Yan(NUIST Reading Academy,Nanjing 210044,China;School of Atmospheric Physics Nanjing University of Information Science and Technology,Nanjing 210044,China;State Key Laboratory of Space Weather,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]南京信息工程大学雷丁学院,南京210044 [2]南京信息工程大学大气物理学院,南京210044 [3]中国科学院空间天气学国家重点实验室,北京100190

出　　处：《地球物理学进展》2023年第3期1026-1034,共9页Progress in Geophysics

基　　金：国家自然科学基金(42250103,41974073,41404053);科工局民用航天预研项目(D020308);2023年度中国科学院空间天气学国家重点实验室开放课题;2022年度南京信息工程大学雷丁学院创新创业训练计划联合资助。

摘　　要：基于地面台站及航空磁测数据,我们采用了新开发的三维曲面Spline(3DSS)模型以及区域球谐模型(RSH)建立了高精度的新疆地区三维岩石圈磁场模型,另外通过采用最新的CHAOS-7.5模型数据在100 km高度处进行了模型边界约束,最后将模拟结果与建模数据及CHAOS模型比较验证,结果显示新模型不仅可以反映更多岩石圈磁场的细节,在径向方向可以精细地展现小尺度磁场的衰减变化.新疆地区近地面处的岩石圈磁场主要受到相对浅层磁性岩石的影响,形成感应磁场,其强度随着高度上升而快速衰减,同时受到大尺度磁性基底岩石以及外源磁场的影响而产生强度倒转(强度符号发生变化)的情况.3DSS模型在新疆地区的三个磁异常与当地的地质构造有着很好的相应.通过对比还发现了一些其他全球模型所没有的磁异常特征,如阿尔泰磁异常北部的一些正负条带状的分布,另外还发现了在准噶尔—吐哈盆地东部存在许多小尺度的磁异常.根据磁异常特征推断,该区域是由浅部和深部磁性体相互作用和叠加形成的.Based on the ground and aeromagnetic data,we use the newly developed three-dimensional Surface Spline(3DSS)model and the Regional Spherical Harmonic(RSH)model to establish a three-dimensional lithospheric magnetic field model over Xinjiang with high-precision.In addition,we use the latest CHAOS-7.5 model to constraint the model at the height of 100 km,and finally compare the results with the original data and CHAOS model.It is found that 3DSS model can not only reflect more details of lithospheric magnetic field,but also show the attenuation of small-scale magnetic field in radial direction.Preliminary results also show the lithospheric magnetic field near the ground surface in Xinjiang is mainly affected by relatively shallow magnetic rocks and then to form the induced magnetic field,its intensity attenuates rapidly with the rise of height.At the same time,the intensity reversal(the sign of intensity is switched)is caused by the influence of large-scale magnetic basement rock and external magnetic field.The modeling by 3DSS model in Xinjiang are well corresponding to the local geological structure.Through comparison,some magnetic anomaly features that not exist in other global models are also found,such as thedistribution of some positive and negative strips in the north of Altay magnetic anomaly.In addition,many small-scale magnetic anomalies have been found in the eastern Junggar—Turpan Hami basin,which is,according to the characteristics of anomalies,formed by the interaction and superposition of shallow and deep magnetic bodies.

关 键 词：岩石圈磁场 三维曲面Spline 区域球谐模型 航磁数据 

分 类 号：P318[天文地球—固体地球物理学]