基于高精度地磁模型与功率谱技术的岩石圈磁场研究  

A study on lithospheric field based on geomagnetic model with high precision and power spectrum

作　　者：冯彦[1] 孙涵[2] 安振昌[3] 毛飞[4] 蒋勇[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]国家卫星气象中心遥感应用试验基地/广西气象减灾研究所,南宁530022 [3]中国科学院地质与地球物理研究所,北京100029 [4]中国气象科学研究院,北京100081

出　　处：《地球物理学进展》2014年第2期478-487,共10页Progress in Geophysics

基　　金：国家自然科学基金(基金号:41174165);公益性行业(气象)科研专项(GYHY200906033);公益性行业(气象)科研专项(GYHY201306073 本文由广西壮族自治区气象局人才工程资助);南京信息工程大学科研启动项目(20110420)联合资助

摘　　要：利用最新的4种高精度全球模型——CM4、NGDC-720、EMM2010与MF7分别建立了中国大陆地区岩石圈磁场，并进行了对比分析，并通过Lowes-Mauersberger功率谱技术展示了常用的10种全球模型的岩石圈磁场功率谱.以EMM2010模型为例，分析表明其岩石圈磁场功率谱变化趋势可以分为5个主要阶段.16～65阶缓慢增加；66～120阶加速增加；121～220阶为平稳阶段，功率达到了最大值；221～670阶缓慢下降；671～719阶缓慢增加.对上述5个阶段的系数绘制并分析了其在中国大陆地区的岩石圈磁场分布，结果表明16～65阶与66～120阶系数构成了岩石圈磁场的主要部分.121～719阶系数对应的磁场非常凌乱，都随着纬度的上升而增强，121～220阶系数对应了岩石圈磁场的极值强度或分布.随着截断阶数的增加，岩石圈磁场的正负分布面积逐渐减小且凌乱.相比CM4模型，EMM2010能表达更多小尺度的磁异常信息.We have compared and analyzed the lithospheric field over Chinese mainland based on four global models, CM4, NGDC720, EMM2010 and MF7 with high precision. The Lowes-Mauersberger power spectra were carried out for 10 global models to check the power spectra of lithospheric magnetic field. Taking EMM2010 as example, results show that the power spectrum is able to be separated into five phases. Degree 16～65, power slightly increases; Degree 66～120, power sharply increases; Degree 121～220, power trends reach the maximum and keep stable; Degree 221～670, power slowly decreased; Degree 671～719, power slightly increased again. After plotting and analyzing the corresponding distributions of lithospheric field based on this five phases, results show that the main parts of lithospheric field are represented by coefficients of degree 16～65 and 66～120. Magnetic field corresponding to degree 121～719 is very orderless, which enhances with increases of latitude, the coefficients of degree 121～220 represent the strength and distribution of maximum values. The areas of positive and negative is becoming smaller and more orderless when degree increasing. EMM2010 express more lithospheric field information with small scale than that of CM4.

关 键 词：岩石圈磁场 Lowes-Mauersberger功率谱 EMM2010 CM4 

分 类 号：P318[天文地球—固体地球物理学]