多层等效源方法在地面与航空磁异常数据融合中的应用  

Fusion of Ground and Airborne Magnetic Data Using Multi-Layer Equivalent Source Method

作　　者：高宝龙 胡正旺[1] 李端[1] 杜劲松[1,3] Gao Baolong;Hu Zhengwang;Li Duan;Du Jinsong(Hubei Subsurface Multi-Scale Imaging Key Laboratory,Institute of Geophysics&Geomatics,China University of Geosciences,Wuhan 430074,China;Institute of Geological Survey,Central South Bureau of China Metallurgical Geology Bureau,Wuhan 430080,China;State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]中国地质大学地球物理与空间信息学院,地球内部多尺度成像湖北省重点实验室,湖北武汉430074 [2]中国冶金地质总局中南地质调查院,湖北武汉430080 [3]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《地球科学》2021年第5期1881-1895,共15页Earth Science

基　　金：湖北大冶金牛火山岩盆地1∶2.5万重磁调查项目(Nos.[2016]29,[2017]2,[2018]17);湖北大冶金牛火山岩盆地重磁异常研究及深部找矿预测项目(No.[2018]17);地质过程与矿产资源国家重点实验室自主研究课题(No.MSFGPMR01-4)。

摘　　要：随着地磁场观测数据的不断积累,高效利用观测数据成为亟待解决的问题.以往研究表明,仅对单一观测手段获得的实测数据进行分析与解释,往往很难达到目前解决相关地质问题的精度要求.因为各观测方法获得的地磁场数据集通常在分辨率、精度、高程及覆盖范围方面存在局限性和差异性,造成单一数据集仅能有效表征地磁场某一频段信息的问题.而解决该问题的一种有效途径是数据间的融合.为此,基于等效源方法,提出一种多层等效源技术方案,应用于航空和地面磁测数据融合,提高地面数据插值补空、扩边及航空数据下延的精度.该方法针对观测信息的频谱特征,采用3个位于不同深度的等效源层模拟实测数据;较传统的单层等效源方法,减少了等效源设置的盲目性,增强了观测信息在等效源模型中分配的有序性和结构性.理论实验表明,多层等效源模型设置具有更高的计算精度,航空与地面磁测数据融合可以起到显著的相互丰富及改善的作用.最后,将该方法应用于湖北金牛火山岩盆地航空与地面磁测数据融合,获得了丰富的、平面上规则分布的地磁场数据.With the accumulation of measured magnetic data, it is becoming urgent to use these data efficiently. Previous studies have shown that it is difficult to meet the accuracy requirement for solving geological problems by using the measured data from a single observation method. Because of the limitations and differences in resolution, accuracy, elevation and range of magnetic data obtained by various methods, single dataset can only effectively reflect the information over a certain range of wavelength of magnetic field. An effective way to solve this problem is the fusion of data. Therefore, based on the equivalent source method, a multi-layer equivalent source technology is proposed in this paper, which can be applied to the fusion of ground and airborne magnetic data to improve the accuracy of interpolation, continuation, extension, transformation, et al. According to the spectral characteristics of observation data, three-layer equivalent sources at different depths are used to fit the measured data.Compared with the traditional single-layer equivalent source method, it can reduce the blindness for setting equivalent sources,and improve the ordering and structural performance for allotting observation information into equivalent sources. Synthetic experiment shows that the three-layer model has higher computational accuracy, and data fusion can significantly improve each dataset. Finally, the method is applied to the fusion of ground and airborne magnetic data in Jinniu basin, Hubei, and abundant magnetic data with regular distribution on a plane are obtained.

关 键 词：数据融合 多层等效源 补空 扩边 数据转换 地球物理 

分 类 号：P63I[天文地球—地质矿产勘探]