DEM网格间距对重力远区地改精度的影响及效果  

The impact and effect of DEM grid spacing on the accuracy of gravity remote topographic correction

作　　者：李忠平[1,2] 戴广凯[3] 张茂辉 LI Zhong-Ping;DAI Guang-Kai;ZHANG Mao-Hui(School of Geophysics and space information,China University of Geosciences(Wuhan),Wuhan 430074,China;Zhengyuan Geology&Exploration Institute of Shandong,Bureau of China Metallurgy and Geology,Jinan 250014,China;Shandong Institute of Geological Survey,Jinan 250013,China;School of Geophysics and Space Information,China University of GeosciencesOcean University of China,Qingdao 266100,China)

机构地区：[1]中国地质大学(武汉)地球物理与空间信息学院,湖北武汉430074 [2]中国冶金地质总局山东正元地质勘查院,山东济南250014 [3]山东省地质调查院,山东济南250013 [4]中国海洋大学工程学院,山东青岛266100

出　　处：《物探与化探》2020年第6期1399-1407,共9页Geophysical and Geochemical Exploration

基　　金：中国地质调查局地质矿产调查专项(FZK2016-4-166)。

摘　　要：1∶5万重力远区地改一般由测区的1∶5万DEM高程模型改正获得。1∶5万DEM可按不同网格间距拼接而成,不同网格间距对应了不同的地改精度;RGIS是由自带高程库参与计算,完成测区1∶5万重力远区地改。本文以山东省栖霞市臧家庄幅1∶5万重力远Ⅰ区(2~20 km)地改为例,通过采用25、50、100、200 m四种网格节点距进行了1∶5万DEM数据拼接和改进的双线性插值法重力远Ⅰ区地改、均方误差计算,并与RGIS自带高程库重力远Ⅰ区地改均方误差比较分析,证实基于1∶5万DEM高程模型重力远Ⅰ区地改精度优于RGIS自带高程库重力远Ⅰ区地改精度。基于DEM改进的双线性插值法远区地改布格重力异常和高程相关度更高,对线性构造和地层、岩体的边界的识别精度高。The 1∶50000 gravity far area terrain correction is generally obtained from the 1∶50000 DEM elevation model correction in the survey area.1∶50000 DEM can be spliced according to different grid spacings,which correspond to different terrain correction accuracies;RGIS is calculated by its own elevation database,and the topographic correction of 1∶50000 gravity far area in the survey area is completed.The authors chose the 1∶50000 gravity remote area I(2~20 km)land reform of Zangjiazhuang area in Qixia City,Shandong Province,as an example.Through the use of 25,50,100,200 m four grid node spacings for 1∶50000 DEM data splicing and the use of the improved bilinear interpolation method,the authors calculated the terrain correction and mean square error in the far area I of gravity.Compared with the terrain correction mean square error of gravity far area I of RGIS own elevation reservoir,it is confirmed that the terrain correction accuracy of gravity far-Ⅰarea based on 1∶50000 DEM elevation model is better than that of gravity far-Ⅰarea with RGIS.

关 键 词：重力远区地形改正 DEM网格间距 地形改正精度 改进的双线性插值 

分 类 号：P631[天文地球—地质矿产勘探]