摘要
目前我国所采用的重力校正中包括纬度校正、高度校正、中间层校正和布格校正四大校正,这种重力外部校正方法中存在大量的简化假设,以降低计算量,提高运算效率,这种简化假设使得重力校正中存在若干问题:1)由于大地参考椭球与重力正常椭球不一致而引起的纬度误差;2)由于垂直基准面不一致而引起的高程异常;3)地形和中间层校正中密度选择不合理使得重力异常与地质构造背景相左等.随着我国重力勘探力度逐步向西部山区转移和重力勘探精度的提高,这种以大量的简化假设为前提的重力校正方法,便成为制约重力勘探的重要因素.本文对上述问题进行了分析论述,总结了国内外学者针对这些问题所进行的研究,并提出了对未来研究方向的展望,即一种基于"正常空间重力异常"的重力校正方法,这一方法的中心思想在于通过建立大地坐标系参考椭球空间任意一点的正常重力公式,将重力异常直接计算到重力测点上,取消了传统重力校正中的四大校正,从而避免各种校正过程中存在的问题.
The four processes in conventional gravity correction and mid layer correction. For the purpose correction are latitude correction, height correction, terrain of reducing the amount of computation and improving the operation efficiency, the method of gravity external correction has a large number of simplifying assumptions. However,there have some problems in the process of gravity correction casused by the simplifying assumptions, that is： 1） latitude error caused by the difference between geodetic reference ellipsoid and gravity normal ellipsoid~ 2） height anormaly caused by the differ on the vertical datums; 3） unreasonable choice of density in terrain and mid layer correction will make the gravity anormaly conflict with tectonic background. With the gravity exploration efforts in China gradually shift to the western mountains and the accuracy of gravity exploration are improving these days, the conventional gravity correction method based on a large number of simplifying assumptions becomes a important restraining factor of gravity exploration. In the paper, we discussed these problems detailedly and summed up studys of domestic and overseas on these problems. On this basis, we also proposed a prospect for future reserch direction, that is a new gravity correction method based on ＂the normal air gravity anormaly＂, the central idea of the method is compute the gravity anormaly to the gravity measuring point by setting up the normal gravity formulae of an arbitrary point in spaces. Through the method, the four processes in conventional gravity correction are canceled so that the problems in these processes can be avoided.
出处
《地球物理学进展》
CSCD
北大核心
2013年第1期111-120,共10页
Progress in Geophysics
基金
国家重大专项(2008ZX05020-006)
国家863计划项目(2012AA09A2010)
"1:25万青岛幅海洋区域地质调查"(试点)项目(GZH200900501)
关键词
大地参考椭球与正常重力椭球差异
高程异常
离心力位
中间层密度
正常空间重力异常
the difference between geodetic reference ellipsoid and normal gravity ellipsoid, height anomaly, potential of centrifugal force, density of intermediate layer, normal air gravity anomaly
作者简介
骆迪，女，1982年出生，山东济宁人，地球物理专业博士，主要从事重磁资料处理及综合解释方面的研究（E-mial：luodi1982@163．com）
