国内外重力异常编图进展及重力异常计算方法改进

Progress of gravity anomaly calculation,correction and map compilation

论述了国内外重力异常图,特别是海陆联编重力异常图的编制方法、图面表达以及重力异常计算.介绍了中国地质调查局组织编制的几个层次的地质地球物理系列图中的重力异常图.对我国重力调查规范提出了改进建议.国际上逐渐采用GRS80椭球体作为重力测量和计算的水平及垂直基准,有利于重力数据库的管理和不同来源重力数据间的换算及融合使用.北美重力数据库新标准规定了海区布格改正具体参数和计算方法.我国区域重力调查规范的改进应跟进国际发展动态,研究使用全球通用的参考椭球体作为水平和垂直基准.现行的海洋重力调查规范过于简单,除需增补重要技术规定外,还应对海区布格重力异常计算方法进行研究,特别应对海陆联编重力图的编制方法进行规范.

In this paper, research progress at home and abroad of gravity anomaly calculation and correction, mapping method and means of map presentation for compiling gravity anomaly maps especially the maps covering both land and sea is reviewed. Several rounds of gravity anomaly mapping in geological and geophysical map series launched by China Geological Survey are introduced. Suggestions for improvement on China＇s gravity survey specification are put forward. GRS80 spheroid is adopted internationally as horizontal and vertical datum for gravity survey and calculation, which benefits gravity database management, conversion and integration of different sources of gravity data. New standards of the North American gravity database specify the parameters and method for Bouguer reduction in the sea area. Our regional gravity survey specification should follow up the international development trends. Application of the global reference ellipsoid in gravity calculation should be taken into account. The current marine gravity survey specification is too simple, important technical regulations should be supplemented, complete Bouguer correction should be studied, and the method for gravity mapping over both land and sea should be specified.