摘要
以拟合方差最小为准则,通过点质量法拟合船载重力测量数据,得到点质量大小、埋深等参数。回避点质量法数值求解的不稳定性问题,借鉴移去-恢复技术的思路,利用该参数计算船载重力测量点上的重力异常,并将其在测线上的重力异常中扣除,计算出船载重力残差值。以点质量大小、埋深等参数计算卫星测高重力格网点上重力异常,同样得到测高重力残差值。采用加权最小曲率格网化方法,将船载重力残差值与测高重力残差值格网化,进而恢复由点质量大小、埋深等参数计算格网点处的重力异常,实现卫星测高与船载重力测量数据融合。经国际船载重力测量数据检核,融合后的模型较国际船载重力测量数据的平均偏差在1~2mGal(1Gal=1×10^(-2) m/s^2),标准差约为4mGal。本文的研究方法可为陆地、海岸带区域的多种重力数据的融合、航空重力及卫星重力的向下延拓等问题提供参考。
Using the point mass fit method,the position,size and other parameters of the point mass source are inversed by fitting the shipborne gravity anomaly data with the minimum variance between the point mass model and observed value.Avoiding the instability posed by the point mass method,the shipborne residual gravity anomalies are calculated by using these parameters based on the idea of remove-restore technique.Shipborne gravity residuals can be obtained by minusing the gravity anomaly in the track line.The altimetric residual gravity data are also obtained by using the similar method.Weighted the two residual gravity anomaly by the minimum curvature gridding method,and restored the model gravity anomaly calculated by the point mass size,depth and other parameters,then realized the satellite altimetry and shipborne gravity data fusion.The mean bias is 1~2 mGal and the root mean square is about 4 mGal,which is verified by the international shipborne gravity measurement data.The proposed method can be used as a reference for processing the various gravity data fusion in coastal zone and for satellite gravity downward continuation problem.
作者
柯宝贵
张利明
章传银
党亚民
KE Baogui;ZHANG Liming;ZHANG Chuanyin;DANG Yamin(Chinese Academy of Surveying and Mapping,Beijing 100830,China)
出处
《测绘学报》
EI
CSCD
北大核心
2018年第7期924-929,共6页
Acta Geodaetica et Cartographica Sinica
基金
国家重点研发计划(2016YFB0501702)
国家自然科学基金(41374081
41574004
41674024)
国家基础测绘科技项目(2018KJ0205)~~
