摘要
本文研究了基于径向基函数融合航空重力梯度张量数据重建高分辨率区域重力场模型的方法.针对传统勒让德级数展开方法存在求解复杂度高、计算效率低的局限性,以泊松小波基函数为例构建了基函数及其一阶、二阶偏导数快速递推计算的封闭解析表达式,建立了融合全张量重力梯度数据的快速建模方法.以加拿大圣乔治海湾为例,采用全张量航空重力梯度数据恢复了格网分辨率约为0.5 km的陆海统一重力场模型,量化了采用不同重力梯度分量对于建模的贡献,并利用实测地面重力数据检核了采用航空重力梯度恢复的重力场模型.数值分析表明,仅采用单一重力梯度分量建模时,利用垂直分量建模对于重力场重建的贡献较大,且基于垂直分量求解模型的精度较高.此外,相比于仅采用单一重力梯度分量建模的结果,联合多个梯度分量建模能提升重力场模型的精度.较之于已有全球高阶重力场模型和测高重力异常数据,联合航空重力梯度数据求解的局部重力场模型在短波段的精度有显著提高.
This research studies the method for high-resolution regional gravity field modeling from airborne gravity gradient tensor(GGT)based on radial basis functions.Considering the heavy computational load and numerical inefficiency of the traditionally used Legendre polynomial expansion,a fast modeling approach for regional gravity field recovery from the full GGT is proposed.We use Poisson wavelets as an example,and the analytical expressions of Poisson wavelets and the associated first-and second-order partial derivatives are recursively deduced,to link the full GGT to the representation of regional gravity field.By combining the full airborne GGT,we model the regional gravity field model with a resolution of 0.5 km over the St.George′s Bay in Canada,and quantify the effects on the gravity field recovery using individual components of GGT.The results show that the solution computed from the vertical component of airborne GGT provides the best quality when a single component is used.Moreover,the incorporation of multiple components of airborne GGT magnifies the gravity anomalies and further improves the quality of the local gravity field,compared with the solutions computed using single components.By combining the full airborne GGT,the derived regional gravity field model has improved accuracy in short wavelengths,compared to the recently released high-degree global geopotential models and satellite altimetric gravity data.
作者
吴怿昊
罗志才
汪海洪
何秀凤
杨萌
WU YiHao;LUO ZhiCai;WANG HaiHong;HE XiuFeng;YAGN Meng(School of Earth Sciences and Engineering,Hohai University,Nanjing 211100,China;National Gravitation Laboratory,Institute of Geophysics,MOE Key Laboratory of Fundamental Physical Quantities Measurement,School of Physics,Huazhong University of Science and Technology,Wuhan 430071,China;School of Geodesy and Geomatics,Wuhan University,Wuhan 430079,China;School of Geospatial Engineering and Science,Sun Yat-Sen University,Zhuhai Guangdong 519082,China)
出处
《地球物理学报》
2025年第3期769-787,共19页
Chinese Journal of Geophysics
基金
国家自然科学基金(42374099,42004008,U23A2028)
江苏省自然科学基金青年基金(BK20190498)资助。
关键词
航空重力梯度测量
全张量重力梯度数据
高分辨率重力场建模
泊松小波基函数
快速建模方法
Airborne gradiometry
Full gravity gradient tensor
High-resolution gravity field modeling
Poisson wavelet radial basis functions
Fast modeling approach
