利用重力异常计算重力梯度的等效源技术  

Deriving the full gravitational gradient tensor from gravity anomaly: an equivalent source technique

作　　者：陈涛[1] 张贵宾[1] CHEN Tao;ZHANG Gui-bin(Department of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球物理与信息技术学院

出　　处：《地球物理学进展》2019年第4期1398-1410,共13页Progress in Geophysics

基　　金：国家重点研发计划(2017YFC0602204-01);国家重点研发计划(2016YFC0600301);中央高校基本科研业务费专项资金联合资助

摘　　要：根据等效源法基本原理,构建了由重力异常计算重力梯度张量的等效源技术.为改善传统层状等效源法计算精度低的问题提出了三维等效源法,并加入正则化提高算法对噪声数据的鲁棒性.针对三维等效源法计算速度慢的问题,通过约束重采样压缩观测数据,实现基于数据约束重采样的三维等效源法.模型试验结果表明,三维等效源法的计算精度比传统的傅里叶变换法和余弦变换法的计算精度高一倍以上.Vinton盐丘地区重力梯度张量的计算结果表明,傅里叶变换法、余弦变换法和三维等效源法的计算结果都和实测重力梯度张量较为一致,且三维等效源法的计算结果受噪声影响更小.Based on the basic principle of the layered equivalent source method,a 3D equivalent source method for deriving the gravitational gradient tensor from gravity anomaly is proposed.The regularized solution is introduced for noisy data.A 3D equivalent source method based on data constrained resampling is finally obtained by compressing the anomaly data for speed up the process.The experiments show that the accuracy of the outcomes of 3D equivalent source method is more than twice as high as that of Fourier transform method and cosine transform method.The results of Vinton salt zone indicate that the outcomes of Fourier transform method,cosine transform method and 3D equivalent source method are consistent with the measured gravitational gradient tensor.At the same time,the 3D equivalent source method is more robust to noise data.

关 键 词：重力梯度张量 三维等效源 重力异常 重采样 

分 类 号：P631[天文地球—地质矿产勘探]