二维大地电磁尖锐边界反演研究(英文)  

A STUDY ON 2D MAGNETOTELLURIC SHARP BOUNDARY INVERSION

作　　者：张罗磊[1] 于鹏[1] 王家林[1] 吴健生[1] 陈晓[1] 李洋[1] 

机构地区：[1]同济大学海洋地质国家重点实验室,上海200092

出　　处：《地球物理学报》2010年第3期631-637,共7页Chinese Journal of Geophysics

基　　金：National High Technology Research and Development Porject (863)(2008AA093001);National Science and Technology Major Project (2008ZX05005-005-010HZ);the National Natural Science Foundation of China (40674063);National Key Foundation Research Development Project (973)(2007CB411706-02)&(2007CB411702);Project (MG20080203) of State Key Laboratory of Marine Geology, Tongji University

摘　　要：尖锐边界反演是大地电磁及其他地球物理反演中的一个较难解决的问题,目前有不少专家正对这方面进行研究.我们在分析了Zhdanov(2004)提出的基于最小支撑泛函聚焦反演方法的基础上,在目标函数中引入对角梯度支撑以改善倾斜电性分界面的反演效果.同时,为了提高计算效率,本文还使用互易定义计算灵敏度矩阵及使用正则化共轭梯度法优化目标函数.通过模型试验并与未引入对角梯度支撑的反演结果进行了比较,表明本文的方法反演效果更好而且算法稳定和实用.Sharp boundary inversion is a relatively difficult problem in magnetotelluric （MT） and other geophysical inversion, which has been studied by many researchers. We analyze the focusing inversion which is based on the minimum gradient support functional provided by Zhdanov, M. S. （2004）, and introduce a diagonal gradient support into the objective function to improve the presentation of oblique geo-electrical interface. Certain models are designed to test this method in the paper. Compared with the results inversed by the focusing inversion without diagonal gradient support, the shape of oblique geo-eiectrical interface really displays better, this new algorithm is also proved to be stable and practical. Meanwhile, in order to improve the computing efficiency, reciprocity theorem is used to calculate sensitivity matrix, and regularized conjugate gradient method is introduced to solve the objective functional minimum.

关 键 词：大地电磁 聚焦反演 尖锐边界 梯度支撑 共轭梯度 

分 类 号：P631[天文地球—地质矿产勘探]