瞬变电磁虚拟波场高分辨成像技术研究  

A technology research of high-resolation imaging for the transient electromagnetic pseudo wave field

作　　者：张军 李貅[2] 赵莹 朱宏伟[4] 戚志鹏[2] 

机构地区：[1]中国煤炭科工集团西安研究院,西安710054 [2]长安大学地质工程与测绘学院,西安710054 [3]西安大地测绘工程有限责任公司,西安710054 [4]中国科学院山地灾害与环境研究所,成都610041

出　　处：《地球物理学进展》2011年第3期1077-1084,共8页Progress in Geophysics

基　　金：国家自然科学基金面上项目(40774066);国家自然科学基金重点项目(50539080)联合资助

摘　　要：本文提出了从瞬变电磁场到波场的优化算法.目的是通过对现有波场变换过程进行插值的办法提高波场变换的分辨率,从而为后期数据处理的质量打好坚实的基础.在进行波场反变换的过程中,将正则化算法用于逆变换过程的计算中,通过采用偏差原理和Newton迭代格式选出最优的正则化参数,使得反变换所得到的波场稳定、可靠.解决了积分系数过多而产生的欠定方程组的问题,同时改善了第一类算子方程的不适定性.理论计算表明:变换得到的"波场",不仅满足波动方程,具有传播、反射、透射特征.本文波场数据进行高密度计算,使得在波场变换后得到的数据分辨率更高.通过理论模型的计算,证明该方法对目标体成像更为精确,进而提高瞬变电磁数据处理精度.In this article, we have introduced an optimized calculation method of wave-field transform from the transient electromagnetic field into the pseudo-seismic field. Our purpose is to improve the resolution of wavefield transformation by wavefield transformation of the existing process useing interpolation methods and improve the quality of data processing. During wave-field inverse transformation, the normalization algorithm has been adopted~ optimizing normalized parameters are selected by the deviation theory and the Newton iterative form to make the transformed wave field stable and reliable. By this method we can deal well with the ill-posed problem caused by large amount of integral coefficients and depress the ill-posed problem of the first calculator function. The theoretical calculation indicats that the fictitious wave-field transformed by this method not only satisfies wave functions, but also has the dissemination, the reflection and the transmission. According to the study, calculation of the wave field data already existed through the encryption. After the wave-field transform, the higher resolution of data is abtained. By means of the theoretical model calculation, it is prored that this method is more precise to the goal image formation, then increases the transient electromagnetic data processing precision.

关 键 词：瞬变电磁法 波场变换 正则化算法 

分 类 号：P631[天文地球—地质矿产勘探]