CT理论与应用研究Issue(3)：429-437,9.
中心回线式直升机 TEM 资料的电导率-深度成像方法
Conductivity-depth Imaging Algorithm for Central-loop Helicopter TEM
摘要
Abstract
A Conductivity-Depth Imaging (CDI) algorithm is presented for a central-loop helicopter airborne system as an example in this paper, to transform the transient induced electromotive force response data into a conductivity-depth section very quickly. The method aimed at the non-uniqueness problem of the apparent conductivity and the difficulties to obtain the imaging depth in the imaging method, and is successfully developed according to the following steps: firstly, a transformation formula of the data function ( )b s about the conductivity of homogeneous half-space model s is presented, and then a table of the data function relationship with the conductivity is built to search the apparent conductivity value. This method can overcome the problem of the non-unique value of the apparent conductivity. Secondly, the apparent depth is approximated using the depth of the maximum induced electric field in the homogeneous half-space earth, and a data table about apparent conductivity and apparent depth is established to accelerate computing. Finally, the imaging depth is determined based on the depth change of the maximum electric field at the two adjacent delay time and then the CDI result is obtained consequently. The advantage of the method is that its high-efficiency of the table lookup technique can make the real-time CDI possible. Using a table lookup with a large conductivity range from 10-4 S/m to 102 S/m, tests on synthetic data demonstrate that the algorithm does a good job of solving conductive or resistive thin layers and 2D object.关键词
直升机航空瞬变电磁/电导率-深度成像/中心回线/视电导率/视深度Key words
helicopter airborne TEM/conductivity-depth imaging/central-loop/apparent conductivity/apparent depth分类
天文与地球科学引用本文复制引用
毛立峰..中心回线式直升机 TEM 资料的电导率-深度成像方法[J].CT理论与应用研究,2013,(3):429-437,9.基金项目
国家自然科学基金项目（41174092）。 （）
