The Definition of Full-domain Apparent Resistivity Based on Air-ground Transient Electromagnetic Data
ZHAO Yue1, WANG Yi-Peng1,2, LI Xiu1
1. College of Geology Engineering and Geomatics, Chang 'an University, Xi'an 710054, China;
2. AVIC Geotechnical Engineering Institute Co., Ltd., Beijing 100098, China
A fast and efficient numerical calculation method of full-domain apparent resistivity for AGTEM has been developed in this paper. We defined the full-domain apparent resistivity using the vertical and horizontal component of time domain magnetic field, in this way we can achieve full space, all time domain apparent resistivity definition. We analyzed thoroughly the Air-ground transient electromagnetic field analytic expression in homogeneous half space, and discovered that the Air-ground time domain response can be expressed in similar polynomial with the central vertical response, use the apparent resistivity translation algorithm, we can achieve full-domain apparent resistivity definition. Model calculation results show that the apparent resistivity definition method does not require iterative, with quicker speed and higher precision. Finally, compared the magnetic field and the voltage based apparent resistivity for resolution of abnormal body.
赵越, 王祎鹏, 李貅. 大定源回线TEM地空系统全域视电阻率定义[J]. 物探与化探, 2015, 39(2): 352-357.
ZHAO Yue, WANG Yi-Peng, LI Xiu. The Definition of Full-domain Apparent Resistivity Based on Air-ground Transient Electromagnetic Data. Geophysical and Geochemical Exploration, 2015, 39(2): 352-357.
[1] Nabighian,Misac N,ed.Electromagnetic methods in applied geophysics[M].SEG Books,1988,2.[2] Verma S K,Mogi T,Allah S A.Response characteristics of GREATEM system considering a half-space model//20th IAGA WG1.2 Workshop on electromagnetic Induction in the earth,2010.[3] Smith R S,Annan A P,McGowan P D.A comparison of data from airborne, semi-airborne, and ground electromagnetic systems[J].Geophysics,2001,66(5):1379-1385.[4] Mogi T,Tanaka Y, Kusunoki K, et al. Development of grounded electrical source airborne transient EM (GREATEM)[J].Exploration Geophysics,1998,29(2):61-64.[5] 嵇艳鞠,王远,徐江,等.无人飞艇长导线源时域地空电磁勘探系统及其应用[J].地球物理学报,2013,56(11):36-40.[6] 殷长春,朴化荣.电磁测深法视电阻率定义问题的研究[J].物探与化探,1991,15(4):290-299.[7] 苏朱刘,胡文宝.中心回线方式瞬变电磁测深虚拟全区视电阻率和一维反演方法[J].石油物探,2002,41(2):216-221.[8] 白登海,Meju M A,卢健,等.时间域瞬变电磁法中心方式全程视电阻率的数值计算[J].地球物理学报,2003,46(5):697-704.[9] 王华军.时间域瞬变电磁法全区视电阻率的平移算法[J].地球物理学报,2008,51(6):1936-1942.[10] 许洋铖,林君,嵇艳鞠,等.航空时间域电磁法回线源有限差分初始场计算[J].电波科学学报,2010(2):259-264.[11] 李貅.瞬变电磁测深的理论与应用[M].西安:陕西科学技术出版社,2002.[12] 朴化荣. 电磁测深法原理[M].北京:地质出版社,1990.[13] Sun H, Li X,Li S,et al.Multi-component and multi-array TEM detection in karst tunnels[J].Journal of Geophysics and Engineering, 2012,9(4):359.[14] Raiche A P.Comparison of apparent resistivity functions for transient electromagnetic methods[J].Geophysics,1983,48(6):787-789.[15] 李金铭.地电场与电法勘探[M].北京:地质出版社,2005.[16] Raiche A P, Spies B R. Coincident loop transient electromagnetic master curves for interpretation of two-layer earths[J].Geophysics,1981,46(1):53-64.
