The Electromagnetic Response Modeling of the ELF Method and the Influence of the Ionosphere
详细信息
- 责任者：Li Yong (Institute of Geophysical and Geochemical Exploration ; Chinese Academy of Geological Science ; Langfang 065000 ; China) ; Lin Pinrong
- 刊名：Geophysical and Geochemical Exploration
- 出版年：2010
- 卷期：34(3)
- 关键词：电磁法勘探 ; electromagnetic prospecting
- 页码：p.332-339
- 图表：6 illus., 15 refs.
- 分类号：1600
- issnNo：ISSN1000-8918
- isbnNo：CN11-1906/P
摘要
The Extremely Low Frequency（ELF） method is a new artificial source electromagnetic detecting technique. In this paper, the theory of the ELF method is systematically analyzed. First, in accordance with the studied objects and the problems, the geological structure model and its corresponding mathematical model are built. Then, on the basis of the electromagnetic theory and the selection of a suitable calculation method, the time-harmonic horizontal finitely long grounded wire is set on the crust surface, the mutual coupling of the ionosphere, the air layer and the layered earth are considered, and the general expressions for frequency-domain electromagnetic responses are deduced. These expressions connect electromagnetic response with all parameters such as the conductivity of the ionosphere, and provide theoretical foundation for forward modeling and the feasibility of the ELF method for resource exploration.