Electrical characteristics of typical loess sections in northern Shaanxi and the relevant geoelectric model
ZHANG Song1, 2, LIU Zhan2, XU Kai-Jun2, LI Tie-Ming3, CHEN Xiao-Hong2, YAN Xiang-Xiang2, ZHU Jiong-Jun2
1.Second Crust Monitoring and Application Center,CEA,Xi'an 710054,China; 2.School of Geosciences,China University of Petroleum (East China), Qingdao 266580,China; 3.Institute of Geology,CEA,Beijing 100029,China
Abstract：Using the permittivity and resistivity data of 239 measuring points which were collected from seven typical loess profiles in Yanchang, Luochuan and Baoji area of northern Shaanxi, the authors summarized the dielectric and resistivity characteristics of loess, and found that the loess layer and the red soil layer could be significantly distinguished according to their electrical properties. Then the relationship and influence factors of electrical parameters of loess in northern Shaanxi were discussed. With the most detailed Chang-10-well loess section in Yanchang area as an example, the electrical characterization and description of the Chang-10-well loess section were described in detail. In addition, the following three problems were preliminarily explored: the theoretical feasibility for electromagnetic method such as GPR(ground penetrating radar) to distinguish clay layer in the Loess Tableland; whether it's necessary to eliminate the influence of moisture content on electrical parameters; the establishment of a scientific earth-electricity model. The results obtained by the authors provide the theoretical foundation of loess electrical characteristics and the basis of interpretation for electromagnetic profiles and earth-electricity model of loess so as to probe into electromagnetic methods such as GPR(ground penetrating radar) for distinguishing clay layer in the Loess Tableland.
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