Identification Of The Hydrogeological Structure In Horqin Sandy Based On EH-4 Magnetotelluric Theory

With the development of the geological survey, the demanding of geological exploration work precision has become increasingly high. Combined with traditional geophysical methods which requires a lot of manpower, material and financial resources and a lot of time, so we urgently need to find a new approach to solve these problems. While the new geophysical equipment has also been put into use, the application of EH-4 MT imaging system is one of them, it has a smaller, lighter weight, easy to carry, etc., so compared with other geophysical methods, it has a better adaptability to the exploration environment, therefore it has a broader use. But the main use of the instrument is to find water and prospecting, systematic hydrogeological study the problem is not too much. This thesis used EH-4 MT imaging system in Horqin sand dunes-meadow and white areas to have a study on the thick Quaternary unconfined aquifer hydrogeological problems, which has an important theoretical significance and practical value.In this paper, we use practical application of hydrological and geological survey as an entry point to study the magnetotelluric sounding basic theory and a more detailed introduction of the EH4 Electromagnetic Imaging System. Magnetotelluric. We study its theoretical and the overall workflow more detailed such as:field work methods, data collection and quality control, data extraction and mapping inversion resistivity profile interpretation.Through the EH-4 raw data of the survey area, we get six test lines of EH-4 apparent resistivity section. Combined with the geological data to analysis and interpretation of the apparent resistivity section reasonablely, carved out six aquitard of the survey area, and plotted the results of cross-sectional view of geophysical prospecting. Then we use the existing geological borehole data to test the geophysical prospecting achievements, it proved the overall error of the exploration is less than or equal 4.33%. And the EH-4 has a well application effect in hydrogeology exploration in the Quaternary unconfined aquifer. And then,we used the Voxler to process the resistivity data, to describe the impermeable layer of the study area, plotted-20～-30m,-45～-55m,-85～-95m three sandy clay layer distribution in the space, providing more extensive geological information to improve the accuracy of geological research.