Abstract： Frequency domain electromagnetic sounding is widely used in solid mineral exploration，and it is also one of the commonly used methods in uranium exploration. This method can be used both directly and indirectly prospecting for detecting strata，structure，buried depth of the sand body. Based on the geoelectric model of sandstone type uranium deposits in Yihegaole area of Erlian Basin，the numerical simulation（method）of audio frequency magnetotelluric and broadband magnetotelluric sounding was carried out，and the electromagnetic forward response characteristics and the reverse effect of the two methods were analyzed and compared in the sand body and sand-mud alternating model at different depths. The results showed that the two methods are effective in detecting the sand-mud interbed with relatively high resistance in the shallow part，but fail to distinguish the thin sandstone and mudstone bed. It is difficult to detect the sand mud interbed in the depth. At the same time，the frequency points of broadband magnetotelluric observations are lower，which can detect the deep basement undulation. Through data processing and inversion interpretation of broadband magnetotelluric sounding profiles in Yigaole area of Erlian Basin，sand body distribution and the basement undulations were are also identified. In the exploration of sandstone type uranium deposits in Yihegaole area，the broadband magnetotelluric method is better than the audio magnetotelluric method.
2020, Vol. 36 
