The purpose of this study is to clarify the geomorphological characteristics of middle part of Korea. The purpose of this study is to clarify the fault structures in the Chukaryong Rift Valley. The Rift Valley has very significant meaning to interprete the development of Korean structural landforms. But till now the mechanism and processes of the formation of the Rift Valley are not clearly proved IMAGEM is very useful in this study. IMAGEM is developed by the Electromagnetic Instrument, Inc. and it covers $0.001{sim}20,000Hz.$ Form the field survey data, it is certain that the faulted structures exist in the two points of the Rift Valley. But the Rift Valley is too long and braod to check the an evidences of the faulted structures.