The magnetotelluric method is an electromagnetic method which uses measurements of the natural magnetic and electric fields at the surface of the earth to determine the distribution of electric resistivity within the Earth. This property is important in deep structures, petroleum and geothermal exploration. Because electrical resistivity depends directly on: porosity, permeability, pore fluid saturation, temperature and the presence of conducting ore materials such as graphite and sulphides. MT is used to explore the earth’s crust and the upper mantle especially in tectonically active regions volcanic and earthquakes.