In two recent papers appearing in Geophysics, d’Erceville and Kunetz (1962) and Rankin (1962) have dealt with the magnetotelluric theory for a plane earth which contains a certain type of vertical fault. In both cases the results depend on a boundary condition which requires the assumption that the normal component of current density vanishes at the surface of the earth. While d’Erceville and Kunetz confine their attention to the region below the surface and thereby avoid explicit mention of the source field, Rankin follows Cagniard (1953) by considering a plane‐polarized electromagnetic wave normally incident on the surface of the earth. In this case, the assumed boundary condition is not correct, as we shall see later; indeed, it actually leads to a contradiction.
High-frequency Properties and Electromagnetic Wave Attenuation for Hexaferrite Composites