A Conducting Permeable Sphere and Cylinder in an Elliptically Polarized Alternating Magnetic Field

Abstract : A formulation is presented for the conducting permeable sphere and cylinder in an elliptically polarized alternating magnetic field. Graphically displayed are the inducing, induced, and total magnetic fields for various values of the ellipticity and azimuth of the inducing ellipse and for various values of the induction number and permeability pertaining to a sphere and a cylinder. Substantial differences can exist between inducing and resultant ellipses, measured in the horizontal plane, in the vicinity of a conductivity inhomogeneity such as a sphere or a cylinder. Additionally, a polarization ellipse appears in any vertical plane in the vicinity of an inhomogeneity. Since substantial changes are introduced in a measured field ellipse by the presence of an inhomogeneity, these effects must be considered when induction studies of the Crust are made. A notation is made of some of the peculiarities to be expected when applying the magnetic variation, magnetotelluric and AFMAG methods. (Author)