| Popis: |
The 2-D electromagnetic E and H fields due to a horizontal infinite line source in air above and on the surface of a conducting halfspace are described in a series formu- lation derived from the addition theorem for the modified Bessel function of the second kind. This low frequency (400Hz) near field geophysical treatment with five subsurface conductivities indicative of metamorphic to sedimentary rocks with the application of boundary conditions at the interface leads to complex coefficient sets of 21 har- monics for the scattered and subsurface fields.The source above the surface with a surface profile centred on it is described.The convergence with harmonic order and dependence on the surface profile is illustrated.For the source on the surface the response is examined fora buried cylinder of radius 20 metres at a depth of 250 metres and with five conductivities representative of sulphide ore bodies. |
