Summary
The topographic effect on electromagnetic fields in a three-dimensional conductivity model is investigated using a finite-difference numerical method. The model is that of a conducting block buried in the host Earth beneath a conducting hill. The altitude effect as well as the effect of conductivity of the hill has been studied by comparing the results for the field components at the surface of the hill with those at the surface of a flat half-space. The results indicate that both altitude and the hill conductivity influence the behaviour of the electromagnetic fields. For certain traverses beyond the edge of the block, it is seen that the variations in some field components are mainly due to the topographic effect and that the contribution from the block itself is negligible.
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Ramaswamy, V., Jones, F.W. & Dosso, H.W. A numerical study of the topographic effect on electromagnetic fields in a three-dimensional conductivity model. PAGEOPH 114, 653–662 (1976). https://doi.org/10.1007/BF00875659
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DOI: https://doi.org/10.1007/BF00875659