FINITE ELEMENT SOLUTION OF THREE-DIMENSIONAL GEOELECTRIC MODELS IN FREQUENCY ELECTROMAGNETIC SOUNDING EXCITED BY A HORIZONTAL ELECTRIC DIPOLE

Absorbing boundary conditions and edge element finite element method are used in 3-D active frequency electromagnetic sounding(including CSAMT) modeling.Benchmark calculation shows that the accuracy of the method is about 3%,which is acceptable for the purpose of analyzing response characteristics of frequency sounding with an electric diploe source for 3-D modeling.Besides,the general variation principle was introduced to solve electromagnetic problem in lossy media.