【摘要】 CSAMT的工作装置和部分探测目标体的三维特性,决定了对CSAMT方法进行三维研究的必要性.在对三维三分量CSAMT方法有限元分析初探的基础上,应用了边界场值不为零的第一类边界条件,并将三维三分量的有限元分析退化为三维单分量来研究.研究结果表明:通过应用边界场值已知的第一类边界条件,缩小了研究范围,提高了计算精度;通过减少研究的分量,使计算速度大大提高;模型的模拟结果很好地说明了电磁场在地下传播中所具有的穿透性和体积效应.以上结果表明本文所用的边界条件有效,三维单分量的研究使计算时间大大减少,从而使本文发展的三维单分量电磁场有限元正演应用于电性介质接近于均匀的三维反演成为可能.更多还原

【Abstract】 It is necessary to study the 3D CSAMT modeling because of the CSAMT configuration and the 3D properties of some survey objects.On basis of the authors’ preliminary3D3C CSAMT modeling work,the first boundary condition with non-zero boundary field values is applied to the finite element method,and at the same time,the research electric fields are reduced from three components to one component.The results show that the research area is reduced through applying the new boundary condition,then the resolution is improved;and the compute speed is accelerated through reducing the research components:the results also show the penetrating property and volume effect of the electromagneticfield propagating in the earth.Therefore the new boundary condition is effective,and it is possible to apply the modeling method to 3D inversion scheme when the medium is vary slowly,because the calculation speed is reduced a lot for modeling 3D1C field.更多还原