大地电磁法张量阻抗通用计算公式

General use formula in MT tensor impedance.

在研究大地电磁三维数值模拟时必须解决如何利用数值模拟得到的电、磁场值计算张量阻抗元素的问题。为此 ,本文从理论上系统地推导了适用于复杂地电模型的张量阻抗通用计算公式 ,给出了由数值模拟得到的离散电场、磁场值计算阻抗元素的方法。通过深入分析 ,还得到了每个通用张量阻抗元素计算公式的直观表达式 ,显示出明确的物理意义。例如Zxy表示在源场α·SX和SY的作用下 ,在x方向产生的电场分量加权线性叠加结果和在 y方向产生的磁场分量加权线性叠加结果的比值 。

It needs to solve how to use the tensor impedance elements calculated from the electrical and magnetic fields that are resulted from numerical modeling when studying 3 D MT numerical modeling.For this reason,the paper theoretically and systematically deduced the general calculation formula of tensor impedance that is suitable for complex telluric model and gave the method for impedance elements calculated from the discrete electrical and magnetic fields that are resulted from numerical modeling.Through deep analysis,we also got direct expression of calculation formula for each general tensor impedance element,showing a clear physical meaning.For example,Z xy represents the ratio between weighted linear stack result of electrical field component produced in x direction and weighted linear stack result of magnetic field component produced in y direction,which deepened the knowledge of tensor impedance.