说明：  大地电磁二维正演程序是电磁法的基础编程，首先设置地电断面然后通过正演模拟电磁场在大地中的传播形式来得到地下地质体的电阻率情况，从而得到地下地质体情况
(Two-dimensional magnetotelluric forward modeling procedure is based programming electromagnetic method, first set the geoelectric section and then through the forward modeling electromagnetic propagation in the earth in the form to get the subsurface resistivity body condition, resulting in underground geological conditions)