非线性共轭梯度(NLCG)算法广泛应用于音频大地电磁法(AMT)二维反演中,并且取得了良好效果.本文以Rodi(2001)提出的大地电磁法二维NLCG反演理论和算法为基础,开展AMT野外数据采集参数(测线长度、点距、频点数)对二维反演效果的影响研究.通过低阻理论模型的试验结果表明:野外数据采集参数的选择应该以探测目标体的规模、深度以及背景电阻率为依据,测线长度应大于目标体宽度和探测深度的两倍以上,异常体上方测点数及探测深度范围内的频点数至少大于三个.
Nonlinear conjugate gradients algorithm (NLCG) is a widespread and effective method of Audio frequency Magnetotelluric (AMT) 2D inversion in practice. This paper carried out the research on effect of acquisition parameters(length of survey line; station distance; frequency points) on AMT 2D inversion results based on NLCG theory and algorithm which Rodi (2001) published. Through the test of typical low resistivity body, the results show that setup of AMT acquisition parameters is based on the scale, exploration depth and background resistivity of the goal body, and length of survey tine is two times as the width and exploration depth of the goal body at least and it is more than three times number of survey station above abnormal body and frequency points in the range of exploration depth.