噪声对磁场向下延拓迭代法的计算误差影响分析

磁场向下延拓可以增强数据的分辨率.在现有的向下延拓方法中，迭代法具有较好的计算效果和较大的向下延拓高度.首先介绍了迭代法的基本原理，分析迭代法的特点；然后利用迭代法对不同噪声水平的模型数据和实测数据进行向下延拓计算，研究噪声对迭代法的计算误差影响.通过延拓结果和实际数据比较分析，客观评价了迭代法的计算精度、可靠性及适应性，对推广应用该方法具有实质性意义.

Analysis of noise effect on the calculation error of downward continuation with iteration method

Downward continuation of magnetic field allows to enhance the resolution. Among the available techniques, iteration method for downward continuation of magnetic anomaly has better accuracy and a larger continuation depth. Firstly, the principle of the iteration method is presented, the characteristic of the method is analyzed. The downward continuation computation for model and practical data with noise of different variance is performed by means of iteration method. The accuracy, reliability and stability of iteration method are evaluated based on comparison and analysis of downward continuation results with real magnetic anomaly data. Practicability of iteration method is enhanced.