位场数据小子域滤波法处理效果对比与优选

重磁位场数据处理解释的主要任务之一是研究推断地质体的边界位置,而通过对重磁位场数据进行一定方法滤波处理后的相关图件可直观显示地质体的边界。小子域滤波法是众多滤波方法中的一种,前人利用小子域滤波法识别地质体边界位置有较多的研究,目前已有10种类型的小子域滤波法,但是鲜有对10种方法滤波效果的系统研究,给使用者带来诸多不便。因此,设计2组理论模型对比了10种方法的处理效果,并根据试验分析优选了最佳的滤波参数。理论模型与实际资料处理结果表明,滑动形子域滤波法对地质体边界增强的效果最好,且滤波窗口选择5×5数据点、迭代1次即可;对称形子域滤波法在滤除随机噪声的同时能够较好的保持原始异常场的梯度变化特征,滤波窗口选择5×5数据点、迭代2次较好。

The processing effect comparison and optimization of small subdomain filtering method in potential field data

The study of the edge location of the geological body is the most important task in the processing and interpretation of gravity and magnetic potential field data. The results of relevant map can show the geological body''s edge location directly by means of filtering processing with the gravity and magnetic potential field data. Small subdomain filtering is one of the filtering methods, and it has been used by many researchers to recognize the edge location of the geological body. There are 10 kinds of small subdomain filtering methods at present; however, rare studies have analyzed the filtering effect about those methods systematically, and this brings much inconvenience to users. Therefore, the authors designed 2 theoretical models to compare their filtering results and then selected the optimal filtering parameters. The results of theoretical model and field data show that the moving shape small subdomain filtering method has the best effect on enhancing the edge location of the geological body, and the filtering window chooses 5×5 points and 1 iteration. The symmetrical shape small subdomain filtering method can preserve the main gradient direction when filtering the random noise, and the filtering window chooses 5×5 points and 2 iterations.