地面高精度磁测数据在区域地质填图中应用研究

APPLICATION OF GROUND HIGH-PRECISION MAGNETIC MEASUREMENT IN REGIONAL GEOLOGICAL MAPPING

在前人工作的基础上提出了"多频段的磁异常"的概念.并通过对目前流行的一些滤波方法进行比较,提出使用小波滤波和插值切割法滤波分频的工作思路.探讨了分频段磁异常与地质岩性的关系.认为:①分频以后信息量成倍地增加,读到了许多原始数据(包括常规数据处理)无法读到的信息;②分频提出的信息,不同频率有着不同宏观特征;③不是一种岩性只相关一种频率段异常;④原始数据的结构特点对分频结果起决定性作用;⑤分频有4～5个频段就可以得到许多新的信息;⑥同常规磁异常解释一样,信息提取以后的人工分析是异常解释中非常值得关注的一环;⑦利用插值切割分频的原则是,切割次数是起圆滑作用的因子,因子的大小取决于原始数据的干扰水平(圆滑水平);⑧分频磁异常可以区分不同的岩性.

The concept of multi-frequency magnetic anomaly is introduced on the basis of previous researches.With comparison of some commenly used filtering methods,the idea of frequency-division by wavelet filtering and the interpolation-cut filtering is put forward.The relation between the frequency-divided magnetic anomaly and lithology is discussed.It is concluded that：1）Since the amounts of information double with frequency-dividing,the information that cannot be recognized from primary data will be extracted.2） Different frequencies give different macroscopical characteristics.3）A kind of rock is not correlated to only one frequency of magnetic anomaly.4）The structures of primary data decide the result of frequency-division.5）The frequency-division of four to five bands will get much more new information.6）Similar to the general magnetic anomaly interpretation,the manual analysis is important in anomaly interpretation after information abstracting.7）The times of interpolation-cut filtering is the factor of smooth.8）The frequency-divided magnetic anomaly can distingush differnet kinds of rocks.