因子分析在地球化学分区中的应用:以内蒙古石板井地区1∶5万岩屑地球化学测量数据为例

Factor Analysis in the Geochemical Subdivisions: Taking 1∶50 000 Debris Geochemical Survey in the Shibanjing Area of Inner Mongolia as An Example

利用R型因子分析方法,对内蒙古西部石板井地区1∶5万岩屑地球化学测量数据进行了分析,提取出6个具有代表性的因子,绘制出地球化学分区图及因子得分等值线图,并讨论了各分区与其地质背景的对应关系。依据分区结果,结合北山区域成矿背景、工作区地质特征及野外地质调查发现的孔雀石矿化点,确定了Cu-Zn分区是有利的成矿地段,并与志留系公婆泉组变质安山岩有关,90%的孔雀石矿化点位于该分区中。通过对工作区进行地球化学分区,结合各分区中Cu元素含量的统计特征,绘制了Boxplot对比图,分析Cu元素在各分区中的聚集特征,为地球化学勘查提供了找矿方向,确定了成矿有利的地质体。

The authors analyzed the 1∶50 000 debris sample data in the Shibanjing area of Inner Mongolia with the R-mode factor analysis method.Six representative factors were extracted from the data.The geochemical subdivisions have a close relationship with the geological background by making a study of the geochemical subdivision map,factor score map and geological map.Comprehensive studies of the background of regional metallogenic in Beishan area,geological characteristics and malachite mineralization show that the Cu-Zn subdivision which mainly related with the metamorphic andesite of Silurian Gongpoquan Formation being the most favorable metallogenic area.90% of the malachite mineralization was found in these subdivisions.By the study of the statistical characteristics of copper content in all the subdivisions,we have manufactured Boxplot comparison chart and analyzed the aggregation of copper element.In short,the geochemical subdivisions can guide for metallogenic prognosis and favorable geological body.