岩浆岩定量分类方法探讨——以甘肃省西秦岭地区为例

现有岩浆岩定量分类图解,因分类结果不具唯一性,而且不能用于大样本量的分类,备受质疑。本文以聚类分析和判别分析交替使用的方法,对甘肃省西秦岭地区现有523件岩浆岩样本中的11个氧化物测试数据进行定量处理,构建起"甘肃省西秦岭地区岩浆岩(氧化物)定量分类系列模型",该模型将西秦岭地区岩浆岩分为4大类共20小类。与传统的岩浆岩分类方法相比较,定量分类模型不受地质理论和个人主观因素限制,完全由测试数据自身特征和其相关关系所决定,避免了传统分类的种种缺陷,其分类结果更加精准、真实。在区域Au找矿靶区研究过程中,岩浆岩定量分类结果显现出比传统定性分类结果高出11个百分点的判定效果。

Discussion on the method for quantitative classification of magmatic rocks: Taking it's application in West Qinling of Gansu Province for example

Now available diagrammatizing methods for magmatic rock quantitative classification are dispute, not only because the solution isn''t unique, but also it couldn''t be applied to large samples classifying. By both of methods of cluster analysis and discriminant analysis, "Quantitative classifying model for magmatic rocks (oxides) in West Qinling region of Gansu Province" is established in this paper after test data of 523 samples of magmatic rocks with 11 kinds of oxides in this area processed. Magmatic rocks in the area of West Qinling are divided into 20 classes in 4 categories by this model. Compared with the traditional magmatic rock classifying methods, this model for quantitative classification is not limited by any geological theory and individual subjective factors. And the solution is only determined by the characteristics of test data and the correlation, so the classified result is more accurate and true. In the study of regional Au metallogenic target zones prospecting, this model shows a better effect of about 11 percent advantage over traditional classifying methods.