基于实码加速遗传算法的投影寻踪模型在圈定水系沉积物地球化学异常中的应用——以湖南某铅锌矿床为例  

The application of projection pursuit model combined with RAGA to identifying stream sediment geochemical anomalies: A case study of a Zn-Pb deposit in Hunan Province

作　　者：郝立波[1] 田密[1] 赵新运[1] 赵昕[1] 张瑞森[1] 谷雪[1] 

机构地区：[1]吉林大学地球探测科学与技术学院,吉林长春130026

出　　处：《物探与化探》2016年第6期1151-1156,共6页Geophysical and Geochemical Exploration

基　　金：湖南省国土资源信息中心地球化学找矿信息挖掘服务(湘财采计[2014D]0326号)

摘　　要：单纯利用成矿元素圈定异常,可能会出现异常与已知矿床不对应的现象。矿化过程伴随着某些微量元素的富集,同时也伴随着一些元素的贫化,将成矿元素与富集及贫化微量元素相结合,可以大大提高地球化学找矿的效果。利用基于实码加速遗传算法的投影寻踪模型将高维数据投影到一维子空间进行分析,既可以得到投影值的大小又可以获得每个元素的权重,在不损失重要信息的同时又可以剔除噪声数据,具有较好的稳健性。通过某铅锌矿床实例研究,发现单纯应用成矿元素圈定异常,会出现某些异常区没有矿床,或者某些矿床并无对应异常的情况,而利用投影值圈定的异常范围与已知矿床吻合得更好,说明投影寻踪方法的分析结果更加突出了一些与成矿有利部位的异常,减少了异常查证面积而没有丢失异常信息。因此,将多元素信息结合,利用基于实码加速遗传算法的投影寻踪模型能够有效处理高维数据并获取重要的信息,能够比较准确地圈定异常区域。The anomalies composed of ore-forming elements may not correspond with the known deposits. Some trace elements are accu-mulated during the mineralization process whereas some elements are depleted. The combination of the ore-forming elements and other trace elements influenced by mineralization may enhance the effect of geochemical exploration. In this study, high-dimensional data were converted into one-dimensional data for analysis by projection pursuit model based on RAGA. The projection values and the weights of elements can be calculated by this method. Moreover, important information will not be lost and the noise data will be dele-ted. In addition, this method is very robust. By the case study of a Pb-Zn deposit, it is found that some deposits are not in anomaly are-as or some deposits do not have corresponding anomalies. However, the ranges of anomalies obtained by this method correspond with the known deposits better. The results of PPC highlights the anomalies associated with the known deposits and, moreover, the anomaly in-formation has not been lost. The projection pursuit model combined with RAGA by using multiple elements performs better on high di-mensional data and identifies stream sediment geochemical anomalies effectively and accurately.

关 键 词：水系沉积物 投影寻踪模型 地球化学异常 微量元素 矿床 

分 类 号：P632[天文地球—地质矿产勘探]