云南个旧老厂矿田东部大比例尺构造地球化学特征及找矿预测

Large scale tectonic geochemical characteristics and prospecting prediction in eastern Laochang orefield,Gejiu,Yunnan Province

老厂矿田是个旧锡铜多金属矿集区的重要组成部分,半个世纪以来,随着资源的消耗,老厂矿田已跨入资源危机行列。为缓解个旧锡矿矿产资源紧缺局面,延长矿山寿命,本文在对研究区开展1∶10000构造地球化学测量的基础上,分析总结12种元素的地球化学特征,运用相关分析确定出元素相关关系,利用含量—面积(C-A)分形法确定异常下限,圈定异常范围,进而划分找矿远景区。结果表明:12种元素的离散、分异程度均较大,具有不同程度富集,其中Pb、Sn、Cu、Bi、As、Cd等为老厂东部主要成矿元素;Sn、Cu与Ag、Sb、Zn、Pb、As、Bi的相关性较好,与成矿关系密切;圈定的5处找矿远景区,经工程验证发现锡铜矿体,说明该地区应用构造地球化学方法可以有效地为找矿工作提供科学依据。

In the past half a century,with the consumption of resources,the Laochang orefield has entered the rank of resource crisis.In order to alleviate the shortage of mineral resources in the Gejiu tin deposit and prolong the life of the mine,the authors,on the basis of 1∶10000 tectonic geochemical survey in the study area,analyzed and summarized the geochemical characteristics of 12 elements,used correlation analysis to determine the correlation of elements,used content-area(C-A)fractal method to determine the anomaly threshold,delineated the abnormal range,and then divided the prospecting area.The results show that the 12 elements are highly dispersed,differentiated and enriched in different degrees,among which Pb,Sn,Cu,Bi,As and Cd are the main ore-forming elements in the eastern part of Laochang,Sn and Cu elements have good correlation with Ag,Sb,Zn,Pb,As and Bi elements,and are closely related to mineralization;five prospecting area were delineated,and tin-copper orebodies were found through engineering verification,which shows that the application of tectonic geochemical method in this area can effectively provide scientific basis for the prospecting work.