岩性分区异常下限衬值法圈定化探异常的优劣:以江苏金山地区为例

Advantages and Disadvantages in Delineating Geochemical Anomalies by Lithologic Zoning Anomaly Based on Lower Limit Contrast Method:A Case Study in Jinshan,Jiangsu Province

笔者以金山地区1∶10000土壤地球化学调查数据为例,利用岩性分区异常下限衬值法圈定异常,通过与传统方法对比,发现岩性分区异常下限衬值法可以有效避免岩性对异常的控制作用,消除背景的影响,圈定的化探异常能提供更有效的找矿信息。通过野外踏勘和异常查证,并对有找矿意义的重点异常进行槽探、钻探验证,发现具工业价值钨矿体和铅锌矿脉。研究表明,利用岩性分区异常下限衬值法在岩性较复杂区确定异常下限的有效性,该方法可以推广使用。

Based on the data of geochemical soil surveys at the scale of 1∶10000 in Jinshan,geochemical anomalies were delineated by lower limit on lithological zone in the study.Compared to traditional methods,it can effectively avoid the control of lithology on the anomaly and eliminate the influence of geological background.Moreover,geochemical anomalies,delineated by lower limit,can provide more effective information in prospecting.Through field exploration and anomaly verification,as well as trenching and drilling verification of key anomalies with prospecting significance,industrial valuable tungsten ore bodies and lead-zinc ore veins were discovered.It suggest that lithology zoning anomaly lower limit contrast method is viable in areas with complex lithology,and therefore can be widely used.