成矿元素相态对地球化学异常识别的作用

THE ROLE OF THE PHASE STATE OF METALLOGENIC ELEMENTS IN THE RECOGNITION OF GEOCHEMICAL ANOMALIES

为确定元素相态识别异常的作用,研究了斑岩铜矿Cu和热液铅锌矿床Zn的硫化物相、氧化物相和结合相组成。斑岩铜矿区,Cu以硫化物相和氧化物相为主,(w硫化物相Cu+w氧化物相Cu)/w结合相Cu≥21、(w硫化物相Cu+w氧化物相Cu)/w全量Cu≥96%,是矿化异常的标志。在铅锌矿区,背景区Zn的含量主要是结合相;在w(Zn)≥200×10-6异常地段,Zn主要是以硫化物相(包括氧化物相)存在,(w硫化物相Zn+w氧化物相Zn)/w全量Zn≥87%、(w硫化物相Zn+w氧化物相Zn)/w结合相Zn≥7时是有利的找矿地段,将是指示出露矿和隐伏矿的标志。

In order to determine the role of the phase state of elements in anomaly recognition,the authors studied the compositions of sulfide phase,oxide phase and combination phase of Cu in porphyry copper deposits and Zn in hydrothermal lead-zinc deposits. In the porphyry copper ore district,Cu exists mainly in sulfide phase and oxide phase,with the criteria of the ore-related anomaly being( w sulfide phase Cu + w oxide phase Cu) / w combination phase Cu ≥21、( w sulfide phase Cu + w oxide Cu) / w Cu ≥96%; in the lead-zinc ore district,Zn in the background area mainly exists as combination phase,whereas Zn in the anomalous sectors( w Zn ≥ 200 ×10-6) mainly exists as sulfide phase( including oxide phase),with the segments characterized by( w sulfide phase Zn + w oxide phase Zn) / w Zn ≥87%、( w sulfide phase Zn + w oxide Zn) / w combination phase Zn ≥7 being the favorable ore-prospecting segments and serving as the marks indicating exposed ores or concealed ores.