The Cunqian copper polymetallic deposit is an important porphyry —skarn deposit along eastern Qinhang metallogenic belt. The ore —bearing intrusive body comprises biotite plagiogranite porphyry and plagiogranite porphyry, characterized by repeated invasion and calcium-basic rocks. The LA-ICP—MS technique was used in this study, and U—Th-Pb isotopic analysis was made for zircons from the ore—bearing plagioclase granite porphyry, with the petrogenic age obtained being (169.3 ± l.l)Ma. This petrogenic age of the ore — bearing rock body is very close to ages of Dexing granodiorite porphyry, Yinshan quartz porphyry, Lengshuikeng granite porphyry and Tongcun granite-porphyry, suggesting that an event of large—scale magmatic emplacement and mineralization took place in 175-156Ma, which led to the formation of many porphyry-skarn copper polymetallic deposits related to adakite or alkali—calcic granite, and implying that the Qinhang metallogenic belt produced a metallogenic series of porphyry—skarn copper polymetallic deposits under the same magma—dynamic background in this period.%村前铜多金属矿床是产于钦杭成矿带东段的重要的斑岩-矽卡岩矿床,含矿岩体为黑云母斜长花岗斑岩和斜长花岗斑岩,具有多次侵入特点及钙碱性岩石的地球化学特征.本研究采用了LA-ICP-MS技术,首次对含矿的斜长花岗斑岩岩体中的锆石进行了U-Th-Pb同位素分析,获得其成岩年龄为(169.3±1.1 )Ma.这一年龄与钦杭成矿带中德兴花岗闪长斑岩、银山石英斑岩、冷水坑花岗斑岩、桐村花岗斑岩等岩体的年龄十分接近,揭示在钦杭成矿带175～156Ma经历了一次大规模的岩浆侵位与成矿事件,形成了众多与埃达克质或钙碱质花岗岩有关的斑岩-矽卡岩型铜多金属矿床,进一步说明钦杭成矿带在此时期在同一岩浆-动力背景下形成了斑岩-矽卡岩型铜多金属矿成矿系列.
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