应用锆石裂变径迹方法研究夹皮沟本区金矿成矿时代

由于锆石裂变径迹封闭温度与吉林省夹皮沟金矿的成矿温度相近,相比其他年代学分析技术,锆石裂变径迹技术具有更好的适用性,其年龄恰可反映金矿成矿年龄,因此本文应用锆石裂变径迹技术探讨夹皮沟本区成矿时代。通过实验获得了8个样品的锆石裂变径迹年龄测试结果,其年龄值在(78±8)~(190±2)Ma之间变化,并可分为2组:190~153 Ma和106~78 Ma。两组年龄揭示了中生代以来区内主成矿时代以及后期叠加成矿年龄,体现出夹皮沟金矿田具有多期次成矿作用。同时,两组年龄还分别体现了太平洋板块与欧亚板块对研究区共同影响的地质事件,并为此提供了年代学的新证据。

Minerogenetic Age of Local Gold-deposit District in Jiapigou Gold Belt,Northeastern China Based on Zi rcon Fission Track Dating

The minerogenetic epoch of local district in Jiapigou gold deposit in the method of zircon fission track was researched. Zircon fission track is the most suitable dating method to study the mineralization ages in Jiapigou, as the metallogenetic temperature of gold deposit in this area is close to the closure temperature of zircon fission track. Therefore, the zircon fission track ages are able to be treated as the metallogenetic ages of gold deposit. In this paper, 8 zircon fission track dating data were achieved and the ages can be divided into two groups: 190.153 Ma and 106.78 Ma. These two groups reveal the main minerogenetic epoch in Mesozoic, as well as the age of later metallogenetic processes. The wide range of zircon fission track ages unveils the existence of multiple period of mineralization. The evidences of fission track ages confirm that the mineralization in Jiapigou gold deposit is intensely influenced by the movement of Pacific plate and Eurasian continent.