国家科技基础条件平台
  • 你好,请
  • 登录
    • logotext
    SHRIMP Zircon U-Pb Dating of the Tongshi Magmatic Comlex in Western Shandong and Its Geological Implications [查看] HUHuabin、MAOJingwen、LIUDunyi、NIUShuyin、WANGYanbin、LIYongfeng、SHIRuruo
    Abstract The SHRIMP U-Pb zircon dating result of the Tongshi magmatic complex in western Shandong is presented in this paper. The Tongshi magmatic complex comprises fine-grained porphyritic diorite and syenitic porphyry. Eighteen analyses for fine-grained porphyritic diorite gave two concordia ages, in which ten analyses constitute the young age group,giving 206Pb/238U ages ranging from 167.9 Ma to 183 Ma with a weighted mean age of 175.7 ± 3.8 Ma, and the other eight yielded 207Pb/206Pb ages of 2502 Ma to 2554 Ma with a weighted mean 2518 ± 11 Ma. Two analyses for syenitic porphyry gave ages of 2485 Ma and 2512 Ma, respectively. The age of 175.7 ± 3.8 Ma indicates that the crystallization of the Tongshi magmatic complex occurred in the Middle Jurassic, whereas that of 2518 ± 11 Ma is interpreted as the age of inherited magmatic zircons in the Neoarchean Wutai period.
    © BJSHRIMP 2013 - bjshrimp.cn