高级检索

    中吉天山隆升时代对比——裂变径迹年代学证据

    A comparison of uplifting history between Tianshan Mountains in China and Kyrgyz: Insights from fission track chronology

    • 摘要: 中吉天山成矿带境内外天山在成矿时代、矿产种类、矿床规模等多方面存在重大差异。它们的成矿条件基本类似,是否因为保存条件的不同而产生这种差异值得关注。文章对采自吉尔吉斯斯坦北天山(境外西天山)的磷灰石样品进行了裂变径迹测试分析和温度-时间反演模拟研究,表明吉尔吉斯斯坦北天山在中新生代发生了四期抬升剥露作用,分别为晚侏罗世、晚白垩世、始新世和渐新世,且不同区域其抬升剥露史也不相同:晚侏罗世的抬升局限于伊塞克湖南岸的泰尔斯山脉,始新世的抬升主要发生在伊塞克湖南北两侧的泰尔斯山脉和昆格山脉,晚白垩世和渐新世的抬升为吉尔吉斯斯坦北天山整体抬升。与东部境内西天山对比表明,境内西天山整体隆升时间较早,历时较长,有可能隆升剥蚀程度超过境外西天山,从而造成了成矿方面的重大差异。

       

      Abstract: There are considerable differences of the Tianshan metallogenic belt between China and Kyrgyz in such aspects as metallogenic epoch, mineral type and deposit size. As their metallogenic conditions are similar, due attention should be paid to the problem whether the differences are caused by preservation conditions or not. Apatite fission track analysis of Kyrgyz Northern Tianshan and thermal history modeling were performed, and the result shows that there existed four uplifting events from the Mesozoic to Cenozoic, from late Jurassic to late Cretaceous, Eocene and Oligocene, respectively. The late Jurassic uplifting happened in Terskey Range located in the south of Issyk-Kul Lake; the Eocene uplifting happened in Terskey Range and Kungey Range located in the north of Issyk-Kul Lake; the late Cretaceous Issyk-Kul Lake and Oligocene uplifting happened in Kyrgyz Northern Tianshan. By comparing uplifting history of Kyrgyz Northern Tianshan with that of China's Western Tianshan, it is shown that China's Western Tianshan uplifted earlier and lasted for a long time; the extent of exhumation exceeded that of Kyrgyz Northern Tianshan. Maybe it is the reason of the significant differences of mineralization between China and Kyrgyz Tianshan.

       

    /

    返回文章
    返回