晋宁运动和震旦系有关问题

    PROBLEMS RELATED TO THE JINNING MOVEMENT AND THE SINIAN SYSTEM

    • 摘要: 运用板块构造理论,提出晋宁运动可能代表着扬子古陆块与东南古陆块碰撞造山事件,它发生在中元古代末期至晚元古代早期,经历了大约200Ma。震旦系下部莲沱组发育在晋宁夷平基底之上,是海侵初期形成的陆缘移地滨岸相沉积,底界是一个穿时面。在中元古界变质岩系与震旦系之间局部地段发育有晋宁造山期磨拉石沉积,地层时代归属青白口系。板溪群亦为晋宁夷平基底之上的海侵沉积,但其底界可能穿时到青白口系之中。

       

      Abstract: From a plate tectonic perspective, this paper proposes that the Jinning movement might repiesent an orogenic event caused by the collision of the Yangtze block and the Southeast block. It occurred from the terminal Middle Proterozoic to early Late Proterozoic and lasted for about 200 Ma. The Lower Sinrian Liantuo Formation, developed on the Jinningian planation basement, is epicontinental littoral deposits formed at the initial stage of transgression, and its base is a diachronous surface. There occur Jinningian orogenic molasse deposits in local areas between the Middle Proterozoic metamorphic rock series and the Sinian, which are assigned to the Qingbaikou System. The Banxi Group is also marked by tiangressive deposits above the Jinningian planation basement, but its base might cut into the Qingbaikou System.

       

    /

    返回文章
    返回