山东鲁山地区新太古代壳源花岗岩锆石SHRIMP U-Pb定年

    SHRIMP U-Pb dating of zircons from Neoarchean crustal derived granites in the Lushan area, Shandong, China

    • 摘要: 山东鲁山地区新太古代壳源花岗岩主要包括粗粒钾长花岗岩、中—粗粒二长花岗岩和斑状二长花岗岩。根据SHRIMP锆石U-Pb定年,其形成时代分别为2525Ma±13Ma 、2517Ma±13Ma和2508Ma±20Ma,且常有残余锆石核存在。它们的形成与华北克拉通新太古代晚期(2.5~2.55Ga)强烈的构造热事件有关,标志着鲁西和华北古陆块克拉通化完成。

       

      Abstract: The Lushan is one of the most famous mountain in Shandong Province, which is located in Zibo City. The crustal derived granites, with many amphibolite and diorite xenoliths, exposed in the Lushan area, were composed of coarse grained alkali-feldspar granite, fine-medium grained monzongranite and phyric monzongranite. The study of zircon SHRIMP U-Pb chronology indicated that the formation ages of the granites in the Lushan area were 2525±13Ma, 2517±13Ma and 2508±20Ma respectively. And zircons from these plutons normally have inherited cores. The granites in the Lushan area were likely to originate from crustal melting. Their formation is closely related to the strong tectonic thermal event between 2.50Ga and 2.55Ga in North China Craton, thus can be regarded as the evidence of cratonization of western Shangdong and North China during Late Neorchean.

       

    /

    返回文章
    返回