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已有的研究表明,华北克拉通东部的岩石圈地幔在克拉通破坏峰期(早白垩世)时是高度富水的,水化造成的岩石圈强度的显著降低为克拉通破坏提供了前提.古生代以来华北克拉通经历的大洋板块南向、北向和西向的俯冲都可能造成其水化.为了查明造成水化的主导过程,本文对太行山中南段符山早白垩世高镁闪长岩中的橄榄岩包体进行了水含量的测定.数据显示,太行山早白垩世岩石圈地幔的含水量(~40 ppm)远低于华北东部同期的岩石圈地幔(>1000ppm).这些结果直观地表明,华北东部早白垩世岩石圈地幔的高水含量主要是由西向俯冲的太平洋板块造成的.从这个角度来说,华北克拉通破坏的主要动力因素可能是太平洋板块俯冲.
Previous studies have shown that the lithospheric mantle in the eastern part of North China Craton is highly water-rich at the time of the craton pass destruction (Early Cretaceous), and that the significant reduction of lithospheric strength caused by hydration provides the prerequisite for the craton destruction. Since the Paleozoic, the North China Craton experienced the subduction of the oceanic plate in the southward, northward and westward directions, possibly resulting in its hydration.In order to find out the dominant process of hydration, this paper studied the Early Cretaceous high-magnesium diorite The data from the data show that the water content of the Early Cretaceous lithospheric mantle (~ 40 ppm) in the Taihang Mountains is much lower than that of the lithospheric mantle (> 1000 ppm) in the same period of North China. These results are intuitively It is suggested that the high water content of the Early Cretaceous lithospheric mantle in the eastern part of North China is mainly caused by the westward subducting Pacific plateau. From this point of view, the main driving force of the North China craton destruction may be the Pacific plate subduction.