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作者介绍了广布于鲁西山区的早、中前寒武纪地层:泰山群中的雁翎关组、山草峪组、柳杭组及济宁群的岩石组合、原岩性质、时代及上、下接触关系。泰山群生成年龄通过与新甫山奥长混合花岗岩接触关系及蒙山英云闪长岩的U-Pb法测定的年龄对比,推测它应早于2628Ma。 本文讨论了比泰山群更早的地壳部分——表壳岩的组成成分、演变过程及其上限等问题,并有了一些新认识。对蒙山地区花岗质岩石是地层还是岩体?长期以来一直是悬而未决的问题,通过矿物成分化学成分、分析资料及野外观察,结合镜下鉴定,基本肯定了它是古老的英云闪长岩体。
The author introduces the early and middle Precambrian strata widely distributed in the Luxi mountainous area: the rock assemblages of the Yanlingguan Formation, the Shancaoyu Formation, the Liuhang Formation and the Jining Group in the Taishan Group, the nature and age of the original rock , Under the contact relationship. It is speculated that age of formation of Taishan Group should be earlier than 2628Ma by the age correlation with the contact relationship of the Neo-Fu Shan-Austenitic granite and the U-Pb method of Mengshan-type diorites. This paper discusses the earlier part of the crust than the Taishan Group - the composition of the rock, the evolution process and its upper limit and other issues, and with some new understanding. Whether the granitic rocks in the Mengshan area are strata or rock mass has long been an unresolved issue. Based on the chemical composition of mineral components, analysis data and field observations, combined with the microscopic identification, it is basically confirmed that it is an ancient Yingyun dilatancy Rock mass.