【作者】 徐德明； 翟淳； 王国芝；

【Author】 Xu Deming (Yichang Institute of Geology and Mineral Resources,CAGS) Zhai Chun and Wang Guozhi (Chendu Institute of Technology)

【机构】 宜昌地质矿产研究所； 成都理工学院；

【摘要】 信阳地区原龟山组因受简单剪切变形机制作用而被宽的韧性剪切带叠加,构成了一条大型糜棱岩带。各种尺度的变形构造指示剪切变形型式为左旋,指向SE110—130°。矿物变形变晶特征表明,变形过程是一个随温度升高而加强的过程。在该过程中,不仅各主要造岩矿物变形行为依次发生变化,先后从冷加工状态转化为热加工状态,构成了一个递增变形系列,而且物质组分发生了明显的迁移。变形早期由于分异作用和矿物的分解作用造成的岩石中铁镁质成分和长英质成分的分别富集以及Ca和SiO₂等组分的析出,形成了方解石脉、石英脉等赋矿脉体,而在变形后期则由于变质重结晶作用,组分间的调整出现了与早期大致相反的变化。更多还原

【Abstract】 It is showed in this paper that primary Guishan Formation in Xinyang has been modified by ductile shear deformation-metamorphism and superimposed by mylonite zone.As indicated by macroscopic and microscopic structures the deformation manner of the shear zone is sinistral（SE110°- 130°）.Deformation and crystalloblase is of minerals reflect that the deformation is a process of strengthening of strain with rise in temperature. In the process,major minerals were progressively turned from a cold-finished state into a hot working state.Components in the shear zone evidently migrated in this process:in early stage of deformation,femic and felsic materials were enriched,and Ca and SiO₂ were separated to form calcite and quartz veins;in latter stage,the distribution of materials was approximatively opposite to that of early stage.更多还原