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桐柏—大别造山带剪切带阵列经受长期的应变软化、应变局部化和变形分解作用,形成了一系列构造岩,包括糜棱岩、变晶糜棱岩、半塑性糜棱岩和面理化碎裂岩等。糜棱岩普遍具二相糜棱结构或由相连的弱相基质或层分离强相残斑或布丁所形成的IWL(Interconnected weak matrix or layers)结构。构造岩中显微构造各式各样,并具一定的组合形式和演化规律,反映了不同环境下主导变形机制的多样性及变形机制间转换的规律性。代表性剪切带岩石化学成分变异的研究表明,除流体流动外,体积亏损是造成某些组分,尤其是一些不活动组分,如钛、磷、锆、钒、钇等相对富集的主导因素,并由化学成分的变异和质量平衡计算,求出了该剪切带的体积亏损率以及流体/岩石值。较大的体积亏损和大量渗透体的存在,对剪切带的化学行为和流变行为都有着重要的影响作用。
The Tongbai-Dabie orogenic belt shear-band array undergoes long-term strain softening, strain localization and deformation decomposition, forming a series of tectonic rocks including mylonites, metamorphic mylonites, semi-plastic mylonites and facies Physical and chemical crushing rock. Mylonites generally have a two-phase mylonite structure or an IWL (Interconnected weak matrix or layers) structure formed by the separation of strongly-associated spots or puddings by a connected weak phase matrix or layer. The microstructures in the tectonic rocks are various and have certain combinations and evolutions, which reflect the diversity of dominant deformation mechanisms and the regularities of transformation between deformation mechanisms in different environments. The study on the chemical composition variation of representative shear zone rocks shows that, in addition to fluid flow, the volume loss is caused by the relative enrichment of some components, especially some inactive components such as titanium, phosphorus, zirconium, vanadium and yttrium Dominated by the chemical composition of the variation and mass balance calculation, calculated the volume loss rate of the shear zone and the fluid / rock value. The large volume loss and the presence of a large amount of infiltration body have an important influence on the chemical behavior and rheological behavior of the shear zone.