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对于阿尔金断裂带中段阿克塞—芒崖地区开展的宏观构造分析、显微构造解析,并结合温压测定与测年分析,证明阿尔金断裂带的早期变形演化是一种韧性走滑剪切变形作用过程,沿断裂带形成了糜棱岩与糜棱状岩石。由变形构造、岩石组构和应变型式判别出与走滑断层作用相伴的中部地壳层次花状构造的存在。构成中部层次花状构造的岩石中同构造变形成因多硅白云母的出现说明韧性变形期间特殊的高围压条件(达0.43GPa),而白色云母(白云母和绢云母)与绿泥石组合指示了较低的温压条件(t:270～350℃;p:0.05～0.43GPa)。断裂带中的异常p/t变化主要归咎于高剪切应力引起的剪切加热与超压效应。依据同变形期矿物(白色云母)~(40)Ar-~(39)Ar记年初步证实早期韧性剪切变形发生于早白垩世(91～89Ma)。
For the macro-structure analysis and microstructure analysis carried out in the middle section of the Altyn Tagh fault in the Aksai-Mangya area, combined with the analysis of the temperature and pressure and the dating, it is proved that the early deformation and evolution of the Altyn Tagh fault zone is a ductile shear- Shear deformation process, formed along the fault mylonite and mylonitic rocks. From the deformation structure, rock structure and strain type, the existence of the crust-shaped flower-shaped structure in the middle of the crust is identified along with the strike-slip faults. The presence of poly-silicate mica, which is the source of the metamorphic deformation in the rocks of the mid-level floral pattern, indicates the special high confining pressure (up to 0.43 GPa) during ductile deformation and the combination of white mica (muscovite and sericite) Indicates a lower temperature and pressure conditions (t: 270 to 350 ° C; p: 0.05 to 0.43 GPa). The abnormal p / t changes in the fault zone are mainly attributed to the shear heating and overpressure effects caused by high shear stress. The early ductile shear deformation occurred in Early Cretaceous (91 ~ 89Ma) according to the record of Ar- ~ (39) Ar in the same deformation period.