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米仓山构造带东西向的断裂逆冲兼左旋走滑,西段的韧性变形较强,东段脆性为主。北东向三个主断裂带由北而南逆冲兼左行剪切,早期可能发生脆韧性变形,后期叠加了脆性变形。前震旦系基底岩系变形特征主要表现为透入性流变,碎斑结构和糜棱结构发育,镶嵌构造、S-C组构、带状构造、眼球构造为主,局部偶见“δ”和“σ”旋转碎斑以及矿物鱼。石英颗粒以亚颗粒旋转动态重结晶为主。显微特征反映岩石变形温度相当于绿片岩相。利用Fry法测定石英颗粒三维应变应变强度集中在1.35～1.60之间,显示出从北到南逐渐增强的趋势。Flinn指数K和Nadei-Hossack图解均表明应变类型为近似平面应变的拉长型。运动学涡度分析表明米仓山应变以简单剪切变形作用为主,具有由南向北递增趋势。
The west part of Micangshan tectonic belt is characterized by east-west fracture thrust and left-lateral strike slip. The western part has strong ductile deformation and brittleness in the eastern part. The north-eastward three main faults are cut by north-south thrusting and left-hand row. Early brittle-ductile deformation may occur and brittle deformation will be superimposed in the latter. Deformation features of the former Sinian basement rocks are mainly characterized by pervasive rheology, crustal structure and mylonitial structure, mosaic structure, SC structure, banded structure and eyeball structure, with local occasional “δ” And “σ ” Rotate the shards and mineral fish. Quartz particles to sub-particle rotation dynamic recrystallization-based. Microscopic features reflect the temperature of rock deformation equivalent to the greenschist facies. The Fry method was used to measure the three-dimensional strain strain strength of quartz grains concentrated in the range of 1.35 ~ 1.60, showing a gradual increase trend from north to south. Both the Flinn index K and the Nadei-Hossack plots indicate that the strain type is an elongated type with approximate plane strain. Kinetic analysis of vorticity shows that the strain of Micangshan is dominated by simple shear deformation and has an increasing trend from south to north.