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辽西寺儿堡镇新太古代花岗质片麻岩内发育的宏观、微观构造变形特征表明该地区曾遭受了强烈的韧性变形改造。花岗质岩石变形程度在初糜棱岩-糜棱岩之间,岩石经历了SWW向左行剪切作用改造。岩石中石英有限应变测量判别结果表明,构造岩类型为L-S型,为平面应变。岩石的剪应变平均值为1.43,运动学涡度值为0.788~0.829,指示岩石形成于以简单剪切为主的一般剪切变形中。此外,石英颗粒以亚颗粒旋转重结晶和颗粒边界迁移重结晶作用为主,长石颗粒塑性拉长,部分发生膨凸式重结晶作用;石英组构特征(EBSD)揭示石英以中-高温柱面滑移为主;石英颗粒边界具有明显的分形特征,分形维数值为1.151~1.201,指示了中高温变形条件。综合石英、长石的变形行为、石英组构特征以及分形法Kruhl温度计的判别结果,推断辽西寺儿堡镇新太古代花岗质片麻岩经历过480~600℃的中高温变形,其同构造变质相为高绿片岩相-低角闪岩相。花岗质岩石的古差异应力为10.62~12.21 MPa,估算的应变速率为10–11.67~10–13.34 s–1,即缓慢的变形,可能记录早期中高温、低应变速率的韧性变形过程,反映华北克拉通基底中下部地壳变形特征。
The macroscopic and microstructural deformation features of the Neoarchean granitic gneiss in the town of Zhaobosi in western Liaoning show that the area had undergone strong ductile deformation and transformation. The degree of deformation of granitic rocks was between the early mylonite and mylonite, and the rocks underwent SWW left-lateral shearing transformation. The result of finite strain measurement of quartz in rock shows that the tectonic rocks are of L-S type and plane strain. The average shear strain of rock is 1.43 and that of kinematic vorticity is 0.788 ~ 0.829, indicating that the rock was formed in the general shear deformation dominated by simple shear. In addition, the quartz particles are dominated by the spin-recrystallization of the sub-particles and the recrystallization of the grain boundaries. The feldspar particles elongate in plasticity and some of the particles undergo a dextral recrystallization. The quartz structure (EBSD) Surface slip; quartz grain boundary has obvious fractal characteristics, fractal dimension value of 1.151 ~ 1.201, indicating the deformation conditions at high temperature. Synthesizing the deformation behavior of quartz and feldspar, the characteristics of quartz structure and the distinguishing result of fractal Kruhl thermometer, it is inferred that the Neo-Archean granitic gneiss in Erzhongsi Pedabile experienced medium-high temperature deformation of 480-600 ℃, The metamorphic facies is high greenschist facies-low amphibolite facies. The paleo-differential stress of granitic rocks ranges from 10.62 to 12.21 MPa, and the estimated strain rates range from 10-11.67 to 10-13.34 s-1, ie, slow deformation, which may record the ductile deformation process of medium-high temperature and low strain rate in early stage, reflecting Crustal Deformation Characteristics of North China Craton Basement.