The particularity and perfect arcuate geometry of the Daba Mountain, which is located between Yangtze Plate and Qinling Orogenic Belt, have drawn the attentions of many geologists. In order to extract information about the collision between the Yangtze and North China blocks and intracontinental orogeny, we studied the rock microtectonics in the Shiquan-Ankang Fault (SAF) and the Chengkou-Fangxian Fault (CFF). Mineral fish, pressure shadow and porphyroclast system are well developed in the SAF. The kinematic indicators show obvious dextral movements in the thin sections. Quartz grains have undulating and bland extinction foliation. Subgrain rotates played important roles in dynamical recrystallization. All indications imply that the ductile deformation took place in the SAF. The pole density of quartz c axial mostly locate at the margin of the circle, and the others locate at the centre of the circle, indicating the important impact of basal slide system and the hombic slide system. The higher than 1 Flinn index suggests that the deformation was constriction ellipsoid in the SAF. But the thin sections of the CFF have weak porphyroclast system, preferential orientation, and undulose extinction. All the features mentioned above indicate that the deformation was brittle in the CFF. The pole density of quartz c axial on the marginal of circle suggests that the basal slide was the main slide system. The lower than 1 Flinn index suggests that the deformation was flattening ellipsoid in the SAF. It can be inferred that the deformation and metamorphism in the Daba Mountain occurred under middle to low temperature, equal to greenschist facies, but the South Daba Mountain has lower deformation intensity and metamorphism temperature than that of the North Daba Mountain. The arcuate Dabashan thrust-and-fold belt thrusted toward southwest by NE compressive stress and then right-lateral motion along the CFF under the NNE compressive stress field.%位于扬子板块北缘和秦岭造山带南缘的大巴山构造带以其独特的弧形特征吸引着众多学者的广泛关注。本文主要从显微组构方面对石泉–安康断裂和城口–房县断裂附近的样品进行了详细分析和对比，旨在为扬子与华北板块穿时斜向碰撞及陆内造山作用提供一些基础信息。大巴山石泉–安康断裂带两侧样品主要发育矿物鱼、压力影、旋转碎(残)斑系，运动学指示标志以右旋为主，石英颗粒呈波状消光和带状消光，定向拉伸明显，以亚颗粒旋转(SGR)动态重结晶为主，具有韧性变形特征，石英 c 轴点极密大多数分布边缘，少数位于中心，指示了底面滑移为主或底面滑移与菱面滑移共同作用， Flinn指数K值大于1表明应变样式为拉长型椭球体。城口–房县断裂带东段样品石英碎斑波状消光较弱，弱定向或无，无动态重结晶，石英c轴点极密均为位于边缘，指示了底面滑移为主，呈现脆韧性变形特征， Flinn指数K值小于1表明应变样式为压扁型椭球体。综合分析认为大巴山变形变质温度以中–低温为主，相当于绿片岩相；南、北大巴山构造变形存在显著差异性，后者变形变质温度比前者的相对较高，且变形强度呈现由北而南的递减趋势。综合研究认为，大巴山弧形构造带早期受北东向挤压形成向南西逆冲推覆，后期经历了北北东向挤压发生强烈右旋走滑。
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