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秦岭造山带通常以凤县-太白走滑剪切断裂带和徽成盆地为界,分为东秦岭和西秦岭.东、西秦岭在造山后表现出多个方面的显著差异,而地处东、西秦岭分界处的凤县-太白断裂带和中生代、新生代徽成盆地为研究秦岭造山带内部中生代以来的陆内构造演化提供了有利的构造分析和沉积学研究的天然实验场所.以东、西秦岭分界处的徽成盆地和周边各主要断裂带为研究对象,通过西秦岭各个区块之间断裂带的几何学、运动学研究和徽成盆地的沉积充填过程来解释徽成盆地形成的动力学背景,揭示东、西秦岭交接部位造山后阶段的构造演化.研究结果表明:(1)秦岭造山带自晚三叠世碰撞造山以来,于早-中侏罗世发生造山之后的伸展垮塌,并形成一系列断陷盆地.(2)晚侏罗-早白垩世,在北东南西向挤压应力场下,由于秦岭造山带内部发育的大规模的左行走滑运动,使得在东、西秦岭交界部位发生陆内逃逸构造,东秦岭微板块向东有限逃逸,碧口地体侧向向西南逃逸,同时在左行剪切断裂带内沿徽成断裂南缘形成了与走滑伸展有关的呈右阶雁行排列的早白垩世沉积盆地.(3)中生代以来,徽成盆地及邻区经历了四期构造演化阶段:①早-中侏罗世的伸展断陷盆地发育阶段,②晚侏罗世强烈挤压隆升阶段,③早白垩世的走滑伸展盆地形成阶段,④晚白垩世挤压隆升阶段.
The Qinling orogenic belt is usually divided into the East Qinling and the West Qinling by the Fengxian-Taibai strike-slip shear fault zone and the Huicheng Basin, and shows significant differences in various aspects after orogenic activities in the East and West Qinling Mountains , The Fengxian-Taibai fault zone and the Mesozoic and Cenozoic Huicheng Basin at the boundary of West Qinling provide a natural experimental site for the study of tectonic evolution and sedimentology in the study of intracontinental tectonic evolution since the Mesozoic in the Qinling orogenic belt. , The major fault zones in the Huichong Basin and the surrounding areas at the boundary of West Qinling are studied. The formation of the Huicheng Basin is explained by the geometry of the fault zone, the kinematics study and the sedimentary filling process in the Huicheng Basin The results show that: (1) The extension of the Qinling orogenic belt since the Late Triassic collision orogeny occurred in the Early or Middle Jurassic after orogenic orogeny (2) Late Jurassic-Early Cretaceous, due to the large-scale left-lateral strike-slip movement developed within the Qinling orogenic belt during the compressional stress field in the northwestern and western westerlies, , The intracontinental escape structure occurred at the junction of the West Qinling Mountains, the East Qinling microplate eastward escapes in a limited manner, and the Bikou terrane fled to the southwest in the lateral direction. At the same time, along the southern margin of the Huicheng Fault in the left-lateral shear fault zone, (3) Since the Mesozoic, the Huicheng basin and its adjacent areas have undergone four stages of tectonic evolution: (1) the Early-Middle Jurassic extensional faulted basin development stage, and the Early Cretaceous sedimentary basin ② intense Jurassic uplifting stage, ③ Early Cretaceous strike-slip extensional basin forming stage, ④ Late Cretaceous uplifting stage.