湘西花垣-张家界断裂带构造变形特征与ESR定年

花垣-张家界断裂带作为雪峰山隆起带北西部的一条重要断裂带，其活动历史包含了隆起带很多的演化信息。对断裂带宏观构造、微观构造、ESR定年和流体包裹体测温的综合研究表明，其经历了挤压、伸展、走滑多期复合的演化历程，北西段的活动强度相对较强，中生代以来变形以浅部的脆性为主，并伴随了多次的低温热液活动。包裹体测温显示均一温度的众数值主要集中在120～150℃，180-200℃和270-330℃3个阶段。断裂带的石英脉ESR定年表明，其中生代以来剧烈活动时间处于燕山中-晚阶段（86-131．8Ma）。根据石英脉的野外产状和流体包裹体温度特征，结合前人资料认为雪峰山隆起带中生代从挤脏向伸展的转换时间应在131．3～120Ma之间，至110Ma年左右伸展作用趋于强烈。

The Characteristics of Huayuan- Zhangjiajie Fault Belts and ESR Dating of Wuling Mountain, Western Hunan

As an important fault belt in the northwestern XueFeng uplift zone, the movement history of Huayuan-Zhangjiajie fault belt carries much information about the revolution of uplift zone. By a comprehensive research of macrostructure, microstructure, ESR (Electron Spin Resonance) dating and temperature measuring of fluid inclusion, a conclusion can be drawn that it underwent a comprehensive revolution process which includes several times of compression, extension and compression sliding. It is shown that the active intensity in the northern part was stronger than in the southern part. Since the Mesozoic era, the deformation was brittle in the shallow crust and accompanied with more than once low temperature hydrothermal activities. Temperature measuring of fluid inclusions indicates that homogeneous temperature mainly concentrated in three intervals of 120-150℃、180-200℃ and 270-330℃. The Quartz ESR (Electron Spin Resonance) dating of fault belts demonstrates that its intense movement occurred in the period of latest middle Yanshanian and late Yanshanian (86-131.8Ma). According to the field occurrence and character of the quartz veins, combining with published data, a conclusion was drawn that the transformation time from compression to extension took place between 131.3Ma and 120Ma in Mesozoic era, up to 110Ma or so, extension became intensive.