湘西花垣—茶洞断裂的活动期次与运动特征

Characteristics of active phase and motion of the Huayuan-Chadong fault zone in western Hunan Province

花垣一茶洞断裂带位于湖南西部，为松桃一大庸深断裂的分支，是松桃一大庸断裂北段的一部分。通过对断裂带两侧的野外基础特征、节理发育处的测量统计、擦痕与共轭节理的应力分析以及断裂带两侧的深部钻孔勘探揭露，得出花垣一茶洞断裂带的活动至少有2个期次：一期为北东向南西向的左行剪切走滑；另一期为断裂带北侧的地层下滑，下滑距离约为550-700m。

The Huayuan-Chadong fault belt, located in western Hunan Province, is a fault branch of the deep Songtao-Dayong fault and part of the northern Songtao-Dayong fault. The work analyzed the basic field characteristics of the both sides of the fault zone, and did joint measurement statistics and stress analysis of conjugate joints and scratches. Integrated with the deep drill holes along the fault zone, it is suggested that the active period of the Huayuan-Chadong fault zone has at least two stages. The first stage was NE-SW-tren- ding left-lateral shear strike-slip, and the second stage was strata slip of northern fault zone with slipping distance of about 550~ 700 m.