• 责任者：Bai Daoyuan (Hunan Institute of Geology Survey ; Changsha 410016 ; China) ; Jia Baohua
• 刊名：Acta Geologica Sinica
• 出版年：2013
• 卷期：87(12)
• 关键词：构造变形 ; tectonic deformation ; 湖南 ; Hunan Province
• 页码：p.1791-1802
• 图表：10 tables, 38 refs.
• 分类号：0300
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

     The Xiangzhong basin is divided into Lianyuan depression and Shaoyang depression by the EW- trending Dachengshan-Longshan uplift. In the upper Paleozoic of the western Xiangzhong basin, there occur NE-to NNE-trending folds and thrust faults which have been considered to be related to the NW- thrust. This study carried out investigation over several structural sections in the western Xiangzhong basin. The results reveal the deformation characteristics. The most many axial planes of the Upper Paleozoic folds in the western Lianyuan depression are vertical with some inclined and the most axial planes of the trending thrust faults and inclined folds dip northwest with minor dipping southeast. The Dachengshan anticline is an overturned fold with an NWW-dipping axial plane and a number of NWW- dipping thrust faults are developed within core section and two wings of the anticline with the cleavages occurring in the Chang~an Formation. In the western Shaoyang depression, the thrust faults and the axial planes of inclined and overturned folds in the Upper Paleozoic dip NWW, with partial folds dipping SEE. The deformations of the cover in the Xiangzhong basin are controlled mainly by the detachment of the bottom unconformity surface and of the coal bed of the Ceshui Formation, and some faults incise through the Caledonian folded basement. Deformation characteristics of the secondary tectonic units indicate that the thrusting directions of western Xiangzhong basin are SE and not NW but not the NW direction proposed by previous studies. Studies show that the NE-to NNE-trending folds and thrust faults in the Xiangzhong basin were formed in late Middle Triassic Indosinian Movement and late Middle Jurassic Early Yanshanian Movement. Our study suggests that the SE-thrusting of the western Xiangzhong basin is related with the SE-thrusting of east periphery of the Xuefeng orogenic belt, and with the NW-subduction of Chengbu-Xinhua lithospheric fault.