华南地质与矿产2017，Vol.33Issue(4)：372-382,11.DOI:10.3969/j.issn.1007-3701.2017.04.006
长沙—湘潭一带第四纪断裂体系及形成背景探讨
Quaternary faults in Changsha-Xiangtan area and their forming tectonic settings
摘要
Abstract
There occurred a large number of Quaternary faults in Changsha-Xiangtan-Zhuzhou area. But the study of the faults is still weak.According to field investigation,contour line of Quaternary deposits thickness and former data, the authors summarized characteristics of Quaternary faults in Changsha-Xiangtan area, distin-guished stages of the faults initially,and probed into the ages and tectonic settings of the faults.The Quaternay large scale faults are mainly with NE-trending, second with NNE- or NW-trending and little with EW- to NWW-trending.The faults with different trends can be normal or reverse faults.Some are active fault that move since Late Pleistocene.There occurred Quaternary small steep faults at the artificial section in Benci Road, Ji-uhua,Xiangtan,which can be subdivided into four groups according to trends and nature such as NW-trending sinistral strike-slip faults, NE-trending dextral strike-slip faults, EW-trending sinistral strike-slip faults and NNE-trending normal faults.According to the stages of the small faults at Benci Road, and combined with the characteristics of large scale faults and regional tectonic settings,the authors put forward preliminary recognitions that the Quaternary faults in Changsha-Xiangtan area can be subdivided into four stages: the faults of the first stage are NE-, NNE-, NW- and EW-trending large scale and small normal faults, which were formed during Early Pleistocene-middle of Middle Pleistocene and in regional extensional tectonic setting;the faults of the sec-ond stage are NE-to NNE-trending thrust faults,which were formed in late of Middle Pleistocene and were con-trolled by NW-trending major pressure stress;the faults of the third stage are NW-trending sinistral strike-slip small faults and NE-trending dextral strike-slip small faults at Benci Road, which were formed during late of Middle Pleistocene-Late Pleistocene and were controlled by EW-trending major pressure stress;the faults of the fourth stage are NW-trending thrust faults and the small EW-trending sinistral strike-slip faults at Benci Road, which were formed during Late Pleistocene-Holocene and were controlled by NE-trending major pressure stress. Of the four stages faults,the first were probably related with the extension and subsidence of Dongting Basin and its adjacent areas,which can be caused by the movement of deep matter to outside under the upwelling of mantle;the faults of the later three stages can be related with the compressions of Philippine Sea plate, Qinghai-Tibet block and India-Australia plate,respectively.This study revealed the complexities of Quaternary regional tectonic deformations,tectonic regimes and dynamic mechanisms.关键词
第四纪断裂/走向/性质/期次/构造背景/长沙—湘潭地区Key words
Quaternary faults/strike/characteristics/stages/tectonic settings/Changsha-Xiangtan area分类
地质学引用本文复制引用
吴能杰,柏道远,李彬,杨少辉,钟响,曹顺红..长沙—湘潭一带第四纪断裂体系及形成背景探讨[J].华南地质与矿产,2017,33(4):372-382,11.基金项目
中国地质调查局"湖南1:5万铜官等9幅环境地质调查"项目(12120114011501)资助. （12120114011501）
