Quaternary activity in the northern section of the Xiaojiang fault zone
In this study,we analyze sedimentary stages in the Quaternary diluvium and its time of deposition in the Qiaojia Basin to provide sedimentological evidence of Quaternary activity in the northern section of the Xiaojiang fault zone.The results show that the Qiaojia Basin was formed in the middle of the early Pleistocene,with an average rift rate of 0.59 m/ka,and this led to the development of five diluvial sedimentary layers.Since the Quaternary,the northern section of the Xiaojiang fault zone has undergone alternating stages of quiet and active periods of tectonic activity.Five periods of tectonic activity have occurred:From the middle of the early Pleistocene to 1.6 Ma,0.81 to 0.79 Ma,0.65 to 0.59 Ma,0.48 to 0.4 Ma,and 0.12 Ma to the present.The period from 0.48 to 0.4 Ma and 0.12 Ma featured the most intense stages of tectonic activity in the northern section of the Xiaojiang fault zone.Activity in this section was closely related to the process of neotectonics,which was controlled in turn by continual lateral expansion and extrusion on the southeast edge of the Qinghai Tibet Plateau.However,this activity was weaker than that in the middle section of the fault zone.
Qiaojia Basindiluviumnorthern section of Xiaojiang fault zoneperiod of tectonic activityrift rate
万方数据
维普
