大寺断裂构造特征研究  

Study on the Structural Features of the Dasi Fault

作　　者：张文朋[1] 高武平[1] 闫成国[1] 林逸 ZHANG Wen-peng;GAO Wu-ping;YAN Cheng-guo;LIN Yi(Tianjin Earthquake Agency,Tianjin 300210,China)

机构地区：[1]天津市地震局,天津300201

出　　处：《地震》2021年第3期90-103,共14页Earthquake

基　　金：地震科技星火计划项目(XH19003Y);天津市地震局青年基金项目(20181023)。

摘　　要：大寺断裂穿过天津市中心城区,目前尚未对其进行过系统的探测研究,其空间展布及第四纪活动性证据不足。据钻孔、重力、大地电磁等资料,大寺断裂切割深度大于10 km,在新近纪之前曾发生过较大规模的正断层活动,造成了下盘地层的大量剥蚀,并构成了断裂东侧晚古生代—中生代地层的分布边界,其在中—新生代活动较强烈,第四纪以来活动较弱。结合最近的浅层人工地震勘探成果,确定了大寺断裂的空间展布及活动时代等构造特征。大寺断裂总体走向NNE,倾向E,南起胡连庄北,经团泊东、大寺西,穿过市区东南,止于东丽区万新庄东,总长约36 km,最新活动时代为中更新世晚期;断裂在陈塘庄南发育一小分支断裂,走向NEE,倾向NW,长约5 km,最新活动时代为中更新世。The Dasi fault passes through the urban area of Tianjin,however,there is no systematic exploration or research on it.Therefore,the evidence for its spatial distribution and Quaternary activity is insufficient.According to the data of drilling,gravity,magnetotellurics etc.,the cutting depth of the Dasi fault is greater than 10 km.Before the Neogene,great normal fault activity happened along the Dasi fault,and resulted in the remarkable denudation of the footwall.In consequence,the Dasi fault has become the west boundary of the Neopaleozoic and Mesozoic strata that distributed to the east of it.The activity of the Dasi fault was relatively strong in the Meso-Cenozoic and became weaker since the Quaternary.Combined with the latest results of shallow artificial seismic exploration,this paper determined the structural characteristics,the spatial distribution and active age,etc.of the Dasi fault.The Dasi fault has a total length of about 36 km.It generally strikes NNE and dips to the E.It starts from the north of Hulianzhuang,passes through the east of Tuanbo,the west of Dasi,the southeast of the urban area,and ended at the east area of the Wanxinzhuang,Dongli District.The latest active age of the Dasi fault is the late Middle Pleistocene.A small branch fault developed south to the Chentangzhuang is about 5 km long with NEE trending and NW dipping.Its latest active age is Middle Pleistocene.

关 键 词：大寺断裂 浅层地震勘探 构造特征 

分 类 号：P315.2[天文地球—地震学]