太行山东缘断裂南支断层性质及断层泥K-Ar同位素定年

The character of southern branch fault in eastern marginal fault zone of Taihang Mountain and K-Ar dating of fault gouge

太行山东缘断裂是华北盆地西边界的控制性断裂,对研究华北盆地中-新生代油气藏、地震分布及成矿作用具有重要意义。通过对太行山东缘断裂南支断层几何学、运动学的详细研究以及对断层泥的X射线衍射分析、K-Ar同位素年代学研究,确定了太行山东缘断裂为枢纽性质正断层,山一系列北北东走向正断层组成,呈左阶阶梯状展布,断层活动时间为113.42±2.31 Ma。断裂在新生代再次活动,形成多幕式的断陷盆地。

Eastern marginal fault zone of Taihang Mountain is a controlling fault in western marginal of north China Basin,as it has a great meaning to oil-gas reservoir,distribution of earthquake and mineralization since Mesozoic.On basis of detailed research of geometry,kinematics,XRD of fault gouge and K-Ar isotope chronology,we confirmed that the fault zone was a normal and hinge fault,which is composed of a series of normal faults trending NNE.In the longitudinal,it presents left-lateral.The K-Ar dating of syntectonic illite showed that the fault deformed intensely during the time of 113.42±2.31 Ma.Reactivated during Cenozoic,the fault has formed a series of rift basins.