大青山山前断裂带晚第四纪活动速率研究

Study on the Late Quaternary Slip Rate of the Piedmont Fault of Mt. Daqingshan

一、引言活动速率是评价断裂活动强度的一个重要标志,也是确定断裂平均大震重复间隔必不可少的基本参数.因此,活动速率是活断层研究中的一个重要方面.笔者近年进行了大青山山前断裂1:5万地质填图工作,对该断裂晚第四纪活动速率作了专题研究.

The piedmont fault of Mt.Daqingshan is one of the main northern boundary faults of the Hetao basin in Inner Mongolia.It has a total length of 200km and general strikes of NEE.On the basis of geological mapping(scale:1:50000)along the fault,the authors have studied in detail the displacement and average verticaly slip rate of the fault in Late Quaternary.It has shown that the maximum average slip rate since Late Pleistocene is more than 4.0mm/a,and the maximum average Holocene slip rate is 1.72mm/a at least.Also,it is found that the fault has obvious inhomogencity in spatial and time distributions of faulting in Late Quaternary.