九甸峡工程区断层测年结果研究与讨论

断层的年代测定是研究断层活动性的重要内容之一。然而, 一个工程同一条断层会出现不同的测年结果, 从而引起争议和难予决断。近年来我们通过几个大型工程区域稳定性研究, 对此获得了一些认识。本文以洮河九甸峡地区几条主干断层为研究对象, 采用同位素年龄测定与野外地质调查和显微构造分析相结合的方法, 对断层测年问题作一分析和讨论, 也许对岩土工程断层活动性研究有一定参考价值。

DISCUSSION ON DATING OF THE FAULT ACTIVITY IN JIUDIANXIA DAM AREA

Dating of fault is one of the important contents of studying the fault activity. However,different dating results are usually given for the same fault in some engineering site areas,it leads to dispute and can't make correct assessment of the fault activity.After our studying the regional stability of several large-scale engineering projects in last years,we have got some knowledge of the problem of fault activity evaluation.This paper presents some advances in study on fault dating,with an emphasis on the example of fault activity studied in Jiudianxia dam area on Taohe River,Gansu province.The main procedure of the study just is the integration of the isotopic dating,field geological investigation,and hacrostructure analysis.The research results of the faults in this paper will be valuable for the fault activity assessment and the key points to the fault dating by the methods.