重大工程场址断层活动的研究

A STUDY ON THE FAULT ACTIVITY IN MAJOR ENGINEERING SITE

研究重大工程场址断层活动（特别是断层的最后一次活动）对于工程的设计和建设十分必要．许多工程选址在基岩裸露区，缺乏能标明断层活动特征的新地层。为了在这些地区顺利地开展工作，笔者探索了一条新的途径，即利用变形岩石显微构造分析方法和多种测试技术对断层带物质进行综合分析测试，提取留存其中的有关断层活动规律的信息．本文论证了该方法的理论依据和可行性，并着重总结了应用该法在几个重大水电工程场址内进行断裂活动研究的成果．这些成果为工程设计人员提供了可靠的工程地质依据，也证明了该研究途径的有效性和实用性．

In ordor to study the fault activities in the major engineering site lacking recent sediments which may indicate the features of fault activities,we have developed a new research approach based on the microstructural analysis of deformation rocks and comprehensive,dating of fault materilas. In this paper, the authers discuss the theoritical basis and feasibility of the approach,and summarize the results in studying the fault activitise by means of the approach in several major engineering sites,such as Tianshengqiao Hydropower Station,the Nanpanjiang River; Dagangshan Hydropower Station,the Daduhe River; Shixiali Dam,the Sangganhe River. The results provide the reliable foundation of engineering geology for the designers and prove that the approach is valid and practical.