Abstract: Fault segmentation has been playing an important role in seismic safety assessment of major engineering. There are,however,many problems either in the methods of fault segmentation themselves or in the applications to the engineering practice. This paper uses results of segmentation along three faults that have been regarded internationally as the most reliable fault segmentation to analyse the segmentation methods,segmentation features,and their uncertainties. The purpose is to establish several criteria for fault segmentation that can be used in seismic safety assessment. Following criteria are proposed: (1) Sufficient and concrete evidence is necessary for fault segmentation; (2) Uncertainties associated with fault segmentation require comprehensive segmentation features. It seems that more than three methods and more than four features may reliably delineate a fault segment; (3) In order to increase reliability of fault segmentation,reliable features should be used as much as possible; (4) It is important to pay attention to persistency of fault segmentation boundaries.

Key words: Active fault, Synthetical judgement, Criteria of segmentation, Safety assessment

摘要： 活动断裂分段在重大工程地震安全性评价中具有特别重要的意义,但无论是方法本身还是实际应用都存在着有待于进一步研究和解决的问题,这些问题不解决,可能造成不良的后果。利用国际上公认的分段研究工作最深入、段落划分最可靠的3条活动断裂的分段依据,分析和评价了所使用的方法和标志以及它们的不确定性,结合中国活动断裂的特殊性和重大工程地震安全性评价对活动断裂的特殊要求,提出4个分段准则。

关键词: 活断层, 综合判断, 分段准则, 安全性评价