论文部分内容阅读
断错地貌调查和探槽开挖是获取活动断裂多期活动重要的线索.介绍了龙门山中央断裂带北川县城及平武县平通镇的断层沟槽调查及龙门山前山断裂带绵竹县汉旺镇台地前缘探槽开挖获得的认识.调查结果表明,北川断层沟槽包括汶川地震在内至少存在3次断层活动事件;平通断层沟槽包括汶川地震在内至少存在两次以上断层活动事件;汉旺探槽揭示了2～3次古地震事件.在上述3个地点中,北川断层沟槽和汉旺探槽在汶川地震前的一次强震时间接近,分别为大于5.8ka和小于6.63ka,接近为6ka.由此也获取了在汶川地震前龙门山活动断裂带的一次强震活动中,中央断裂带和前山断裂带同时活动的证据.
Fault investigation and excavation of trenches are important clues to obtain multi-period activities of active faults. A survey of fault trenches in Beichuan County and Pingtung Township of Pingwu County in central Longmenshan fault zone and the investigation of Mianzhu County The survey results show that there are at least three fault events in the Beichuan fault including the Wenchuan earthquake, and there are at least two faults in the Pingtong fault including the Wenchuan earthquake Event.The Hanwang trough revealed two or three paleoseismic events.Among the above three locations, the time of a strong earthquakes before the Wenchuan earthquake was close to the Beichuan trenches and Hanwang trenches, which were respectively greater than 5.8 ka and Less than 6.63ka and close to 6ka, so evidence of simultaneous activities of the central fault zone and the Qianshan fault zone in a strong earthquake activity of the Longmenshan active fault zone before the Wenchuan earthquake was also obtained.