Abstract: There exist some uncertainties in dating paleoearthquakes.To improve the credibility of determination of the earthquakes,comprehensive analysis of movement patterns,sedimentary environment and micro-topography has been made to investigate the paleoseismic events along the Zemuhe active fault zone.Combined trenches were excavated near Daqingliangzi,which reveal three palaeoearthquakes with ages of 160a,3100a and 5500～8900a,respectively,and a recurrence interva1of about 3000 years.Sedimentary processes related to strike-slip fault type earthquakes are discussed and a sedimentary model is put forward for strike-slip fault on condition that bulges and reverse scarps were formed at hillside area.

Key words: palaeoearthquake, combined trench, micro-topography, Zemuhe River, sedimentary model

摘要： 古地震事件定年具不确定性,为了增加地震事件定年的可信度,文中通过断层活动方式、沉积环境和地震微地貌的综合分析来研究则木河断裂带上的古地震事件。在大箐梁子附近开挖组合探槽,揭露了3次古地震事件,分别距今约160a、3100a和5500～8900a,复发间隔为3000a左右;讨论了与走滑断层型地震相关的沉积过程,揭示了走滑断层在山坡部位形成鼓包和反向陡坎情况下的沉积模式。

关键词: 古地震, 组合探槽, 地震微地貌, 则木河, 沉积模式