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在甘孜-玉树断裂带东南段保存了许多地震遗迹,但对该段的地震复发规律认识并不清楚.通过对这些地点的地貌调查和探槽开挖可以对该段全新世以来的地震活动进行研究.在错阿乡T3/T2阶地边界左旋位错达到80m;仁果乡附近1.5m高的断层陡坎延伸长达3km.在这两个地点开挖的探槽中,揭示出多次古地震事件.结合历史地震记录,甘孜-玉树断裂带东南段5600年以来共发生了多达5～6次的大地震.通过对探槽内地层的14C年龄分析,对古地震事件发生的时间进行限定并讨论地震的发生时间和间隔存在的一些规律.分析结果表明,甘孜-玉树断裂东南段地震周期性不明显,复发更具丛集特点.5600年以来存在两个活跃期和一个平静期,现今正处于第二个活跃期内.各活跃期内地震复发时间并不一致,前一活跃期间隔约1000～1300年.现今活跃期中两次历史地震间隔为534年.
Many seismic relics have been preserved in the southeast segment of the Garze-Yushu fault zone, but the understanding of the law of earthquake recurrence in this segment is not clear, and the seismic activity since this Holocene can be carried out through the geomorphologic investigation and trench excavation in these places The left-lateral dislocation at the T3 / T2 terrestrial boundary in Erzhuo County reaches 80m, and the 1.5m-high fault scarp near Yinchuan Township extends up to 3km.In the excavation of these two sites, many ancient According to the historical records, a total of 5 ~ 6 earthquakes occurred up to 566 years ago in the southeastern part of the Garze-Yushu fault zone.According to the 14C age analysis of the formation in the trench, the time of the paleoearthquakes occurred The results show that the periodicity of the southeastern part of the Garze-Yushu fault is not obvious and the recurrence is more clustered. There are two active periods and one quiet period since 5600, Is in the second active period.Each active period of earthquake recurrence time is not consistent, the previous active period of about 1000 ~ 1300. The current active period of two historical earthquake interval of 534 years.