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通过大探槽开挖和断层陡坎分析，揭示出发生于１６７９年８级地震的新夏垫断层自距今约２万ａ以来共发生了４次地震事件。前两次为砂体液化显示的事件；后两次为可见直接断错证据的事件。分析得到的１６７９年地震最大垂直位移为１．７５ｍ，前１６７９年事件为１．４１ｍ，是两次震级非常接近的特征地震。４次事件发生的时间分别为距今约２００００，１３０００，７５００和３１７ａ，平均重复间隔时间为（６５６１±６９１）ａ，显示了准周期重复的特征。
According to the analysis of the large trenches and the analysis of the fault scarp, it is revealed that a total of 4 earthquakes have occurred since about 20 000 a in the Xinsha pad fault occurred in the M8. 8 earthquake in 1679. The first two were the events shown by the sand liquefaction; the second two were the events that saw the direct disruption of evidence. The maximum vertical displacement of the 1679 earthquake was 1.75m and the previous event of 1679 was 1.41m, which is a characteristic earthquake with very close magnitude. The occurrences of the four events were about 20000, 13000, 7500 and 317a respectively, and the average repeat interval was (6561 ± 691) a, showing the characteristics of quasi-periodic repeats.