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中条山北麓断裂是控制运城盆地南界的主深断裂,虽然对其研究不多,历史地震较少较弱,但活动强度不容低估.通过航空影像解译、地貌测量以及探槽开挖,对运城盐池以南小李村一带的断层分布、地貌面变形以及活动性进行了研究.依据三个探槽中断层活动痕迹,得知全新世以来该段至少发生过三次较强的古地震事件,时间分别为:1~3.5,3.6~4.4和7.4~8.8 ka BP.通过14C测年确定了断层上下盘相同年代的砾石层,并用差分GPS测量了其高差以及所在位置的地形剖面,得到(24.7±0.2)ka BP以来中条山北麓断裂带的平均滑动速率为(0.75±0.05)mm a??.结合他人的资料,计算出一次大地震的垂直断距可能为2.35 m,除以平均滑动速率,得到特征地震重复间隔可能为2940~3360 a.
The northern foot of Zhongtiao Mountain is the main fault controlling the southern boundary of Yuncheng Basin, although its research is rare and the historical earthquakes are less and weaker, but the activity intensity can not be underestimated. Through aerial image interpretation, topographic survey and trench excavation , Studied the fault distribution, deformation and activity of Xiao Li Cun in the south of Yanchi, Yuncheng.According to the trace of faults in the three trenches, it is known that there have been at least three strong paleoearthquakes in this section since Holocene , Respectively, from 1 to 3.5, from 3.6 to 4.4 and from 7.4 to 8.8 ka BP, respectively. The gravel layer in the same age from top to bottom of the fault was determined by 14C dating, and its elevation and its topographic profile were measured by differential GPS, (0.75 ± 0.05) mm a ?? in the north of Zhongtiaoshan since (24.7 ± 0.2) ka BP, the vertical fault of a large earthquake may be calculated to be 2.35 m with the exception of others With average slip rate, the characteristic seismic repeat interval may be 2940 ~ 3360 a.