太谷断裂为太原盆地的边界断裂，是晋中盆地研究程度较低的一条断裂。根据野外地质调查，断裂展布在黄土台地前缘，断错了盆地的洪积扇及河流阶地，是一条全新世活动的正断层。在上曹麻和北甲开挖了3个探槽，根据地层基本单元和年代学测试结果，探槽揭示了3次古地震事件，分别为8ka之后、11ka之后和17ka年之后。全新世垂直滑动速率为0.09mm/a；晚更新世以来的平均滑动速率为0.16～0.19mm/a。完善了太谷断裂的研究，为晋中盆地防震减灾提供可靠的科学依据。%The Taigu fault is the boundary fault of the Taiyuan basin, and its research degree is relatively low among faults in Jin⁃zhong (central Shanxi) basin. Field geological survey shows that the fault is spread in the forefront of the loess tableland and faulted the alluvial fan and fluvial terrace of the basin, being a Holocene active fault. Three trenches were excavated in Shangcaoma and Bei⁃jia. According to the stratigraphic basic units and dating results, the trenches reveal three paleoseismic events, which took place after 8ka, after 11ka and after 17ka respectively. The vertical sliding rate of Holocene is 0.09mm/a, whereas the average sliding rate since Late Pleistocene is 0.16~0.19mm/a. The results obtained by the authors have perfected the study of the Taigu fault and provide reli⁃able scientific basis for the prevention and mitigation of earthquake disaster in Jinzhong basin.
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