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以晋中盆地作为代表，分析了该地区的地震地质和历史地震活动的特征，联系大区域地震背景，提出１０ａ尺度的中长期地震趋势意见晋中盆地位于山西地震带一系列断陷盆地的中部，太原断裂与交城断裂为东西边界控制断裂，盆地内深断陷沿西缘的交城断裂分布，断陷深度达二三千米。全新世时期的新构造运动是地震活动的背景性条件。公元１０００年以来山西中部地区发生Ｍ≥４３４级破坏地震４３次，其中大于、等于５级的地震２５次，大于、等于６级的地震４次，破坏性地震与台网记录的小震活动均以盆地为主，盆地内又以北部太原—榆次—清徐一带占多数。地震活动的基本特征是：（１）不同震级在山西的比例是１级～２级占４０分，３级～４级占３０分，５级占１０分，６级占１０分，无７级以上地震发生。（２）中强及弱震震中区基本重合，分布在新城、徐沟、介休３个地震巢内。（３）５级以上地震几乎全部分布在盆地南部两端的太原西南和介休西北的２个强烈凹陷内。（４）地震活动具有明显的周期变化，与大区域周期吻合。以公元１０００年以来发生的６级左右地震为标志，划分出４个活跃期，这４个活跃期与大区域地震有一定的呼应关系，其韵律起伏明显受山西带地震活动的制约，最大震级一般小于山西带最大震级１?
Taking the Jinzhong Basin as a representative, this paper analyzes the characteristics of seismic geology and historical seismic activity in the area, correlates with the seismic background in a large area and proposes the ten-year long-term and mid-term seismic trend. The Jinzhong Basin is located in the central part of a series of fault basins in Shanxi Seismic Belt , Taiyuan fault and Jiaocheng fault are controlled by east-west boundary faults, and the deep fault depression in the basin distributes along Jiaocheng fault along the western margin. The depth of fault depression reaches 23 km. Neotectonic neotectonic movement is the background condition of seismic activity. M≥434 earthquakes occurred 43 times in the central part of Shanxi since the year 1000 AD, of which 25 were earthquakes larger than or equal to magnitude 5, 4 were greater than or equal to magnitude 6, and the small earthquakes recorded by destructive earthquakes and stations were both The main basin, the basin again to the north of Taiyuan - Yuci - Qing Xu area accounted for the majority. The basic characteristics of the earthquake activity are as follows: (1) The ratios of Shanxi to Shanxi with different magnitudes are 40 to 40, 3 to 4 30, 5 to 10, 6 to 10, none 7 The above earthquake occurred. (2) The strong and weak earthquakes are basically coincident in the epicenter area, and they are distributed in the three earthquake nests of Xincheng, Xugou and Jiexiu. (3) Almost all the earthquakes above M5 are distributed in the southwest of Taiyuan, southwest of the basin and two strong depressions in the northwest of Jiexiu. (4) The seismic activity has a significant periodic change, consistent with the large regional cycle. Based on the magnitude 6 earthquakes that occurred since 1000 AD, four active periods are defined. These four active periods have a certain echogenic relationship with large-scale earthquakes. Their rhythmic fluctuations are obviously constrained by the seismic activity in Shanxi Province. The maximum magnitude Generally less than the maximum magnitude of Shanxi 1?