This study conducted microtremor testing along six survey lines that cross three typical earth fissures in the Datong basin to determine the dynamic response characteristics of earth fissure sites with regard to the Fourier amplitude spectrum, response spectrum, and Arias intensity. The results show the following. (1) The predominant frequency of an earth fissure site is mainly affected by the thickness and the shear wave velocity of the soil layer and is minimally effected by the presence of an earth fissure. (2) Earth fissures have a pronounced amplification effect on dynamic response. Fourier amplitude, response acceleration, and Arias intensity are high near an earth fissure and decrease with an increase in distance from the earth fissure, tending toward stability at a distance of 20 m. (3) The area that is seriously affected by this amplification is within 6–8 m of an earth fissure, and the general affected area is farther out than this, to a distance of 25 m. (4) New construction should be avoided in an area affected by the amplification, and existing buildings in general and seriously affected areas need to be reinforced to increase their seismic fortification intensity.

本研究沿着跨越大同盆地三个典型地裂缝的6条测线进行了微震测试，以确定地裂缝地点在傅里叶振幅谱、响应谱和阿里亚斯强度方面的动态响应特征。结果如下。(1) 地裂缝位点的主导频率主要受土层厚度和横波速度的影响，受地裂缝影响最小。(2) 地裂缝对动力响应有明显的放大作用。傅里叶振幅、响应加速度和阿里亚斯强度在地裂缝附近较高，随着距地裂缝距离的增加而减小，在20 m处趋于稳定。(3)受本次放大影响严重的区域在距地裂缝6~8 m范围内，一般受影响区域在此范围外，25 m以内。(4)受放大影响的地区应避免新建，一般和严重影响地区的既有建筑需要进行加固，提高抗震设防烈度。