从地震学与地震地质学交叉、融合的思路出发，通过地震活动图象分析及震源机制的研究，得到了１９８９年与１９９１ 年大同—阳高两次地震震源断层的三维特征，即走向ＮＥ２５°，倾向ＮＷ，长约２０ｋｍ ，埋深５ ｋｍ ～７ ｋｍ ，宽１２ ｋｍ ，高角度，呈右旋走滑特性。指出地壳分层结构及等震线等资料与之有较好的一致性，讨论了震源断层与附近地质构造的关系。 Starting from the idea of ​​the intersection of seismology and seismology and geology and the fusion of seismic seismology and focal mechanism, the three-dimensional features of the hypocenter of Datong-Yanggao earthquake in 1989 and 1991 are obtained, ie, NE25 ° , With a tendency of NW of 20km, depth of 5 km ~ 7 km, width of 12 km, high angle, showing right-handed strike slip characteristics. It is pointed out that there is a good agreement between the crustal structure and isoseismic data, and the relationship between the focal fault and the nearby geological structure is discussed.