图2  包头西6.4级地震震中附近地区断裂构造和历史地震分布图

图例说明：1.隐伏断裂；2.活动断裂；3.主要活动断裂编号；4.隆起区；5.凹陷区

断裂名称：①色尔腾山山前断裂；②乌拉山北缘断裂；③乌拉山山前断裂；④鄂尔多斯北缘断裂；

          ⑤包头断裂；⑥达拉特旗断裂；⑦大青山山前断裂

Fig.2  Map of fault structure and distribution of historical earthquakes around the

       epicentral area of the M_S 6.4 west Baotou earthquake