Abstract: This paper introduced the basic principles of various seismic prospecting methods and working methods briefly according to the nationwide practices of seismic prospecting for active faults beneath big cities in recent years.Furthermore,it mainly analyzed the available range of different seismic prospecting methods,main achievements and solutions,and discussed the best combination of seismic exploration methods for detecting crustal structure and locating the faults used in the present stage,that is,to trace the faults which are at the depths of hundred meters underground using shallow seismic investigation,to detect the basement faults which are above basement(at depth of kilo～meters)using high resolution refraction sounding,and the deep crustal faults using combined seismic prospecting method of reflection seismic sounding and wide-angle reflection/refraction sounding,and furthermore,to adopt 3-D deep seismic sounding method to get 3-D velocity structure beneath city area.Thus,we can get information about fault attitude and distribution at different depths and a complete image of fault from shallow part to deep part using the combined seismic exploration method.Some application examples are presented in the article.

Key words: seismic exploration, best combination, examples of application

摘要： 根据近年来在全国开展的大城市活断层地震探测实践,在简要介绍各种地震勘探方法的基本原理和工作方法的基础上,着重分析了不同地震勘探方法的适用范围、获得的主要成果和所解决的主要问题.讨论了现阶段用地震勘探获取地壳结构和对不同深度断层定位的最佳组合方法,即对于有沉积覆盖的隐伏数百米深度至地表的断层,可用浅层地震勘探对其进行追踪,基底(埋深数公里)以上断层可采用高分辨地震折射探测;对于地壳中、深断裂应用反射地震勘探和深地震宽角反射/折射联合探测方法;还可以进一步采用三维深地震测深方法获得城市下方的三维结构和构造信息.采用这样的组合探测方法能够较好地获得断层在不同深度的产状与展布以及由深至浅完整的分布图像,并给出了应用实例.

关键词: 地震勘探, 最佳组合, 应用实例