近四年来,所完成的美国大陆地壳和壳下岩石圈的地震学研究比以往任何时期都多,且今后数年,这种增长势头仍将继续。有几种趋势说明了这种现象:第一,由美国 COCORP结果和英国 BIRPS 的结果所引起的对地震反射研究的兴趣,带动了几项地震反射计划的发展。其中最为活跃的研究是怀俄明大学,弗吉尼亚工艺研究所,CALCRUST 和美国地质调查局的研究计划。在加拿大,岩石圈计划已在许多地点取得显著成果。第二,对地震折射 In the last four years, the seismological studies done on crusts and crusts beneath the continental crust have been completed more than ever before, and this momentum of growth will continue in the coming years. There are several trends that illustrate this phenomenon. First, the interest in seismic reflection research, as a result of the US COCORP results and the UK BIRPS, has led to the development of several seismic reflection programs. One of the most active studies is the research program at the University of Wyoming, the Virginia Institute of Technology, CALCRUST and the US Geological Survey. In Canada, the lithosphere program has achieved remarkable results in many locations. Second, refraction of earthquakes