地震预报的实验研究及实际效果早在四十年代末、五十年代初苏联地球物理研究所就开始对地震预报问题进行了研究,在地震前兆探索中有许多重要发现,为世界所公认。首先是波速比异常的发现。1962年康德拉钦柯和涅尔谢索夫在加尔姆地区发现,一些中强震前,小震的 P 波速度 Experimental studies and practical results of earthquake prediction As early as the late 1940s and early 1950s, the Soviet Institute of Geophysics began to study the earthquake prediction problem. There are many important discoveries in the exploration of earthquake precursors, which are recognized by the world. The first is the discovery of the abnormal wave velocity ratio. In 1962 Kondratchenko and Nielsansov found in the Garm region that before some moderate-strong earthquakes, the P wave velocity