一、前言 近年来,我国东部地区接连发生过多次大震,每次大震前后(唐山大震除外),均有一系列小震、微震及宏观现象发生,个别情况还出现中震。这些现象,常被用作分析判断未来大震的重要依据。因而,在地震学界流传有“小震闹,大震到”的谚语。但有的地震工作者常因未将这一谚语与当地地震地质的具体条件相结合,以致造成分析判断上的重大错误。 国内外有些学者,在研究地震与活动断层的关系时,发现许多大震常和较大的断层有关,企图将地震的等级与断层的长度、宽度及规模建立起一定的关系式,并认为地震往往沿较大的活动断层产生,或在地震时产生新的断裂。这种认识,有其一定的根 I. Foreword In recent years, there have been many earthquakes in succession in the eastern part of our country. Before and after the earthquake (except for the Tangshan earthquake), a series of small earthquakes, microseisms and macroscopic phenomena occurred, and in some cases moderate earthquakes occurred. These phenomena are often used as an important basis for analyzing and judging future earthquakes. Thus, in the seismological world there is a “small chicane, big earthquake to” proverb. However, some earthquake workers often fail to combine this proverb with the specific conditions of the local earthquake geology, resulting in major errors in analysis and judgment. Some scholars at home and abroad have found that many large earthquakes are often related to larger faults in the study of the relationship between earthquakes and active faults. They attempt to establish a certain relation between the magnitude of the earthquakes and the length, width and scale of faults, and consider that earthquakes Often along the larger active fault, or in the earthquake, new fracture. This understanding has its own roots