一、引言关于中强地震前其震中附近或周围地震活动的空间分布类型,已有很多人作过研究。目前讨论颇为广泛,如有地震围空,集中,条带等。本文从中短期预报的角度,着重讨论5至6级强震前几个月至几年内的弱震活动分 I. INTRODUCTION There have been many studies on the types of spatial distribution of seismic activity in the vicinity of or around the epicenter before the strong earthquake. The current discussion is quite extensive, such as earthquakes, concentration, banding and so on. This article from the perspective of short-term forecasts, focusing on the 5 to 6 before the earthquake a few months to a few years of weak earthquake activities