【摘要】 "区域—时间—长度算法"是一种检测地震活动水平相对变化的计算方法,利用该算法对福建及邻近海域近年来4次M_D 5.0以上地震进行回顾性检验。结果认为,每个震例的研究起始时间要根据每个地震的V_RTL背景活动水平来定,震前4个震例的均方差都超过3.5σ,3个震例的V_RTL极大值超过150,一个只有21.6。说明该地区M_D 5.0以上地震前,V_RTL活动水平相对于背景活动水平有明显变化,V_RTL可作为该地区地震预报的一项指标。更多还原

【Abstract】 Region-time-length algorithm（RTL） is a computation method for detecting relative change of earthquake activity level.Using this method,four earthquakes（M_D≥5.0） that occurred in Fujian and its offshore area for the past few years have been tested retrospective in this paper.The result shows that,research starting time of every earthquake is determined by its V_RTL background activity level,respectively.The mean square errors of the four earthquakes have all passed 3.5 a before shock.The V_RTL maximum values of three earthquakes have passed 150,and one has 21.6 only.This illustrates that V_RTL activity level have all marked variation relative to background activity level before M_D 5.0 earthquakes in this area.V_RTLmay be a index of earthquake prediction in this area.更多还原