【摘要】 地震区（带）的强震处于系统的前临界状态-临界状态阶段，为高强度的强震系列活动，相邻的强震时间间隔T随时间呈现逐次递减的趋势；而在后临界态阶段为低强度的地震活动系列，T随时间有递增的趋势。k为间隔序号。可以k＝AeBT关系分别描述二种不同状态的强震系列特征，对于前临界状态一临界状态B＜0，后临界状态B＞0。以中国大陆及邻区、华北地震区和青藏高原北区的拟合k－T关系，对这3个地震区的中一长期地震趋势进行了预测。更多还原

【Abstract】 Strong seismic systems are of high intensity activity under pre-critical state -critical state. Time interval between two adjacent earthquakes T has shortened with time; but the systems are lower intensity activity, and Twould be longer after the critical state. k is the exponential function of T: k = AeBT, where k is sequence number of T,A and B are coefficients, B>0 after the critical state, B<0 before the pre-critical state-critical state. k-T relations of China’s continent and adjacent area, Northern Qing-zang plateau and North China have been fitted, which have been used for middle- and long term seismic trend prediction of the above mentioned three areas.更多还原