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结合地震间隙和强度变化分析了本世纪全国及国内主要地震活动区中强以 上地震活动特征，间隙大多在５．５ａ内,一半以上在２．５ａ内,最大间隙近１８ａ.５０年代 以后全国７．５级以上和７．０级以上、青藏块体７．０级以上地震活动及近２０ａ来台湾 ７．０级以上、华北和四川６．０级以上地震活动明显减弱，２０－３０年代青藏块体北部大 震的活动影响一直持续到７０年代，５．０－６．５级地震活动自８０年代明显增强，云南 ７０年代后形成的地震活动高潮实际上从６０年代就开始增强，华北和台湾地区表现 了强震前活动增强而甘宁青地区表现了强震后活动衰减的典型过程，制约我国地震 活动的大三角应力场、东部应力场和全球应力场具有长期稳定的２０ａ周期性，后面的 应力场依次滞后于前一个应力场约１／４个周期，前两者起主导作用，青藏块体东北缘 的地震活动除受东部应力场的影响外，还与青藏块体地壳物质东流的重要作用有关， 今后几年要特别注意四川和甘宁青６．０级以上、甘肃地区５．０级以上及新疆７．０级 以上地震。
Based on the analysis of the variation of seismic interval and intensity, the characteristics of strong earthquakes above and below the national average and major domestic seismic activity areas in this century are analyzed. Most of the gaps are within 5.5a, more than half are within 2.5a and the maximum gap is nearly 18a. Earthquake above 7.0 and above, Qinghai-Tibet block above 7.0 and recent earthquakes above 7.0 in Taiwan, earthquakes above 6.0 in North China and Sichuan were significantly weakened, while in Qinghai-Tibet The influence of large earthquakes in the north of the block continued until the 1970s. Seismic activities of the magnitude 5.0-6.5 increased significantly from the 1980s. The climax of seismic activity formed after the 1970s in Yunnan actually increased from the 1960s. Taiwan shows a typical process of enhanced activity before strong earthquakes and a decay of activities after strong earthquakes in the Gansu Ningqing region. The triangular and triangular stress fields that constrain the seismic activity in China have a long-term stable 20a-periodicity in the eastern and global stress fields, The back of the stress field in turn lags behind the previous stress field about 1/4 cycle, the first two In addition to the influence of the eastern stress field, the seismic activity on the northeastern margin of the Qinghai-Tibet block is also related to the important role played by the eastward flow of crustal material in the Qinghai-Tibet Block. In the next few years, special attention should be paid to the Sichuan-Gansu-Ningqing , Gansu 5.0 above and Xinjiang 7.0 above earthquakes.