中文摘要：

本文针对中国大陆及邻区和中国大陆地区的不同起始震级的地震资料的不同时间段、不同数据预处理的地震应变能（贝尼奥夫应变）进行小波分析,研究不同区域的地震活动周期谱及其显著性水平（即置信度）,结果表明：①在中国大陆及邻区的地震活动周期谱中,23年左右周期的置信度超过95%;45年和90年左右周期的置信度为90%左右。②中国大陆地区存在明显的25年左右周期,置信度超过95%,而其它周期并不明显。③无论是中国大陆地区还是中国大陆及邻区,同一个周期的置信度随计算资料的起始震级减小而降低。特别是中国大陆地区和大陆及邻区都存在置信度超过95%的23~25年周期对于地震的活跃与平静预测具有现实意义。而中国大陆及邻区地震活动的数十年或百年尺度的周期在地震趋势估计中是不应该被忽视的因素。

英文摘要：

Using wavelet method,we study the periodicity and its significance level（confidence） of seismic activity selected from two tpyes of regions（the China continent and adjacent regions and the China continent）,based on different starting magnitude of strain energy（Benioff strain） and during different time segment.The results show that： ① For seismic activity in the Chinese continent and adjacent regions,the confidence of 23 years′ period exceeds 95%,and those of 45 years period and 90 years period reach up to 90%;② There is an obvious period of 25 years in China continent,the confidence of which exceeds 95%;③ The confidence of the same period would decline with the decrease of starting magnitude for both types of regions.The periodicity of 23 to 25 years,the confidence of which exceeds 95% in both China continent and adjacent regions and China continent has a realistic guiding significance to the prediction of seismic activity and quiescence.The periodicity of decades and century also shouldn＇t be neglected in the analysis of earthquake tendency.