【摘要】 本文在多年对东北地震大形势研究基础上,根据1900年以来东北地区地震目录资料,按年最大震级、地震频度和地震活动度分别建立三个时间序列f(t),利用离散小波变换对其进行分解,结果发现三个序列的小波变换细节系数均显示平均约20年周期的时序特征,并与该区地震活跃期符合得较好。依此,对该区地震活动发展趋势作了预测,认为当前地震活跃期大约在2008年结束。更多还原

【Abstract】 On the basis of analysis about great situation of NE China earthquakes for more years,three seismic time sequences with respect to annual maximal magnitude,earthquake frequency and seismicity measure have been established,respectively,according to the earthquake catalogue in the area since 1900.By means of discrete wavelet transform method the result shows that all detail coefficients of wavelet transform in respect of three time sequences have period characteristic with 20 years.It coincides with seismic active period in the area.A prediction of seismicity trend based on the result is as follows: the seismic active period at present will be over in about 2008.更多还原