【摘要】 利用首都圈数字化地震台网2001—2006年的波形资料分析北京平原地区隐伏断裂的深部滑动速率。通过波形互相关分析,识别出35组相似地震对和20组多重相似对,大部分相似地震活动表现为非周期性,重复间隔从数分钟到数百天不等。针对研究区内台站分布稀疏和低信噪比波形记录的现状,在波形相似的基础上,提出了采用在子采样条件下的S-P相对到时差(dSmP)和相对到时拾取误差来对相似地震震源位置的一致性进行强约束,进一步探索和完善波形意义上重复地震的识别方法。基于4组"重复地震"估算北京平原区黄庄-高丽营断裂和南口-孙河断裂在不同孕震深度处的滑动速率为1.0～1.2mm/a,怀安镇盆地南缘断裂地表以下9.4km处的滑动速率估计值为1.5mm/a,这一结果和地质资料结果相符。更多还原

【Abstract】 Slip rates along the buried faults in Beijing plain area were investigated with the seismic waveform data between 2001 and 2006 recorded by the Beijing Digital Seismic Network.Using cross-correlation analysis of available waveforms,we identified a total of 35 doublets and 20 multiplets that show high waveform similarity.Most of these sequences are aperiodic with recurrence intervals varying from a few minutes to hundreds of days.Given the limited quantity and quality of seismic data in the study area,we have chosen a more robust approach to constrain repeated event locations.The approach incorporates both seismogram similarity by requiring cross correlation threshold and location similarity by requiring differential S-P(dSmP) time between events pairs to be small and minor internal inconsistence in travel time picking at sub-sample precision.The composite selection approach improves the identification of repeating earthquake based on similarity in waveforms.Based on four repeating sequences,we obtained the slip rate about 1.0 ～ 1.2mm/a at seismogenic depths of Hangzhuang-Gaoliying Fault and Nankou-Sunhe Fault,and the slip rate of 1.5mm/a at 9.4km of the south boundary fault of Huai’ an Basin,which is consistent with geological and geodetic measurements.更多还原