• 首页关于本刊投稿须知期刊订阅编委会期刊合作English
引用本文:
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 2116次   下载 3137 本文二维码信息
码上扫一扫!
分享到: 微信 更多
2014年于田MS7.3地震序列的频谱特征分析及其前震识别
郑建常1) 王鹏1) 许崇涛2) 徐芳芳3)
1)山东省地震局,济南市历城区港西路2066 号250102;2)山东省五莲地震台,山东五莲262300;3)山东省荣成地震台,山东荣成264300
摘要:
利用新疆区域数字地震台网的波形资料,对2014 年2 月12 日于田MS7. 3 地震前震和余震序列的频谱特征进行了分析。基于Brune 模型,对观测记录进行仪器响应、传播路径和场地响应的校正,使用遗传算法对于田地震序列103 次ML≥3. 0 地震的震源谱进行了反演计算。结果表明:①前震序列的拐角频率相对偏低,扣除地震矩影响后,余震的拐角频率有明显增高的趋势;②距离震中最近的YUT 台资料分析显示,于田地震几次前震活动的台站观测谱相对较为独立,与主震以及彼此之间的相关系数均不高;③序列事件和主震的台站观测谱相关系数的变化反映了序列发展的动态破裂过程,相关系数较低的事件基本上偏离了主震破裂区而发生在分支断裂上;④前震的震源谱中存在异常的高频成份。
关键词:  拐角频率  地震矩  震源谱  频谱分析  前震序列
DOI:
分类号:
基金项目:中国地震局“地震科技星火计划”(XH15026)、山东省科技发展计划项目(2014GSF120007 )及中国地震局年度震情跟踪定向工作任务(2015020105)联合资助
Spectral characteristics of 2014 Yutian MS7. 3 earthquake sequence and its application in foreshock discrimination
Zheng Jianchang1) Wang Peng1) Xu Chongtao2) Xu Fangfang3)
1) Earthquake Administration of Shandong Province,Ji’nan 250102,China;2) Wulian Seismic Station,Wulian 262300,Shandong,China;3) Rongcheng Seismic Station,Rongcheng 264300,Shandong,China
Abstract:
Based on waveform records from the Xinjiang Regional Seismic Network,the paper analyses the spectral characteristics of foreshocks and aftershocks of February 12,2014 Yutian MS7. 3 earthquake sequence. We use genetic algorithm to invert source spectrum of 103 ML≥3. 0 events of the sequence. The results show that: (1) corner frequency of foreshocks is relatively lower than that of aftershocks; (2 ) using the nearest station’s ( YUT) data,we find that the observed spectrums of foreshocks are relatively independent of each other,the correlation coefficients of foreshocks and that of foreshocks to mainshock are on the low side; ( 3 ) the variation of correlation coefficients of observed spectrums implies dynamic rupture process of the earthquake sequence and most of the events with low correlation coefficients occurred on branch faults,which deviate from the main rupture area; (4) anomalously high frequencies of seismic radiation from foreshock sources are detected,which are probably due to an anomalous rigidity of the seismogenic medium. These features may be usable in foreshock discrimination.
Key words:  Corner frequency  Seismic moment  Source spectrum  Spectral analysis  Foreshock sequence