选取2016年3月-2019年6月内蒙古地震监测台网记录的925条内蒙古东北部及邻近地区地震数据,从中挑选133次ML ≥ 2.0且记录清晰、信噪比较高的地震事件,利用Sato模型、Aki模型,分别计算该区域地震尾波平均Q值,并拟合得到Q值对频率的依赖关系,其中:①Sato模型:QC(f)=(64.11±29.15)f(0.8914±0.0772);②Aki模型:QC(f)=(258.4±65)f(0.6815±0.1435)。结果表明,利用2种模型计算的该区域地震尾波Q值分布具有一致性,且Q值与依赖指数η成反比关系,分析认为,尾波Q值高低分布与地震活动性及地质构造有关。
From 925 pieces of seismic waveform record generated by earthquakes in the northeast region of Inner Mongolia and recorded by the Inner Mongolia earthquake network from March 2016 to June 2019, 133 waveform data with ML ≥ 2.0 and a high signal-to-noise ratio are selected for analysis. Using the Sato model and the Aki model, the Q values of coda wave in northeastern Inner Mongolia are separately calculated and the relationships between the Q values and frequency are also fitted, the Sato model:QC(f)=(64.11±29.15)f(0.8914±0.0772), the Aki model:QC(f)=258.4±65)f(0.6815±0.1435). The results show that the distribution of Q values calculated using the two models in this region is consistent; the Q value is inversely proportional to the dependent index η; The analysis shows that the distribution of coda wave Q value is related to seismicity and geological structures.
2020,41(2): 44-50 收稿日期:2019-08-21
DOI:10.3969/j.issn.1003-3246.2020.02.006
基金项目:内蒙古自治区地震局局长基金(项目编号:2018JC05)
作者简介:翟浩(1990-),男,助理工程师,主要从事地震编目及系统运维工作。E-mail:496831965@qq.com
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