分析了相邻井下、地表地震计记录的背景噪声及近震、远震波形特征,以及相关的振幅谱及近震、远震接收函数波形特征。结果表明,井下地震计记录的背景噪声比地表地震计小1个数量级,其近震、远震波形记录较清晰、简洁;井下、地表地震计记录的远震振幅谱和径向接收函数具有较好的一致性,但背景噪声、近震振幅谱、近震接收函数、远震切向接收函数波形存在一定差异;由地表地震计得到的近震震级比井下地震计的大0.12,地表地震计到井下地震计之间的P波速度约为2 km/s。
The waveforms of ambient noise, local earthquake and teleseismic earthquake, as well as related amplitude spectrum, receiver functions of local earthquake and teleseismic earthquake were analyzed in this study. The results show that the magnitude of waveforms recorded by the borehole seismometer is nearly ten percent of that recorded by the ground seismometer, and the waveforms recorded by borehole seismometer are more clear and concise than that recorded by ground seismometer. The teleseismic amplitude spectrum and radial receiver function are consistent between the borehole and ground seismometers, while the ambient noise, local earthquake amplitude spectrum, receiver function from local earthquakes and tangential receiver function from teleseismic earthquakes are different. The magnitude of local earthquake obtained by borehole seismometer is 0.12 smaller than that obtained by ground seismometer, and the P-wave velocity between the borehole seismometer and ground seismometer is ~2 km/s.
2022,43(1): 99-105 收稿日期:2019-11-22
DOI:10.3969/j.issn.1003-3246.2022.01.014
基金项目:自然资源部深地动力学重点实验室开放研究课题(项目编号:J190116)
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