采用黑龙江地震台网记录的地震波形,基于sPn震相,计算2005—2021年黑龙江省区域内发生的11次M≥4.0近震的震源深度。分析发现,在研究区域内,可精确识别单台震中距在3° —7°范围内的地震记录波形的sPn震相。计算多台站震源深度,发现其平均值与黑龙江地震台网采用HypoSat方法测定的震源深度结果基本一致,仅3个地震的误差较大。分析认为,采用sPn震相方法测定黑龙江地区近震的震源深度准确度较高,可为日常跟踪分析工作提供依据。
The seismic waveform data of the Heilongjiang Seismic Network was used to calculate the focal depth of eleven M≥4.0 earthquakes that occurred between 2005 and 2021 based on the sPn seismic phase. The analysis found that it is easy to precisely identify sPn phases on seismograms at stations with epicentral distances between 3° and 7° in the study area. By calculating the focal depth of earthquakes using sPn phases at several stations, we found that the average value is basically consistent with that determined by the HypoSat method in Heilongjiang Seismic Network, and only three earthquakes had large errors. It shows that using the sPn phase to determine the focal depth of local earthquakes in the Heilongjiang region has high accuracy, which can provide a basis for daily tracking and analysis.
2023,44(2): 35-41 收稿日期:2022-7-7
DOI:10.3969/j.issn.1003-3246.2023.02.006
基金项目:黑龙江地震局局内科研项目(项目编号:202104)
作者简介:刘长生(1981—),男,硕士,主要从事地震分析预报工作。E-mail:lcs971215@163.com
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