选取大同地震台记录的2010—2019年531个MS≥5.0地震事件,根据发震区域的不同对其波形走时残差进行分析,得到不同发震区域地震波形的平均走时残差。结果表明,日本、喜马拉雅地区地震波形的走时残差总体为负值,平均残差分别为-1.51 s、-0.70 s;斐济、中国台湾地区、南美洲西海岸地区大多为正值,平均残差为0.79 s、1.83 s、1.86 s。同时发现,在有干扰的情况下参考不同区域平均走时残差计算结果,通过判断实际初至震相与理论初至震相的位置关系,可以更好地开展初至波震相识别工作。
This paper collects seismic records at Datong Seismic Station for 531 M ≥ 5.0 earthquakes from 2010 to 2019, classifies them according to their epicenter region, and obtains the average travel time residuals for different regions. The results show that:the seismic wave travel time residuals for earthquakes in Japan and the Himalayas are negative, and their average residuals are -1.51 s and -0.7 s, respectively; the travel time residuals for earthquakes in Fiji, Taiwan, and the west coast of South America are densely positive, with the average residuals of 0.79 s, 1.83 s, and 1.86 s, respectively. At the same time, it is found that in the presence of interference, referring to the calculation results of the average travel time residuals in different regions, the identification of the first arrival phases can be better carried out by judging the positional relationship of the actual first arrival phase and the theoretical first arrival phase.
2021,42(5): 30-35 收稿日期:2020-09-22
DOI:10.3969/j.issn.1003-3246.2021.05.005
基金项目:中国地震局监测、预报、科研三结合课题(项目编号:3JH-202001018)
作者简介:白伟利(1993-),男,助理工程师,主要从事地震监测和仪器运维工作。E-mail:1210837716@qq.com
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