收集2015年1月—2020年8月地震自动速报综合触发系统的全部产出结果,选取国内天然地震事件结果共计1863条,与正式速报目录结果进行对比研究。研究结果显示,自动速报系统所产出的地震参数较正式速报目录发震时刻平均偏差约2s,震中位置平均偏差约8km,震源深度平均偏差约9km,震级绝对平均偏差约0.25,偏差均值为自动速报结果较正式速报结果偏大约0.1。到达产出震级标准的漏报地震事件176个,其主要原因为区域台站稀疏、台站分布不均匀、大震或前震尾波干扰等,未发生误报事件。发震时刻、震中位置和震源深度偏差较大事件的分布与漏报事件类似,多发生于台站密度较低、台站分布不均匀和速度模型与实际差异较大的地区。震级偏差主要与地震事件震级大小和震中所在位置有关,对于3.0≤M＜5.0的地震事件,产出震级最为稳定,而对于M≥6.0的地震,震级结果可靠性较低; 此外,震级偏差的大小与区域分布并无明显关系,但偏差方向具有区域特征。通过对自动速报系统运行情况的统计分析,提出了关于自动速报系统改进与完善的建议,有助于提高自动速报系统的应用效果。

In this article we collect all the results published by China's auto earthquake information release system between January 2015 and August 2020. By selecting a total of 1863 natural earthquake events in China and comparing with the formal earthquake information release catalog,we find that the earthquake parameters from the China's auto earthquake information release system,have the average 2s deviation of the origin time,the average about 8km deviation of the epicenter position,the average about 9km deviation of the focal depth,the absolute 0.25 average deviation of magnitude,and the average 0.1 deviation of magnitude higher than formal earthquake information release catalog. About 176 seismic events that reached the output magnitude standard were underreported,mainly due to sparse stations in the local area,unreasonable distribution of stations,and coda interference from large earthquakes or foreshocks. The distribution of events with large deviations at the origin time,epicenter location,and focal depth is similar to underreported events,and they mostly occur in areas where the station density is low or the velocity model differs greatly from the actual one. The magnitude deviation is mainly related to the rage of magnitude and the location of the epicenter,while the magnitude of seismic events between 3 and 5,the magnitude results are the most stable and while the magnitude greater than 6,the magnitude results are less reliable. In addition,the magnitude deviation value has no obvious relationship with the regional distribution,but the deviation direction is of regional characteristics. This paper conducts a more comprehensive statistical analysis of the operation of the auto earthquake information release system,puts forward suggestions on the improvement and perfection of the system and can help deepen the understanding of the results and improves the application effect of the system.

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中国地震台网中心青年科技基金项目(QNJJ202002)资助