采用西藏测震台网记录的2008年1月-2018年12月谢通门区域定位地震,系统分析该区ML 1.5以上地震频度变化及与附近强震的对应关系,发现地震台站建设密度对谢通门地震窗监控能力影响较大,故从2008-2011年和2012年7月-2018年12月2个时段予以分析。分析发现,2012年7月开始,谢通门地震窗小震活动水平在每月20次范围内随机波动,当超过20次以上(含20次)即异常高值出现或结束后1.5年内,在半径100 km以内具有发生MS 5.0以上地震的可能,在半径1 000 km以内具有发生MS 6.5以上强震的可能。
Using regionally located earthquakes in the Xietongmen region recorded by the Tibet seismic network from January 2008 to December 2018, the frequency variation of earthquakes larger than ML 1.5 in this area and its relationship with strong earthquakes in the surrounding area are systematically analyzed. It is found that station density has a great impact on the monitoring capacity in the Xietongmen seismic window. Therefore, this study divides the study period into two pieces, i.e. from January 2008 to December 2011 and from July 2012 to December 2018 for analysis. Since July 2012, the activity level of small earthquakes in the Xietongmen seismic window has fluctuated randomly within the range of 20 times per month. When there are more than 20 times (including 20 times) per month, i.e. the abnormally high value appears or ends, within 1.5 years, there is the possibility of earthquakes larger than MS 5.0 within a radius of 100 km, and strong earthquakes larger than MS 6.5 within a radius of 1 000 km.
2020,41(2): 31-36 收稿日期:2019-09-03
DOI:10.3969/j.issn.1003-3246.2020.02.004
基金项目:谢通门地震窗活动特点及精定位研究
作者简介:土登次仁(1983-),男,工程师,主要从事地震监测预报工作。E-mail:23623515@qq.com
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