2022年6月1日四川芦山6.1级地震应急产品及震源参数初步分析

北京时间2022年6月1日17时0分四川雅安市芦山县(30.37°N,102.94°E)发生6.1级地震,中国地震台网中心于震后3min发布自动速报结果、震后9min发布正式速报结果,同时联合多家单位启动地震应急产品产出工作,共产出震源参数、历史地震、地震构造、震源机制、余震精定位、推测烈度和震源破裂过程等9类应急产品。结果显示,本次地震发生在龙门山断裂带,位于青藏高原巴颜喀拉地块、岷山构造带、川滇构造带的交汇处;震源机制解表明该地震为一次逆冲型事件;余震精定位结果显示余震展布呈近NE向,与震中区域断裂走向基本一致;烈度速报推测极震区烈度达Ⅸ度,区域面积约2km²,Ⅷ度及以上区域总面积约197km²,涉及四镇一乡。

Preliminary Analysis of Emergency Production and Source Parameters of the M6.1 Earthquake on June 01,2022 in Lushan,Sichuan Province

At 17:00 on June 1, 2022,Beijing time,an earthquake of magnitude 6.1 occurred in Lushan county(30.37°N,102.94°E),Sichuan Province. The China Earthquake Early Warning Network released the first early warning results in 5.7 seconds after the earthquake,and the automatic quick report results in 3 minutes after the earthquake. The official quick report was released by China Earthquake Network Center in 9 minutes after the earthquake. The overall emergency production accompanied with other institutes includes 9 types of data such as source parameters,historical earthquakes,seismic structures,focal mechanism,aftershock location,and estimated intensity. The results show that the earthquake occurred in the Longmenshan fault zone,at the intersection of many tectonic units,such as the Bayan Har block of the Qinghai-Tibet plateau,the Sichuan-Yunnan block,the Minshan structural belt,and the Sichuan-Yunnan structural belt. The focal mechanism solution indicates that the earthquake is from a thrusting event,and the precise location of aftershocks shows that the aftershocks are distributed in a near-NE direction,which is basically consistent with the fault trend in the epicenter area. Intensity Rapid Report speculates that the intensity of the extreme earthquake area reaches IX degree with a total area of about 2km²,and the total area of VIII degree and above is about 197km²,which is from five towns involved.