| 摘要: |
| 2021年5月22日02时04分11.3秒（北京时间）青海果洛州玛多县发生M7.4地震。中国地震台网中心在震后立即启动余震监测和统计工作，于震后9min发布正式速报结果。同时，中国地震台网中心联合多家单位，共产出9类14种数据产品。产品结果显示，本次地震发生在巴颜喀拉块体，位于甘德南缘断裂带和玛多甘德地震带之间，推测极震区的烈度达到Ⅸ度；震源机制解显示该地震为一次走滑型事件，余震在震中两侧均有分布，总体呈NW-SE走向；震源破裂过程的结果表明本次地震持续时间约为45s，主要能量在震后30s释放，地震的破裂方式为双侧破裂，最大滑移量达4.5m，地壳浅层滑动位移量较大，推测可能存在地表破裂。 |
| 关键词: 青海玛多地震 地震速报 余震 震源机制 震源破裂 数据产品 |
| DOI： |
| 分类号:P315 |
| 基金项目:中国地震局监测预报司经常性项目“大震应急产品产出系统运维”（12150411007）资助 |
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| Fast Determination and Data Production Related to the M7.4 Earthquake on May 22,2021 in Maduo,Qinghai Province |
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Deng Wenze, Yang Zhigao, Xi Nan, Liu Jingguang, Dai Danqing, Liang Jianhong, Du Guangbao, Sun Li, Huang Zhibin
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China Earthquake Networks Center, Beijing 100045, China
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| Abstract: |
| A magnitude 7.4 earthquake hit Maduo,Qinghai Province,China at 02:04am(local time,CST)on May 22,2021. China Earthquake Networks Center reported the formal quick report in 9 minutes,and started to monitor the aftershocks immediately. Meanwhile,China Earthquake Networks Center organized some related institutions,and quickly produced 14 scientific data products of 9 categories. These products imply that this earthquake occurred in Bayan Har block,located between the Gande-Maduo faults and Gande south rim fault in terms of regional tectonics. The estimated intensity of the epicenter area reached IX degree with the focal mechanism of a strike-slip event. The aftershocks concentrate in a narrow NW-SE band with main shock located in its center. The rupture process is a bilateral mode and lasts 45s. The majority energy releases in the first 30s and the maximum slip reaches 4.5 meters in the shallow crust which may cause surface fracture. |
| Key words: Qinghai Maduo earthquake Seismic quick report Aftershocks Focal mechanism Rupture process Data products |
