摘要
北京时间2023年12月2日22时37分在菲律宾棉兰老岛(Mindanao)东部海域发生7.6级地震。中国地震局地球物理研究所在震后启动快速响应,组织相关领域研究人员对此次地震的震源参数、震源机制、破裂过程和地震辐射能量等进行了估计,基于震源模型进行了震动图模拟、同震形变场模拟。结果表明,此次地震发生在菲律宾海板块与欧亚板块/巽他地块碰撞的俯冲带板片上,以逆冲机制为主,能量集中在前约40 s内释放,断层破裂最大滑动量达到7 m;震源辐射地震能量的效率偏低,慢度系数略低于全球平均水平,与同样矩震级大小的地震相比,震感不强烈;极震区震动烈度可能达Ⅸ度以上,可能的受灾范围近27000 km^(2);此次地震引起了显著的同震位移,最大水平向位移达到0.6 m、垂直向位移达到1.2 m。综合分析可知,此次地震不会产生大规模海啸。
At 22:37 on December 2,2023(Beijing time),a M7.6 earthquake occurred in the eastern waters of Mindanao,Philippines.The Institute of Geophysics,China Earthquake Administration initiated the response mechanism after this earthquake and organized geophysics researchers to estimate the source parameters,focal mechanism,rupture process and earthquake radiation energy of this earthquake.Based on the source model,the Shakemap and the coseismic deformation field simulation are carried out.Product results demonstrate that this earthquake occurred on the subduction zone slab where the Philippine Sea Plate collided with the Eurasian Plate/Sunda Block.This earthquake is of dominant thrusting mechanism.The energy was concentrated and released in the first 40 seconds.The maximum slip of the fault rupture is up to 7 m.The efficiency of the earthquake source in radiating seismic energy is low and the slowness coefficient is slightly lower than the average level of the global same moment magnitude earthquake,and the feeling of the earthquake is relatively weak.The earthquake intensity in the extreme seismic area possibly reaches more thanⅨ,and the approximate disaster range is up to 27000 km^(2).This earthquake caused apparent coseismic displacement with the maximum displacements reaching 0.6 m and 1.2 m in the horizontal and vertical directions respectively.Comprehensive analysis shows that this earthquake can’t produce a large-scale tsunami.
作者
王永哲
张旭
张喆
陈鲲
刘瑞丰
Wang Yongzhe;Zhang Xu;Zhang Zhe;Chen Kun;Liu Ruifeng(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)
出处
《地震科学进展》
2024年第2期168-174,共7页
Progress in Earthquake Sciences
基金
国家重点研发计划(2022YFC3003502)
中国地震局地球物理研究所基本科研业务费专项(DQJB20B18)联合资助。
