A great earthquake struck central Myanmar on March 28,2025,causing extensive and severe damage in Myanmar and neighboring countries such as Thailand.Observed waveforms indicated the possibility of supershear rupture a...A great earthquake struck central Myanmar on March 28,2025,causing extensive and severe damage in Myanmar and neighboring countries such as Thailand.Observed waveforms indicated the possibility of supershear rupture at the source of this event.To investigate this possibility,a joint source inversion using near-field and teleseismic waveforms was performed.The fault model used,with a total length of 580 km,comprises five segments with varying strike directions and dip angles.Within the first 10 s after initiation at the hypocenter,the rupture propagated southward at a high speed of 5–6 km/s.while rupture in the northern direction proceeded at a speed lower than the local S-wave velocity of 3.5 km/s.Subsequently,the rupture propagated bilaterally in both northern and southern directions at high speeds of 5–6 km/s.The largest asperity,with a maximum slip of 5–6 m,occurred in the shallow part of the fault model,approximately 240 km south of the hypocenter.Large slips of 2–3 m were also found near the southern end of the fault model.Slips on the fault plane were dominated by strike-slip components,though slips south of the largest asperity included significant dip-slip components.展开更多
基金Scientific Research Fund of Institute of Engineering Mechanics,China Earthquake Administration under Grant No.2024B15National Natural Science Fundation of China under Grant Nos.U2239252 and 52478567Natural Science Foundation of Heilongjiang Province under Grant No.JQ2023E002。
文摘A great earthquake struck central Myanmar on March 28,2025,causing extensive and severe damage in Myanmar and neighboring countries such as Thailand.Observed waveforms indicated the possibility of supershear rupture at the source of this event.To investigate this possibility,a joint source inversion using near-field and teleseismic waveforms was performed.The fault model used,with a total length of 580 km,comprises five segments with varying strike directions and dip angles.Within the first 10 s after initiation at the hypocenter,the rupture propagated southward at a high speed of 5–6 km/s.while rupture in the northern direction proceeded at a speed lower than the local S-wave velocity of 3.5 km/s.Subsequently,the rupture propagated bilaterally in both northern and southern directions at high speeds of 5–6 km/s.The largest asperity,with a maximum slip of 5–6 m,occurred in the shallow part of the fault model,approximately 240 km south of the hypocenter.Large slips of 2–3 m were also found near the southern end of the fault model.Slips on the fault plane were dominated by strike-slip components,though slips south of the largest asperity included significant dip-slip components.
