Title | Supershear rupture during the 2021 MW 7.4 Maduo, China, Earthquake |
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Author | Zhang, X ; Feng,
W ; Du, H; Samsonov, S ; Yi, L |
Source | Geophysical Research Letters vol. 49, issue 6, 2022 p. 1-11, https://doi.org/10.1029/2022GL097984 Open Access |
Image |  |
Year | 2022 |
Alt Series | Natural Resources Canada, Contribution Series 20220054 |
Publisher | AGU |
Document | serial |
Lang. | English |
Media | paper; digital; on-line |
File format | pdf |
Area | China |
Lat/Long WENS | 96.0000 101.0000 36.0000 34.0000 |
Subjects | tectonics; earthquakes; earthquake magnitudes; earthquake studies; shearing; faults, strike-slip |
Illustrations | location maps; distribution diagrams; plots; seismic velocity profiles |
Program | Canada Centre for Remote Sensing People Support and Leadership |
Released | 2022 03 28 |
Abstract | Combined with the multi-array back-projection and finite-fault joint inversion methods, we investigate the detailed spatiotemporal rupture complexity of the 2021 MW 7.4 Maduo earthquake using seismic
and geodetic data. Our results reveal that this earthquake ruptured bilaterally 170 km long fault segments with a duration of 38 s. The obtained back-projection results, specific aftershock signature of the supershear earthquake, and observations of
far-field Love Mach waves consistently validate that this earthquake is a supershear event. Furthermore, by analyzing global large strike-slip earthquakes, we find that the momentscaled radiated energies of previously well confirmed supershear
earthquakes with relatively simple fault geometries are similar to that of the 2021 MW 7.4 Maduo earthquake, which are significantly smaller than those of subshear strike-slip events. This new finding provides additional supporting evidence to
validate the supershear rupture during the 2021 MW 7.4 Maduo earthquake. |
Summary | (Plain Language Summary, not published) On 21 May 2021, an MW 7.4 earthquake ruptured the eastern part of the Bayan Har block in the Tibetan Plateau. To enhance our understanding of the
earthquake source physics, we investigate the rupture process of this earthquake with teleseismic and regional broadband seismic, strong-motion, and InSAR observations. The combined analysis of multi-array back-projection imaging and finite-fault
joint inversion reveal that the rupture of this earthquake propagated bilaterally towards both the west and the east. The estimated rupture length and duration are 170 km and 38 s, respectively. The obtained back-projection results and specific
aftershock signature of the supershear earthquake together with the observations of Love Mach waves consistently suggest that this earthquake is a supershear event. Furthermore, the analysis of the 2021 MW 7.4 Maduo earthquake and previous global
large strike-slip earthquakes shows that supershear events with relatively simple fault geometries have significantly smaller moment-scaled radiated energies than those of subshear strike-slip events. This newly interesting finding can give a fresh
perspective to provide additional supporting evidence for validating the potential supershear earthquakes in the future. |
GEOSCAN ID | 330037 |
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