气候变化领域集成服务门户(CCPortal): The 2022, Ms 6.9 Menyuan earthquake: Surface rupture, Paleozoic suture re-activation, slip-rate and seismic gap along the Haiyuan fault system, NE Tibet

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DOI	10.1016/j.epsl.2023.118412
	The 2022, Ms 6.9 Menyuan earthquake: Surface rupture, Paleozoic suture re-activation, slip-rate and seismic gap along the Haiyuan fault system, NE Tibet
	Li, Kang; Tapponnier, Paul; Xu, Xiwei; Kang, Wenjun
发表日期	2023
ISSN	0012-821X
EISSN	1385-013X
卷号	622
英文摘要	The January 8, 2022, Ms 6.9 Menyuan earthquake occurred near the junction between the western Leng Long Ling (LLL) and eastern Tuolai Shan (TLS) faults, along the Haiyuan fault system, further illuminating the geometry of that system. Based on unmanned aerial vehicle (UAV) high-resolution images and field investigation, we mapped the fault geometry and surface ruptures, and measured co-seismic offsets in detail. Our results indicate that the event ruptured both a NWW-striking, - 22 km-long segment of the west LLLF and a - EW-striking, - 4 km-long eastern segment of the TLSF, with maximum left-lateral displacements of - 3.4 and 0.95 m, respectively. Both ruptures isolate a 2.8 km-wide, left-stepping, stepover/pull-apart, rather than a releasing bend as previously inferred. However, the two faults may connect continuously at depth, as suggested by both the aftershock distribution and the interferometric synthetic aperture radar (InSAR) data inversion, following the deep Paleozoic Qilian Shan suture, which is marked at the surface by discontinuous, elongated outcrops of ultramaphic rocks. Much larger, longer-term offsets of up to - 71 and 55 m along the TLS and LLL, respectively, may have accrued since the end of the last glacial maximum (LGM, -20 ka) and the beginning of the Holocene (-10 ka), respectively. This may be taken to imply average slip-rates since such times of - 5 +/- 0.5 and 3.5 +/- 0.4 mm/yr along the LLLF and TLSF, respectively, consistent with extant InSAR/GPS rates. Based on our new UAV-based field survey and recent trenching results (Shi et al., 2019), we infer that neither the LLL nor the Gulang faults ruptured during the 1927, M 8 Gulang earthquake. The co-seismic Coulomb stress increased east of the 2022 Menyuan rupture. This, and the fact that the east-central LLLF does not appear to have ruptured in the last several hundred years may enhance the risk of occurrence of a Mw 7.4 earthquake along it. This might also imply that a large (M 8?) earthquake might rupture that segment, together with the -200 km-long Tianzhu seismic gap along the Haiyuan fault farther east, during a pending cascading event.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons .org /licenses /by-nc -nd /4 .0/).
关键词	2022 Menyuan earthquake surface rupture co-seismic and cumulative offset measurements Paleozoic suture reactivation Haiyuan/Tianzhu/Leng Long Ling seismic gaps
英文关键词	EASTERN QILIAN SHAN; SEISMOGENIC STRUCTURE; NORTHEASTERN MARGIN; QINGHAI PROVINCE; KUNLUN FAULT; TECTONIC IMPLICATIONS; TIANJINGSHAN FAULT; GANSU PROVINCE; STRIKE-SLIP; CHINA
WOS研究方向	Geochemistry & Geophysics
WOS记录号	WOS:001097917500001
来源期刊	EARTH AND PLANETARY SCIENCE LETTERS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283561
作者单位	China University of Geosciences - Beijing
推荐引用方式 GB/T 7714	Li, Kang,Tapponnier, Paul,Xu, Xiwei,et al. The 2022, Ms 6.9 Menyuan earthquake: Surface rupture, Paleozoic suture re-activation, slip-rate and seismic gap along the Haiyuan fault system, NE Tibet[J],2023,622.
APA	Li, Kang,Tapponnier, Paul,Xu, Xiwei,&Kang, Wenjun.(2023).The 2022, Ms 6.9 Menyuan earthquake: Surface rupture, Paleozoic suture re-activation, slip-rate and seismic gap along the Haiyuan fault system, NE Tibet.EARTH AND PLANETARY SCIENCE LETTERS,622.
MLA	Li, Kang,et al."The 2022, Ms 6.9 Menyuan earthquake: Surface rupture, Paleozoic suture re-activation, slip-rate and seismic gap along the Haiyuan fault system, NE Tibet".EARTH AND PLANETARY SCIENCE LETTERS 622(2023).