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DOI	10.1016/j.tecto.2021.229013
	The 2019 September 24, Mw = 6, Mirpur earthquake, NW Himalaya: Geodetic evidence for shallow, near-horizontal décollement rupture of the Main Himalayan Thrust
	Sreejith K.M.; Jasir M.C.M.; Agrawal R.; Rajawat A.S.
发表日期	2021
ISSN	00401951
卷号	816
英文摘要	We present a source model for the 2019 Mw = 6 Mirpur earthquake, NW Himalaya using Interferometric Synthetic Aperture Radar (InSAR) measurements. Bayesian inversion of InSAR data from both ascending and descending orbits suggests that the earthquake ruptured a shallow (Depth ~ 5 km), near-horizontal (Dip ~2.5°) up-dip portion of the décollement of the Main Himalayan Thrust (MHT). The distributed slip model suggests a compact rupture terminating the up-dip end at the base of the Main Frontal Thrust (MFT) with higher slip (> 0.4 m) around the hypocentre, equivalent to a moment magnitude of Mw = 6. A shallow up-dip rupture of the MHT through a moderate magnitude earthquake is atypical as Himalayan earthquakes generally originate at the down-dip portion of the MHT and propagate towards south. We estimate a low effective coefficient of friction of 0.06 ± 0.02 from the slip model and suggest that high pore fluid pressures and/or a weak, lubricated portion of décollement could have caused a local, near-horizontal rupture at the base of the MFT. The 2019 Mirpur earthquake released a small fraction of the accumulated strain energy since the 1555 Kashmir earthquake. Coseismic Coulomb stress change analysis suggests a significant increase in stress on the locked, up-dip portion of the MHT and the frontal fold-thrust system. These findings compel a revisit of the seismic hazard assessment of the northwestern Himalaya. © 2021 Elsevier B.V.
关键词	2019 Mw = 6 Mirpur earthquake InSAR Low fault friction NW Himalaya Seismic Hazard Slip model
英文关键词	Capillary flow; Friction; Indium compounds; Strain energy; Synthetic aperture radar; Accumulated strain; Bayesian inversion; Coefficient of frictions; Coulomb stress changes; Interferometric synthetic aperture radars; Main himalayan thrusts; Pore fluid pressure; Seismic hazard assessment; Earthquakes
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/208073
作者单位	Geosciences Division, Space Applications Centre, Ahmedabad, 380015, India
推荐引用方式 GB/T 7714	Sreejith K.M.,Jasir M.C.M.,Agrawal R.,et al. The 2019 September 24, Mw = 6, Mirpur earthquake, NW Himalaya: Geodetic evidence for shallow, near-horizontal décollement rupture of the Main Himalayan Thrust[J],2021,816.
APA	Sreejith K.M.,Jasir M.C.M.,Agrawal R.,&Rajawat A.S..(2021).The 2019 September 24, Mw = 6, Mirpur earthquake, NW Himalaya: Geodetic evidence for shallow, near-horizontal décollement rupture of the Main Himalayan Thrust.Tectonophysics,816.
MLA	Sreejith K.M.,et al."The 2019 September 24, Mw = 6, Mirpur earthquake, NW Himalaya: Geodetic evidence for shallow, near-horizontal décollement rupture of the Main Himalayan Thrust".Tectonophysics 816(2021).