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DOI	10.1016/j.tecto.2021.228801
	Seismotectonics and stress perspective of the Kumaon Himalaya: A geophysical evidence of a Lesser Himalayan duplex
	Hajra S.; Hazarika D.; Kumar N.; Pal S.K.; Roy P.N.S.
发表日期	2021
ISSN	00401951
卷号	806
英文摘要	The Kumaon Himalaya lies in the central seismic gap and therefore bears the potential to host a great Himalayan earthquake. The seismicity and seismotectonics of the Kumaon Himalaya and the adjacent region have been investigated based on local earthquake data recorded at 18 seismological stations. The seismically active zone of the eastern segment of the Kumaon Himalaya deviates from the usual pattern of seismicity in the Himalayan Seismic Belt of the NW Himalaya. Shallow-focus earthquakes in this region largely concentrate in the Chiplakot Crystalline Belt (CCB) immediately south of the Vaikrita Thrust. The Focal Mechanism Solutions of 41 earthquakes computed through waveform inversion technique along with the solutions of 12 earthquakes obtained from the Global Centroid Moment Tensor solution catalog are used to investigate the kinematics of the region. The study reveals a complex faulting pattern in the Inner Lesser Himalaya. The stress inversion results show a widely distributed stress pattern and low frictional coefficient which are attributed as one of the major causes of clustered seismicity observed in the CCB. Careful examination of the fault orientations indicate the presence of a hinterland dipping Lesser Himalayan Duplex over the ramp structure on the Main Himalayan Thrust. The high compressive stress and deformation rate in the CCB are partially accommodated by this duplex structure. The large concentration of shallow-focus earthquakes in the CCB is the result of the presence of fluid-rich zone as well as strain localization and large stress build-up due to locking in the ramp structure on the Main Himalayan Thrust beneath the CCB. © 2021 Elsevier B.V.
关键词	Focal mechanism solution Kumaon Himalaya Lesser Himalayan Duplex Seismotectonics
英文关键词	Chromium compounds; Compressive stress; Faulting; Friction; Centroid moment tensors; Fault orientations; Frictional coefficients; Geophysical evidence; Main himalayan thrusts; Seismically active zones; Strain localizations; Stress and deformation; Earthquakes; centroid moment tensor; duplex; earthquake event; focal mechanism; kinematics; seismic method; seismicity; seismotectonics; stress field; Himalayas; India; Kumaun Himalayas; Lesser Himalayas; Uttarakhand
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/207983
作者单位	Wadia Institute of Himalayan Geology, 33 GMS Road, Dehradun, 248 001, India; Indian Institute of Technology (ISM) Dhanbad, Jharkhand, 826004, India; Indian Institute of Technology (IIT) Kharagpur, West Bengal, 721302, India
推荐引用方式 GB/T 7714	Hajra S.,Hazarika D.,Kumar N.,et al. Seismotectonics and stress perspective of the Kumaon Himalaya: A geophysical evidence of a Lesser Himalayan duplex[J],2021,806.
APA	Hajra S.,Hazarika D.,Kumar N.,Pal S.K.,&Roy P.N.S..(2021).Seismotectonics and stress perspective of the Kumaon Himalaya: A geophysical evidence of a Lesser Himalayan duplex.Tectonophysics,806.
MLA	Hajra S.,et al."Seismotectonics and stress perspective of the Kumaon Himalaya: A geophysical evidence of a Lesser Himalayan duplex".Tectonophysics 806(2021).