Main Himalayan Thrust

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Main Himalayan Thrust April 10, 2021 Main Himalayan Thrust (MHT) The Main Himalayan Thrust (MHT) is a décollement under the Himalaya Range. This thrust fault follows a NW-SE strike, reminiscent of an arc, and gently dips towards the north, beneath the region. It is the largest active continental megathrust fault in the world. The MHT accommodates crustal shortening of India and Eurasia as a result of the ongoing collision between the Indian and Eurasian plates. Deformation of the crust is also accommodated along splay structures including the Main Frontal Thrust (MFT), Main Boundary Thrust (MBT), Main Central Thrust (MCT) and possibly the South Tibetan Detachment. All these three faults (MCT, MBT, and HFF/T) conjoin along the basal detachment plane called the Main Himalayan Thrust (MHT). The MHT defines the thrust interface between the subducting Indian and the overriding Eurasian plates where there is a plane of detachment from the Indian lithosphere. On the far Tibetan side of the Himalayas, there is another fault system called the South Tibetan Detachment (STD). All these four thrusts form the base of the Tethyan Sedimentary Series of the Himalayas. In April 2015, a section of the MHT produced a blind rupture earthquake, killing nearly 9,000 Nepalese. Main Central Thrust (MCT) Zone This separates the Higher Himalayas in the north from lesser Himalayas in the south. Important role in the tectonic history of these mountains. Main Boundary Thrust (MBT) Zone It is a reverse fault of great dimensions which extends all the way from Assam to Punjab and serves. Separate the outer Himalayas from the lesser Himalayas. Himalayan Frontal Fault/Thrust (HFF/T) It is a series of reverse faults that demarcates the boundary of the Shivalik from the Himalayan province from the alluvial expanse of the Indo-Gangetic plains..

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Characterizing the Main Himalayan Thrust in the Garhwal Himalaya, India with Receiver Function CCP Stacking
Earth and Planetary Science Letters 367 (2013) 15–27 Contents lists available at SciVerse ScienceDirect Earth and Planetary Science Letters journal homepage: www.elsevier.com/locate/epsl Characterizing the Main Himalayan Thrust in the Garhwal Himalaya, India with receiver function CCP stacking Warren B. Caldwell a,n, Simon L. Klemperer a, Jesse F. Lawrence a, Shyam S. Rai b, Ashish c a Stanford University, Stanford, CA, United States b National Geophysical Research Institute, Hyderabad, India c CSIR Centre for Mathematical Modeling and Computer Simulation, NAL Belur, Bangalore, India article info abstract Article history: We use common conversion point (CCP) stacking of Ps receiver functions to image the crustal structure Received 20 November 2012 and Moho of the Garhwal Himalaya of India. Our seismic array of 21 broadband seismometers spanned Received in revised form the Himalayan thrust wedge at 79–801E, between the Main Frontal Thrust and the South Tibet 10 February 2013 Detachment, in 2005–2006. Our CCP image shows the Main Himalayan Thrust (MHT), the detachment Accepted 11 February 2013 at the base of the Himalayan thrust wedge, with a flat-ramp-flat geometry. Seismic impedance Editor: T.M. Harrison contrasts inferred from geologic cross-sections in Garhwal imply a negative impedance contrast (velocity decreasing downward) for the upper flat, located beneath the Lower Himalaya, and a positive Keywords: impedance contrast (velocity increasing downward) for the ramp, located beneath the surface trace of Himalaya the Munsiari Thrust (or MCT-I). At the lower flat, located beneath the Higher Himalaya, spatially India coincident measurements of very high electrical conductivities require the presence of free fluids, and Garhwal receiver functions we infer a negative impedance contrast on the MHT caused by ponding of these fluids beneath the CCP stacking detachment.
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Contractional Tectonics: Investigations of Ongoing Construction of The
Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2014 Contractional Tectonics: Investigations of Ongoing Construction of the Himalaya Fold-thrust Belt and the Trishear Model of Fault-propagation Folding Hongjiao Yu Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Earth Sciences Commons Recommended Citation Yu, Hongjiao, "Contractional Tectonics: Investigations of Ongoing Construction of the Himalaya Fold-thrust Belt and the Trishear Model of Fault-propagation Folding" (2014). LSU Doctoral Dissertations. 2683. https://digitalcommons.lsu.edu/gradschool_dissertations/2683 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. CONTRACTIONAL TECTONICS: INVESTIGATIONS OF ONGOING CONSTRUCTION OF THE HIMALAYAN FOLD-THRUST BELT AND THE TRISHEAR MODEL OF FAULT-PROPAGATION FOLDING A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Geology and Geophysics by Hongjiao Yu B.S., China University of Petroleum, 2006 M.S., Peking University, 2009 August 2014 ACKNOWLEDGMENTS I have had a wonderful five-year adventure in the Department of Geology and Geophysics at Louisiana State University. I owe a lot of gratitude to many people and I would not have been able to complete my PhD research without the support and help from them.
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Himalayan Megathrust Geometry and Relation to Topography Revealed by the Gorkha Earthquake J
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The 2005, Mw 7.6 Kashmir Earthquake
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Study of Fault Plane Solutions and Stress Drop Using Local Broadband Network Data: the 2011 Sikkim Himalaya Earthquake of Mw 6.9 and Its Aftershocks
ANNALS OF GEOPHYSICS, 61, 1, SE107, 2018; DOI: 10.4401/ag-7367 Study of fault plane solutions and stress drop using local broadband network data: the 2011 Sikkim Himalaya earthquake of Mw 6.9 and its aftershocks Santanu Baruah 1,2, *, Sebastiano D’Amico 3, Sowrav Saikia 4, J. L. Gautam 4, R. K. Mrinalinee Devi 1, Goutam Kashyap Boruah 1, Antara Sharma 1,2 , Mohamed F Abdelwahed 5,6 1 Geosciences & Technology Division, CSIR-North East Institute of Science & Technology (NEIST), India 2. Academy of Scientific and Innovative Research (AcSIR), CSIR-NEIST Campus, India 3. Dept. of Geosciences, University of Malta, Malta 4. National Center for Seismology, Ministry of Earth Sciences, New-Delhi, India 5. Geohazards Research Center, King Abdulaziz University, Jeddah, Saudi Arabia 6. National Research Institute of Astronomy and Geophysics, Cairo, Egypt Article history Received January 27, 2017; accepted January 22, 2018. Subject classiﬁcation: Sikkim Himalaya; Stress Drop; Seismic moment. ABSTRACT severe damages to property and also caused 60 casual - Fault plane solutions of the September 18, 2011 Sikkim Himalaya ties. This is the strongest instrumentally recorded earth - earthquake of Mw 6.9 and its four aftershocks (Mw>4.0) are studied quake in the Sikkim Himalaya during the last two by waveform inversion using the local broadband network data. The centuries [Pradhan et al. 2013]. The most signiﬁcant sig - solutions show pure strike-slip mechanisms; one aftershock show thrust natures of the 2011 Sikkim earthquake are landslides faulting with strike-slip component. Strike-slip mechanisms indicate and landslide-induced loss of life as well as damage to predominant transverse tectonics in Sikkim, in the eastern Himalaya the economy and infrastructure due to which the max - region, unlike predominant thrust tectonics in the western Himalaya.
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Kinematic Model for the Main Central Thrust in Nepal
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Modelling of Crustal Composition and Moho Depths and Their Implications Toward Seismogenesis in the Kumaon–Garhwal Himalaya Prantik Mandal*, D
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