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The crystallines in the Kumaon Himalaya, India are studied along Goriganga, Darma and Kaliganga valleys and found to be composed of two high-grade metamorphic gneiss sheets i.e. the Higher Himalayan Crystalline (HHC) and Lesser Himalayan Crystalline (LHC) zones. These were tectonically extruded as a consequence of the southward directed propagation of crustal deformation in the Indian plate margin. The HHC and its cover rocks i.e. the Tethyan Sedimentary Zone (TSZ) are exposed through tectonic zones within the hinterland of Kumaon Himalaya. The HHC records history of at least one episode of pre-Himalayan deformation (D 1 ), three episodes of Himalayan deformation (D 2 , D 3 , D 4 ). The rocks of the HHC in Kumaon Himalaya are thoroughly transposed by D 2 deformation into NW-SE trending S m (S 1 +S 2 ). The extent of transposition and a well-developed NE-plunging L 2 lineation indicate intense strain during D 2 throughout the studied portion of the HHC. Ductile flow continued, resulting in rotation of F 1 and F 2 folds due NE-direction and NW-SE plunging F 3 folds within the HHC. The over thickened crystalline was finally, superimposed by late-to-post collisional brittle-ductile deformation (D 4 ) and exposed the rocks to rapid erosion.Apatite Fission Track (AFT) and Zircon Fission Track (ZFT) studies from the Kumaon Himalaya suggest reactivation of the Main Central/Munsiari Thrust (MCT/MT) and Vaikrita Thrust (VT), rapid exhumation and a system that has been in topographic and exhumation steady-state since at least 4 Ma.

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During the period 2011-2015, scientific investigations in the Himalaya incorporated various geological and geophysical aspects of evolution of this mountain, including sub-surface configuration, structure and metamorphism of the Lesser Himalaya and Himalayan Metamorphic Belt, geochemistry, magmatism, stratigraphy and paleontology of the Paleo-Mesozoic Tethyan sedimentary cover, the Himalayan foreland basins, exhumation, paleoseismology and GPS measurements of convergence rates. Certain remote areas of western Arunachal Pradesh in Kameng were covered for their metamorphism and exhumation. Sm-Nd isochron plot of garnet crystals from the Lesser Himalayan Jutogh Group metamorphics provided a mean regression age of 479.7±8.5 Ma as the timing of its crystallization during an Early Ordovician tectonometamorphic event. High-resolution work on metamorphism of the Lesser and Higher Himalayan belts of Sikkim incorporating P-T-t paths and geochronology of the imbricate zones of the Main Central Thrust provided better insight into their evolution.