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Along the North Almora Thrust (NAT) in the Kumaun Lesser Himalaya, a zone of mylonitic rocks has developed due to strain localization during the tectonic emplacement of the Almora Nappe over the Lesser Himalayan Sequence. This zone is referred here as the NAT zone (NATZ) that is dissected by faults, which are transverse to the Himalayan orographic trend and are known as seismically active structures. Trending NNW-SSE these are the Chaukhutiya and Raintoli faults. Two E-W oriented subsidiary brittle faults across the Chaukhutiya Fault are also recognized. Based on the field study and magnetic fabric analysis an attempt has been made to evaluate the deformation and kinematic history of northeastern margin of the Almora Nappe superposed by the Chaukhutiya faulting that coincides with northeastern margin of the NAT. Field study reveals brittle-ductile and brittle regimes of deformation along the Chaukhutiya Fault. Away from the NAT variable attitudes (E-W or ENE-WSW with gentle dip) of field foliation and axial planes of folds are observed, whereas at and near the NAT the attitudes of beds, including curved lithounits, are steeply dipping and are oriented parallel with the NNW-SSE trending NAT. Curvature in fold hinge line and discontinuous occurrence of lithounits are observed along the fault. Anisotropy of Magnetic Susceptibility (AMS) study of the rocks was carried out. It reveals that the anisotropy is controlled mostly by paramagnetic minerals, whereas ferromagnetic minerals have played a minor role. High temperature demagnetization through hysteresis curves has yielded negligible contribution of ferromagnetic minerals. The steep magnetic foliation is interpreted to be on account of NE-SW oriented progressive regional compression. Moreover, the magnetic foliation is inferred to represent a secondary foliation due to superimposition on primary foliation. Analyses of AMS and structural data indicate that the Chaukhutiya Fault has a strike-slip right lateral displacement including rotational component. AMS results reveal high anisotropy value (P) at the surface trace of the NAT and low anisotropy (P) away from it. Variable style of deformation is observed along the transverse fault length. [ABSTRACT FROM AUTHOR]

Assessment and inventory on soil erosion hazard are essential for the formulation of successful hazard mitigation plans and sustainable development. The objective of this study was to assess and map soil erosion hazard in Lesser Himalaya with a case study. The Dabka watershed constitutes a part of the Kosi Basin in the Lesser Himalaya, India, in district Nainital has been selected for the case illustration. The average rate of erosion hazard is 0.68 mm/year or 224 tons/km/year. Anthropogenic and geo-environmental factors have together significantly accelerated the rate of erosion. This reconnaissance study estimates the erosion rate over the period of 3 years (2006-2008) as 1.21 mm/year (398 tons/km/year) in the barren land having geological background of diamictite, siltstone and shale rocks, 0.92 mm/year (302 tons/km/year) in the agricultural land with lithology of diamictite, slates, siltstone, limestone rocks, while in the forest land, it varies between 0.20 mm/year (66 tons/km/year) under dense forest land having the geology of quartzwacke and quartrenite rocks and 0.40 mm/year (132 tons/km/year) under open forest/shrubs land having geological setup of shale, dolomite and gypsum rocks. Compared to the intensity of erosion in the least disturbed dense forest, the erosion rate is about 5-6 times higher in the most disturbed agricultural land and barren land, respectively. The erosion hazard zones delineated following scalogram modelling approach. Integrated scalogram modelling approach resulted in severe classes of soil erosion hazard in the study area with numerical values of Erosion Hazard Index (EHI) ranging between 01 (very low hazard) and 5 (very high hazard). [ABSTRACT FROM AUTHOR]