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The Piedmont Zone is the least studied part of the Ganga Plain. The northern limit of the Piedmont Zone is defined by the Himalayan Frontal Thrust (HFT) along which the Himalaya is being thrust over the alluvium of the Ganga Plain. Interpretation of satellite imagery, Digital Terrain Models (DTMs) and field data has helped in the identification and mapping of various morphotectonic features in the densely forested and cultivated Piedmont Zone in the Kumaun region of the Uttarakhand state of India. The Piedmont Zone has formed as a result of coalescing alluvial fans, alluvial aprons and talus deposits. The fans have differential morphologies and aggradation processes within a common climatic zone and similar litho-tectonic setting of the catchment area. Morphotectonic analysis reveals that the fan morphologies and aggradation processes in the area are mainly controlled by the ongoing tectonic activities. Such activities along the HFT and transverse faults have controlled the accommodation space by causing differential subsidence of the basin, and aggradation processes by causing channel migration, channel incision and shifting of depocentres. The active tectonic movements have further modified the landscape of the area in the form of tilted alluvial fan, gravel ridges, terraces and uplifted gravels.

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 2 /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 2 /year) in the barren land having geological background of diamictite, siltstone and shale rocks, 0.92 mm/year (302 tons/km 2 /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 2 /year) under dense forest land having the geology of quartzwacke and quartrenite rocks and 0.40 mm/year (132 tons/km 2 /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).

Coda Q (Q c ) estimates for the Kumaun Himalaya region have been obtained in high frequency range. Local earthquakes, recorded by a digital seismic network in the region, which fall in the epicentral distances range of 10 to 80 km and with a local magnitude range of 1.4 to 2.8, have been used. The coda waves of 30 sec window length, filtered at seven frequency bands centered at 1.5, 3, 6, 9, 12, 18 and 24 Hz, have been analysed using the single backscattering model. The values of Q c estimates vary from 65 to 283 at 1.5 Hz to 2119 to 3279 at 24.0 Hz which showed that Q c is frequency dependent and its value increases as frequency increases.A frequency-dependent Q c relationship, Q c = (92 ± 4.73)f (1.07±.023) , is obtained for the region representing the average attenuation characteristics of seismic waves for Kumaun Himalaya region.

Preliminary multidisciplinary investigations were carried out in a 105 m thick late Pleistocene terrestrial sequence in the Lamayuru basin, Ladakh Himalaya. Palaeomagnetic studies reveal a reversal of polarity at about 35 ka BP. This is the only report of this reversal event in the late Pleistocene terrestrial sequences of the Indian subcontinent. The valley fill sequence is the product of an interplay of lacustrine with fluvio-deltaic to colluvial processes. Four fossiliferous horizons have yielded ostracods and gastropods indicating shallow freshwater conditions. The Lamayuru lake was created by tectonically induced instability about 35-40 ka BP, an event that may be represented widely throughout the Himalaya.