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The present study emphasizes major elemental geochemical attributes-based prediction of nature, palaeoweathering intensity, provenance, tectonic setting and palaeoclimatic condition of source area of Sabarmati alluvial sediments lying in Ahmadabad locality, Gujarat, India. The sediments successions are comprised of gravel, poorly graded sand, with dominant silty and clayey sands, silt and clay with low-to-high level of plasticity. The sediments exhibit increasing concentration of MnO followed by P2O5, TiO2, K2O, MgO, Na2O, CaO, Fe2O3, Al2O3and SiO2which supports quartz dominating sand layers in comparison with silty and clayey sequences. The values of SiO2/Al2O3, Na2O/Al2O3and K2O/Al2O3and higher values of ICV indicate immature sediments with low dilution of ‘Na’ and ‘K’. Lithologically, the majority of sediments belong to shale and Fe-shale varieties. The values of ICV, CIA, CIW and PIA and various bivarient and discrimination diagrams reveal the mechanical fragmentation, abrasion and low to moderate degree of chemical palaeoweathering of fragments of felsic and intermediate igneous rocks of rift basin located at island arch and active continental margin under arid/semi-arid conditions sporadically interfered by short-term humid and semi-humid climatic conditions were responsible for formation of sediments sequences of the area.

In the present study, attempts have been made to evaluate the geotechnical characteristics of Quaternary sediments of the Nubra Valley located in high-altitude Ladakh Himalaya to demarcate the active sediment (soil) zones and their bearing on natural hazards susceptibility and mitigation measures. The experimental works have been carried out on collected sediment (soils) samples from different locations and depths to determine their grain-size-sensitive parameters and geotechnical responses. The results reveal that the majority of uniformly graded sediments (soils) of size 0.02–2.0 mm fall in wide range of values of shear strengths, cohesions (c) and angle of internal frictions, which may be due to distinct variations in their bulk and dry densities, void ratios, and liquid and plastic limits. In view of evaluated geotechnical parameters, the sediment sequences of the valley are classified in normal and active sediment zones. The sediment layers of active zone exhibit a high rate of reduction in shear strengths and cohesions in comparison with normal zone due to higher liquid and plastic limits of sediments subjected to temperature-sensitive freezing and thawing actions and may responsible for slope instabilities, differential settlements and mass flow hazards. Hence, such sediment layers require serious and careful investigations for safe settlements and mitigation measures of natural hazards.