ABSTRACT In the early hours of 1 June 2025, a series of landslides occurred in the Rajpur Village of southern Assam, Northeast India, following incessant rainfall due to early onset of the Indian Summer Monsoon (ISM). The landslides occurred almost simultaneously along the partially weathered hillslopes composed primarily of matrix supported gravels, between 03:00 and 03:30 IST. These were preceded by an extreme rainfall pulse of 230 mm recorded at 02:30 IST which is part of a cumulative total of 458.8 mm over the previous three days in the area. The landsides caused grievous injuries to a few people and damaged number of dwelling units with consequent displacements. Post disaster site investigation and first-hand accounts suggest an extreme rainfall triggered shallow landslide mechanism in play when saturation in the porous rock and soil mass exceeded threshold. In this report we present a preliminary assessment of the rainfall event and physical site factors leading to the landslides on this particular date. The good correlation observed here between rainfall record and occurrence of landslides provides an important case study to work out a regional threshold for rainfall triggered landslides in the foreland fold belt region of Northeast India. This will further contribute towards developing a region-specific landslide early warning system in a scenario of changing monsoonal regime.
ABSTRACT Glacial Lake Outburst Floods (GLOFs) are emerging as a major hazard in the Himalaya due to climate-change-driven glacier retreat and rapid glacial lake expansion. In the Indian Himalaya, particularly across Jammu and Kashmir, Ladakh, Himachal Pradesh, and Uttarakhand, expanding high-altitude lakes increasingly threaten downstream communities and infrastructure. This study examines the growing GLOF risk and evaluates potential mitigation strategies under changing climatic and socio-economic conditions. A case study of Dulung Glacier reveals a reduction in glacier area from 12.35 to 10.6 km2 between 1977 and 2020, while the associated Dulung Lake expanded from 0.1 to 0.5 km2 during the same period, representing a 400% increase in lake area. These findings highlight rapid cryospheric transformation and escalating potential for GLOF events in the region. The study emphasises the need for integrated risk-reduction strategies, including continuous monitoring, early-warning systems, and climate-resilient infrastructure planning, to enhance the resilience of vulnerable Himalayan communities.
Accurate estimation of relative permeability is essential for dynamic reservoir simulation and development planning. This study presents an integrated approach that utilises Nuclear Magnetic Resonance (NMR) log data to derive relative permeability curves for different rock types in a gas-bearing reservoir. NMR-derived porosity has been corrected for gas effects, and then absolute permeability is computed using Coates method. Flow Zone Indicator (FZI) analysis is performed to classify hydraulic flow units, which aids in identifying distinct rock types. A pseudo-capillary pressure curve is reconstructed from substituted T-2 distributions using a method based on the relationship between irreducible water saturation and geometric mean T-2. These pseudo-capillary pressure curves are then used to estimate normalised saturation and to compute relative permeability curves using the Corey method. This workflow demonstrates that NMR data, when appropriately processed, can serve as a powerful tool for estimating relative permeability in the absence of extensive laboratory measurements, offering significant value for reservoir characterisation and simulation workflows.
We report here for the first time the spectroscopic investigations on St. Severin meteorite using Fourier transform infrared spectroscopy, focusing on its mineralogical phases. The St. Severin LL6 chondrite is dominated by Mg-rich olivine, with whole-rock composition of SiO2 (40.50-40.75 wt%), MgO (25.40-25.58 wt%), and FeO (18.60-18.80 wt%). Minor oxides include Al2O3, CaO, Cr2O3, TiO2 and MnO. Infrared spectroscopy shows characteristic olivine bands near 980, 885, 835, 600, and 500 cm-1, with positions reflecting the Mg/Fe ratio. Diffuse reflectance spectra in the 10 and 20 mu m regions are analogous to Fo-rich dunite and consistent with interplanetary dust and astrophysical silicate observations, confirming Mg-rich olivine dominance. Minor variations in band widths and intensities likely arise from Fe content, grain size, and crystallinity. These results demonstrate the mineralogical similarity between St. Severin, terrestrial dunites, and cosmic silicates, highlighting the extensive occurrence of Mg-rich olivine in meteoritic and astrophysical environments.
