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The increasing frequency of landslides has become a matter of concern in Nagaland, a north‐eastern state of India. Noklak town, the administrative headquarter of the Noklak district in the eastern part of Nagaland bordering Myanmar, is also affected by slope stability issues. A major landslide in 1980 caused major damage to parts of the township. The problem has grown in magnitude and influence over the last four decades, damaging an area of about 1.84 km2 and several households. Slope movements have caused immense distress to the local populace by posing a constant threat to nearly one‐fourth of the town's built‐up area, roads, and cultivated tracts. Surface instability has also hampered India's Act East policy with South‐east Asian countries by disrupting the sole motorable route to the International Trade Centre at Dan (Pangsha), between India and Myanmar. A landslide susceptibility map (LSM) was generated using the Bivariate Yule coefficient (Yc) method. The LSM delineates the study area into three categories, with 23%, 23%, and 54% in high, moderate, and low susceptible zones, respectively. This was superimposed with elements such as buildings, population, roads, and cultivated tracts to assess the effects of landslides on the population and infrastructure. From the present study, it is estimated that 334 buildings, 1235 people, 2.99 km of roads, and 8 ha of cultivated landfall lie within the moderately and highly susceptible zones. Considering the rapid developmental activities that will ensue with the recent upgradation of the subdivision to that of the district, the data generated will be useful for urban sprawl and land use planning, to minimise and mitigate the loss of life and property due to landslides. [ABSTRACT FROM AUTHOR]

In this study, we analysed a rich Miocene palynological assemblage from the Upper Bhuban Formation consisting of 21 genera and 25 species of fungal remains; spores and pollen grains, along with reworked Permian palynomorphs. The latter form a relatively high abundance throughout the studied section. The abundant Hammenisporis spp. with fungal remains and geochemical data of clay minerals in the section imply that a warm and humid freshwater with oxic to anoxic continental or near‐shore depositional environment and tropical–subtropical climatic conditions prevailed during the course of sedimentation of the Upper Bhuban Formation. Geochemical studies of four selected Bhuban shale samples have been analysed for major oxide, trace elements, and rare earth elements (REE) and infer a felsic igneous rock under an active continental margin setting, with a moderate chemical to an intense chemical degree of weathering. The Rock‐Eval pyrolysis results suggest that the organic matter composition is primarily type‐III kerogen, with mixed immature and mature hydrocarbon and gas potential. [ABSTRACT FROM AUTHOR]

The Oligocene Laisong Formation in the Naga Schuppen Belt is coal bearing along the Dimapur‐Kohima Road section, Nagaland. The coals are sulphurous and classified as lignite to sub‐bituminous 'C' based on various rank parameters. The coals are dominantly composed of vitrinite followed by inertinite and liptinite in order of abundance. The coals have high‐quality Type III kerogens derived mainly from angiosperm plants. The richness and quality of organic matter in the coal is excellent to act as a petroleum source rock. Most of the maturity parameters indicate that maturity ranges from immature to early mature. The biomarker parameters and facies critical maceral associations point to deposition of the coal‐bearing strata in non‐marine/terrestrial depositional environment under moist hydrodynamic conditions, possibly in an upper delta plain environment. However, the high sulphur content of the coal points to deposition in a lower delta plain environment. Comparison with other Palaeogene coal deposits of the same sedimentary basin shows that the Laisong coals contain lesser amount of liptinite macerals and much higher amount of sulphur than these deposits. All these deposits are of similar rank, however, the Laisong coals show marginally low thermal maturity from the viewpoint of hydrocarbon generation. [ABSTRACT FROM AUTHOR]