No abstract

The article chronicles the landslide dam burst event from the Eastern Ghats region of India during the Titli cyclone on 12th October 2018. The event has been marked as one of the most destructive event in the region due to the abrupt increase in rainfall intensity and duration. The highly weathered profile of the Eastern Ghats metamorphosed terrain favours such fatal incidents, mostly during the monsoon and cyclone season of the Indian subcontinent. Geological and geotechnical investigation of the region followed by numerical modeling has been done to study the cause and mechanism of the incident. From the initiation of landslide to the dam formation and afterwards the bursting event, the whole event has been simulated in the Optum G2-based finite element model. The steep laterite cliff of Eastern Ghats mountains is identified as the primary concern for the stability balance in the region. Real-time monitoring of natural dams is essential to minimize the amount of risk in the region from further occurrence of such landslide-related terminal hazards.

PGE mineralisation of significant grade and extent is reported from Bangur chromite mining area, Kendujhar district, Odisha, located to the south of the well known Baula-Nuasahi ultramafic complex. The hitherto unknown PGE mineralisation is established in a ferritchromit rich breccia zone occurring within Bangur litho-mélange. The mineralized breccia zone is traced for about 550m with a mean width of 12m in NW-SE direction. Chemical analysis of drill core samples by ICP-MS indicates an average ΣPGE content of 3.2 ppm dominated by Pt and Rh. Occurrence of discrete grains of PGM in sizes up to 45 microns is confirmed by SEM-EDX and EPMA study. Delineation of this PGE bearing zone stresses the need for preservation of gangue/matrix of the breccia zone, along with ferritchromit clasts, in the ongoing selective mining of chromite in Bangur.