| 1 | Subaqueous early eruptive phase of the late Aptian Rajmahal volcanism,India:Evidence from volcaniclastic rocks,bentonite,black shales,and oolite显示文摘The late Aptian(118-115 Ma) continental flood basalts of the Rajmahal Volcanic Province(RVP) are part of the Kerguelen Large Igneous Province,and constitute the uppermost part of the Gondwana Supergroup on the eastern Indian shield margin.The lower one-third of the Rajmahal volcanic succession contains thin layers of plant fossil-rich inter-trappean sedimentary rocks with pyroclasts,bentonite,grey and black shale/mudstone and oolite,whereas the upper two-thirds consist of sub-aerial fine-grained aphyric basalts with no inter-trappean material.At the eastern margin and the north-central sector of the RVP,the volcanics in the lower part include rhyolites and dacites overlain by enstatite-bearing basalts and enstatite-andesites.The pyroclastic rocks are largely felsic in composition,and comprise ignimbrite as well as coarse-grained tuff with lithic clasts,and tuff breccia with bombs,lapilli and ash that indicate explosive eruption of viscous rhyolitic magma.The rhyolites/dacites(>68 wt.%) are separated from the andesites(< 60 wt.%) by a gap in silica content indicating their formation through upper crustal anatexis with only heat supplied by the basaltic magma.On the other hand,partially melted siltstone xenoliths in enstatite-bearing basalts suggest that the enstatite-andesites originated through mixing of the upper crust with basaltic magma,crystallizing orthopyroxene at a pressure-temperature of ~3 kb/1150℃.In contrast,the northwestern sector of the RVP is devoid of felsic-intermediate rocks,and the volcaniclastic rocks are predominantly mafic(basaltic) in composition.Here,the presence of fine-grained tuffs,tuff breccia containing sideromelane shards and quenched texture,welded tuff breccia,peperite,shale/mudstone and oolite substantiates a subaqueous environment.Based on these observations,we conclude that the early phase of Rajmahal volcanism occurred under predominantly subaqueous conditions.The presence of grey and black shale/mudstone in the lower one-third of the succession across the entire Rajmahal basin provides unequivocal evidence of a shallow-marine continental shelf-type environment.Alignment of the Rajmahal eruptive centers with a major N—S mid-Neoproterozoic lineament and the presence of a gravity high on the RVP suggest a tectonic control for the eruption of melts associated with the Kerguelen plume that was active in a post-Gondwana rift between India and Australia-Antarctica. | Naresh C.Ghose Nilanjan Chatterjee Brian F.Windley | 2017 | Geoscience Frontiers2017，8，4： | 2 |
| 5 | Spread of human immunodeficiency virus 1 among men who have sex with men is emerging as a genuine social concern and affecting the general populace- case reports from Eastern India显示文摘Human immunodeficiency virus(HIV) infection among men who have sex with men(MSM) has increased to a drastic proportion throughout India in the last couple of years due to a lack of productive identification and management framework. In apprehension of social disgrace these men attempt to live a normal hetero conjugal life and, in the process, act as a bridge in spreading the virus to their women partners. In this case report we have highlighted two cases which clearly distinguished the adequacy of HIV treatment among MSM when they are diagnosed during early or late phases of infection. An intensive and ample counseling to comprehend the psychology and sexual behavior of these men was found to be critically important in both the cases. Our study, which is actually the first of its kind, recorded and documented evidence of HIV infected MSM from Eastern India and renders a ray of hope among this marginally isolated group to comprehend the challenges and health risks faced by the MSM population. It also provides a format for the medical practitioners here in managing and treating related cases. | Aroni Chatterjee Agniswar Sarkar Sabbir Ansari Sattik Siddhanta Siwalik Banerjee Rathindranath Sarkar Nilanjan Chakraborty | 2016 | World Journal of Virology2016，5，4： | 0 |
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