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Gupta, Anupendu
- On the Occurrence of Pillow Lavas in Dalma Metavolcanic Suite, Singhbhum & Ranchi District, Bihar
Authors
1 80, Circular Road, Dinapore Cantt., Patna, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 1 (1979), Pagination: 42-44Abstract
No Abstract.- Mafic and Ultramafic Volcanism of Ongarbira Greenstone Belt, Singhbhum, Bihar
Authors
1 Geological Survey of India, Bihar Circle (E), IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 22, No 12 (1981), Pagination: 593-596Abstract
The 'Ongarbira Traps' within the Archean Iron-Ore Group metasediments in Singhbhum is characterised by the presence of mafic-ultramafic lavas, gabbro-pyroxenite with subordinate tuffaceous derivatives. The occurrence of pillow structures, intricate interlayering with sediments and association of cherts indicate subaqueous eruptive environment.- Submarine Debris-Flow Deposits from the Ordovician Mane Ting Formation in Tethyan Black Mountain Basin, Central Bhutan
Authors
1 Geological Survey of India, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 36, No 3 (1990), Pagination: 277-289Abstract
The rocks in the basin range in age from Early Ordovician to Devonian. Proximal sedimentation began with the deposition of an orthoquartzite-conglomerate lithofacies of the Nake Chu Formation. Rapid sedimentation coupled with quicker subsidence initiated a period of instability that led to the deposition of the distal facies sediments of the Mane Ting Formation characterised essentially by interbanded quartz wacke and shale with an input of andesite. A number of conformable interbedded para-conglomerate beds, identified as submarine debris flow deposits, occur within this Mane Ting Formation.
Lithic fragments ranging in size from 1 mm to 2 m and upwards constitute one modal class and are of diverse types, including quartz wacke, shale, quartzite and chert and limonitised clasts. Monocrystalline quartz, muscovite, siderite and feldspar in combination with the matrix define the second mode with size ranging from 1/4 to l/200 mm. The bimodality is interpreted to be due to mixing of the coarse sand and gravel component with the matrix.
Intact load structures and convolute folds in rip-up clasts and rafts, very poor sorting with high mud matrix, angularity of the constituent fragments. chaotic and often vertical orientation of the platy clasts and the presence of mud balls, armoured sand grains and shale-coated clasts strongly suggest transportation within a high density, cohesive debris-flow.
Keywords
Sedimentology, Debris-Flow Deposils, Ordovician, Himalaya, Bhutan.- Precambrian Colluvial Iron Ores in the Singhbhum Craton: Implications for Origin, Age of Bif-Hosted High Grade Iron Ores and Stratigraphy of the Iron Ore Group
Authors
1 Geological Survey of India, Kolkata, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 70, No 6 (2007), Pagination: 1087-1089Abstract
No Abstract.- A Note on Diamond Incidence in Wairagarh Area, Garhchiroli District, Maharashtra
Authors
1 Geological Survey of India, Seminary Hills, Nagpur - 440 006, IN