Bhaskar Acharya - Academia.edu (original) (raw)

Papers by Bhaskar Acharya

Research paper thumbnail of Mineral chemistry of manganese ores associated with Precambrian Eastern Ghats Complex of Andhra Pradesh-Orissa, India

JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY, 1998

Research paper thumbnail of Sulphide mineralisation in parts of Eastern Ghats complex, Orissa

Research paper thumbnail of Graphite mineralisation in Eastern Ghat migmatites around Nishikhal, south Orissa

Research paper thumbnail of Pyrophanite from Nishikhal manganese deposit, Orissa

Research paper thumbnail of Nishikhal manganese deposit, Koraput district, Orissa

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rock... more Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks. Presence of phosphorus, iron and silica beyond desirable limit in most of the ores makes them unsuitable for industrial purposes. The dominant ore minerals are psilornelane, cryptomelane, pyrolusite and goethite. These ores are formed by supergene enrichment of primary syngenetic metamorphosed assemblages. Phosphorus is present as a discrete mineral phase in the form of apatite contained in the silicate minerals, as well as fixed in the crystal structure of goethite, cryptomelane and psilomelane. Physical beneficiation may be employed to remove the silicate minerals which will ultimately reduce a part of phosphorus. Removal of iron by this method may be difficult because of the fine grain-size and complex intergrowth with goethite.

Research paper thumbnail of Cobalt-rich lithiophorite from the Precambrian Eastern Ghats manganese ore deposit of Nishikhal, south Orissa, India

Mineralogia, 2010

Fine-grained aggregates of lithiophorite are associated with cryptomelane, romanèchite, birnessit... more Fine-grained aggregates of lithiophorite are associated with cryptomelane, romanèchite, birnessite and graphite in the Precambrian Eastern Ghats manganese ore deposit of Nishikhal, south Orissa, India. High-cobalt lithiophorite is reported for the first time from the manganese ores. The mode of occurrence and the chemical composition of the lithiophorite are discussed. Along with manganese and aluminium, the lithiophorite contains appreciable quantities of CoO (1.59-8.56%) together with trace amounts of Cu, Ni, Zn, Ti, Ca, Mg, Na, K and P. The Nishikhal lithiophorite is a transition metal-rich lithiophorite.

Research paper thumbnail of Processing of low grade graphite ores of orissa, India

Minerals Engineering, 1996

... PROCESSING OF LOW GRADE GRAPHITE ORES OF ORISSA, INDIA BC ACHARYA, DS RAO, S. PRAKASH, PSR RE... more ... PROCESSING OF LOW GRADE GRAPHITE ORES OF ORISSA, INDIA BC ACHARYA, DS RAO, S. PRAKASH, PSR REDDY and SKBISWAL Regional Research ... Reddy, PSR, Kumar, SG, Bhattacharya, KK, Sastri, SRS Narasimhan, KS, Flotation column for fine coal Beneficiation ...

Research paper thumbnail of Phosphorus in the siliceous manganese ores of Nishikhal, Orissa

Research paper thumbnail of Mineralogy and genesis of Kutinga manganese deposit, South Orissa, India

JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY, 1994

Manganese ores at Kutinga occur as distinctly conformable bands in the khondalite suit of rocks o... more Manganese ores at Kutinga occur as distinctly conformable bands in the khondalite suit of rocks of Eastern Ghats complex. The dominant manganese ore minerals include cryptomelane, psilomelane, pyrolusite, hausmannite, lithiophorite and wad. Quartz, chalcedony, orthoclase, garnet and kaolinite are the associated gangue minerals. Presence of high iron, high phosphorous, low to medium silica and dominance of CaO over MgO, K2O over Na2O, Ni over Co, Zn over Pb and Cu over Pb are the characteristics of this manganese deposit. Phosphorous occurs as discrete apatite inclusions within the quartz and orthoclase; and also adsorbed in the secondary manga nese and iron minerals. Field characters, mineralogy and geochemistry of manganese ores suggest their formation as chemical precipitates, and the source of which appears to be continental erosion. Manganese formation along with the country rocks have been metamorphosed under granulite facies conditions, affected by granitisation and subsequently undergone supergene enrichment to give rise to the present deposit. These ores will be amenable to removal of silica, but will not respond well to removal of iron and phosphorous by physical beneficiation.

Research paper thumbnail of Seasonal variations of phytoplankton in Mahanadi estuary, east coast of India

Seasonal variations of phytoplankton and chlorophyll-a along with its environmental variations in... more Seasonal variations of phytoplankton and chlorophyll-a along with its environmental variations including nutrients were studied from June-2004 to March-2007. Samples were collected in three different seasons pre-monsoon (May-June), post-monsoon (October-November) and summer (February-March) from the Mahanadi estuary. Seventy seven species of phytoplankton were encountered during the study period of which, diatoms (Bacillariophyceae) was the dominant group followed by dinoflagellates (Dinophyceae)

Research paper thumbnail of Heavy Mineral Placer Sand Deposits of Kontiagarh Area, Ganjam District, Orissa, India

Resource Geology, 2009

Skip to Main Content. ...

Research paper thumbnail of Mineralogy, chemistry and genesis of Nishikhal manganese ores of South Orissa, India

Mineralium Deposita, 1997

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rock... more Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks belonging to the Precambrian Eastern Ghats complex of south Orissa, India. Manganese minerals recorded are cryptomelane, romanechite, pyrolusite, with minor amounts of jacobsite, hausmannite, braunite, lithiophorite, birnessite and pyrophanite. Goethite, graphite, hematite and magnetite are the other opaque minerals and quartz, orthoclase, garnet, kaolinite, apatite, collophane, fibrolite, zircon, biotite and muscovite are the gangue minerals associated with these ores. The mineral chemistry of some of the phases, as well as the modes of association of phosphorous in these ores have been established. The occurrence of well-defined bands of manganese ore; co-folding of manganese ore bands and associated metasedimentary country rocks; the mineral assemblage of spessartite-sillimanite-braunite-jacobsite-hausmannite; the geochemical association of Mn-Ba-Co-Ni-Zn together with the Si versus Al and Na versus Mg plots of the manganese ores suggest that the Nishikhal deposit is a metamorphosed Precambrian lacustrine deposit. Continental weathering appears to be the source for manganese and iron. After deposition and probable diagenesis, the manganese-rich sediments were metamorphosed along with conformable psammitic and pelitic sediments under granulite facies conditions, and subsequently underwent supergene enrichment to produce the present deposit.

Research paper thumbnail of Hydrology and assessment of lotic water quality in Cuttack city, India

Water, Air, & Soil Pollution, 2003

A total of 120 water and sewage samples were collected from 20 stations over six consecutive seas... more A total of 120 water and sewage samples were collected from 20 stations over six consecutive seasons in two years in order to study the possible impact of domestic sewage on the lotic water in and around Cuttack, India. A majority of samples exceeded the maximum permissible limit set by WHO for NH + 4 and NO − 3 contents. Total viable count (TVC) and Escherichia coli (E. coli) counts in all the samples were high and the waters were not potable. The nutrient characteristics of the study area exhibited drastic temporal variation indicating highest concentration during the summer season compared to winter and rains. The persistence of dissolved oxygen (DO) deficit and very high biochemical oxygen demands (BOD) all along the water courses suggest that the deoxygenation rate of lotic water was much higher than reoxygenation. Hierarchical cluster analysis of the various physico-chemical and microbial parameters established three different zones and the most contaminated zone was found to be near the domestic sewage mixing points.

Research paper thumbnail of Anthropogenic Impact on Water Quality of Chilika Lagoon RAMSAR Site: a Statistical Approach

Wetlands Ecology and …, 2007

This paper investigated the spatiotemporal variability of water quality parameters (transparency,... more This paper investigated the spatiotemporal variability of water quality parameters (transparency, salinity, dissolved oxygen, nutrients viz. NH 3-N, NO 2-N, NO 3-N, PO 4 3-P, total nitrogen, total phosphorous and chlorophyll-a) in Chilika lagoon during 2001-2003 in order to better understand its ecological characteristics. Marked spatial and seasonal variations were detected with respect to almost all parameters studied. Northern sector of the lagoon is more affected by the anthropogenic stress from the catchments than the southern sector. Addition of nitrogen and phosphorous compounds to the lagoon mainly occurred through the drainage from agricultural lands and river run off during the early months of paddy cultivating seasons. Phytoplankton productivity of the lagoon was nitrogen limited, as suggested by nitrogen to phosphorous ratio. Processes affecting the water quality of the lagoon system included agricultural drainage, sewage intrusion, macrophyte litter fall and exchange of water between lagoon and the sea (Bay of Bengal). Further in depth study pertaining to quantification of exogenous material input and their disposal is recommended to ensure proper management of the lagoon and its resources.

Research paper thumbnail of Remote Monitoring of Sediment Dynamics in a Coastal Lagoon: Long-term Spatio-temporal Variability of Suspended Sediment in Chilika

Estuarine, Coastal and Shelf Science, 2016

Research paper thumbnail of Variability of nutrients and phytoplankton biomass in a shallow brackish water ecosystem (Chilika Lagoon, India)

Limnology, 2009

... KK Satapathy Environmental and Industrial Safety Section, IGACR (DAE), Kalpakkam 603102, Tami... more ... KK Satapathy Environmental and Industrial Safety Section, IGACR (DAE), Kalpakkam 603102, Tamilnadu, India BC Acharya Institute of Minerals and Materials Technology, Bhubaneswar 751013, India 123 ... TN (µg l-1) 200 300 400 500 600 700 800 900 g TP (µg l-1) ...

Research paper thumbnail of Phosphorus in the siliceous manganese ores of Nishikhal, Orissa

Research paper thumbnail of Sulphide mineralisation in parts of Eastern Ghats complex, Orissa

Research paper thumbnail of Mineral chemistry of manganese ores associated with Precambrian Eastern Ghats Complex of Andhra Pradesh-Orissa, India

Research paper thumbnail of Graphite mineralisation in Eastern Ghat migmatites around Nishikhal, south Orissa

Research paper thumbnail of Mineral chemistry of manganese ores associated with Precambrian Eastern Ghats Complex of Andhra Pradesh-Orissa, India

JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY, 1998

Research paper thumbnail of Sulphide mineralisation in parts of Eastern Ghats complex, Orissa

Research paper thumbnail of Graphite mineralisation in Eastern Ghat migmatites around Nishikhal, south Orissa

Research paper thumbnail of Pyrophanite from Nishikhal manganese deposit, Orissa

Research paper thumbnail of Nishikhal manganese deposit, Koraput district, Orissa

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rock... more Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks. Presence of phosphorus, iron and silica beyond desirable limit in most of the ores makes them unsuitable for industrial purposes. The dominant ore minerals are psilornelane, cryptomelane, pyrolusite and goethite. These ores are formed by supergene enrichment of primary syngenetic metamorphosed assemblages. Phosphorus is present as a discrete mineral phase in the form of apatite contained in the silicate minerals, as well as fixed in the crystal structure of goethite, cryptomelane and psilomelane. Physical beneficiation may be employed to remove the silicate minerals which will ultimately reduce a part of phosphorus. Removal of iron by this method may be difficult because of the fine grain-size and complex intergrowth with goethite.

Research paper thumbnail of Cobalt-rich lithiophorite from the Precambrian Eastern Ghats manganese ore deposit of Nishikhal, south Orissa, India

Mineralogia, 2010

Fine-grained aggregates of lithiophorite are associated with cryptomelane, romanèchite, birnessit... more Fine-grained aggregates of lithiophorite are associated with cryptomelane, romanèchite, birnessite and graphite in the Precambrian Eastern Ghats manganese ore deposit of Nishikhal, south Orissa, India. High-cobalt lithiophorite is reported for the first time from the manganese ores. The mode of occurrence and the chemical composition of the lithiophorite are discussed. Along with manganese and aluminium, the lithiophorite contains appreciable quantities of CoO (1.59-8.56%) together with trace amounts of Cu, Ni, Zn, Ti, Ca, Mg, Na, K and P. The Nishikhal lithiophorite is a transition metal-rich lithiophorite.

Research paper thumbnail of Processing of low grade graphite ores of orissa, India

Minerals Engineering, 1996

... PROCESSING OF LOW GRADE GRAPHITE ORES OF ORISSA, INDIA BC ACHARYA, DS RAO, S. PRAKASH, PSR RE... more ... PROCESSING OF LOW GRADE GRAPHITE ORES OF ORISSA, INDIA BC ACHARYA, DS RAO, S. PRAKASH, PSR REDDY and SKBISWAL Regional Research ... Reddy, PSR, Kumar, SG, Bhattacharya, KK, Sastri, SRS Narasimhan, KS, Flotation column for fine coal Beneficiation ...

Research paper thumbnail of Phosphorus in the siliceous manganese ores of Nishikhal, Orissa

Research paper thumbnail of Mineralogy and genesis of Kutinga manganese deposit, South Orissa, India

JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY, 1994

Manganese ores at Kutinga occur as distinctly conformable bands in the khondalite suit of rocks o... more Manganese ores at Kutinga occur as distinctly conformable bands in the khondalite suit of rocks of Eastern Ghats complex. The dominant manganese ore minerals include cryptomelane, psilomelane, pyrolusite, hausmannite, lithiophorite and wad. Quartz, chalcedony, orthoclase, garnet and kaolinite are the associated gangue minerals. Presence of high iron, high phosphorous, low to medium silica and dominance of CaO over MgO, K2O over Na2O, Ni over Co, Zn over Pb and Cu over Pb are the characteristics of this manganese deposit. Phosphorous occurs as discrete apatite inclusions within the quartz and orthoclase; and also adsorbed in the secondary manga nese and iron minerals. Field characters, mineralogy and geochemistry of manganese ores suggest their formation as chemical precipitates, and the source of which appears to be continental erosion. Manganese formation along with the country rocks have been metamorphosed under granulite facies conditions, affected by granitisation and subsequently undergone supergene enrichment to give rise to the present deposit. These ores will be amenable to removal of silica, but will not respond well to removal of iron and phosphorous by physical beneficiation.

Research paper thumbnail of Seasonal variations of phytoplankton in Mahanadi estuary, east coast of India

Seasonal variations of phytoplankton and chlorophyll-a along with its environmental variations in... more Seasonal variations of phytoplankton and chlorophyll-a along with its environmental variations including nutrients were studied from June-2004 to March-2007. Samples were collected in three different seasons pre-monsoon (May-June), post-monsoon (October-November) and summer (February-March) from the Mahanadi estuary. Seventy seven species of phytoplankton were encountered during the study period of which, diatoms (Bacillariophyceae) was the dominant group followed by dinoflagellates (Dinophyceae)

Research paper thumbnail of Heavy Mineral Placer Sand Deposits of Kontiagarh Area, Ganjam District, Orissa, India

Resource Geology, 2009

Skip to Main Content. ...

Research paper thumbnail of Mineralogy, chemistry and genesis of Nishikhal manganese ores of South Orissa, India

Mineralium Deposita, 1997

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rock... more Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks belonging to the Precambrian Eastern Ghats complex of south Orissa, India. Manganese minerals recorded are cryptomelane, romanechite, pyrolusite, with minor amounts of jacobsite, hausmannite, braunite, lithiophorite, birnessite and pyrophanite. Goethite, graphite, hematite and magnetite are the other opaque minerals and quartz, orthoclase, garnet, kaolinite, apatite, collophane, fibrolite, zircon, biotite and muscovite are the gangue minerals associated with these ores. The mineral chemistry of some of the phases, as well as the modes of association of phosphorous in these ores have been established. The occurrence of well-defined bands of manganese ore; co-folding of manganese ore bands and associated metasedimentary country rocks; the mineral assemblage of spessartite-sillimanite-braunite-jacobsite-hausmannite; the geochemical association of Mn-Ba-Co-Ni-Zn together with the Si versus Al and Na versus Mg plots of the manganese ores suggest that the Nishikhal deposit is a metamorphosed Precambrian lacustrine deposit. Continental weathering appears to be the source for manganese and iron. After deposition and probable diagenesis, the manganese-rich sediments were metamorphosed along with conformable psammitic and pelitic sediments under granulite facies conditions, and subsequently underwent supergene enrichment to produce the present deposit.

Research paper thumbnail of Hydrology and assessment of lotic water quality in Cuttack city, India

Water, Air, & Soil Pollution, 2003

A total of 120 water and sewage samples were collected from 20 stations over six consecutive seas... more A total of 120 water and sewage samples were collected from 20 stations over six consecutive seasons in two years in order to study the possible impact of domestic sewage on the lotic water in and around Cuttack, India. A majority of samples exceeded the maximum permissible limit set by WHO for NH + 4 and NO − 3 contents. Total viable count (TVC) and Escherichia coli (E. coli) counts in all the samples were high and the waters were not potable. The nutrient characteristics of the study area exhibited drastic temporal variation indicating highest concentration during the summer season compared to winter and rains. The persistence of dissolved oxygen (DO) deficit and very high biochemical oxygen demands (BOD) all along the water courses suggest that the deoxygenation rate of lotic water was much higher than reoxygenation. Hierarchical cluster analysis of the various physico-chemical and microbial parameters established three different zones and the most contaminated zone was found to be near the domestic sewage mixing points.

Research paper thumbnail of Anthropogenic Impact on Water Quality of Chilika Lagoon RAMSAR Site: a Statistical Approach

Wetlands Ecology and …, 2007

This paper investigated the spatiotemporal variability of water quality parameters (transparency,... more This paper investigated the spatiotemporal variability of water quality parameters (transparency, salinity, dissolved oxygen, nutrients viz. NH 3-N, NO 2-N, NO 3-N, PO 4 3-P, total nitrogen, total phosphorous and chlorophyll-a) in Chilika lagoon during 2001-2003 in order to better understand its ecological characteristics. Marked spatial and seasonal variations were detected with respect to almost all parameters studied. Northern sector of the lagoon is more affected by the anthropogenic stress from the catchments than the southern sector. Addition of nitrogen and phosphorous compounds to the lagoon mainly occurred through the drainage from agricultural lands and river run off during the early months of paddy cultivating seasons. Phytoplankton productivity of the lagoon was nitrogen limited, as suggested by nitrogen to phosphorous ratio. Processes affecting the water quality of the lagoon system included agricultural drainage, sewage intrusion, macrophyte litter fall and exchange of water between lagoon and the sea (Bay of Bengal). Further in depth study pertaining to quantification of exogenous material input and their disposal is recommended to ensure proper management of the lagoon and its resources.

Research paper thumbnail of Remote Monitoring of Sediment Dynamics in a Coastal Lagoon: Long-term Spatio-temporal Variability of Suspended Sediment in Chilika

Estuarine, Coastal and Shelf Science, 2016

Research paper thumbnail of Variability of nutrients and phytoplankton biomass in a shallow brackish water ecosystem (Chilika Lagoon, India)

Limnology, 2009

... KK Satapathy Environmental and Industrial Safety Section, IGACR (DAE), Kalpakkam 603102, Tami... more ... KK Satapathy Environmental and Industrial Safety Section, IGACR (DAE), Kalpakkam 603102, Tamilnadu, India BC Acharya Institute of Minerals and Materials Technology, Bhubaneswar 751013, India 123 ... TN (µg l-1) 200 300 400 500 600 700 800 900 g TP (µg l-1) ...

Research paper thumbnail of Phosphorus in the siliceous manganese ores of Nishikhal, Orissa

Research paper thumbnail of Sulphide mineralisation in parts of Eastern Ghats complex, Orissa

Research paper thumbnail of Mineral chemistry of manganese ores associated with Precambrian Eastern Ghats Complex of Andhra Pradesh-Orissa, India

Research paper thumbnail of Graphite mineralisation in Eastern Ghat migmatites around Nishikhal, south Orissa