Refine your search
Collections
Co-Authors
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Chandan Kumar, B.
- Petrography and Geochemistry of Proterozoic Clastic Sediments of Naragund, Karnataka:Implications for their Provenance and Tectonic Setting
Abstract Views :168 |
PDF Views:125
Authors
Affiliations
1 Department of Geology, Karnatak Science College, Dharwad-580001, IN
2 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
1 Department of Geology, Karnatak Science College, Dharwad-580001, IN
2 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
Source
International Journal of Earth Sciences and Engineering, Vol 9, No 5 (2016), Pagination: 1983-1988Abstract
The Proterozoic clastic sediments exposed at Naragund, Karnataka belongs to the Kaladgi Group, which are unconformably under lain (Eparchean unconformity) and surrounded by Archaean gneiss. The rocks are characteristically bedded with individual beds having variable thickness. Based on the color variation, four varieties of quartz arenite have been distinguished as the grey, white, red and pink quartz arenites. The primary sedimentary structure like stratification, ripple marks, current bedding and graded bedding are commonly seen in the study area. The petrographic analysis has revealed that the clastic sediments are quartz-rich and were primarily derived from felsic sources. The chemical composition of 10 quartz arenite samples corroborates the petrographic observations. The provenance and geodynamic studies indicate that the clastic sediments were derived predominantly from felsic source region and were deposited in a passive margin type tectonic setting.Keywords
Clastic Sediments, Petrography, Geochemistry, Quartz Arenites, Provenance, Tectonic Setting.Full Text
- Petrography and Geochemistry of the Neoarchaean Greywackes from Central Part of the Dharwar-Shimoga Greenstone Belt, Western Dharwar Craton
Abstract Views :488 |
PDF Views:219
Authors
Affiliations
1 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
2 Department of Geology, Central University of Kerala, Kasaragod-671123, IN
1 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
2 Department of Geology, Central University of Kerala, Kasaragod-671123, IN
Source
International Journal of Earth Sciences and Engineering, Vol 10, No 4 (2017), Pagination: 898-902Abstract
Greywackes are the most dominant of litho units in the central part of the Dharwar-Shimoga greenstone belt of the Western Dharwar Craton. They are texturally immature with angular to subangular detrital sand grains with 25 to 60% matrix. Quartz forms the main detrital component and is mostly monocrystalline with distinct undulatory extinction. Amongst feldspars, plagioclase feldspar exceeds K-feldspar. Micas occur as large and small flakes that are oriented. Biotite is the main mica mineral. The phyllite, chert, quartzite and felsic volcanic rock fragments are common. The matrix is generally made up of chlorite, sericite, clay to silt-sized quartz and feldspar. In Q-F-L classification diagram, these rocks plot in the fields of quartz wackes and quartzose wackes. The silica content varies between 60.93 and 68.07 wt% and alkalies between 3.69 and 5.21 (Table 2), and compositionally they are comparable to andesite and dacite. Moderately higher values of Fe2O3 (av. 8.16 wt%), MgO (av. 7.89 wt%) and K2O/Na2O (av. 1.65) indicate a matrix with an abundance of chlorite, biotite, clays and iron oxides. The petrographic and geochemical evidence suggests that these greywackes were derived from the source which had felsic to intermediate composition, with a moderate relief exposed to arid and dry palaeoclimatic conditions. As compared to greywackes of the northern part of the Dharwar-Shimoga greenstone belt, the greywackes of the present study area (central part) have higher values of MgO, Fe2O3+MgO, K2O/Na2O, Al2O3/Na2O and lower values of Al2O3, Na2O, and SiO2/MgO.Keywords
Greywacke, Petrography, Geochemistry, Provenance, Dharwar-Shimoga Greenstone Belt.Full Text
References
- Swami Nath, J. and Ramakrishnan, M., “Early Precambrian Supracrustals of Southern Karnataka (A) present classification and correlation”, Geological Survey India Memoir, 112, PP.261-276, 1981.
- Naqvi, S. M., Sawkar, R. H., Subba Rao, D. V., Govil, P.K. and Gnaneswar Rao, T. “Geology, geochemistry and tectonic setting of Archean greywackes from Karnataka nucleus, India”, Precambrian Research, 39, PP.193-216,1988. https://doi.org/10.1016/0301-9268(88)90042-3
- Srinivasan, S. V. and Naha, K., “Archaean sedimentation in the Dharwar Craton, Southern India”, Proceedings of the National Academy of Sciences, PP.63 (A), 1993.
- Hegde, V. S. and Chavadi, V. C., “Geochemistry of late Archaean metagreywackes from the Western Dharwar Craton, South India: Implications for provenance and nature of the Late Archaean crust”, Gondwana Research, 15, PP.178-187, 2009. https://doi.org/10.1016/j.gr.2008.09.006
- Devaraju, T. C., Sudhakar, T. L., Kaukonen, R. J., Viljoen, R. P., Alapiett, T.T., Ahmed, S. A. and Sivakumar, S., “Petrology and geochemistry of greywackes from Goa-Dharwar sector, western Dharwar Craton: implications for volcanoclastic origin”, Journal of Geollogical Society of India, 75, PP. 465–487, 2010. ISSN: 0016-7622
- Ugarkar, A. G., Chandan Kumar, B. and Manuvachari, T. B., “Lithology and geochemistry of metavolcanics and metasediments of northern part of the Dharwar- Shimoga schist belt, Western Dharwar Craton”, Indian Mineralogist, 46(2), PP.162-178, 2012. ISSN: 0019-5928
- Ugarkar, A. G., Chandan Kumar, B., Malapur, M. A., Manuvachari, T. B. and Kerr, A.C., “Petrography and Geochemistry of Archaean Greywackes from Northern Part of the Dharwar-Shimoga Greenstone Belt, Western Dharwar Craton: Implications for Nature of Provenance”, Journal of Geological Society of India, 89, 2017 (In press). ISSN: 0016-7622
- Harinadha Babu, P., Ponnuswamy, M. and Krishnamurthy, K. V., “Shimoga belt”, Memoirs of Geological Survey of India, 112, PP.199-218, 1981.
- Ziauddin, M., Roy, A., Biswas, S. K. and Gururaja Rao, T. P., “Volcanism in the younger Dharwar rocks in Medur, Dharwar district, Karnataka”, Journal of Geological Society of India, 19, PP. 321-325, 1978. ISSN: 0016-7622
- Le Bas, M. J., Le Maitre, R. W., Streckeinsen, A. and Zanettin, B. E., “A chemical classification of volcanic rocks based on the total alkali-silica diagram”, Journal of Petrology, 27, PP.745-750, 1986. https://doi.org/10.1093/petrology/27.3.745
- Cullers, R. L., Barret, T., Carlson, R. and Robinson, B., “REE and mineralogic changes in Holocene soil and stream sediments: a case study in the Wet Mountains, Colorado, U.S.A”, Chemical Geology, 63, PP.275–297, 1987. https://doi.org/10.1016/0009-2541(87)90167-7
- Wronkiewicz, D. J. and Condie, K. C., “Geochemical of Archaean shales from the Witwatersrand Supergroup, South Africa source-area weathering and provenance”, Geochimica et Cosmochimica Acta, 51, PP.2401-2416, 1987. https://doi.org/10.1016/0016-7037(87)90293-6
- Jacobson, V. and Blum, J. D., “Relationship between mechanical erosion and atmospheric CO2 consumption in the New Zealand South Alps”, Journal of Geological Society of America, 31, PP. 865-868, 2003. https://doi.org/10.1130/G19662.1
- Suttner, L. J. and Dutta, P. K., “Alluvial sandstone composition and paleoclimate - 1: Framework mineralogy”, Journal of Sedimentary Petrology, 56(3), PP. 329-345, 1986. ISSN: 0022-4472
- Nesbitt, H. W. and Young, G. M., “Early Proterozoic climates and plate motion inferred from major element chemistry of lutites”, Nature, 299, PP. 715-717, 1982. doi:10.1038/299715a0
- Nesbitt, H. W. and Young, G. M., “Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations”, Geochimica et Cosmochimica Acta, 48, PP.1523-1534, 1984. https://doi.org/10.1016/0016-7037(84)90408-3
- Shaw, D. M., “A review of K-Rb fractionation trends by covariance analysis”, Geochimica et Cosmochimica Acta, 32, PP. 573-601, 1968. https://doi.org/10.1016/0016-7037(68)90050-1
- Floyd, P. A. and Leveridge, B. E., “Tectonic environment of the Devonian Gramscatho basin, south Cornwall: framework mode and geochemical evidence from turbiditic sandstones”, Journal of Geological Society of London, 144, PP. 531-542, 1987. https://doi.org/10.1144/gsjgs.144.4.0531
- Nesbitt, H. W. and Young, G. H., “Formation and diagenesis of weathering profile”, Journal of Geology, 97, PP.129-147, 1989. https://doi.org/10.1086/629290
- Potter, P. E., Maynard, J. B. and Depetris, P. J., “Mud and mudstones: Berlin”, Springer-Verlag, 2005. ISBN 978-3-540-27082-9
- Lamaskin, T. A., Dorsey, R. J. and Vervoort, J. D., “Tectonic controls on mudrock geochemistry, Mesozoic rocks of eastern Oregon an western Idaho, USA: Implications for cordilleran tectonics”, Journal of Sedimentary Research, 78, PP.765-783, 2008. ISSN 15271404
- Basalt-Andesite-Dacite-Rhyolite (BADR) Metavolcanic Sequence from the Central Part of Dharwar-Shimoga Greenstone Belt, Western Dharwar Craton
Abstract Views :157 |
PDF Views:119
Authors
Affiliations
1 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
2 Department of Geology, Central University of Kerala, Kasaragod-671123, IN
1 Department of Studies in Geology, Karnatak University, Dharwad-580003, IN
2 Department of Geology, Central University of Kerala, Kasaragod-671123, IN
Source
International Journal of Earth Sciences and Engineering, Vol 10, No 1 (2017), Pagination: 106-110Abstract
The petrographic and major element geochemical characteristics clearly suggest that the metavolcanic rocks of Medur Formation in the central part of the Dharwar-Shimoga greenstone belt comprise basalt, andesite, dacite and rhyolite (BADR) sequence. These metavolcanic rocks are metamorphosed to greenschist-amphibolite facies. The basalts show mixed tholeiitic and komatiitic composition. The andesites are mainly tholeiitic, while dacite and rhyolites are calc alkaline nature. Good correlation exists between SiO2 and major oxides, which suggests that these metavolcanic series (BADR) compositions are genetically inter-related and were derived probably from differentiation of magma at different depths.Keywords
Metavolcanics, Petrography, Geochemistry, Dharwar-Shimoga Greenstone Belt, Dharwar Craton.Full Text
- Mineralogy and Geochemistry of Desur Clay Deposit Hosted Within the Peninsular Gneiss, Northern Part of the Dharwar Craton of South India
Abstract Views :115 |
PDF Views:121
Authors
T. B. Manuvachari
1,
R. L. Jayappagol
1,
S. R. Kulakarni
1,
N. A. Parry
1,
B. Chandan Kumar
1,
A. G. Ugarkar
1
Affiliations
1 Department of Geology, Karnatak University, Dharwad-580003, IN
1 Department of Geology, Karnatak University, Dharwad-580003, IN
Source
International Journal of Earth Sciences and Engineering, Vol 9, No 3 (2016), Pagination: 1012-1017Abstract
The clay deposit which is hosted within the Peninsular Gneisses at Desur in Belgaum District of Karnataka is underlain by partially weathered granitic gneiss and overlain by soil horizon. Infra-Red and major oxide composition of clay samples indicate that kaolinite is the dominant clay mineral with subordinate abundance of illite. Quartz, chlorite, muscovite and montmorillonite also occur, but in minor abundance as admixtures in these clays. Clays occur as non-linear horizontal bodies which do not support the hydrothermal process for their formation. While the observed gradation from top to bottom is soil, clays and a weathered zone with fragments of precursor rock and hard and compact gneiss, which essentially indicates in-situ development of the weathered or residual clay profile. Geochemical comparison of Desur clays with that of the host granitic gneiss reveals that SiO2, Fe2O3 CaO, Na2O and K2O oxides were mobile, while Al2O3 was immobile during the process of weathering. Kaolinite rich clay deposit of Desur was formed by the residual weathering of precursor granitic gneiss under tropical to sub-tropical humid conditions.Keywords
Clays, Residual Deposit, Peninsular Gneiss, Khanapur Granitic Pluton.Full Text
- Mineralogy and Geochemistry of Clay Deposit of Gadag Greenstone Belt, Dharwar Craton, India:Implications for Residual Deposition
Abstract Views :159 |
PDF Views:114
Authors
Affiliations
1 Department of Geology, Karnatak University, Dharwad-580003, IN
1 Department of Geology, Karnatak University, Dharwad-580003, IN
Source
International Journal of Earth Sciences and Engineering, Vol 9, No 1 (2016), Pagination: 110-115Abstract
The clay deposit occurs near Majjur-Varvi area, which is a large syncline, called as the Majjur syncline, bounded to the NE and SW by steep thrust faults, namely Sortur and Suganhalli discontinuities of the well-known Gadag greenstone belt, Dharwar Craton in southern India. The lowest part of the stratigraphy of this area comprises schistose metabasalts, followed by felsic metavolcanics, conglomerates and greywackes. The clay bodies occur within the felsic metavolcanic rocks. The X-Ray diffraction and Infra-Red studies indicate that kaolinite is the dominant clay mineral, with subordinate illite. Quartz and plagioclase are the associated minerals. The clays are characterized by higher contents of SiO2, CaO, Na2O, K2O, MgO and lower contents of Al2O3 compared to kaolinite mineral, which could be due to the presence of quartz, plagioclase and illite with these clays. Clays occur as non-linear horizontal bodies which do not support the hydrothermal process for their formation. While the cross sections in the quarries resemble shale. The observed gradation from top to bottom is soil, clays and a weathered zone with fragments of precursor rock, which essentially indicates in-situ development of the weathered or residual profile. Plagioclase was altered to clay while quartz was dissolved into solution and carried away from the site of weathering. Kaolinite clays in the study area occur as residual clay bodies that were formed by in-situ chemical weathering of felsic metavolcanics under tropical to sub-tropical humid and acidic conditions.Keywords
Clays, Residual Deposit, Gadag Greenstone Belt, Dharwar Craton.Full Text