Petrography and Mineral Chemistry of Metamorphogenic Magnetite in the Layered Sill of the JC Pura Schist Belt, Karnataka, India — Oak Academic Publishing
Research ArticleOpen AccessGoogle Scholar indexed
Petrography and Mineral Chemistry of Metamorphogenic Magnetite in the Layered Sill of the JC Pura Schist Belt, Karnataka, India
Department of Geology, Bangalore University, Bangalore, India
,
Department of Geology, Bangalore University, Bangalore, India
,
Department of Geology, Bangalore University, Bangalore, India
1 Department of Geology, Bangalore University, Bangalore, India
2 Department of Geology, Bangalore University, Bangalore, India
3 Department of Geology, Bangalore University, Bangalore, India
JC Pura schist belt has gained scope recently with reports of nickel, magnetite, PGEs, and traces of gold. The layered sill in the schist belt is a linear patch of ultramafic sequences (peridotite and pyroxenite) with metamorphogenic magnetite mineralization. The metamorphogenic magnetite appears as interbands in layered sequences and as veins in serpentinite. The present study focuses on understanding the characteristics of metamorphogenic magnetite by petrographic and EPMA analysis. The study found that the precursor chromite grains are transformed into Cr-magnetite and magnetite in the spinel transformation system due to metamorphism and hydrothermal alteration. The Cr, Mg, Al, and Ni are depleted during transformation, and Fe is enriched. The Cr-magnetite appears homogenous in the vein due to serpentinization, indicating prograde greenschist to amphibolite facies metamorphism, and the area has suffered an episodic metamorphic process. The results of Cr-magnetite cation proportions of Cr fall within ishkulite variety data range of 0.10 - 0.50 apfu (atoms per formula unit). Cr-magnetite variety Ishkulite represents an additional miscibility gap in the Cr-Fe 3+ transformation series other than ferrite chromite and chrome magnetite. The transformation process primarily involves the oxidation of chromium and the reduction of iron. The oxidation of chromite by highly oxidizing fluids with increasing pressure and temperature alters to Cr-magnetite, where chromium in the +3 state oxidizes to the +6 state, forming soluble chromate ions and diffusing with Fe 3+ . Then, it transforms into magnetite due to reducing conditions. Cr-magnetite vein indicates the potential for chromite deposits in the area, and hydrothermal altered magnetites could be a source for hosting valuable precious metals like gold and PGEs. Further investigations are needed to assess the mineralization potential and its extent.
Latypov, R.M., Namur, O., Bai, Y., Barnes, S.J., Chistyakova, S., Holness, M.B., et al . (2024) Layered Intrusions: Fundamentals, Novel Observations and Concepts, and Controversial Issues. Earth - Science Reviews , 249, Article 104653. https://doi.org/10.1016/j.earscirev.2023.104653
Arndt, N.T. (1986) Differentiation of Komatiite Flows. Journal of Petrology , 27, 279-301. https://doi.org/10.1093/petrology/27.2.279
Lahaye, Y., Arndt, N., Byerly, G., Chauvel, C., Fourcade, S. and Gruau, G. (1995) The Influence of Alteration on the Trace-Element and Nd Isotopic Compositions of Komatiites. Chemical Geology , 126, 43-64. https://doi.org/10.1016/0009-2541(95)00102-1
Jayananda, M., Kano, T., Peucat, J. and Channabasappa, S. (2008) 3.35Ga Komatiite Volcanism in the Western Dharwar Craton, Southern India: Constraints from Nd Isotopes and Whole-Rock Geochemistry. Precambrian Research , 162, 160-179. https://doi.org/10.1016/j.precamres.2007.07.010
Mukherjee, R., Mondal, S.K., Rosing, M.T. and Frei, R. (2010) Compositional Variations in the Mesoarchean Chromites of the Nuggihalli Schist Belt, Western Dharwar Craton (India): Potential Parental Melts and Implications for Tectonic Setting. Contributions to Mineralogy and Petrology , 160, 865-885. https://doi.org/10.1007/s00410-010-0511-5
Prabhakar, B.C. and Namratha, R. (2014) Morphology and Textures of Komatiite Flows of J.C. Pura Schist Belt, Dharwar Craton. Journal of the Geological Society of India , 83, 13-20. https://doi.org/10.1007/s12594-014-0002-9
Sappin, A.-A., Houlé, M.G., Lesher, C.M., McNicoll, V., Vaillancourt, C. and Kamber, B.S. (2016) Age Constraints and Geochemical Evolution of the Neoarchean Mafic-Ultramafic Wabassi Intrusive Complex in the Miminiska-Fort Hope Greenstone Belt, Superior Province, Canada. Precambrian Research , 286, 101-125. https://doi.org/10.1016/j.precamres.2016.09.018
Banerjee, R., Biswas, B.K. and Mondal, S.K. (2023) Origin of Alteration Patterns in Accessory Chromites from the Kudada Metaperidotites, East Singhbhum District (Jharkhand, India). Journal of the Geological Society of India , 99, 345-356. https://doi.org/10.1007/s12594-023-2317-x
Venkata Dasu, S.P., Ramakrishnan, T.M. and Mahabaleswar, B. (1991) Sargur-dharwar Relationship around the Komatiite-Rich Jayachamarajapura Greenstone Belt in Karnataka. Journal Geological Society of India , 38, 577-592. https://doi.org/10.17491/jgsi/1991/380604
Prabhakar, B.C. and Namratha, R. (2015) A Note on the Layered Dunite-Peridotite-Pyroxenite Sill in the Komatiitic Milieu of J.C. Pura Belt, Dharwar Craton. Journal of Geological Society of India , 85, 120-121.
Santhosh, S., Dayanand, B.G. and Prabhakar, B.C. (2023) Geochemistry of Layered Ultramafic Rocks in J.C. Pura Schist Belt, Dharwar Craton, Karnataka, India. Open Journal of Geology , 13, 189-202. https://doi.org/10.4236/ojg.2023.132009
Rashmi, B. N., Prabhakar, B. C., Gireesh, R. V., Nijagunaiah, R., and Ranganath, R. M. (2009) Nickel Anomalies in Ultramafic Profiles of Jayachamarajapura Schist Belt, Western Dharwar Craton. Current Science , 96, 1512-11517. http://www.jstor.org/stable/24104781
Fayazudeen, P.J., Sahoo, H.B., Das, P., Datta, D. and Taye, S.K. (2019) Reconnaissance Survey for Ni-PGE and Gold between Rampura and Gollarahatti Areas of J.C. Pura Mafic-Ultramafic Belt, Hassan District, Karnataka (Stage-G4). Technical Report, Geological Survey of India.
Talukdar, D., Singh, A., Raul, A.K., Mandal, N., Mohanty, S.N., Mohanty, M. and Korakoppa, M.M. (2018) Occurrence of Precious Metals in Ultramafic Hosted Magnetite of J. C. Pura Belt, Western Dharwar Craton, Karnataka. Indian Journal of Geoscience , 72, 175-184.
Ramakrishnan, M., Venkata Dasu, S.P. and Kroener, A. (1994) Middle Archaean Age of Sargur Group by Single Grain Zircon Dating and Geochemical Evidence for the Clastic Origin of Metaquartzite from J. C. Pura Greenstone Belt, Karnataka. Journal Geological Society of India , 44, 605-616. https://doi.org/10.17491/jgsi/1994/440602
Naqvi, S.A., Govil, P.K. and Rogers, J.J.W. (1981) Chemical Sedimentation in Archaean-Early Proterozoic Greenstone Belts of the Dharwar Craton, India. In: Glover, J.E. and Groves, D.I., Eds., Archean Geology : Second International Symposium , Perth , No. 7, Geological Society of Australia, 245-254.
Chardon, D., Choukroune, P., Jayananda, M. (1996) Strain Patterns, Décollement and Incipient Sagducted Greenstone Terrains in the Archaean Dharwar Craton (South India). Journal of Structural Geology , 18, 991-999, 1001-1004. https://doi.org/10.1016/0191-8141(96)00031-4
Philpotts, A. and Ague, J. (2009) Principles of Igneous and Metamorphic Petrology. 2nd Edtion, Cambridge University Press. https://doi.org/10.1017/cbo9780511813429
Jayananda, M., Duraiswami, R.A., Aadhiseshan, K.R., Gireesh, R.V., Prabhakar, B.C., Kafo, K., et al . (2016) Physical Volcanology and Geochemistry of Palaeoarchaean Komatiite Lava Flows from the Western Dharwar Craton, Southern India: Implications for Archaean Mantle Evolution and Crustal Growth. International Geology Review , 58, 1569-1595. https://doi.org/10.1080/00206814.2016.1172350
Pandey, R., Rao, N.V.C., Pandit, D., Sahoo, S. and Dhote, P. (2017) Imprints of Modal Metasomatism in the Post-Deccan Subcontinental Lithospheric Mantle: Petrological Evidence from an Ultramafic Xenolith in an Eocene Lamprophyre, NW India. Geological Society , London , Special Publications , 463, 117-136. https://doi.org/10.1144/sp463.6
Hatert, F., Mills, S.J., Pasero, M. and Williams, P.A. (2013) CNMNC Guidelines for the Use of Suffixes and Prefixes in Mineral Nomenclature, and for the Preservation of Historical Names. European Journal of Mineralogy , 25, 113-115. https://doi.org/10.1127/0935-1221/2013/0025-2267
Bosi, F., Biagioni, C. and Pasero, M. (2019) Nomenclature and Classification of the Spinel Supergroup. European Journal of Mineralogy , 31, 183-192. https://doi.org/10.1127/ejm/2019/0031-2788
Florent, H., Mélina, M., Julie, C., Antoine, T., Julien, B., Ricardo, T., et al . (2017) Identification of Cr-Magnetite in Neoproterozoic Serpentinites Resulting of Cr-Spinel Alteration in a Past Hydrothermal System: Aït Ahmane ultramafic unit (Bou Azzer ophiolite, Anti Atlas, Morocco). 19 th EGU General Assembly , EGU 2017, Proceedings from the Conference , Vienna, 23-28 April 2017, 13876. https://ui.adsabs.harvard.edu/abs/2017EGUGA..1913876H/abstract
Barnes, S.J. (2000) Chromite in Komatiites, II. Modification during Greenschist to Mid-Amphibolite Facies Metamorphism. Journal of Petrology , 41, 387-409. https://doi.org/10.1093/petrology/41.3.387
Ahmed, A.H. and Surour, A.A. (2016) Fluid-Related Modifications of Cr-Spinel and Olivine from Ophiolitic Peridotites by Contact Metamorphism of Granitic Intrusions in the Ablah Area, Saudi Arabia. Journal of Asian Earth Sciences , 122, 58-79. https://doi.org/10.1016/j.jseaes.2016.03.010
Hodel, F., Macouin, M., Trindade, R.I.F., Araujo, J.F.D.F., Respaud, M., Meunier, J.F., et al . (2020) Magnetic Properties of Ferritchromite and Cr‐magnetite and Monitoring of Cr‐Spinels Alteration in Ultramafic and Mafic Rocks. Geochemistry , Geophysics , Geosystems , 21, GC009227. https://doi.org/10.1029/2020gc009227
Ziemniak, S.E. and Castelli, R.A. (2003) Immiscibility in the Fe 3 O 4 -FeCr 2 O 4 Spinel Binary. Journal of Physics and Chemistry of Solids , 64, 2081-2091. https://doi.org/10.1016/s0022-3697(03)00237-3
Diella, V., Ferrario, A. and Rossetti, P. (1994) The Magnetite Ore Deposits of the Southern Aosta Valley: Chromite Transformed during an Alpine Metamorphic Event. Ofioliti , 19, 247-256.
Rossetti, P., Gatta, G.D., Diella, V., Carbonin, S., Della Giusta, A. and Ferrario, A. (2009) The Magnetite Ore Districts of the Southern Aosta Valley (Western Alps, Italy): A Mineralogical Study of Metasomatized Chromite Ore. Mineralogical Magazine , 73, 737-751. https://doi.org/10.1180/minmag.2009.073.5.737
Giusta, A.D., Carbonin, S. and Umberto, R. (2011) Chromite to Magnetite Transformation: Compositional Variations and Cation Distributions (Southern Aosta Valley, Western Alps, Italy). Periodico di Mineralogia , 80. 1-17. https://doi.org/10.2451/2011PM0001
Barnes, S.J. and Roeder, P.L. (2001) The Range of Spinel Compositions in Terrestrial Mafic and Ultramafic Rocks. Journal of Petrology , 42, 2279-2302. https://doi.org/10.1093/petrology/42.12.2279
Sergeyeva, N.G. (1969) Ishulite under Electronic Microscope. International Geology Review , 11, 401-405. https://doi.org/10.1080/00206816909475068
Malitch, K.N. and Auge, T. (1998) The Composition of Inclusions in Osmium Minerals as an Indicator of the Formation Conditions of the Guli Ultramafic Massif. Doklady Earth Sciences , 361A, 812-814.
Ishkulite. https://www.mindat.org/min-9875.html
Irvine, T.N. (1967) Chromian Spinel as a Petrogenetic Indicator: Part 2. Petrologic Applications. Canadian Journal of Earth Sciences , 4, 71-103. https://doi.org/10.1139/e67-004
Cameron, E.N. (1975) Postcumulus and Subsolidus Equilibration of Chomite and Coexisting Silicates in the Eastern Bushveld Complex. Geochimica et Cosmochimica Acta , 39, 1021-1033. https://doi.org/10.1016/0016-7037(75)90044-7
Roeder, P.L. and Campbell, I.H. (1985) The Effect of Postcumulus Reactions on Composition of Chrome-Spinels from the Jimberlana Intrusion. Journal of Petrology , 26, 763-786. https://doi.org/10.1093/petrology/26.3.763
Scowen, P.A.H., Roeder, P.L. and Helz, R.T. (1991) Reequilibration of Chromite within Kilauea Iki Lava Lake, Hawaii. Contributions to Mineralogy and Petrology , 107, 8-20. https://doi.org/10.1007/bf00311181
Rollinson, H. (1995) Composition and Tectonic Settings of Chromite Deposits through Time; Discussion. Economic Geology , 90, 2091-2092. https://doi.org/10.2113/gsecongeo.90.7.2091