Copper deposits in Khetri copper belt are hosted in the proterozoic sequence of rocks belonging to Ajabgarh group of Delhi supergroup situated in foot hill zone of Aravalli mountain range North-West, India. Khetri copper belt is about 100？km long NE-SW trending metallogenic province, starting from Singhana in the north to Sangarava in the south. The study area is the northern Khetri copper belt 190 km SW of Delhi,？the capital city of India. In the present work an attempt has been made to determine the mode of occurrence and nature of mineralization with special emphasis on mineragraphic study of copper ores. The ore bodies are found in the form of multiple lodes regionally but locally in the forms of veins, stringers, dissemination, sporadic, cavity filling and replacement. Enriched mineralized zones are localized along the contact of Alwar and Ajabgarh group. Copper, the main entity in the belt occurs？dominantly as sulphides, oxides, carbonates and sulphosalts mineral hosted in pelitic and psammitic rocks. Pyrrhotite, pyrite, magnetite and sphalerite are the other ore mineral associated with the copper ore in a considerable amount. From the textural, structural and multigenerational minerals, mineral assemblage studies,？it is assumed that deposit has undergone metamorphism and multi-stage mineralization. Replacement has a profound influence on mineralization in the northern Khetri copper deposits.
References
[1]
Roy Chowdhury, M.K. and Das Gupta, S.P. (1965a) On the Nature of Geology and Mineralisation in the Khetri Copper Belt, Rajasthan. Proc. Nat. Inst. Sci., 31, 188-198.
[2]
Roy Chowdhury, M.K. and Das Gupta, S.P. (1965b) Ore-Localization in the Khetri Copper Belt, Rajasthan, India. Economic Geology, 60, 69-88.
https://doi.org/10.2113/gsecongeo.60.1.69
[3]
Mukherjee, A.K. (1966) Study of Ore Minerals from Kolihan Section of Khetri Copper Belt, Jhunjhunu Dt.; Rajasthan. Sci. Cul., 32, 250-254.
[4]
Mukherjee, A.D. (1972) Study of a Copper-Iron Sulphide Mineral (Cu 0.13 Fe 0.92 S 1.00) from the Sulphide Ores of Kollhan Section, Khetri Copper Belt, Rajasthan. Geological Society of India, 13, 185-189.
[5]
Rao, N.K. and Rao, G.V.U. (1968) Ore Microscopic Study of Copper Ore from Kolihan, Rajasthan, India. Economic Geology, 63, 277-287.
https://doi.org/10.2113/gsecongeo.63.3.277
[6]
Deb, S. and Mukherjee, A.D. (1969) Mackinawites from Madhan-Kudhan and Kolihan Sections of Khetri Copper Belt, Rajasthan. Proceedings of the National Academy of Sciences, India, 35A, 533-541.
[7]
Sarkar, S.C. and Dasgupta, S. (1980) Geologic Setting, Genesis and Transformation of the Sulphide Deposits in the Northern Part of the Khetri Copper Belt, Rajasthan, India—An Outline. Mineral. Deposita, 15, 117-137.
https://doi.org/10.1007/BF00206508
[8]
Mukherjee, A.D. and Sen, P.P. (1991) Compositional Variations in Mackinawites from the Chandmari Mine of Khetri Copper Belt, Rajasthan. Journal of the Geological Society of India, 38, 96-100.
[9]
Chen, W.T., Zhou, M.F., Li, X., Gao, J.F. and Hou, K. (2015) In-Situ LA-ICP-MS Trace Elemental Analyses of Magnetite: Cu-(Au, Fe) Deposits in the Khetri Copper Belt in Rajasthan Province, NW India. Ore Geology Reviews, 65, 929-939.
https://doi.org/10.1016/j.oregeorev.2014.09.035
[10]
Baidya, A.S., Sen, A. and Pal, D.C. (2018) Textures and Compositions of Cobalt Pentlandite and Cobaltian Mackinawite from the Madan-Kudan Copper Deposit, Khetri Copper Belt, Rajasthan, India. Journal of Earth System Science, 127, 56.
https://doi.org/10.1007/s12040-018-0954-z
[11]
Sinha-Roy, S. (1984) Precambrian Crustal Interaction in Rajasthan, NW India. Indian Journal of Earth Sciences, 11, 84-91.
[12]
Roy, A.B. and Kataria, P. (1999) Precambrian Geology of the Aravalli Mountain and Neighbourhood: Analytical Update of Recent Studies. In: Kataria, P., Ed., Seminar on Geology of Rajasthan: Status and Perspective, Mohanlal Sukhadia University, Udaipur, 1-56.
[13]
Roy, A.B. and Jakhar, S.R. (2002) Geology of Rajasthan (Northwest India) Precambrian to Recent. Scientific Publishers, Jodhpur, 421.
[14]
Gupta, P., Guha, D.B. and Chattopadhyay, B. (1998) Basement-Cover Relationship in the Khetri Copper Belt and the Emplacement Mechanism of the Granite Massifs, Rajasthan. Journal of the Geological Society of India, 52, 417-432.
[15]
Heron, A.M. (1923) Geology of Western Jaipur. Record Geological Survey of India, 54, 345-397.
[16]
Dasgupta, S.P. (1968) Structural History of Khetri Copper Belt, Jhunjhunu and Sikar Districts, Rajasthan. Memoirs of the Geological Survey of India, 98, 1-170.
[17]
Singh, S.P. (1988) Stratigraphy and Sedimentation Pattern in the Proterozoic Delhi Supergroup, Northwestern India. Memoirs Geological Society of India, 7, 193-206.
[18]
Kaur, G. and Mehta, P.K. (2007) Geochemistry and Petrogenesis of Jasrapura Granitoids, North Khetri Copper Belt, Rajasthan: Evidence for Island Arc Magmatism. Journal of the Geological Society of India, 69, 319-330.
[19]
Kaur, P., Chaudhri, N., Biju-Sekhar, S. and Yokoyama, K. (2006) Electron Probe Microanalyser Chemical Zircon Ages of the Khetri Granitoids, Rajasthan, India: Record of Widespread Late Palaeoproterozoic Extension-Related Magmatism. Current Science, 90, 65-73.
[20]
Kaur, P., Chaudhri, N., Hofmann, A.W., Raczek, I., Okrusch, M., Skora, S. and Baumgartner, L.P. (2012) Two-Stage, Extreme Albitization of A-Type Granites from Rajasthan, NW India. Journal of Petrology, 53, 919-948.
https://doi.org/10.1093/petrology/egs003
[21]
Das Gupta, S. (1978) Sedimentary Structures in the Precambrian Delhi Supergroup Rocks and Their Significance. Indian Journal of Earth Sciences, 5, 177-182.
[22]
LAl, R.K. and Shukla, R.S. (1975) Low-Pressure Regional Metamorphism in the Northern Portion of the Khetri Copper Belt, Rajasthan, India. Neues Jahrbuch für Mineralogie Abhandlungen, 124, 294-325.
[23]
Lal, R.K. & Ackermand, D. (1981) Phase Petrology and Polyphase Andalusite-Sillimanite Type Regional Metamorphism in Pelitic Schist of the Area around Akwali, Khetri Copper Belt, Rajasthan, India. Neues Jahrbuch fur Minineralogie, Abhandlungen, 141, 161-185.
[24]
Naha, K., Mukhopadhyay, D.K. and Mohanty, R. (1988) Structural Evolution of the Rocks of the Delhi Group around Khetri, Northeastern Rajasthan. In: Roy, A.B., Ed., Precambrian of the Aravalli Mountain, Geol. Soci. Ndia, Mem. No. 7, Rajasthan, 207-245.
[25]
Pant, N.C., Kundu, A. and Joshi, S. (2008) Age of Metamorphism of Delhi Supergroup Rocks-Electron Microprobe Ages from Mahendragarh District, Haryana. Journal of the Geological Society of India, 72, 365-372.
[26]
Knight, J., Lowe, J., Joy, S., Cameron, J., Merrillees, J., Nag, S., Shah, N., Dua, G. and Jhala, K. (2002) The Khetri Copper Belt, Rajasthan: Iron Oxide Copper-Gold Terrane in the Proterozoic of NE India. In: Porter, T.M., Ed., Hydrothermal Iron Oxide Copper-Gold and Related Deposits: A Global Perspective, 2, PGC, Adelaide, 321-341.
[27]
Ineson, P.R. (2014) Introduction to Practical Ore Microscopy. Routledge, New York. https://doi.org/10.4324/9781315841205
[28]
Kumar, D., Bahuguna, P.P., Villuri, M.V.G., Alam, M.S. and Panigrahi, D.C. (2014) Subsidence Study for Kolihan Copper Mine at Khetri Copper Complex, Rajasthan.
[29]
MECL (1995) Geological Report on Exploration for Copper Ore in Chandmari Intervening Block, Khetri Copper Belt, District-Jhunjhunu, Rajasthan.
[30]
Zafar, M. (1971) Contribution to Geochemistry of the Khetri Copper Belt, District Jhunjhuno, Rajasthan, India. Doctoral Dissertation, Aligarh Muslim University.
[31]
Pant, N.C., Kumar, S., Panday, M., Bajaj, A.K., Kandu, A., Joshi, S. and Shimyaphy, R.V.S. (2015) New Insights on the Genesis and Controls of Mineralization in Khetri Copper Belt and Adjacent Low Grade Cu Mineralization, Northwestern Indian Shield. Geological Survey of India, Special Publication, 101, 109-128.
[32]
Das Gupta, S.P. (1970) Sulfide Deposits of Saladipura, Khetri Copper Belt, Rajasthan. Economic Geology, 65, 331-339. https://doi.org/10.2113/gsecongeo.65.3.331
[33]
Ramdohr, P. (1955) Die Erzmineralien und ihre Verwachsungen. Akademie Verlag, Berlin.
[34]
Schwartz, G.M. (1927) Intergrowths of Chalcopyrite and Cubanite: Experimental Proof of the Origin of Intergrowths and Their Bearing on the Geologic Thermometer. Economic Geology, 22, 44-61. https://doi.org/10.2113/gsecongeo.22.1.44
[35]
Buerger, N.W. and Buerger, M.J. (1934) Crystallographic Relations between Cubanite Segregation Plates, Chalcopyrite Matrix and Secondary Chalcopyrite Twins. American Mineralogist, 19, 289-303.
[36]
Edwards, A.B. (1954) Textures of the Ore Minerals and Their Significance. Australasian Inst. Mining and Met.
[37]
Einaudi, M.T. (1977) Environment of Ore Deposition at Cerro De Pasco, Peru. Economic Geology, 72, 893-924. https://doi.org/10.2113/gsecongeo.72.6.893
[38]
Wu, I. and Peterson, U. (1977) Geochemistry of Tetrahedrite and Mineral Zoning at Casapalca, Peru. Economic Geology, 72, 993-1016.
https://doi.org/10.2113/gsecongeo.72.6.993
[39]
Knight, L.E. (1977) A Thermochemical Study of Alunite, Enargite, Luzonite, and Tennantite Deposits. Economic Geology, 72, 1321-1336.
https://doi.org/10.2113/gsecongeo.72.7.1321
Anthony, J.W., Bideaux, R.A., Bladh, K.W. and Nichols, M.C. (1990) Handbook of Mineralogy, Volume I. Elements, Sulfides, Sulfosalts. Mineral Data Publishing, Tucson, 588.
[42]
Hurlbut, B.J. (1985) Experimental and Computational Investigation of Strain-Softening in Concrete. Doctoral Dissertation, University of Colorado, Denver.
[43]
Li, X.C., Zhou, M.F., Williams-Jones, A.E., Yang, Y.H. and Gao, J.F. (2018) Timing and Genesis of Cu-(Au) Mineralization in the Khetri Copper Belt, Northwestern India: Constraints from in Situ U-Pb Ages and Sm-Nd Isotopes of Monazite-(Ce). Mineralium Deposita, 1-16.
