Abstract
U-rich pyrochlore (UO2 up to 18.63%) occurs along the magmatic bands as well as disseminated grains within rauhaugites of the Newania complex. UO2 appears to be primary as it seems mostly evenly distributed all over the grains, though in one grain it does show concentration in parts. Ta is also an important element in some pyrochlore grains and its concentration reaches up to 17.15%. High U and Th are responsible for bringing metamictization in the Newania pyrochlore. Newania carbonatite has a complex emplacement history; rauhaugite seems to have been replaced at 2200 Ma years followed by emplacement of ankeritic carbonatite at around 1500 Ma. Later during tectonic event pyrochlore was involved in reaction with hydrothermal fluid and at this stage Fe and FeS were deposited on the rims of pyrochlore grains. At the same time pyrochlore was subjected to hydrothermal alteration resulting in removal of Na, Ca and F leaving large vacancy in its A-site. Very few grains have escaped such alteration.
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References
Aroyo, M. I., Perez-Mato, J. M., Capillas, C., Kroumova, E., Ivantchev, S., Madariaga, G., Kirov, I. and Wondratschek, H. (2006) Bilbao Crystallographic Server: I. Databases and crystallographic computing programs. Zeitschrift für Kristallographie, v.221, pp.15–27.
Aroyo, M. I., Kirov, A., Capillas, C., Perez-Mato, J. M. and Wondratschek, H. (2006) Bilbao Crystallographic Server. II. Representations of crystallographic point groups and space groups. Acta Crystallographica Section A: Foundations of Crystallography, v.62, pp.115–128.
Aroyo, M. I., Perez-Mato, J. M., Orobengoa, D., Tasci, E., De La Flor, G. and Kirov, A. (2011) Crystallography online: Bilbao crystallographic server. Bulgarian Chemical Communications, v.43, pp.183–197.
Atencio, D., Gieré, R., Andrade, M. B., Christy, A. G. and Kartashov, P. M. (2010) The pyrochlore supergroup of minerals: Nomenclature. Canadian Mineralogist, v.48, pp.673–678.
Bonazzi, P., Bindl, L., Zoppo, M., Capitani, G.C. and Olmi, F. (2006) Singlecrystal diffraction and transmission electron microscopy studies of “silicified” pyrochlore from Narssarssuk, Julianehaab district, Greenland. American Mineral., v.91, pp.794–801.
Deans, T. and Powell, J.L. (1968) Trace elements and strontium isotopes in carbonatites, fluorites and limestones from India and Pakistan. Nature, v.218, pp.750–752.
Geisler, T., Berndt, J., Meyer, H. W., Pollok, K. and Putnis, A. (2004) Lowtemperature aqueous alteration of crystalline pyrochlore: correspondence between nature and experiment. Mineralogical Magazine, v.68, pp.905–922.
Gruau, G., Petibon, C. and Viladkar, S. (1995) Extreme isotopic signature in carbonatites from Newania, Rajasthan. Terra Nova 7, Abstract Suppl 1:336
Hogarth, D. D. (1977) Classification and nomenclature of the pyrochlore group. American Mineralogist, v.62, pp.403–410.
Hogarth, D.D. (1989) Pyrochlore, apatite and amphibole: distinctive minerals in carbonatite. In: K. Bell, (Ed.), Carbonatites: Genesis and Evolution. Unwin Hyman, london, pp.105–148.
Hogarth, D.D., Williams, C.T. and Jones, P. (2000) Primary zoning in pyrochlore group of minerals from carbonatites. Mineral. Mag., v.64(4), pp.683–897.
Jager, E., Niggli, E. and van der Veen, A.H. (1959) A hydrated bariumstrontium pyrochlore in a biotite rock from Panda Hill, Tanganyika. Mineral. Mag., v.32, pp.10–25.
Kjarsgaard, K.J. and Mitchell, R.H. (2008) Solubility of Ta in the system CaCO3–Ca(OH)2–NaTaO3–NaNbO3–F at 0.1 GPa: implications for the crystallization of pyrochlore-group minerals in carbonatites. Canadian Mineral., v.46, pp.981–990.
Kroumova, E., Aroyo, M. I., Perez-Mato, J. M., Kirov, A., Capillas, C., Ivantchev, S. and Wondratschek, H. W. (2003). Bilbao Crystallographic Server/: Useful Databases and Tools for Phase-Transition Studies. Phase Transitions, v.76, pp.155–170.
Lumpkin, G. R., Chakoumakos, B.C. and Ewing, R.C. (1986) Mineralogy and radiation effects of microlite from the Harding pegmatite, Taos County, New Mexico. Amer. Mineral., v.71, pp.569–588.
Mishra, S. P. (1982) New genetic model for base metals in the Aravalli Region, India. Symposium on Metallogeny of the Precambrian, I.G.C.P. Project no.91, pp.63–70
Nasraoui, M. and Bilal, E. (2000) Pyrochlores from the Lueshe carbonatite complex (Democratic Republic of Congo): a geochemical record of different alteration stages. Jour. Asian Earth Sci., v.18, pp.237–251.
Ray, J.S., Pande, K., Bhutani, R., Shukla, A.D., Rai, V. K., Kumar, A., Awasthi, S., Smitha, R. S. and Panda, D. K. (2013) Age and geochemistry of the Newania dolomite carbonatites, India: Implications for the source of primary carbonatite magma. Contrib. Mineral. Petrol., v.166, pp.1613–1632.
Redkin, A.F. and Borodulin, G. P. (2010) Pyrochlores as Indicators of the Uranium Bearing Potential of Magmatic Melts. DokladyAkademii Nauk, v.432, no.5, pp.664–667.
Schleicher, H., Todt, W., Viladkar, S.G. and Schmidt, F. (1997). Pb/Pb age determinations on the Newania and Sevattur carbonatites of India: evidence for multi-stage histories. Chemical Geol., v.140, pp.261–273.
Vandenborre, M.T. and Husson, E. (1983) Comparison of the Force Field in Various Pyrochlore Families. I. TheA2B2O7 Oxides. Journal of Solid State Chemistry, v.50, pp.362–371.
Vandenborre, M.T. and Husson, E. (1984) Comparison of the force field in various pyrochlore families. II. Phases presenting structural defects. Jour. Solid State Chemistry, v.53, pp.253–259.
Van Wambeke, L. (1965) A study of some niobium bearing minerals of the Lueshe carbonatite deposit (Kivu, Republic Congo) Report of Atomic Energy Community, Euratom, EUR 2110,e. pp.1–30.
Van Wambeke, L. (1971) Pandaite, baddeleyite and associated minerals from the Bingo niobium deposit, Kivu, DemocraticRepublic of Congo. Mineralium Deposita, v.6, pp.153–155.
Van Wambeke, L. (1978) Kalipyrochlore, a new mineral of the pyrochlore group. American Mineral., v.63, pp.528–530.
Verma, P.K. and Greiling, R.O. (1995) Tectonic evolution of the Aravalli Orogen (NW India): An inverted Proterozoic Rift Basin. Geol Rundsch 84:683–686.
Viladkar, S.G. and Pawaskar, P.B. (1989) Rare Earth Element abundances in carbonatites and fenites of the Newania complex, Rajasthan, India. Bull. Geol. Soc. Finland, v.61, pp.113–122.
Viladkar, S.G., Kienast, J.R. and Fourcade, S. (1993) Mineralogy of the Newania carbonatite, Rajsthan, India. IAGOD Symposium, Orleans, France, pp.55
Viladkar, S.G. and Ghose, I. (2002) U-rich pyrochlore in carbonatites of Newania, Rajasthan N. Jb. Miner Mh., v.3, pp.97–106.
Viladkar, S.G. and Bismayer, U. (2014) U-rich Pyrochlore from Sevathur Carbonatites, Tamil Nadu. Jour. Geol. Soc. India, v.83, pp.147–154.
Wall, F.C.T. Williams, C.T. and Woolley, A.R. (1996) Pyrochlore from weathered carbonatite at Lueshe, Zaire. Mineral. Mag., v.60, pp.731–750
Yaroshevskii, A.A. and Bagdasarov Yu, A. (2008) Geochemical Diversity of Minerals of the Pyrochlore Group. Geoch. Inter. 46, 12, pp.1322–1345.
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Viladkar, S.G., Bismayer, U. & Zietlow, P. Metamict U-rich pyrochlore of Newania carbonatite, Udaipur, Rajasthan. J Geol Soc India 89, 133–138 (2017). https://doi.org/10.1007/s12594-017-0576-0
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DOI: https://doi.org/10.1007/s12594-017-0576-0