Alkali Metasomatism and Th-REE Mineralization in the Choghart deposit, Bafq district, Central Iran

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Khalegh Khoshnoodi
Mehrdad Behzadi
Mohammad Gannadi-Maragheh
Mohammad Yazdi

Abstract

The Choghart iron oxide-apatite (IOA) deposit is located 124 km southeast of Yazd, in the Bafq district within the Central Iranian microcontinent. The Choghart deposit is hosted by the rhyolitic rocks of the Early Cambrian volcano-sedimentary sequence (the Esfordi formation). Both host rocks and the orebodies are crosscut by diabase dykes. Tectonically, the Choghart rhyolites represent the continental margin setting and the Choghart diabase dykes formed in the back-arcbasin environment, respectively, indicating that the evolution of the Bafq district is associated with subduction of Palaeotethys oceanic crust beneath the Central Iranian microcontinent followed by formation of continental arc related granitoids and rhyolites and then formation of back-arc basin diabase dykes. Similar to the other subduction-related rhyolites, the Choghart rhyolite is enriched in Th and LREE compared to Ia, Nb, and HREE.

The main host minerals of Th and REE in the Th-REE mineralization zone are thorite and sphene. Albitization is the most important alteration aspect related to Th-REE mineralization (mainly Th, La, Ce, Nd, and Y). In addition to albite, Th-REE mineralization is associated with actinolite, augite, diopside, minor microcline and orthoclase, plus magnetite, calcite, pyrite, rutile, and minor amounts of chalcopyrite. The negative Eu anomaly in Th mineralization zone, as well as the paragenetic occurrence of magnetite, pyrite and chalcopyrite with thorite suggest that Th-REE mineralization formed in relatively reduced condition. The presence of paragenetic calcite accompanied by thorite and sphene in the Th-REE mineralization zone indicates that Th and REE were likely transported by the carbonate complexes in the mineralizing fluids. The similarity betweenthe chondrite-normalized REE patterns of the host rhyolite and the Th-REE mineralization zone suggests that post-magmatic driven fluids of continental margin rhyolitic magma played an important role in Th-REE mineralization.

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References

AGHANABATI, A. (1998): Major sedimentary and structural units of Iran (map).− Int. Geosci., 7, 29–30.

AGHANABATI, A. (2008): Stratigraphy Encyclopedia of Iran- Precambrian to Silurian. Geological Survey Survey and Mineral Exploration of Iran.Tehran, 658p.

ALAVI, M. (1991): Tectonic map of the Middle East (scale 1:5,000,000).- Geological Survey and Mineral Exploration of Iran, Tehran.

BAGHERI, S. & STAMPFLI, G. M. (2008): The Anarak, Jandaq and Posht-e-Badam metamorphic complexes in Central Iran: new geological data, relationships and tectonic implications.-Tectp., 451, 123–155. doi: 10.1016/j.tecto.2007.11.047

BAU, M. & MÖLLER, P. (1992): Rare earth element fractionation in metamorphoge nic
hydrothermal calcite, magnesite and siderite.– Mineral. and Petrol., 45, 231–246. doi: 10.1007/BF01163114

CUNEY, M., EMETZ, A., MERCADIER, J. & MYKCHAYLOV, V. (2012): Uranium deposits associated with Na-metasomatism from central Ukraine: A review of some of the major deposits and genetic constraints.Ore Geology Reviews, 44, 82-106. doi:
10.1016/j.oregeorev.2011.09.007

DAHLKAMP, F. J. (1993): Uranium Ore Deposits.- Springer-Verlag, Berlin, 460 p. doi: 10.1007/978-3-662-02892-6

DAHLKAMP, F. J. (2009): Uranium Deposits of the world – Asia.– Springer-Verlag, Berlin, 493 p.

DALIRAN, F. (2002): Kiruna-type iron oxide-apatite ores and ‘apatites’ of the Bafq district, Iran, with an emphasis on the REE geochemistry of their apatites.- In: PORTER, T. M. (Ed.), Hydrothermal Iron Oxide Copper Gold and Related Deposits: A Global Perspective., 2. PGC Publishing, Adelaide, Australia, 303–320.

DALIRAN, F., STOSCH H. G. & WILLIAMS, P. A. (2009): Review of the Early Cambrian Magmatic and Metasomatic events and their bearing on the genesis of the Fe oxide-REE-apatite deposits (IOA) of the Bafq District, Iran.- In: WILLIAMS, et al. (eds.): Smart Science for Exploration and Mining, Proceedings of the 10th Biennial SGA Meeting, Townsville, Australia 17th–20th August.

DEHGHAN, A.R. (2011): Geological prospecting plan of the Choghart deposit, 1:4200, Report of Central Iron Ore Company (In Persian).

FELDMAN, G. K. (1926): About some varieties of spherulite quartz of the ZhovtaRichka mine.-Dnipropetrovsk: Bull Geol Mining circle of Dnipropetrovsk Mining Institute, 2.

FORSTER, H. & JAFARZADEH, A. (1994): The Bafq mining district in central iran a highly mineralized infracambrian volcanic field.- Econ. Geol., 89, 1697-1721. doi: 10.2113/gsecongeo.89.8.1697

FRANK, M. R., SIMON, A., PETTKE, T., CANDELA, P. & PICCOLI, P. (2011): Gold and copper partitioning in magmatic-hydrothermal systems at 800°C and 100 MPa.-Geochim. CosmochimActa, 75/9, 2470-2482.

HAGHIPOUR, A. (1977): Geological map of the Biabanak-Bafq area.- Geological Survey of Iran, scale 1:500000.

HAGHIPOUR, A. & PELISSIER, G. (1968): Geology of the Posht-e-Badam-Saghand area (east central Iran).- Iran Geological Survey Note 48, 144 p.

HUCKRIEDE, R., KURSTEN, M. & VENZLAFF, H. (1962): Zurgeologie des gebietszwischen Kerman und Saghand (Iran). Beih.- Geol. Jb., 53, 197 p.

HURTING, N. C. & WILLIAMS-JONES, A. E. (2014): An experimental study of the transport of gold through hydration of AuCl in aqueous vapour and vapour-like fluids.-Geochim. Cosmochim.Acta, 127, 305-325.

IAEA (2014): Uranium 2014; resources, production and demand, 504p.

KARGARANBAFGHI, F., NEUBAUER, F., GENSER, J., FAGHIH, A. & KUSKY, T. (2012): Mesozoic to Eocene ductile deformation of western Central Iran: From Cimmerian.- Tectp., 564–565, 83–100.

KINNAIRD, J.A.(1985): Hydrothermal alteration and mineralization of the alkaline anorogenic ring complexes of Nigeria.- African Earth Sci., 3, 229–252. doi: 10.1016/0899-5362(85)90038-7

LEAKE, B. E., WOOLEY, A. R., ARPS C.E.S., BIRCH, W. D., GILBERT, M. C., GRICE, J. D., HAWTHORNE, F. C., KATO, A., KISCH, H. J., KRIVOVICHEV, V. G., LINTHOUT, K., LAIRD, J., MANDARINO, J. A., MARESCH W. V., NICKEL, E. H., ROCK, N. M. S., SCHUMACHER, J. C., SMITH, D. C., STEPHENSON, N. C. N., UNGARETTI, L., WHITTAKER, E. J. W. & YOUZHI, G. (1997). Nomenclature of amphiboles: Report of the subcommittee on amphiboles of the International Mineralogical Association, Commission on new minerals and mineral names.– Am. Mineral., 82, 1019–1037.

MIGDISOV, A. A., BYCHKOV, A. Y., WILLIAMS-JONES, A. E. & VAN-HINSBERG, V. J. (2014): A predictive model for the transport of copper by HCl-bearing water vapour in ore-forming magmatic-hydrothermal systems: Implications for copper porphyry ore formation.-Geochim.Cosmochim. Acta, 129, 33-53. doi: 10.1016/j.gca.2013.12.024

MIRZAEI BENI, Z., EMAMI, M. H., SHEIKHZAKARIAEE, S. J. & NASR ESFAHANI, A. (2014): Petrography of plutonic rocks in the Late Cambrian (Rizu Series), Sechahun Iron oxide deposit, Bafq mining district, Central Iran.– Biodiversity and Environmental Sciences (JBES), 5/4, 610–616.

MOHAMMAD TORAB, F. (2008): Geochemistry and metallogeny of magnettite-apatite deposits of the Bafq mining district, central Iran.- Ph.d Thesis, Faculty of Energy and Economic Sciences, Technical university of Claustal, 131p.

MOORE, F. & MODABBERI, S. (2003): Origin of Choghart iron oxide deposit, Bafq mining district, Central Iran: new isotopic and geochemical evidence.– Journal of Sciences Islamic Republic of Iran, 14/3, 259–270.

MORIMOTO, N., FABRIES, J., FERGUSON, A. K., GINZBURG, I. V., ROSS, M., SEIFERT, F. A. & ZUSSMAN, J. (1988): Nomenclature of Pyroxenes.– Am. Mineral., 73, 1123–1133.

NADIMI, A. (2007): Evolution of the Central Iranian basement.- Int. Gondwana Res. 12, 324–333. doi: 10.1016/j.gr.2006.10.012

PIRAJNO, F. (2009): Hydrothermal Processes and Mineral Systems.- Springer, 1250 p. doi: 10.1007/978-1-4020-8613-7

PIRAJNO, F. (2013): Effects of metasomatism on mineral systems and their host rocks: alkali metasomatism, skarns, greisens, tourmalinites, rodingites, black-wall alteration and listvenites.- in: HARLOV, DE. & AUSTRHEIM (eds): Metasomatism and metamorphism: the role of fluids in crustal and upper mantle processes, Lecture Series in Earth Science, Springer, 203-251. doi: 10.1007/978-3-642-28394-9_7

POLLARD, PJ. (1983): Magmatic and postmagmatic processes in the formation of rocks associated with rare element deposits.- Trans Inst Min Metall, 92, B1–B9.

RAJABI, A. (2008): Geology, mineralogy, texture and structure, geochemistry and genesis of Chahmir Zn-Pb deposit, south of Behabad, Yazd Province.- M.Sc. thesis, Faculty of Science, TarbiatModares University, Iran.

RAJABI, A. (2012): Ore controlling parameters and genesis of sedimentaryexhalative Zn-Pb (SEDEX type) deposits, Zarigan-Chahmir Area, East of Bafq, Central Iran.- Ph.D. thesis, Faculty of Science, TarbiatModares University, Iran.

RAJABI, A., CANET, C., RASTAD, E. & ALFONSO, P. (2014): Basin evolution and stratigraphic correlation of sedimentary-exhalative Zn–Pb deposits of the Early Cambrian Zarigan-Chahmir basin, Central Iran.- Int. Ore Geol. Rev., 64, 328–353.

RAJABI, A., RASTAD, E., ALFONSO, P. & CANET C. (2012): Geology, ore facies and sulfur isotopes of the Koushk vent-proximal sedimentary-exhalative deposit, Posht-e-Badam block, Central Iran.- Int. Geol. Rev., 54, 1635–1648.

RAMEZANI, J. & TUCKER, R. (2003): The Saghand region, central Iran: U-Pb geochronology, petrogenesis and implications for Gondwana Tectonics.- American J. Sci., 303/3, 622-665. doi: 10.2475/ajs.303.7.622

REED, M. J., CANDELA, P. A. & PICCOLI, P. M. (2000): The distribution of rare earth elements between monzogranitic melt and the aqueous volatile phase in experimental investigations at 800°C and 200 MPa.- Contrib. Mineral. Petrol., 140, 251-262.

SAMANI, B. (1993): Saghand formation, a riftogenic unit of upper Precambrian in central Iran.- Int. Geosci., 6, 32–45.

SAUNDERS, A. D., TARNERY, J. (1991): Back-arc basins. In: Floyd, P.A. (Ed.), Oceanic Basalts. Blackie, Glasgow, pp. 219–263. doi: 10.1007/978-1-4615-3540-9_10

SCHANDL, E. S. & GORTON, M.P. (2002): Appplication of high field strength elements to discriminate tectonic setting in VMS environments. Economic Geology, 97,629–642.

SIMON, A. C., PETTKE, T., CANDELA, P. A., PICCOLI, P. M. & HEINRICH, C. A. (2004): Magnetite solubility and iron transport in magmatic-hydrothermal environments.-Geochim. Cosmochim.Acta, 68, 4905–4914. doi: 10.1016/j.gca.2004.05.033

SIMON, A. C., PETTKE, T., CANDELA, P. A., PICCOLI, P. M. & HEINRICH, C. A. (2005): Gold partitioning in melt vapor-brine systems.-Geochim. Cosmochim.Acta, 69, 3321-3335. doi: 10.1016/j.gca.2005.01.028

SIMON, A.C., PETTKE, T., CANDELA, P. A., PICCOLI, P. M. & HEINRICH, C. A. (2006): Copper partitioning in melt-vapor-brine-magnetite-pyrrhotite assemblage.-Geochim. Cosmochim.Acta, 70, 5583-5600. doi: 10.1016/j.gca.2006.08.045

SMITH, R. E., SMITH, S. E. (1976). Comments on the use of Ti, Zr, Y, Sr, K, P and Na inclassification of basaltic magmas. Earth and Planetary Science Letters 32, 114–120.

STAMPFLI, G. M. (2009): Terranes Map of the Western Tethysides.- UNIL, Université de Lausanne (open file).

STOSCH, H. G., ROMER, R. l., DALIRAN, F. & RHEDE, D. (2011): Uranium–lead ages of apatite from iron oxide ores of the Bafq District, East-Central Iran.- Mineral. Deposita., 46, 9-21. doi: 10.1007/s00126-010-0309-4

SUN, S. S. & MC DONOUGH, W. F. (1989): Chemical and isotopic systematics of oceanic basalts; implications for mantle composition and processes.– In: SAUNDERS, A. D. & NORRY, M. J. (eds.): Magmatism in the Ocean Basins. London, UK, Geological Society of London, 313–345. doi: 10.1144/GSL.SP.1989.042.01.19

TAGHIPOUR, S., KANANIAN, A. & SOMARIN, A. K.(2013): Mineral Chemistry and Alteration Parageneses of the Choghart Iron Oxide- apatite Occurrence, Bafq District, Central Iran.– Neues Jahrbuch für Geologie und Paläontologie, 269/3, 221–240.

TANATAR, I. I. (1925): New rocks of the Kryvy Rig iron ore basin: Part1.-InjenernyRabotnik, 7.

TITAYEVA, N. A. (1994): Nuclear geochemistry.- CRC press, 304p.

WILDE, A. (2013): Towards a model for albitite-type uranium.- J. Minerals, 3, 36-48. doi: 10.3390/min3010036

WINCHESTER, J. A., FLOYD, P. A. (1977): Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chem. Geol. 20, 325–343. doi: 10.1016/0009-2541(77)90057-2

WOOD, D. A. (1980): The application of a Th–Hf–Ta diagram to problems of tectonomagmatic classification and to establishing the nature of crustal contamination of basaltic lavas of the British Tertiary volcanic province. Earth Planet. Sci. Lett. 50, 11–30.

WOOD, S. A. (1990a): The aqueous geochemistry of rare earth elements and yttrium. 1. Review of available low-temperature data for inorganic complexes and the inorganic speciation of natural waters.- Chem. Geol., 82, 159-181.

WOOD, S. A. (1990b): The aqueous geochemistry of rare earth elements and yttrium. 2. Theoretical predictions of speciation in hydrothermal solutions to 350°C at saturation water vapor pressure.- Chem. Geol., 88, 99-125.

YAGHUBPUR, A. & MEHRABI, B. (1997): Koushk Zinc-Lead Deposit a typical black-shale-hosted deposit in Yazd State, Iran.- J. Sci., I.R.Iran, 8/2, 117–125.

ZAJACZ, Z., CANDELA, P. A., PICCOLI, P. M., WALLE, M. & SANCHEZ-VALLE, C. (2012): Gold and copper in volatile saturated mafic to intermediate magmas: Solubilities, partitioning, and implications for ore deposit formation.-Geochim. Cosmochim.Acta, 91, 140-159. doi: 10.1016/j.gca.2012.05.033

ZHOU, J. X. (1999): Geochemistry and Petrogenesis of Igneous Rocks Containing Amphibole and Mica: A Case Study of Plate Collision Involving Scotland and Himalayas. Science Press, New York and Beijing, pp. 41–72.