Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-25T20:11:50.281Z Has data issue: false hasContentIssue false
  • English
  • Français

Magnetite-apatite deposits of the Bafq district, Central Iran: apatite geochemistry and monazite geochronology

Published online by Cambridge University Press:  05 July 2018

F. M. Torab  and
B. Lehmann
F. M. Torab*
Affiliation:
Department of Mining Engineering, Yazd University, Yazd, Iran Institute of Mineralogy and Mineral Resources, Technical University of Clausthal, 38678 Clausthal-Zellerfeld, Germany
B. Lehmann
Affiliation:
Institute of Mineralogy and Mineral Resources, Technical University of Clausthal, 38678 Clausthal-Zellerfeld, Germany
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The Bafq mining district is in the Early Cambrian Kashmar-Kerman volcano-plutonic arc in Central Iran and hosts important ‘Kiruna-type’ magnetite-apatite deposits. The hydrothermal magnetite-apatite mineralization occurs mostly as massive orebodies, metasomatic replacements, veins and stockworks. Apatite (low-Sr fluorapatite containing small amounts of hydroxyl) has undergone a partial hydrothermal overprint which involved leaching of Na, Cl and REE. The REE were remobilized into monazite (and minor allanite, parisite and xenotime) which nucleated as inclusions within apatite or as individual crystals. The monazites have very small ThO2 contents (usually <1 wt.%), but they occasionally show an inner core of high-Th monazite, with low-Th overgrowth rims. The chemical Th-U-total Pb dating of the high-Th monazites by electron microprobe analysis yields an isochron age of 515±21 Ma (initial PbO intercept = 68 ppm), or 529±21 Ma (forced initial PbO = 0), which is contemporaneous with the emplacement of the volcano-plutonic host rocks of the magnetite-apatite mineralization, as well as with widespread sedimentation of Late Proterozoic to Cambrian evaporitic rocks in Central Iran. The monazite age and the mineralogical and geochemical data suggest that the magnetite-apatite deposits are probably related to large-scale brine circulation induced by felsic magmatism during the Cambrian.

Keywords

Bafq districtIranmagnetiteapatitemonazite geochronologyREE
Type
Research Article
Information
Mineralogical Magazine , Volume 71 , Issue 3 , June 2007 , pp. 347 - 363
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Barton, M.D. and Johnson, D.A. (1996) Evaporiticsource model for igneous-related Fe oxide-(REE-Cu-Au-U) mineralization. Geology, 24, 259–262.2.3.CO;2>CrossRefGoogle Scholar
Barton, M.D. and Johnson, D.A. (2000) Alternative brine sources for Fe-oxide (-Cu-Au) systems: implications for hydrothermal alteration and metals Pp. 43–60 in: Hydrothermal Iron Oxide Coppergold & Related Deposits: A Global Perspective (Porter, T.M., editor), 1, PGC Publishing, Adelaide, Australia.Google Scholar
Belousova, E.A., Griffin, W.L., O’Reilly, S.Y. and Fisher, N.I. (2002) Apatite as an indicator mineral for mineral exploration: trace-element compositions and their relationship to host rock type. Journal of Geochemical Exploration, 76, 45–69.CrossRefGoogle Scholar
Bookstrom, A.A. (1977) The magnetite deposits of El Romeral, Chile. Economic Geology, 72, 1101–1130.CrossRefGoogle Scholar
Cocherie, A. and Albarède, F. (2001) An improved UTh- Pb age calculation for electron microprobe dating of monazite. Geochimica et Cosmochimica Acta, 65, 4509–4522.CrossRefGoogle Scholar
Cocherie, A. and Legendre, O. (2007) Potential minerals for determining U-Th-Pb chemical age using electron microprobe. Lithos, 93, 288–309.CrossRefGoogle Scholar
Cocherie, A., Mezeme, E.B., Legendre, O., Fanning, C.M., Faure, M. and Rossi, P. (2005) Electronmicroprobe dating as a tool for determining the closure of Th-U-Pb systems in migmatitic monazites. American Mineralogist, 90, 607–618.CrossRefGoogle Scholar
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 Pp. 303–320 in: Hydrothermal Iron Oxide Coppergold & Related Deposits: A Global Perspective (Porter, T.M., editor), 2, PGC Publishing, Adelaide, Australia.Google Scholar
Förster, H.J. and Harlov, D.E. (1999) Monazite-(Ce)- huttonite solid solutions in granulite-facies metabasites from the Ivrea-Verbano Zone, Italy. Mineralogical Magazine, 63, 587–594.CrossRefGoogle Scholar
Förster, H. and Jafarzadeh, A. (1994) The Bafq mining district in Central Iran – a highly mineralized Infracambrian volcanic field. Economic Geology, 89, 1697–1721.Google Scholar
Frietsch, R. (1978) On the magmatic origin of iron ores of the Kiruna type. Economic Geology, 73, 478–485.CrossRefGoogle Scholar
Gleason, J.D., Marikos, M.A., Barton, M.D. and Johnson, D.A. (2000) Neodymium isotopic study of rare earth element sources and mobility in hydrothermal Fe oxide (Fe-P-REE) systems. Geochimica et Cosmochimica Acta, 64, 1059–1068.CrossRefGoogle Scholar
Haghipour, A. (1977) Geological Map of the Biabanak- Bafq Area (scale 1:500,000). Geological Survey of Iran.Google Scholar
Harlov, D.E. and Förster, H.J. (2003) Fluid-induced nucleation of (Y+REE)-phosphate minerals within apatite: Nature and experiment. Part II. Fluorapatite. American Mineralogist, 88, 1209–1229.Google Scholar
Harlov, D.E., and ersson, U.B., Förster, H.J., Nys Tröm, J.O., Dulski, P. and Broman, C. (2002) Apatitemonazite relations in the Kiirunavaara magnetiteapatite ore, northern Sweden. Chemical Geology, 191, 47–72.CrossRefGoogle Scholar
Hildebrand, R.S. (1986) Kiruna-type deposits: their origin and relationship to intermediate subvolcanic plutons in the Great Bear Magmatic Zone, northwest Canada. Economic Geology, 81, 640–659.CrossRefGoogle Scholar
Hitzman, M.W. (2000) Iron oxide-Cu-Au deposits: what, where, when, and why Pp. 9–25 in: Hydrothermal Iron Oxide Copper-gold & Related Deposits: A Global Perspective (Porter, T.M., editor), 2, PGC Publishing, Adelaide, Australia.Google Scholar
Hitzman, M.W., Oreskes, N. and Einaudi, M.T. (1992) Geological characteristics and tectonic setting of Proterozoic iron oxide (Cu-U-Au-REE) deposits. Precambrian Research, 58, 241–287.CrossRefGoogle Scholar
Hogarth, D.D. (1989) Pyrochlore, apatite and amphibole: distinctive minerals in carbonatite Pp. 105–148 in: Carbonatites: Genesis and Evolution (Bell, K., editor). Unwin Hyman, London.Google Scholar
Husseini, M.I. and Husseini, S.I. (1990) Origin of the Infracambrian salt basins of the Middle East Pp. 279–292 in: Classic Petroleum Provinces (Brooks, J., editor). Special Publication, 50. Geological Socety, London.Google Scholar
Jercinovic, M.J. and Williams, M.L. (2005) Analytical perils (and progress) in electron microprobe trace element analysis applied to geochronology: Background acquisition, interferences, and beam irradiation effects. American Mineralogist, 90, 526–546.CrossRefGoogle Scholar
Ludwig, K.R. (2001) Users manual for ISOPLOT/EX, rev. 2.49 – A geochronological toolkit for Microsoft Excel. Berkeley Geochronology Center, Special Publication, No. 1a. Berkeley, California, USA.Google Scholar
Montel, J.M., Foret, S., Veschambre, M., Nicollet, C. and Provost, A. (1996) Electron microprobe dating of monazite. Chemical Geology, 131, 37–53.CrossRefGoogle Scholar
Moore, F. and Modabberi, S. (2003) Origin of Choghart iron oxide deposit, Bafq mining district, Central Iran: new isotopic and geochemical evidence. Journal of Science, Islamic Republic of Iran, 14, 259–269. Naslund, H.R., Aguirre, R., Dobbs, F.M., Henriquez, F.J. and Nys Tröm, J.O. (2000) The origin, emplacement, and eruption of ore magmas. Pp. 135–139 in: IX Congreso Geologico Chileno, 2, Sociedad geológica de Chile.Google Scholar
Nys Tröm, J.O. and Henriquez, F. (1994) Magmatic features of iron ores of the Kiruna type in Chile and Sweden: ore textures and magnetite geochemistry. Economic Geology, 89, 820–839.Google Scholar
Pan, Y., Fleet, M.E. and Macrae, N.D. (1993) Oriented monazite inclusions in apatite porphyroblasts from the Hemlo gold deposit, Ontario, Canada. Mineralogical Magazine, 57, 697–707.CrossRefGoogle Scholar
Parak, T. (1975) Kiruna iron ores are not ‘intrusivemagmatic ores of the Kiruna type’. Economic Geology, 70, 1242–1258.CrossRefGoogle Scholar
Parrish, R.R. (1990) U-Pb dating of monazite and its application to geological problems. Canadian Journal of Earth Sciences, 27, 1431–1450.CrossRefGoogle Scholar
Piccoli, P.M. and Candela, P.A. (2002) Apatite in igneous systems Pp. 255–292 in: Phosphates: Geochemical, Geobiological, and Materials Importance (Kohn, M.J., Rakovan, J. and Hughes, J.M., editors). Reviews in Mineralogy and Geochemistry, 48, Mineralogical Society of America, Washington, D.C. Google Scholar
Poitrasson, F., Chenery, S. and Shepherd, T.J. (2000) Electron microprobe and LA-ICP-MS study of monazite hydrothermal alteration: Implications for U-Th-Pb geochronology and nuclear ceramics. Geochimica et Cosmochimica Acta, 64, 3283–3297.CrossRefGoogle Scholar
Pyle, J.M., Spear, F.S. and Wark, D.A. (2002) Electron microprobe analysis of REE in apatite, monazite and xenotime: Protocols and pitfalls Pp. 337–362 in: Phosphates: Geochemical, Geobiological, and Materials Importance (Kohn, M.J., Rakovan, J. and Hughes, J.M., editors). Reviews in Mineralogy and Geochemistry, 48, Mineralogical Society of America, Washington, D.C. Google Scholar
Pyle, J.M., Spear, F.S., Wark, D.A., Daniel, C.G. and Storm, L.C. (2005) Contributions to precision and accuracy of monazite microprobe ages. American Mineralogist, 90, 547–577.CrossRefGoogle Scholar
Ramezani, J. and Tucker, R.D. (2003) The Saghand region, Central Iran: U-Pb geochronology, petrogenesis and implications for Gondwana tectonics. American Journal of Science, 303, 622–665.CrossRefGoogle Scholar
Samani, B.A. (1988) Metallogeny of the Precambrian in Iran. Precambrian Research, 39, 85–106.CrossRefGoogle Scholar
Schandl, E.S. and Gorton, M.P. (2004) A textural and geochemical guide to the identification of hydrothermal monazite: Criteria for selection of samples for dating epigenetic hydrothermal ore deposits. Economic Geology, 99, 1027–1035.CrossRefGoogle Scholar
Sillitoe, R.H. and Burrows, D.R. (2002) New field evidence bearing on the origin of the El Laco magnetite deposit, Northern Chile. Economic Geology, 97, 1101–1109.Google Scholar
Stöcklin, J. (1968) Structural history and tectonics of Iran: A review. Bulletin of the American Association of Petroleum Geologists, 52, 1229–1258.Google Scholar
Stormer, J.C. Jr., Pierson, M.L. and Tacker, R.C. (1993) Variation of F and Cl X-ray intensity due to anisotropic diffusion in apatite during electron microprobe analysis. American Mineralogist, 78, 641–648.Google Scholar
Suzuki, K. and Adachi, M. (1991) Precambrian provenance and Silurian metamorphism of the Tsubonosawa paragneiss in the South Kitakami terrane, Northeast Japan, revealed by the chemical Th-U-total Pb isochron ages of monazite, zircon and xenotime. Geochemical Journal, 25, 357–376.CrossRefGoogle Scholar
Torab, F.M. and Lehmann, B. (2006) Iron oxide-apatite deposits of the Bafq district, Central Iran: an overview from geology to mining. World of Mining – Surface and Underground, 58, 355–362.Google Scholar
Williams, M.L., Jercinovic, M.J., Goncalves, P. and Mahan, K. (2006) Format and philosophy for collecting, compiling, and reporting microprobe monazite ages. Chemical Geology, 225, 1–15.CrossRefGoogle Scholar
Zharkov, M.A. (1984) Paleozoic Salt Bearing Formations of the World. Springer-Verlag, Berlin, 427 pp.CrossRefGoogle Scholar
Zhu, C. and Sverjensky, D.A. (1991) Partitioning of FCl- OH between minerals and hydrothermal fluids. Geochimica et Cosmochimica Acta, 55, 1837–1858.CrossRefGoogle Scholar
Ziemann, M.A., Förster, H.J., Harlov, D.E. and Frei, D. (2005) Origin of fluorapatite-monazite assemblages in a metamorphosed, sillimanite-bearing pegmatoid, Reinbolt Hills, East Antartica. European Journal of Mineralogy, 17, 567–579.CrossRefGoogle Scholar