Mineralogy, geochemistry, fluid inclusions and Cu mineralization factors in the Ismailabad copper deposit, NE of Saveh, Urmia Dokhtar magmatic arc

Document Type : Original Article

Authors

1 Department of geology, Faculty of Earth Sciences, Lorestan University, Khorramabad, Iran

2 Department of geology of minerals and groundwater resources, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

10.48308/esrj.2025.106146

Abstract

Introduction
The Ismailabad copper deposit is located in the 55 km NE of Saveh, Central Iran. It is situated in the middle-northern part of the Urmia-Dakhtar magmatic arc (UDMA) of Iran. The Cenozoic volcanic units in the middle part of the UDMA around Saveh host several Cu-Au-Ag-Fe deposits, (Heidari et al, 2022), Narbaghi (Fazli et al, 2019), Rangerz (Zamanian et al, 2021), Zarandiyeh (Yousefi and Alipour-asll, 2019) and Koh Peng (Rajabpour et al, 2017, 2018). General studies in the middle part of the UDMA show the importance of mantle metasomatism in the formation of intrusive rocks. Based on U-Pb dating, this magmatic complex crystallized in the upper Eocene (Nouri et al, 2018).
Although there are many signs of old mining, mineral indices and Cu-Au-Ag deposits that are temporally and spatially related to Eocene magmatism in this area, but compared to other areas such as Arasbaran and Kerman belts, it has received less attention from researchers. It has been tried to understand the factors controlling of the copper mineralization based on the field geology, petrology, structure and texture, mineralogy and paragenesis of ore minerals, geochemistry and microthermometry of fluid inclusions. This research can be used to improve the exploration criteria of this type of deposit in the central part of UDMA and other similar places.
Materials and Methods
Different rock units from geological sections were used. Petrographic and mineralogical studies were conducted on 23 thin and thin- polished sections. In order to conduct geochemical studies of ore samples, 15 samples were analyzed by the ICP-OES method in the Iran Minerals Research and Processing Center. Also, to determine the characteristics of the ore-forming fluid, petrographic and microthermometric studies were conducted on two calcite mineral samples in the laboratory of Tarbiat Modares University.
 
Results and Discussion
The host rock for Cu-mineralization in the area is volcanic and volcano-sedimentary units of Eocene age that affect intrusive masses of granitic, monzonite, and gabbro-diorite. These host rocks have been affected by siliceous-carbonate, propylitic-chloritic, sericitic, and intermediate argillic alteration with different intensities. Mineralization occurs in the form of sulfide-oxide veins.Primary minerals include chalcopyrite, pyrite, tennantite, tetrahedrite, ologist, and magnetite, and secondary minerals include chalcocite, coveolite, azurite, malachite, chrysocolla, goethite, and limonite, which were deposited in the endogenous, secondary enrichment, and oxidant stages. The main textures of ore minerals include vein-veinlet, disseminated, open space filling, brecciated, replacement and coloform. The association of copper sulphide minerals such as chalcopyrite, chalcocite, covellite with pyrite and sulfosalts such as tennantite and tetrahedrite is the characteristics of epithermal deposits (Hedenquist, 2015). Microthermometric studies of fluid inclusion indicate that the homogenization temperature of 140.3 to 330℃, which according to Arribas et al. (1995) characterize fluid flow in the deep levels of hydrothermal systems. The salinity is 11.4 to 17.8 %wt. NaCl and the density is 0.78 to 1.05 g/cm3. The depth-pressure diagram (Fournier, 1999) shows that this process probably occurred at a depth of about 100 to 500 meters below the underground water level and hydrostatic pressure of 130 to 20 bar. In subvolcanic environments, meteoric waters, under the influence of physicochemical processes (temperature > 370 °C and lithostatic pressure), form complexes with sulfide anions (SO4-2 and HS-) and, to some extent, chloride, and these complexes have played an active role in transporting copper and accompanying elements (Pirajno, 2009). The processes of boiling, mixing and surface dilution of fluids are one of the important factors of the instability of chloride and sulfide complexes that lead to the simultaneous formation of Fe and Cu ore minreals. Sudden decrease of pressure in the fractures of the area is responsible for the formation of sulfide phases in the final stages of mineralization. There is an obvious overlap between the temperature and salinity range of mineralization in the Ismailabad deposit with the manto-type deposits.
Conclusion
The low-sulfidation epithermal Cu mineralization in the area is associated with Oligo-Miocene intrusive bodies and Eocene volcanic rocks, which is controlled by northwest-southeast trending faults. Copper mineralization occurred in the form of vein-veinlet and is associated with hydrothermal alteration including of siliceous-carbonate, argillic, propylitic, and sericitic. The mineralization includes hypogene, supergene and oxidant zones. In the hypogene zone, sulfide phases are mainly pyrite, chalcopyrite, and is associated with ologist, hematite, and magnetite. In the supergene zone, chalcocite and covellite are occured on the margin of primary sulfides. In the oxidan zone, malachite, azurite, chrysocolla and iron hydroxides have been formed. Cu shows highest correlation to the Ag, S, Sb, As, Ca, and Sc respectively. The instability of sulfide and chloride complexes leads to the simultaneous precipitation of Fe and Cu and the formation of sulfide phases in the last stage of mineralization. It has been significantly affected by the phenomenon of boiling, mixing and dilution of basin evaporation brines. Based on the values obtained from homogeneous temperature and salinity, the mixing of magma waters with meteoric waters and basin evaporation brines have played a role in the formation of ore minerals. Geological, mineralogical, alteration, and fluid inclusion data indicate that the occurance of manto-type mineralization.

Keywords

Main Subjects

References

Afshooni, S.Z., Mirnejad, H., Esmaeily, D. and Asadi, H.H., 2013. Mineral chemistry of hydrothermal biotite from the Kahang porphyry copper deposit (NE Isfahan), Central Province of Iran. Ore Geology Reviews, v. 54(1), p. 214-232. https://doi.org/10.1016/j.oregeorev.2013.04.004
Aghazadeh, M., Badrzadeh, Z. and Castro, A., 2015. Petrogenesis and U-Pb SHRIMP dating of Tarom plutons, Iran. Quarterly Journal of Geosciences, v. 24, p. 3-20 (In Persian with English abstract). https://doi.org/10.22071/gsj.2015.42373
Alavi, M., 1991. Tectonic map of the Middle East, Tehran. Geological Survey of Iran.
Alavi, M., 1994. Tectonics of the Zagros orogenic belt of Iran: New data and interpretations. Tectonophysics, v. 229(3), p. 211-238. https://doi.org/10.1016/0040-1951(94)90030-2
André-Mayer, A.S., Leroy, J., Bailly, L., Chauvet, A., Marcoux, E., Grancea, L., Llosa, F. and Rosas, J., 2002. Boiling and vertical mineralization zoning: A case sltudy from the Apacheta low-sulfidation epithermal gold-silver deposit, south Peru. Mineralium Deposita, v. 37, p. 452-464. https://doi.org/10.1007/s00126-001-0247-2
Arribas, A., Cunningham, O., Rytuba, J., Rye, O., Kelly, W., Podwysocki, W., Mckee, E. and Tosdal, R., 1995. Geology, geochronology, fluid inclusions, and isotope geochemisltry of Rodalquilar Au alunite deposit, Spain. Economic Geology, v. 90, p. 795-822. https://doi.org/10.2113/gsecongeo.90.4.795
Arvin, M., Pan, Y., Dargahi, S., Malekizadeh, A. and Babaei, A., 2007. Petrochemistry of the Siah-Kuh granitoid stock southwest of Kerman, Iran: Implications for initiation of Neo-Tethys subduction. Journal of Asian Earth Sciences, v. 30, p. 474-489. https://doi.org/10.1016/j.jseaes.2007.01.001
Ayati, F., Yavuz, F., Asadi, H., Richards, J.P. and Jourdane, F., 2013. Petrology and geochemistry of calc-alkaline volcanic and subvolcanic rocks, Dalli porphyry coppergold deposit, Markazi province, Iran. International Geology Review, v. 55, p. 158–184. https://doi.org/10.1080/00206814.2012.689640
Azizi, H., Chung, S.L., Tanaka, T. and Asahara, Y., 2011. Isotopic dating of the Khoy metamorphic complex (KMC); northwestern Iran: a significant revision of the formation age and magma source. Precambrian Research, v. 185(3-4), p. 87-94. https://doi.org/10.1016/j.precamres.2010.12.004
Beane, R.E., 1983. The Magmatic-Meteoric Transition. Geothermal Resources Council, Special Report, v. 13, p. 245-253.
Buckley, V.J.E., Sparks, R.S.J. and Wood, B.J., 2006. Hornblende dehydration reactions during magma ascent at Soufrière Hills Volcano, Montserrat. Contributions to Mineralogy and Petrology, v, 151(2), p. 121-140. https://doi.org/10.1007/s00410-005-0060-5
Caillat, C., Dehlavi, P. and Martel, J.B., 1978. Geologie de la region de Saveh (Iran): contribution à l’étude du volcanisme et du plutonisme tertiaires de la zone de l’Iran central. Ph. D. Thesis, Université Scientifique et Médicale de Grenoble, 325 p.
Chrisltie, A.B., Simpson, M.P., Brathwaite, R.L., Mauk, J.L. and Simmons, S.F., 2007. Epithermal Au-Ag and related deposits of the Hauraki goldfield, Coromandel volcanic zone, New Zealand. Economic Geology, v. 102, p. 785-816. https://doi.org/10.2113/gsecongeo.102.5.785
Dolatshahi, S., Zamanian, H., Karimzadeh Somarin, A. and Yang, X., 2019. Petrology, geochemistry and tectonic setting of the intrusive mass associated with Rangraz copper deposit (North of Saveh, central part of Urumieh-Dokhtar magmatic arc). Petrology, v. 10, p. 79-98 (In Persian). https://doi.org/10.22108/ijp.2019.116329.1131
Fan, H.R., Groves, D.I., Mikucki, E.J. and Mc Naughton, N.J., 2000. Contrasting fluid types at the Nevoria gold deposit in the Southern Cross greenstone belt, Western Australia: Implications of auriferous fluids depositing ores within and Archean banded iron- formation. Economic Geology, v. 95(7), p. 1527-1536. https://doi.org/10.2113/gsecongeo.95.7.1527
Fazli, N., 2015. Geology, mineralogy, geochemistry and genesis of North Narbaghi epithermal deposit, northeast of Saveh, M. Sc. Thesis, Tarbiat Modares University, 201p (In Persian).
Fazli, N. and Ghaderi, M., Lentz, D. and Li, J., 2019. Geology, alteration, mineralization, and geochemistry of the North Narbaghi epithermal Ag-Cu deposit, northeast Saveh, Iran. Quarterly Journal of Geosciences, v. 28, p. 13-22. (In Persian with English abstract). https://doi.org/10.22071/gsj.2018.97142.1246
Firoozbakht, M.S., Ghaderi, M. and Tajeddin, H., 2018. Geology and mineralization in the Lak base metal (-Au) deposit, south Buin Zahra. Proceedings of the 10th National Symposium of Iranian Society of Economic Geology, University of Isfahan, Isfahan, Iran, v. 2, p. 256-264. (In Persian with English abstract)
Fournier, R.O., 1999. Hydrothermal processes related to movement of fluid from plastic into brittle rock in the magmatic-epithermal environment. Economic Geology, v. 94, p. 1193-1212. https://doi.org/10.2113/gsecongeo.94.8.1193
Geological survey of Iran, 1989. Geological map of Zaviyeh. Scale 1/100,000, v. 624.
Ginibre, C. and Wörner, G., 2007. Variable parent magmas and recharge regimes of the Parinacota magma system (N. Chile) revealed by Fe, Mg and Sr zoning in plagioclase. Lithos, v. 98, p. 118-140. https://doi.org/10.1016/j.lithos.2007.03.004
Goudarzi, M., Zamanian, H., Klötzli, U. and Ullah, M., 2024. Evidence of boiling in ore-forming process based on quartz textures and fluid inclusions studies, a case study in Mamouniyeh Cu deposit, Iran. EGU General Assembly 2024, Vienna, Austria, EGU24-8552. https://doi.org/10.5194/egusphere-egu24-8552
Haas, J.L., 1976. Thermodynamic properties of the coexisting phases and thermodynamic properties of the NaCl component in boiling NaCl solutions. U.S. Geological Survey Bulletin, v. 1421, p.1-71.
Haghipour, A. and Aghanabati, A., 1989. Geological map of Iran at a scale of 1:250,000. Geological and Mineral Exploration Organization of the country (In Persian).
Hassanzadeh, J., Stockli, D.F., Horton, B.K., Axen, G.J., Stockli, L.D., Grove, M., Schmitt, A.K. and Walker, J.D., 2008. U-Pb zircon geochronology of late Neoproterozoic–Early Cambrian granitoids in Iran: Implications for paleogeography, magmatism, and exhumation history of Iranian basement. Tectonophysics, v. 451, p. 70-96. https://doi.org/10.1016/j.tecto.2007.11.062
Hedenquist, J.W., 2015. Porphyry copper potential in Mexico: Transitions from epithermal lithocaps to veins and tops of porphyry deposits. Extended abstract. AIMMGM Presentation, Acapulco, Mexico, p. 1-8.
Heidari, S.M., Safavy, S., Akbarpour, A., Hassanlou, A. and Mohaghegh, B. 2022. Geology, structure and mineralization of Cu (±Au) hydrothermal magmatic deposits of Saveh-Razan region. Scientific Quarterly Journal of Geosciences, v. 32(2), p. 89-104 (In Persian). https://doi.org/10.22071/gsj.2021.276571.1894
Hesami, K., Jamali, F. and Tabassi, H., 2003. Major Active Faults of Iran, Scale 1:2500000. International Institute of Earthquakes Engineering and Seismology, Tehran.
Housh, T.B. and Luhr, J.F., 1991. Plagioclase-melt equilibria in hydrous systems. American Mineralogist, v. 76, p. 477-492.
Humphreys, M.C.S., Blundy, J.D. and Sparks, R.S.J., 2006. Magma Evolution and Open-System Processes at Shiveluch Volcano: Insights from Phenocryst Zoning. Journal of Petrology, v. 47, p. 2303-2334. https://doi.org/10.1093/petrology/egl045
Kesler, S.E., Reich, M. and Jean, M., 2007. Geochemistry of fluid inclusion brines from Earths oldest Mississippi Valley-type (MVT) deposits. Chemical Geology, v. 237(3-4), p. 234-248. https://doi.org/10.1016/j.chemgeo.2006.11.001
Mehvari, R., Shamsipour Dehkordi, R., Bagheri, H., Noghreyan, M. and Mackizadeh, M.A., 2010. Mineralogical and fluids inclusion studies in the Kalchueh copper-gold deposit, East of Isfahan. Economic Geology, v. 1, p. 47-55 (In Persian). https://doi.org/10.22067/econg.v1i1.3680
Moncada, D., Mutchler, S., Nieto, A., Reynolds, T.J., Rimsltidt, J.D. and Bodnar, R.J., 2012. Mineral textures and fluid inclusions petrography of the epithermal Ag-Au deposits at Guanajuato, Mexico: Application to exploration. Journal of Geochemical Exploration, v. 114, p. 20-35. https://doi.org/10.1016/j.gexplo.2011.12.001
Muntean, J.L., Kesler, S.E., Russell, N. and Polanco, J., 1990. Evolution of the Monte Negro acid sulfate Au–Ag deposit, Pueblo Viejo, Dominican Republic–important factors in grade development. Economic Geology, v. 85, p. 1738-1758.
Nielsen, R.L., Ustunisik, G., Lange, A.E., Tepley III, F.J. and Kent, A.J.R., 2020. Trace element and isotopic characteristics of plagioclase megacrysts in plagioclase ultraphyric basalts (PUB). Geochemistry, Geophysics, Geosystems, v. 21, p. 8638. https://doi.org/10.1029/2019GC008638
Nouri, N., Azizi, H., Stern, R., Asahara, Y., Khodaparaslt, S., Madanipour, S. and Yamamoto, K., 2018. Zircon U-Pb dating, geochemisltry and evolution of the Late Eocene Saveh magmatic complex, central Iran: Partial melts of sub-continental lithospheric mantle and magmatic differentiation. Lithos, v. 314-315, p. 274-292.
Pirajno, F., 2009. Hydrothermal processes and mineral systems. Springer, Berlin, 1250 p. http://dx.doi.org/10.1007/978-1-4020-8613-7
Plechov, P.Y. and Tsai, A.E., Shcherbakov, V.D. and Dirksen, O.V., 2008. Opacitization conditions of hornblende in Bezymyannyi volcano andesites. Petrology, v. 16, p. 19-35. https://doi.org/10.1134/S0869591108010025
Rajabpour, Sh., Behzadi, M., Jiang, Sh.Y., Rasa, I., Lehmann, B. and Ma, Y., 2017. Sulfide chemistry and sulfur isotope characteristics of the Cenozoic volcanic-hosted Kuh-Pang copper deposit, Saveh county, northwestern central Iran. Ore Geology Reviews, v. 86, p. 563-583. http://dx.doi.org/10.1016/j.oregeorev.2017.03.001
Rajabpour, Sh., Jiang, S.Y., Lehmann, B., Abedini, A. and Gregory, D.D., 2018. Fluid inclusion and O-H–C isotopic, 9 consltraints on the origin and evolution of ore-forming fluids of the Cenozoic volcanic-hoslted Kuh-Pang copper deposit, Central Iran. Ore Geology Reviews, v. 94, p. 277-289. http://dx.doi.org/10.1016/j.oregeorev.2018.02.003
Regard, V., Bellier, O., Thomas, J.C., Abbassi, M.R., Mercier, J., Shabanian, E. and Soleymani, S., 2004. Accommodation of Arabia-Eurasia convergence in the Zagros- Makran transfer zone, SE Iran: A transition between collision and subduction through a young deforming system. Tectonics, v. 23(4), 24 p. https://doi.org/10.1029/2003TC001599
Renjith, M.L., 2014. Micro-textures in plagioclase from 1994–1995 eruption, Barren Island Volcano: Evidence of dynamic magma plumbing system in the Andaman subduction zone. Geoscience Frontiers, v. 5, p. 113-126. https://doi.org/10.1016/j.gsf.2013.03.006
Richards, J.P. and Sholeh, A., 2016. The Tethyan tectonic history and Cu-Au metallogeny of Iran. Economic Geology, v. 19, p. 193-212.
Roedder, E., 1984. Inclusion sample selection, preparation, petrography and photography. In: Ribbi, P.H. (Ed), Fluid Inclusions. Mineralogical Society America, Washington, D.C, p. 149-180.
Shepherd, T.J., Rankin, A.H. and Alderton, D.H.M., 1985. A Practical Guide to Fluid Inclusion Studies. Blackie and Son, Glasgow, 239 p. https://doi.10.1180/minmag.1986.050.356.32
Shimizu, T., 2014. Reinterpretation of quartz textures in terms of hydrothermal fluid evolution at the Koryu au-ag deposit. Economic Geology, v. 109, p. 2051-2065. https://doi.org/10.2113/econgeo.109.7.2051
Simmons, S.F., White, N.C. and John, D.A., 2005. Geological characteristics of epithermal precious and base metal deposits, In: Hedenquist, J.W., Thompson, J.F.H., Goldfarb, J.R., Richards, J.P. (Eds.), Economic Geology, v. 100, p. 485-522.
Tale Fazel, A., Mehrabi, B., Khakzad, A. and Kianpour, R., 2011. Stages and Mineralization conditions of Dardvey iron skarn based on mineralogy and fluid inclusion Evidences, Sangan area (Khorasan Razavi). Scientific Quarterly Journal of Geosciences, v. 21(82), p. 139-150 (In Persian).
Viccaro, M., Giacomoni, P.P., Ferlito, C. and Cristofolini, R., 2010. Dynamics of magma supply at Mt. Etna volcano (Southern Italy) as revealed by textural and compositional features of plagioclase phenocrysts. Lithos, v. 116, p. 77-91. https://doi.org/10.1016/j.lithos.2009.12.012
Viccaro, M., Giuffrida, M., Nicotra, E. and Ozerov, A.Y., 2012. Magma storage, ascent and recharge history prior to the 1991 eruption at Avachinsky Volcano, Kamchatka, Russia: Inferences on the plumbing system geometry. Lithos, v. 140-141, p. 11-24. https://doi.org/10.1016/j.lithos.2012.01.019
Wall, V.L., Clemens, J.D. and Clarke, D.B., 1987. Models for granitoid evolution and source composition. Geology. v. 6, p. 731-749.
Wang, L., Qin, K.Z., Song, G.X. and Li, G.M., 2019. A review of intermediate sulfidation epithermal deposits and subclassification. Ore Geology Reviews, v. 107, p. 434-456. https://doi.org/10.1016/j.oregeorev.2019.02.023
Waters, L.E. and Lange, R.A., 2015. An updated calibration of the plagioclase-liquid hygrometer-thermometer applicable to basalts through rhyolites. American Mineralogist, v. 100, p. 2172-2184.
Whitney, D.L. and Evans, W.E., 2010. Abbreviations for names of rock-forming minerals. American mineralogist, v. 95(1), p. 185-187. http://dx.doi.org/10.2138/am.2010.3371
Wilkinson, J.J., 2001. Fluid inclusion in hydrothermal ore deposits. Lithos, v. 55(1-4), p. 229-272. https://doi.org/10.1016/S0024-4937(00)00047-5
Williams-Jones, A.E., Schrijver, K., Doig, R. and Sangster, D.F., 1992. A model for epigenetic Ba-Pb-Zn mineralization in the Appalachian Trust Belt Quebec: Evidence from fluid inclusions and isotopes. Economic Geology, v. 87(1), p. 154-174. https://doi.org/10.2113/gsecongeo.87.1.154
Yermacov, N.P., 1965. Research on the nature of mineral-forming solutions with special reference to data from fluid inclusions, Pergamon Press, Oxford, 743 p.
Yilmaz, H., Oyman, T., Arehart, G.B., Colakoglu, A.R. and Billor, Z., 2007. Low sulfidation type Au-Ag mineralization at Bergama, Izmir, Turkey. Ore Geology Reviews, v. 32, p. 81-124. https://doi.org/10.1016/j.oregeorev.2006.10.007
Yousefi, S. and Alipour-asll, M., 2019. Vein-type copper mineralization in the Zarandieh area based on mineralogy, geochemistry and fluid inclusions studies, Saveh, Markazi province, Scientific Quarterly Journal, Geosciences, v. 28(111), p. 203-124. https://doi.org/10.22071/gsj.2018.82635.1090
Yushin, A. and Romanko, E., 1981. Isotope-geochemical characterisltics of mineral deposits of Anarak area (Cental 15 Iran). V/O Technoexport, Moscow. v. 16, 78 p
Zamanian, H., Dolatshahi, S., Yang, X., Karimzadeh, S.A.M. and Meshkani, S.A., 2021, Geochemical, fluid inclusion and O-H-S isotope consltraints on the origin of the Rangraz copper deposit, Central Iran. Ore Geology Reviews, v. 128, p. 103877. https://doi.org/10.1016/j.oregeorev.2020.103877.
 
 

Files

Share

How to cite

Statistics