عنوان مقاله [English]
Arabshah gold deposit formed through hydrothermal activity with an age of ~11 Ma (based on zircon U-Pb dating by LA-ICP-MS), in northwestern Iran. This hydrothermal activity is a part of the Urumieh-Dokhtar magmatic arc (UDMA), leading to mineralization in this area, similar to Zarshouran, Aghdarreh and Sarigunay gold deposits. Host rocks are a series of lower Paleozoic sedimentary sequences, cut by calc-alkaline to alkaline (high potassium) dacitic domes. Gold mineralization is mainly observed as vein-veinlets, open space filling, disseminated and brecciation in the deposit. The mineralization in terms of hydrothermal alteration (decalcification, minor argillic, sulfidization, dolomitization and silicification) and mineralization development process is associated with brecciation and deposition of base metal sulfides, iron, arsenic and antimony, similar to deposits associated with geothermal systems (low sulfidation epithermal) in volcanic arcs, but the host rock here is sedimentary. Sulfide minerals in the ore include pyrite, arsenopyrite, orpiment and realgar, stibnite, galena, sphalerite and minor amounts of chalcopyrite. Gold mineralization occurred in the form of released grains of oxidized pyrite, the tiny (invisible) in the sulfide phases such as arsenian pyrite for solid solution. The Arabshah deposit shows characteristic alteration assemblages and ore minerals (As, Sb, Hg, base metals) of epithermal low sulfidation deposits. It has been formed in relation to the mid-upper Miocene, high-level magmatic-hydrothermal activity within an extensional regime at the last stages of the UDMA activity in northwestern Iran.
Alavi, M., Hajian, J., Amidi, M. and Bolourchi, H., 1982- Geology of Takab-Saein-Qaleh, 1:250000, Report No. 50, Geological Survey of Iran.
Asadi, H. H., Voncken, J. H. L., Kanel, R. A. and Hale, M., 2000- Petrography, mineralogy and geochemistry of the Zarshuran Carlin-like gold deposit, northwest Iran. Mineralium Deposita 35: 656-671.
Baker, J., Peate, D., Waight, T. and Meyzen, C., 2004- Pb isotopic analysis of standards and samples using a Pb-207-Pb-204 double spike and thallium to correct for mass bias with a double-focusing MC-ICP-MS. Chemical Geology 211: 275-303.
Black, L. P. and Gulson, B. L., 1978- The age of the Mud Tank Carbonatite, Strangways Range, Northern Territory. Journal of Australian Geology and Geophysics 3: 227-232.
Black, L. P., Kamo, S. L., Allen, C. M., Davis, D. W., Aleninikoff, J. N., Valley, J. W., Mundil, R., Campbell, I. H., Korsch, R. J., Williams, I. S. and Foudoulis, C., 2004- Improved 206Pb/238U microprobe geochronology by the monitoring of a trace-element related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS, and oxygen isotope documentation for a series of zircon standards. Chemical Geology 205: 115-140.
Black, L. P., Kamos, L., Allen, C. M., Aleinikoff, J. N., Davis, D. W., Korsch, R. J. and Foudoulis, C., 2003- TEMORA 1: A new zircon standard for Phanerozoic U-Pb geochronology. Chemical Geology 200: 155-170.
Castillo, P. R., 2006- An overview of adakite petrogenesis. Chinese Science Bulletin 51: 257-268.
Daliran, F., 2008- The carbonate rock-hosted epithermal gold deposit of Agdarreh, Takab geothermal field, NW Iran: Hydrothermal alteration and mineralization. Mineralium Deposita 43: 383-404.
Frey, F. A., Chappell, B. W. and Roy, S. D., 1978- Fractionation of rare-earth elements in the Tuolumne intrusive series, Sierra Nevada batholith, California. Geology 6: 239-242.
Hanson, G. N., 1980- Rare earth elements in petrogenetic studies of igneous systems. Annual Review of Earth andPlanetary Sciences
Heidari, S. M., Daliran, F., Paquette, J. L. and Gasquet, D., 2014- Geology, timing, and genesis of the high sulfidation Au (-Cu) deposit of Touzlar, NW Iran. Ore Geology Reviews 65: 460-486.
Irvine, T. N. and Baragar, W. R. A., 1971- A guide to the chemical classification of the common volcanic rocks. Canadian Journal of Earth Sciences 8: 523-548.
Jackson, S. E., Pearson, N. J., Griffin, W. L. and Belousova, E. A., 2004- The application of laser ablation-inductively coupled plasma-mass spectrometry to in situ U-Pb zircon geochronology. Chemical Geology, 211: 47-69.
Kosler, J., 2001- Laser-ablation ICPMS study of metamorphic minerals and processes. In: Sylvester, P. J. (ed) Laser-ablation-ICPMS in the earth sciences; principles and applications, Mineralogical Association of Canada Short Course Handbook 29: 185-202.
Lang, J. R. and Titley, S. R., 1998- Isotopic and geochemical characteristics of Laramide magmatic systems in Arizona and implications for the genesis of porphyry copper deposits. Economic Geology 93: 138-170.
Le Bas, M. J., Le Maitre, R. W., Streckeisen, A. and Zanettin, B., 1986- A chemical classification of volcanic rocks based on total alkali-silica content. Journal of Petrology 27: 745-750.
Ludwig, K. R., 1998- Isoplot: A plotting and regression program for radiogenic isotope data, version 3.00.
McDonough, W. F. and Sun, S. S., 1995- The composition of the Earth. Chemical Geology 120: 223-253.
Meffre, S., Large, R. R., Scott, R., Woodhead, J., Chang, Z., Gilbert, S. E., Danyushevsky, L. V., Maslennikov, V. and Hergt, J. M., 2008- Age and pyrite Pb-isotopic composition of the giant Sukhoi Log sediment-hosted gold deposit, Russia. Geochimica et Cosmochimica Acta 72: 2377-2391.
Mehrabi, B., Yardley, B. W. D. and Cann, J. R., 1999- Sediment-hosted disseminated gold mineralization at Zarshuran, north-west Iran. Mineralium Deposita 34: 673-696.
Morrison, G. W., 1980- Characteristics and tectonic setting of the shoshonite rock association. Lithos 13, 97-108.
Muller, D. and Groves, D. I., 1997- Potassic Igneous Rocks and Associated Gold-Copper Mineralization. 3rd ed., Springer, Berlin, 252 p.
Paton, C., Woodhead, J. D., Hellstrom, J. C., Hergt, J. M., Greig, A. and Maas, R., 2010- Improved laser ablation U-Pb zircon geochronology through robust down-hole fractionation correction. Geochemistry, Geophysics, Geosystems 11: 1525-2027.
Pearce, J. A., Harris, N. B. W. and Tindle, A. G., 1984- Trace-element discrimination diagrams for the tectonic interpretation of granitic-rocks. Journal of Petrology 25: 956-983.
Peccerillo, A. and Taylor, S. R., 1976- Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, northern Turkey. Contributions to Mineralogy and Petrology 58: 63-81.
Pirajno, F., 2009- Hydrothermal Processes and Mineral Systems. Springer, Berlin, 1250 p.
Richards, J. P., Spell, T., Rameh, E., Razique, A. and Fletcher, T., 2012- High Sr/Y magmas reflect arc maturity, high magmatic water content, and porphyry Cu ± Mo ± Au potential: Examples from the Tethyan arcs of central and eastern Iran and western Pakistan. Economic Geology 107: 295-332.
Richards, J., Wilkinson, D. and Ulrich, T., 2006- Geology of the Sari Gunay epithermal gold deposit, northwest Iran. Economic Geology 101: 1455-1496.
Wiedenbeck, M., Alle, P., Corfu, F., Griffin, W. L., Meier, M., Oberli, F., Von Quadt, A., Roddick, J. C. and Spiegel, W., 1995- Three natural zircon standards for U-Th-Pb, Lu-Hf, trace-element and REE analyses: Geostandards and Geoanalytical Research 19: 1-23.