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Hassan Abad Au-Sb prospect area is located in north of Khorasan Razavi Province about 45 km souht of Neyshabour. Volcanic rocks (rhyolite, rhyodacite, trachyandesite and andesitic-basalt) and sub-volcanic intrusive (Eocene-Oligocene) such as biotite diorite porphyry, biotite hornblende diorite porphyry, hornblende monzonite porphyry, biotite micogranite, micogranodiorite, and granodiorite were identified in the study area. Alteration zones which are mapped in the surface and sub-surface are: 1- argillic zone, 2- sericite-quartz-pyrite zone, 3- carbonate zone, 4- propylitic zone, and 5- silicified zone. Vein type mineralization is dominate with minor veinlets, breccia and disseminated. Eight exploratory holes were drilled in the exploration area. In this research, IP/RS pseudo section in profiles 0, 150W and 300W were interpreted using drilled core observation and studies. Profile 0 has a chargeability anomaly greater than 25 milli second in the south eastern part of Gold- Antimony vein which is smaller than 150W and is at greater depth. In profile 150W, chargeability anomaly reach to greater than 50 millisecond with northeast-southwest trend and is highest in the center of the vein and is dissected by a fault. Chargeability anomaly extends towards northwest of the main Gold-Antimony vein and is observed as three small discontinuous anomaly in profile 300W. High chargeability anomaly and its extension in all three pseudo sections confirm the presence of conductive sulfide and correlates with the results of observed mineralization on the drilled cores. Increase in electrical resistivity in profile 150W is related to subvolcanic intrusive body of quartz monzodiorite porphyry which is observed on drilled cores and appears to be younger than granite. Observed mylonite in drilled core and dissection of chargeability anomaly infer a fault which mylonite the quartz monzonite sub-volcanic body before the creation of mineralization. Detailed surface and sub-surface geological, alteration and mineralization studies correlate well with IP/RS anomalies and confirm them. Thus it can be predicted that in the north eastern portion of profile P150W where no mineralization is observed in the surface but it well extend at depth and two drill cores at 200 and 440 meter distance on the north are proposed.

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The Mafic complex of Mishow is exposed in the north-western part of Iran, in the East Azerbaidjan Province (SW of Marand). Two different types of mineralization, sulphides and oxides, occur in the intrusion complex. The sulphide ore bodies are mainly composed of pyrrhotite accompanied by chalcopyrite, pentlandite, sphalerite, pyrite and troilite. The oxides mineralization consists of ilmenite and rarely magnetite. Primary sulfides are replaced by pyrite and violarite during alteration states. Thermometry investigation, based on exsolution texture of chalcopyrite-sphalerite, suggest that sulfide zone probably formed at temperature higher than 400°C. The Co/Ni values of sulfides propose that they formed in a magmatic immiscible sulfide Ni-Fe-Cu system.

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The Mafic complex of Mishow is exposed in the north-western part of Iran, in the East Azerbaidjan Province (SW of Marand). Two different types of mineralization, sulphides and oxides, occur in the intrusion complex. The sulphide ore bodies are mainly composed of pyrrhotite accompanied by chalcopyrite, pentlandite, sphalerite, pyrite and troilite. The oxides mineralization consists of ilmenite and rarely magnetite. Primary sulfides are replaced by pyrite and violarite during alteration states. Thermometry investigation, based on exsolution texture of chalcopyrite-sphalerite, suggest that sulfide zone probably formed at temperature higher than 400°C. The Co/Ni values of sulfides propose that they formed in a magmatic immiscible sulfide Ni-Fe-Cu system.

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Modeling based on equilibrium thermodynamic and physicochemical condition suggests that Bi-rich melts can efficiently scavenge Au from hydrothermal fluids, even if these fluids are highly undersaturated with respect to Au minerals. At this study the Kuh-e Dom prospecting area in northeastern of Ardestan city (northern part of Anarak metallogenic province) as the prominent sample of Iron Oxide Cu-Au (IOCG) hyrothermal deposit have been investigated by quartz-hematite-sulfide mineralization accompanied with Fe-Cu-Au assemblage. The fahlor-group sulfosalt minerals, Bi-minerals and trace metals (e.g., gold, bismuth and electrum) investigated due to achievement of chemical composition and genetic relation to Au mineralization. Au scavenging occurs efficiently by Bi-minerals such as bismuthinite (B_2.05S_2.9), emplectite (Cu_0.56Fe_0.03Bi_1.2S_2.16), and native bismuth (Cu_0.14Bi_0.86). Evidence shows release electron from reduced minerals (e.g., pyrrhotite) and consequently increase of fluid oxygen have been eventuated Bi³⁺ to Bi⁰ and precipitation of bismuth. Hence, with occurrence of magnetite as the stable buffer phase the release electron involves reduction Au⁺ to Au⁰ and adsorbed by bismuth minerals.    

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The gold-bearing prospect area at Gharehchay is located in about 2 km south of Tikmehdash, East-Azarbaidjan, NW Iran. The host rocks of the gold-bearing quartz veins/veinlets are principally Eocene andesites and upper Eocene-Oligocene felsic intrusive body (granite to alkali granite). Wall rocks alteration haloes developed around the veins/veinlets are mainly of silicic, phyllic, phyllic-argillic, and propylitic types. The sulfide and gold mineralization in the study area occurred as vein/veinlet, stockwork, and open-space filling. The hypogene opaque minerals are chiefly pyrite, chalcopyrite, and gold which were overprinted by supergene mineral assemblages like Fe-oxides/hydroxides (goethite, jarosite, and hematite), copper carbonates (malachite and azurite), and secondary copper sulfides (covellite and chalcocite). The quartz crystals within the veins/veinlets show typically brecciated, crustification, comb, and vuggy textures. Based upon the microthermometric analyses, the Th and salinity values of the studied fluid inclusions vary from 200ºC to 340ºC and from 6.2 to 11.7 wt% NaCl eq., respectively. The fluid inclusion data along with the presence of hydrothermal breccias in the quartz veins/veinlets show that both boiling and simple cooling were the important factors in precipitation of sulfide and gold minerals at Gharehchay. Both sulfide and chloride complexing ligands played significant role in transporting of the ore metals. According to the data obtained from fluid inclusions, mineralogy, and textures of the ore and gangue minerals in the quartz veins/veinlets, the sulfide and gold mineralization at Gharehchay can be reckoned as low-sulfidation epithermaltype.