جستجوی مقالات مرتبط با کلیدواژه « میانبار سیال » در نشریات گروه « زمین شناسی »

The Niaz Cu prospect is located 25 km west of Meshkinshahr, east of the Qaradagh metallogenic zone. The intrusion Oligo-Miocene magmatic bodies into the Paleocene-Eocene rock units has led to alteration and mineralization. The rock units of this area include batholiths Ι and ΙΙ (Khanbaz granodiorite and Khankandi granodiorite), Niaz quartz-monzonite/ quartz-monzodiorite and ore-bearing rhyodacite breccia.

In this research, the geological features, alteration, mineralization and physicochemical conditions of mineralizing fluids have been studied. In this regard, sampling from altered, mineralized zones and drilling cores were carried out and 23 samples were analyzed by XRF and 18 samples by ICP-OES methods and microthermometric measurements were performed on 8 doubly-polished thin sections.

The intrusive units have high-K calc-alkaline to shoshonitic nature, and the geochemical characteristics of their trace elements indicate similarities with subduction-related magmas. The negative anomaly of Ti and Nb in these rocks can be due to the magmatism related to the subduction processes, as well as the stability of the phases containing these elements during partial melting or their separation during the differentiation process. The enrichment of Pb, La, K, U, and Th elements and the depletion of Sr, Ti, and Nb can be attributed to crustal contamination. Hypogene alterations at Niaz include potassic, phyllic, propylitic and intermediate argillic types. Mineralization has occurred during early, middle, and late stages. Based on the mineralogy and paragenetic sequence, at least five types of veins/veinlets can be distinguished in Niaz deposit. Group A veinlets contain quartz+pyrite+chalcopyrite+magnetite, group B veins are also present in the potassic and phyllic alteration zones, veinlets of group C are mainly formed in the middle stage of mineralization, group D veins are mostly observed in the phyllic alteration zone, which are formed in the middle and later stages of hydrothermal activities and group E veins are almost devoid of sulfide minerals and mainly contain bright-color minerals (quartz and/or calcite)±tourmaline and are mostly present in the propylitic alteration zone. Studies on fluid inclusions (FIs) within the quartz veinlets showed that there are four types of FIs at room temperature, (1) mono-phase vapor, (2) liquid-rich 2-phase, (3) vapor-rich 2-phase, and (4) multi-phase solid containing daughter solid phases. The ranges of FIs are about 280-360°C in the potassic, 280-360°C and 280-300°C in phyllic and 170-330°C in propylitic alteration zones.

The petrology and petrogenesis of magmatic host rocks, mineralogy, hydrothermal alteration in the Niaz area testify to a porphyry-type Cu mineralization. The main sulfide mineralization includes vein-type pyrite, molybdenite, chalcopyrite, sphalerite and galena. Fluid inclusion microthermometry results show a Th range of 170-360 °C and salinity values of 0.2-60 wt%NaCl equiv., corresponding to the ranges of porphyry Cu deposits. Boiling and simple colling of ore-bearing fluids were the main processes for ore precipitation.

Baba-Ali and Galali deposits are located in 30 and 60 km northwest of Hamedan in northwest part of the Sanandaj-Sirjan zone. The host rocks of these deposits are metavolcano-sedimentary successions of Songhor series in Permo-Triassic age. Stratigraphic position of ore horizons, geometry of orebodies, ore structures and textures in different scales and paragenetic sequence of minerals all show close genetic relation between iron ore and the metavolcanosedimentary and subvolcanic rocks. The host rocks in the area are felsic to intermediate metavolcanic rocks, more than lava and rhyolitic tuffs with interculations of carbonate and metatuff-sandstones. Field observations and petrography show that emplacement of plutons and subvolcanic rock units with composition of gabbrodiorite, quartzmonzodiorite, granodiorite, syenite, syenogranite and granite in these successions caused deformation and metamorphism of ore and country rocks.

In this research, 56 polished sections were prepared from iron ore of Baba Ali and Galali deposits, and the mineralogical characteristics and texture of the mineral in relation to gangue minerals were carefully studied using a reflected light mineralogical microscope. In order to determine the origin of ore-rich fluid, studies of fluid inclusions have been carried out on 6 double polished sections in the research laboratory of Tarbiat Modares University. Also, 29 samples of separated phases of sulphide, oxide-silicate and carbonate minerals from ore and gangue minerals of Baba Ali and Galali iron deposits have been analyzed for stable isotope analysis in Queen's University Isotope Research Laboratory in Canada.

From field evidences, fluid inclusions data, as well as stable isotope analysis in this study, emplacement of plutons and subvolcanic rock units with composition of gabbrodiorite, quartzmonzodiorite, granodiorite, syenite, syenogranite and granite in these successions caused deformation and metamorphism of ore and country rocks. Fluid inclusion studies within the quartz crystals indicate that main salinity varies between 12±5 and 9±5 wt.% NaCl equivalent in Baba-Ali and Galali deposits respectively. Homogenization temperature for Baba-Ali and Galali deposits are 226±5 and 220±5 oC respectively. Occurrence of dynamothermal regional metamorphism in these deposits typically involves a lengthy period of time, during which there was a tendency toward isotopic homogenization specifically in O (3 to 10.5 ‰) and H (-10 to -35 ‰) stable isotopes and show the role of metamorphic waters in mineralization process. Measurement of δ34S (CDT) in first generation of pyrite is higher than another one, so these data confirm the volcano-sedimentary origin of primary iron mineralization.

Field observations, structure and texture, host rock, intercualation, geochemistry, alterations, studies of fluid inclusion and stable isotopes in Baba Ali and Galali deposits show that these deposits are volcanic-sedimentary iron deposits. Since most of these mineralizations are located in metamorphosed volcanic-sedimentary units, these rock groups are of great importance in terms of iron exploration. Investigating these stone units in the region and generalizing the evidence obtained from them to similar areas in Sanandaj-Sirjan zone can lead to the identification of this type of iron deposits.

Hosein-Abad Jurassic slate and phyllite-hosted Zn-Pb ore deposit is located in the northern Irankuh- Ahangaran metallogenic belt. Structural investigations document the study area was structurally controlled by a northward-steeply dipping Hossein-Abad reverse fault zone with thickness of 20 meters where it cuts through the Jurassic-Cretaceous units and effected mineralization. Main mineralization of sphalerite, galena and subordinate pyrite, and minor chalcopyrite have been occurred in form of brecciation, vein-veinlet, and replacement textures as epigenetic mineralization. The main alteration minerals are quartz, siderite, calcite, dolomite, sericite, and chlorite. Geochemical investigations decipher active continental margin and anomalously enrichment of Pb and Zn for the metamorphosed Jurassic host rock. Pb, Zn, S, Cu, Ag, and As elements have the genetic relationship with the deposit. The Zn/Cd ratio in sphalerite range from 37 to 581. The Pb-Pb isotope modeling age analysis of galena suggests the remobilization of Pb from Upper Triassic-Lower Jurassic strata as most possible source. The overall ranges of homogenization temperatures and salinities of fluid inclusions range from 100 to 305 ℃ and from 10.5 to 13.3 wt. % NaCl, respectively. The Hossein-Abad reverse fault caused fault related E-W trending hanging wall anticline and foot wall-syncline, respectively. The drag folds are faded out outward of E-W trending reverse fault zone and turned to its NW-SE origin structural trend. Furthermore, the breccia- type mineralization is dominantly occurred and distributed along the Hossein-Abad reverse fault zone and clearly fade out far from fault zone.

Nineh Pb-Zn deposit is located in the east of the Markazi province, in the Middle to Upper Jurassic rock units of the Malayer-Esfahan  metallogenic belt. Stratified and epigenetic mineralization, in the form of veins, replacement and open spaces filling, including the main minerals of galena, sphalerite and barite accompanied by dolomite and siliceous alterations are observed. The microthermometry results of fluid inclusions in calcite and barite, display mean homogenization temperature of about 168.6°C and 127.3°C, and a mean salinity of 5.7 and 13.9 wt. % NaCl equiv., respectively, which indicates slight difference in their formation conditions. The homogenization temperature versus salinity diagram suggests a basinal brine fluid mineralizer and mixing and cooling processes for the mineralization. The values of δ34S in galena and sphalerite (7.5‰ to 21.5‰) of this deposit are similar to the values of δ34S in the upper Mississippi deposits, indicating the supply of sulfur during the process of thermochemical reduction of sulfate. The values of δ18OSMOW (-9.2 to -11.2‰) and δ13CPDB (0.1 to 0.5‰) of the calcite veins indicate a multi-origin of oxygen, and the origin of carbon from dissolved and remobilized marine carbonates. According to the evidence obtained during this study, the Nineh deposit can be classified as the Mississippi Valley type deposits, which was formed during the orogeny processes and the movement of basinal brine  fluids.

The Godar Sorkh area is located in the central part of the Sanandaj-Sirjan zone, 20 km southwest of the Muteh region. Gold mineralization at Godar Sorkh occurs in quartz-sulfide veins that hosted in metasedimentary rocks. Veins of mineralization typically formed along normal faults.  Rock sequences are affected by several deformation phase, gold mineralization occurs in ductile to ductile-brittle shear zones and had been under poly-phase metamorphism.  The main alterations are Sulfidation, carbonization, silicification, chloritization, and sericitization. Ore-mineral assemblages include pyrite and chalcopyrite, arsenopyrite, sphalerite, galena, and Fe-oxide.  Mean homogenization temperature in gold-bearing quartz range between 275oC and 300oC. Fluid inclusions in quartz veins are dominated by CO2-H2O-NaCl fluid. Salinity ranges from 9 to 17 wt. % NaCl equivalent. Corresponding to a depth of <2 km, Godar Sorkh deposit is formed in epizonal environment.  Measured δ18O values for the gold-bearing quartz range between 12.7 to 14.3 permil, estimated δ18Ofluid values range from +6.4 to +7.3 permil, δ34S values range from –16 to +5 permil, and estimated δ34Sfluid values range from +4.2 to -17.3 permil.  Fluid inclusion and stable isotope studies on ore-bearing quartz-sulfide veins indicating the major role of metamorphic fluids. Gold derived from metasedimentary rocks. Gold mineralization in the Godar sorkh deposit classified as an orogenic gold deposit.

The Madanjoo prospect is one of the eastern anomalies in the Sangan mining district. This area is located in the eastern part of the Cenozoic Alborz volcanic-plutonic arc. The geology of the area includes Jurassic shaly sandstone, lime mudstone, and sandstone, Upper Cretaceous limestone and dolomitic limestone, and Upper Eocene tuff and lava flow sequences, Middle Eocene skarn rocks, and Quaternary sediments. The most important occurrence in the Madanjoo area is the penetration of ferrous fluids into terrigenous and carbonate formations, skarnization, and iron mineralization, which is characterized by the presence of magnetite and calcsilicates minerals. based on type and frequency of calcsilicates, The skarn zones include olivine-pyroxene-garnet skarn, garnet-pyroxene skarn, garnet skarn, pyroxene-wollastonite-magnetite skarn, magnetite skarn, phlogopite skarn, tremolite-actinolite skarn, and epidote skarn. Iron mineralization occurred as massive, banded, vein-veinlets, breccia, and disseminated forms mostly in the Upper Cretaceous limestone and dolomite rocks and along NE-SW fault zone trend. Magnetite is the main ore mineral accompanied with pyrite, chalcopyrite, pyrrhotite, and secondary iron minerals. The composition of the Madanjoo garnet, pyroxene, and olivine are andradite-grossular (mostly andradite), diopside-hedenbergite (mostly diopside), and forsterite, respectively. Thermobarometry study based on pyroxene chemistry show that pyroxenes crystallized in temperature range of 458-689 °C, pressure of 2.21 kb, and depth range of 1-2.5 km. Three main paragenetic stages of skarn formation and ore deposition were recognized in the Madanjoo deposit: (1) a prograde stage developed with prograde garnet and pyroxene forming at 330° to 410 °C with a fluid salinity between 33 to 58 wt.% NaCl equivalent, (2) a retrograde garnet, tremolite- actinolite, and calcite which formed at 120° to 300 °C with fluid salinity of 16 to 49 wt.% NaCl equivalent, and (3) a post-ore stage with calcite and minor quartz veins that developed at 95° to 190 °C with salinity range of 2 to 15 wt.% NaCl equivalent. Possible iron ore formation mechanisms include: fluid mixing, boiling, and dilution with meteoric waters along with decreasing temperature. Finally, the Madanjoo iron mineralization is introduced as a magnesian exoskarn iron deposit.

The volcanic complex of North Khour  located in southern Khorasan province, 90 km northwest of Birjand in the Eastern of  Iran. The rocks under study are basaltic andesite, andesite and trachyandesite, latite, dacite to rhyodacite with tuff and breccia as pyroclastic rocks. The volcanic rocks are predominantly calc-alkaline nature with some tholeiitic affinity and porphyry texture. Iron mineralization developed as magnetite, hematite and small amount of goethite with magmatic origin, on the base of field observations. Bornite as the only and the primary Cu ore occurred as a small body. The presence of minor amounts of bornite and pyrite as the sulfide phases as well as the absence of the other Cu primary sulfide ores in the area along with secondary Cu mineralization phases reflect a hydrothermal solution with high oxidation degree which has passed the latest magmatic differentiation and gave rise to form surface Cu ores as chalcocite in supergene zone. The thermobarometry of fluid inclusions studies from Ghar Kaftar and Hoze Sabz, yield temperature range of 178 -324 C for Cu mineralization. Therefore, it seems that Cu mineralization is related to epithermal to mesothermal conditions.

Hararan deposit is located 110 km northeast of Baft city, Kerman province. This area is located on the Urmia-Dokhtar belt. The predominant lithology in the area of ​​Hararan copper deposit includes a collection of volcanic and igneous rocks with shallow infiltration massifs. One of the important features of this region is the intense volcanic activity and the formation of the volume of potassic, argillic, proplitic and siliceous alterations due to the influence of igneous masses into volcanic rocks, which is related to the Eocene. In the host rock of Hararan deposit, more mineralization can be detected in the form of veins, veinlets, under the control of open spaces of fractures and stockwork. The area has alleles of algal, potash, propolitic and silicification alteration. Mineralization in siliceous alteration zones may be associated with amounts of gold and the elements silver, arsenic, and antimony. Supergene processes are observed in potash and propylitic zones with outcrops of malachite, neocyte minerals and in argillic zone with jarocyte and goethite minerals. The data obtained from the study of quartz mineral fluid intermediates show that mineralization is formed in the temperature range of 110 to 410 ° C. The highest salinity rate was between 4 and 21% by weight equivalent of NaCl. Field evidence and microscopy of fluid intermediates in the quartz mineral of the Hararan deposit show that the ore-forming fluid is very similar to epitermal.

Varmazyar Pb–Zn (Ag) occurrence, 65 km north of Zanjan, is located in the Tarom–Hashtjin metallogenic belt (THMB). The THMB has been recognized as one of the most important epithermal metallogenic belts in Iran (Kouhestani et al., 2018b) that host numerous small- to medium-sized epithermal deposits (i.e., Gulojeh, Aqkand, Aliabad–Khanchy, Chodarchay, Khalyfehlou, Chargar, Zajkan, Marshoun, Abbasabad, Zehabad, and Shah Ali Beiglou). These epithermal deposits are temporally and spatially related to late Eocene granitoids (Mehrabi et al., 2016; Kouhestani et al., 2018b).Although the general geological characteristics of the region, where the Varmazyar occurrence is located, were determined (Faridi and Anvari, 2000), no detailed studies have been conducted on the mineralogy, geochemistry, and the ore-forming fluids characteristics of the Varmazyar occurrence. In this paper, we investigate the geology, mineralogy, geochemistry, fluid inclusions, and alteration styles of the Varmazyar occurrence to constrain its ore genesis. These results may have implication for the regional exploration of epithermal deposits in the THMB.

Detailed field work has been carried out at different scales in the Varmazyar area. A total of 70 samples were collected from various parts of ore veins and breccias, host tuff units and granitoid intrusion. The samples prepared for thin (n=15) and polished-thin (n=27) sections in the laboratory of University of Zanjan, Zanjan, Iran. Representative 7 samples from the mineralized veins and breccias, 1 sample from host intermediate tuff unit and 1 sample from barren and fresh granite intrusion, were analyzed for rare and rare earth elements using ICP–MS in the Zarazma Analytical Laboratories, Tehran, Iran.Fluid inclusion measurements have been conducted on 4 doubly polished thick (~150 μm) sections including crystalline quartz, and sphalerite from the second, and third stages of ore formation. Microthermometric measurements were performed using a Linkam THMSG-600 heating–freezing stage attached to a ZEISS microscope in the fluid inclusion laboratory of Iranian Mineral Processing Research Center, Tehran, Iran.

The geological units hosting the Varmazyar occurrence are mainly Eocene volcanic and volcaniclastic rocks that were intruded by late Eocene granitoids. The volcaniclastic rocks can be divided into two units as acidic (lithic tuff, lithic crystal tuff and crystal tuff) and intermediate (lithic crystal tuff, crystal tuff, and lithic tuff) units. They are metamorphosed to clinopyroxene hornfels facies near contact intrusions. The granodiorite intrusion is the main rock units in the Varmazyar area. It crops out mainly in the south, southwest and northeast of the Varmazyar occurrence. It ranges in composition from monzogranite to syenogranite and shows porphyritic and granular textures.Mineralization at Varmazyar occurs as epithermal base metal quartz-sulfide brecciated vein that occupy NS-trending faults in the Eocene acidic and intermediate tuff units.  The ore vein extends up to 300 m along, from several cm to 2–3 m wide, and generally dip steeply (65–80°) to the west. Wall-rock alterations developed at the Varmazyar occurrence include silicification, intermediate argillic, carbonate, and propylitic alteration; the first three are closely related to the Pb–Zn (Ag) mineralization. The alteration styles show a systematic zonation pattern, from the silica, via intermediate argillic, to propylitic alteration. Four stages of mineralization can be distinguished at Varmazyar. Stage 1 is represented by silicification of host rocks along with minor disseminated pyrite. This stage is a pre-ore stage and usually crosscut by later stages. Stage 2 is the main ore-stage at the Varmazyar occurrence. It is characterized by up to 5 cm wide quartz veins and breccias that contain variable amounts of disseminated galena, sphalerite, and minor pyrite. Clasts of this stage and associated wall-rock alteration have been recognized in the hydrothermal cements of stage 3 breccias. Stage 3 is marked by quartz-calcite-manganese oxides (psilomelane, pyrolusite, braunite) veins and breccia cements. It is usually crosscut previous mineralization stages and, in turn, is cut by stage 4 calcite veinlets. Stage 4 is a barren post-ore stage represented by < 1 mm wide calcite veinlets. This stage usually crosscuts previous ore stages. No sulfide minerals are recognized with stage 4. The ore minerals at Varmazyar formed as vein-veinlet and hydrothermal breccia cements, and show disseminated, vein-veinlet, brecciated, comb, crustiform, colloform, cockade, bladed, plumose, and vug infill textures. Galena, sphalerite, pyrite, psilomelane, and pyrolusite are the main ore minerals; smithsonite, cerussite, goethite, secondary pyrolusite, and braunite are supergene minerals. Quartz, calcite, and sericite are present in the gangue minerals. Comparison of Chondrite–normalized rare elements and REE patterns of host intermediate tuffs, barren and fresh granite intrusion, and the mineralized samples at Varmazyar indicate that mineralization is probably genetically related with granite intrusions. In this case, leaching of some elements from the host tuff units may have involved in mineralization. Ore-forming fluids associated with the quartz-sulfide veins are represented by two-phase aqueous inclusions and by H2O–NaCl fluids with moderate-temperature (135–249 °C) and low-salinity (0.2–6.4 wt.% NaCl equiv.). Fluid inclusion data indicates that fluid boiling and mixing were important processes in the evolution of the ore-forming fluids at Varmazyar. Our data suggest that Varmazyar is an example of intermediate-sulfidation type of epithermal base metal mineralization.

The Sarikhanloo area is located within the Qaradagh metallogenic zone in northwest Meshgin Shahr. Igneous rocks cropped out in this area include successions of Paleocene-Eocene pyroclastic rocks (tuff and andesitic-dacitic lavas with intercalations of ignimbrite) and basaltic andesite lava flows. Igneous rocks show high-K calc-alkaline to shoshonitic nature and are mainly metaluminous, formed in a post-collisional uplift tectonic setting. Hydrothermal activities in this area brought about formation of vast silicic veins and caps, along with silicic, propylitic, phyllic (non-pervasive) and intermediate argillic alterations around the veins, as well as intermediate to advanced argillic alteration halos at the margins of silicic caps. Ore minerals in the silicic veins includes pyrite, arsenopyrite and Fe-oxides, accompanied by minor malachite, formed during four mineralization stages. Fluid inclusion studies indicate that the homogenization temperature of fluid inclusions ranges from 175 to 355 °C, considering the low pressure of fluid inclusions (≤ 0-40 bars), can signify the fluid temperature at the time of entrapment. The estimated salinity values are between 0.2 and 3 wt% NaCleq.

Bagh Khoshk deposit is located 35 km northeast of Sirjan in the southern Urmia- Dokhtar magmatic belt (Kerman metallogenic area). The magmatic activities and copper mineralization in this belt are attributed to the Eocene-Oligocene, middle-late Oligocene, and middle-late Miocene. Meanwhile, fertile porphyry copper deposits are genetically associated with middle-late Miocene granitoids (adakitic intrusive rocks). In Kerman metallogenic area, intrusive rocks are divided into productive with Miocene age (Kuh-Panj type) and semi-productive to barren groups with Eocene-Oligocene age (Jebal Barez type). Bagh Khoshk copper deposit has not been studied in terms of mineralization and genesis. In addition, it is not clear whether the Bagh Khoshk granitoid intrusion is a productive or semi-productive to barren magmatic system in the Kerman region. In this research, Bagh Khoshk deposit has been studied from the perspective of lithology, alteration, geochemistry, mineralization and fluid inclusion and by determining the geochemical nature of Bagh Khoshk granitoids, the origin of copper mineralization has been investigated.

In this research, the number of 21 samples from the outcrops and 24 samples of drilling cores have been selected for petrographic and mineralogical studies. 13 unaltered to less altered rock samples were taken from the outcrops and drilling cores for petrological studies and analyzed using XRF and ICP-OES/MS methods for major and trace elements. Ore geochemistry study has been done on 491 rock samples from drilling cores. To study the fluid inclusion, 4 mineralized samples were selected from the potassic and phyllic alteration zones and after preparation of double polished sections, micro-thermometry studies were done on quartz crystals.

The Eocene andesite to basaltic andesite lava flows and tuffs are the most widespread rock units in the Bagh Khoshk area. Late Miocene hypabyssal porphyry granodiorite and diorite stocks are intruded into the volcanic rocks. The alterations include potassic, prophylitic, phyllic, and argillic zones from the inside out. This deposit includes sulfide minerals (pyrite, chalcopyrite, bornite, molybdenite, chalcocite, and covellite), iron oxides (magnetite, olygiste, hematite, and goethite) and malachite which are mostly observed as disseminated and vein-veinlet forms in the potassic and phyllic zones. Copper is the major element, which has a positive correlation with molybdenum. Fluid inclusions in quartz crystals include LV, VL, and LVH types. The homogenization temperature of the LV, VL, and LVH fluid inclusions ranging from 180 to 289, 331 to 565, and 207 to 276 ⁰C. Their salinity varies from 0.35 to 10.24, 0.88 to 11.22, 33.55 to 42.66 wt.% NaCl eq., respectively. The Bagh Khoshk magmatic system in the Urmia-Dokhtar belt, was formed by partial melting of mantle source and thickening of lower crust, where the share of lower crust has been dominant. Finally, the Bagh Khoshk mineralization is a porphyry copper deposit, which is associated with adakitic and productive late Miocene magmas.

The late Miocene granodiorite intrusions host copper mineralization in the Bagh Khoshk area. These intrusions have the geochemical properties of adakitic magmas and are located in a normal continental arc environment. Enrichment in LREE, high Sr/Y and La/Yb ratios, enrichment in LILE and Sr, and depletion in HFSE are prominent geochemical features of Bagh Khoshk granitoids. Chalcopyrite is the most important copper-bearing mineral that is found as disseminated and vein- veinlets forms in the potassic and phyllic alteration zones. Based on fluid inclusion studies, the normal cooling of magmatic fluids and their mixing with meteoric waters has been one of the most important factors of metal deposition and the average depth of fluid inclusions entrapment and placement of the Bagh Khoshk porphyry stock is estimated at about 1200 m. The Bagh Khoshk magmatic system consists of partial melting of a mantle source with garnet amphibolite composition and a thickened lower crust, in which the share of lower crust has been dominant. The rapid rise of productive adakitic magma has led to the formation of economic copper deposit in this area.

The Gheshlaghe mil deposit is located in the Urumieh-Dokhtar magmatic belt. Vein- type mineralization is concordance within the rhyodacitic and rhyolite meta-tuff with Eocene age. Alteration zones of sericite, silica, argillic and iron oxides are observed in the investigated area. Primary sulfide minerals of pyrite, fine-grained chalcopyrite and Oxidized specularite and Secondary minerals goethite, limonite, malachite and quartz in Microscopic and field studies have been identified. Based on X-ray diffraction analysis studies minerals such as chlorite, illite, kaolinite, hematite, quartz, mica group and calcite have been observed in the bearing gold veins. According litho-geochemical studies, the gold element has a positive correlation with iron, molybdenum, nickel and lead. A number of 157 fluid inclusion studies in the Gheshlaghe Mil ore mineralization area has been showed mineralization temperature of 99 to 299 °C, rate of salinity ore deposit 1.81 and 12.30 equivalent to the Nacl weight percent. Using Raman laser studies (13 points), the presence of gaseous phases (CO2, N2, H2O) in the fluid inclusions have been demonstrated. Regarding to studies have been done in this area, the Gheshlaghe Mil ore mineralization can to know to a vein type- hydrothermal bearing gold-copper ore deposit.

Agh-Darreh copper deposit is located in Tarom area, about 25 km north of Abhar city. Main alterations identified in this region include silicic, argillic, and propylitic. Andesite and silica veins host sulfide mineralization. Chalcopyrite and pyrite are the main hypogene minerals accompanied by gold and silver in siliceous veins, with smaller amounts of galena. Malachite, azurite and goethite are the most important supergene minerals. The correlation between Pb and Zn is justified by Galena and the positive correlation between Cu and Fe is justified by the chalcopyrite and pyrite paragenesis. The relative enrichment of LILE and LREE with a depletion of HFSE and the presence of calc-alkaline volcanic rocks implies that the  primary magma generated in the subduction environment and was probably contaminated by continental crust. Based on micro-thermometry, two-phase fluid inclusions (L+V), mineralization have occurred at 140º to 270ºC from a fluid with salinity ranged approximately from 0.7 wt% up to 11 wt% NaCl through boiling, blending and cooling environments. Agh-Darreh deposit is characteristic of a potential vein-type epithermal and porphyry copper system in the lower parts of theTarom area.

The vein-type mineralization of the base (Zn, Pb, and Cu) and precious metals (Au) in the Qarah Changel area (northwest of Qazvin) is located in the southern part of the Tarom-Hashtjin metallogenic belt. Volcanic (trachy-andesite, rhyolite and dacite) and pyroclastic (tuff, tuffite and tuffaceous shale) (Eocene) rocks are the hosts of this mineralization. Distinctive alterations around mineralized veins include argillic, sericitic, propylitic and silicic. Ore mineralization has occurred in two forms, hypogene and supergene. Hypogene ore minerals include sphalerite, galena, chalcopyrite, pyrite, magnetite, gold, digenite, and bornite, which are associated with supergene mineralogical assemblages such as calcocite, covellite, cerussite, malachite, azurite, hematite, and goethite. Calcite and quartz are the associated gaugues of this mineralization. The texture of the ore consists of vein-veinlet, replacement, breccia, disseminated, bladed and open space filling. According to geochemical studies, volcanic host rocks are peralumine and have the nature of high- potassium clac-alkaline to shoshonitic. The enrichment of K, Ba and Cs in comparision to Ti, Nb and Zr, the LREEs enrichment relative to HREEs, and the occurrence of negative Nb anomaly indicate the formation of a magma generating volcanic rocks in the subduction zone. Studies of fluid inclusions in quartz mineral co-genetic with sulfide ore minerals showed that they are chiefly of L+V and having homogenization temperature in the range of 202 to 247 C°. The salinity of fluid iinclusions also ranges from 10 to 22 wt% NaCl eq. According to microthermometric data, boiling and cooling are the most important mechanisms in the development of mineralized veins. Evidence such as the coexistence of liquid and vapor-rich fluid inclusions, hydrothermal breccias, microcrystalline quartz and bladed calcite confirm the occurrence of the boiling phenomenon during the formation of mineralized veins. Combining the results of mineralogical studies, texture and associated alterations, geochemistry and tectonic setting of volcanic rocks, and   microthermometry of fluid inclusions indicate that  mineralization in the Qarah Changel area is most similar to low sulfidation-type epitermal ore deposits.

Rasht Abad Cu±Au deposit is a part of the Tarom-Hashtjin metallogenic belt in the western Alborz-Azerbaijan zone. The exposed units in the area include volcanic, sub-volcanic calc-alkaline to shoshonitic rocks with Upper Eocene age and belongs to magmatic arcs setting. The most important alterations related to mineralization include low temperature silicification and sericitic alterations. Mineralization with quartz-sulfide veins in the area consist of a series of oxide (hematite), sulfide (chalcopyrite, galena, bornite, covelite), sulfate (barite) and carbonate (malachite, azurite). Fluid inclusions measurements on primary two-phase L+V inclusions determined homogenization temperatures between 138 to 320°C (229°C) and salinity between 2.49 to 9.41wt% (9.41) NaCl eq, evidence of isothermal mixing and dilution. The δ13C (-9.21to -6.81‰) and δ18O (-14 to -15‰) also show the influence of meteoric waters in late carbonate veins. The results of this study show that the high similarity between Rasht Abad and intermediate sulfidation epithermal deposits.

The Sharifabad-Bardeskan copper mineralization is located in northeast of Bardeskan and south section of Sabzevar Zone. Mineralization occurs as vein in the pyroxene andesite, tuff, sandstone and conglomerate of Eocene age, which bearing local sericite - carbonate and silicic alterations and regional propylitic alteration. Mineralization occurs as open space filling, disseminated, veinlets and consists of chalcocite pyrite, chalcopyrite, malachite, azurite with calcite and quartz as gangue minerals. Fluid inclusion studies in calcite show the evidence of mixing trend during the ore formation occurred at a wide range of temperature 200to 437 °C and varying salinity between 0.1 to 9.2 wt.% NaCl equivalent. The stable isotope composition of δ34S fall in a range of -23 to -24.3‰ could be considered as biogenetic sulfur from bacterial sulfate reduction. The δ13C values of calcite vary between -3.4 to -24.5‰ suggest a major contribution of marine carbonates associated igneous carbonates. Copper and sulfide rich hydrothermal fluid has flowed upward through the local faults and permeable interbeds within the Eocene volcanic sequence and formed the mineralized veins. Based on the mineralization, alteration, fluid inclusion and stable isotopes, Sharifabad mineralization is similar to those manto type deposits in Chile.

The Kalchuye Cu-Au deposit is located in the central part of the Urumieh – Dokhtar magmatic arc. This mineralization is mainly hosted by diorite, quartz diorite and andesite rocks. The mineralization is characterized by chalcopyrite, pyrite, galena and magnetite in the hypogen stage followed by chalcocite, covellite, malachite and goethite in supergen stage. According to the geochemical studies, the Lan/Ybn ratio is between 2.2 to 6.3 and Eu/Eu* varies from 0.7 to 1.1; so that intrusions which are the host of mineralization in the Kalchuye region represent characteristics of magmas in the subduction zone (enrichment of LILE, depletion of HFSE in association with negative Ti anomaly). Fluid inclusion data show the temperature of 150-310 ˚C, salinity of 0.1- 4 (wt%NaCl eq.) and depth of 400m, approximately, for the Klchuyeh deposit. Fluid evolution in the Kalchuye exhibits cooling, surface dilution and boiling. Evidences such as bounded and comb textures in quartz, bladed calcite, hydrothermal breccia, propelitic alteration and fluid inclusion information such as temperature and salinity prove the low-sulfidation epithermal nature for the Kalchuye deposition.

Chah-gabri copper deposit is located 90km south of Damghan at Semnan province, in the northeast part of Central Iran at a structural zone bottom of the Turud_Chah Shirin volcanic-sedimentary strip. This strip is eastern-western, in the form of a cross between two faults of Trood in the south and Anjilu in the north. Trend of all units are northwest – southeast) N65̊w (parallel to the zone. Copper mineralization in this area is vein-veinlets and open space fillings along the fracture and faults are composed of lava and tuff units. Minerals host rocks are mainly volcanic lava containers such as basalt andesite, andesite, trachy andesite and less sedimentary pyroclastic. The main minerals forming the deposit include sulfides (Chalcopyrite, pyrite, chalcocite and coveline), carbonate (malachite), iron oxides (hematite, goethite and limonite), and gangue minerals (Calcite, Quartz). Ore mineral textures include: vein-veinlets, open space filling, replacement and disseminated textures.

Study area is located in Semnan province, 90 km south of Damghan city, in geographical coordinates 54° 20´ to 54° 26´ northeast longitude and 35°17´ to 35 ° 23´ north latitude. During several stages of field visit, based on lithology and mineralogical diversity, 58 samples of rock and ore were taken with their geographical coordinates. Of these, 22 are thin sections, 14 are polished sections and 8 are thin - polished sections. Eventually they were prepared and studied. Overall, they were analyzed in the laboratories of Iran Minerals Research and Processing Center (IMIDRO) in which, 4 samples were studied by X-ray diffraction method (XRD), 7 by x-ray fluorescence (XRF) and 8 by ICP- MS method.

The results of geological, mineralogical, structural and textural studies of minerals show that much of the Copper mineralization is in the form of open space filling. Among the host rock components, units with a combination of andesite, basalt andesite and trachy andesite have been observed. Copper mineralization in this area is in the form of chalcopyrite, chalcocite, covolite and natural copper. It also occurs in the form of malachite on surface outcrops. In the study of fluid inclusion, temperature was175 to 200 degrees Celsius, salinity was 4 to 10.5 wt.% equivalent to NaCl and density was 0.9 to 1 g / cm3, which were determined to indicate the epithermal range.

Considering all field and laboratory evidence including host rock composition, texture and mineralization, zones alterations, major and associated metal elements, paragenetic sequence, the geochemistry and thermometry of fluid interconnects. Chahgabri copper deposit is in good compatibility with Manto type deposits, but due to vein ore mineralization, it can be classified as low sulfide vein epithermal hydrothermal deposits.

The Takab-Qorveh magmatic lineament between the Urumieh-Dokhtar and the Sanandaj-Sirjan zones contains important gold mines such as Dashkasan and Zarshuran. The Dashkasan deposit is located in the Kurdistan province and is one of the largest gold deposits in the Middle East domain. The gold is mainly hosted by porphyritic dacite and breccia. In spite of detailed previous studies, there is still debate regarding the genesis of the Dashkasan. Herein, this study present the source and evolution of the mineralizing fluids using the fluid inclusion and stable isotopic investigations. At Dashkasan, the breccia and mineralization are constrained by the steep NNE-SSW-trending faults. Alteration zones on the surface are phyllic, silicification, tourmalinization, argillic and minor propylitic. Sulfide minerals consist of pyrite, marcasite, arseno-pyrite, stibnite, chalcopyrite and to lesser amounts of bornite, sphalerite and galena associated with quartz, tourmaline, sericite, calcite and chalcedony. Result of microthermometry measurements shows a range of homogenization temperatures between 183-260 °C with salinities of 15.97 to 17.06 wt % NaCl equiv. The oxygen isotope composition of fluid in quartz ranges from 6.6 to 9.9 ‰, while, the tourmaline has δ18Ofluid values are in the ranges of 8.5 to 12.3‰. Also, the δDfluid values of the quartz and tourmaline ranges between -51 to -81 and -93 to -111‰, respectively. Integrating with previous studies, all these data, suggest a migration from a porphyry gold system (stage-I) with a magmatic source to a low-sulphidation epithermal (stage-III). Stage-II occurred simultaneously with the collapse and eruption of crater.

Choghart iron deposit is located in central Iran and 12 km north east of Bafgh, 130 km southeast of Yazd city. The dominant host rock in this area is the complex of intermediate-acidic igneous infiltrations and Mafic dykes, which have been highly altered in some parts and are known as metasomatitis. These igneous rocks have been transformed in some places to the extent of the green schist facies. Magnetite is the most abundant oxidizing ore in the region, in layered, massive and diffuse forms in the host rock of Choghart deposit. The main ore mineralization of the deposit occurred in the late Precambrian formations of high-grade (magnetite + apatite + amphibole). The data from the study of fluid transitions in monolithic apatite with magnetite shows that the Changar iron mass canal is in the range of 370 to 385 ° C. The highest salinity rate was found to be 20-39% by weight, equivalent to salt. Field evidence and micro-measurements of fluid transitions in Chaghart mineral deposit apatite show that ore-bearing fluid is very similar to that of magmatic-hydrothermal deposits of gold-copper-iron oxide (IOCG).