جستجوی مقالات مرتبط با کلیدواژه « fluid inclusions » در نشریات گروه « زمین شناسی »

The ​​Karat iron deposit is located in the vicinity of Sangan mining district, in the Northeast of Iran. The basement rocks of the Karat area include hornfels, metamorphosed limestone, marble, sandstone, siltstone and red shale with interlayers of marl, shale and marl, thick-layered red conglomerate and alluvial deposits. The intrusion of a granite batholith in the sedimentary units of the Karat iron deposit has led to the formation of iron deposits in the margin of this batholith. The most important ore minerals include magnetite, hematite, goethite, limonite and a small amount of sulfide minerals such as pyrite and chalcopyrite. Geochemical data indicate a strong correlation between the Ni, Mg, and V to Fe in mineralization zone, which indicates the magmatic origin of the Karat iron deposit. In order to investigate the characteristics of the ore-forming fluid of the skarn Karat iron deposit fluid inclusions of quartz veins were analyzed. The results show that fluids are mainly (L+V) type, low to medium salinity (4.48 to 16.42% NaCl) and the homogenization temperature of 200 to 390 degrees Celsius. Mineralogical, geochemical, and fluid-inclusion data show that the magmatics, meteoric and metamorphic fluids are responsible for Fe-mineralization in the skarn and Isothermal mixing and surface fluid dilution are main evolution factors in mineralization fluids. It seems that the main phase of mineralization has been occurred during the retrograde stage skarn.

The Arzanfood area is located in southeast of Hamadan city, east of the Alvand granitoid. Based on of Iran geological structure zone, it is located in the Sanandaj - Sirjan zone. Quartz veins occur in the metamorphic rocks, including garnet-mica schist and phyllite, and are related to tectonic activity. The most of fault trends complied with N28W-N62W Zagros zone. In the field, three different types of quartz veins have been identified in the region including: 1) veins with a width of less than 10 cm and a length of several meters within the slate and hornfels rocks, 2) veins with a width of less than 2 meters and a length of less than 20 meters with the host rocks are garnet, micaschists and slate, and 3) veins and lenses with a width of more than 2 meters and a length of more than 20 meters that are present in micaschists rocks. Studies of fluid inclusions in quartz mineral show a homogenization temperature from 98 to 408 ° C and salinity ranges from 3.72 to 22.91 wt. % NaCl. Boiling and dilution with surface water are two processes that have been involved in mineralization. Finally, it can be concluded that quartz indices in the region are the product of hydrothermal activity related to metamorphic processes and quartz was deposited from mineralizing fluids in the empty spaces as a result of temperature and pressure reduction.

The Balestan iron deposit is located about 55 km southeast of Urmia city. The main host rock is the quartz sericite schist unit of the Early Precambrian age. Major mineralization occurred along the schistocytes of the host rock. However, open space filling structure is also abundantly observed in the fault zones. Based on field evidence and microscopic studies, the dominant iron mineralization is in the form of magnetite, which is observed along with pyrite and chalcopyrite. Geochemical investigations revealed that the distribution patterns of trace elements and major oxides are very similar to other hydrothermal iron deposits. The microthermometric studies of fluid inclusions shows an average homogenization temperature and salinity of about 276°C and 7.3 wt% NaCl equivalent, respectively.The variation trends in salinity and Th of fluid inclusions can be explained by a cooling and pressurization of ore-bearing fluids. Also, these data show that the Balestan iron ore deposit is located within the field of mesothermal ore deposits.

Fluid inclusions provide valuable evidence of the formation temperature of minerals, the pressure on their formation environment, the fluids densities that make up the minerals, and the chemical composition of the mineralizing fluids. This data can be used to interpret temperature history, maturity, determination of diagenetic environment, cementation timing, and hydrocarbon migration related to burial history.

In this study, the cores of Asmari reservoir of 7 wells from Ahvaz field (AZ) were used. After checking the appearance characteristics of the samples, 19 double-polished sections with a thickness of 200 to 300 micrometers were prepared. In order to perform microthermometric analysis, at first, all samples were placed in acetone for 24 hours. In the following, after separating the double polished samples from the slide, in order to completely remove the surface contamination, the samples were placed in an ultrasonic device for five minutes in distilled water. After the initial investigation of the occurrence of fluids inclusions in the studied samples, regardless of the size of the fluids involved, 54 intermediate loads of fluids were selected to conduct microthermometric studies. All microthermometric data were obtained using cooling and heating operations on the involved fluids using a Linkam THMSG 600 model stage placed on an Olympus microscope. In addition, in order to determine the amount of UV reflection in the Petroleum Inclusions in the study, the UV light source model U-RFL-T placed on the Olympus microscope was used. After performing microthermometric operations on the fluid’s inclusions, the selected samples were selected for Raman laser spectroscopy analysis to accurately determine the liquid and vapor phases of the Petroleum Inclusions. It should be noted that Raman laser spectroscopy analyzes were performed on microthermometric analyzed samples. All measurements were made using a LABRAM model Raman spectrometer (ISA Jobin Yvon) available in the Fluid inclusions Laboratory of Montanuniversitat University.

Petrographic studies All the samples were subjected to petrography study, which is in terms of the types of single-phase gas, single-phase liquid, two-phase liquid-rich (oil) intermediates. In these samples, hydrocarbon materials can be seen scattered and filling fractures. In terms of origin, it can be seen in different and varied types, primary and secondary false. Microthermometric studies Microthermometry was performed on 54 fluids inclusions. The homogenization temperature of fluid inclusions is between 50 and 362 degrees Celsius. The samples of the Asmari reservoir show the melting temperature of the last ice crystal between -22 and 13.9. The degree of salinity is calculated to be 0.16 to 35% by weight equivalent to table salt. API study In the samples selected from the Asmari reservoir in Ahvaz field, 54 fluid inclusions were identified. These fluid inclusions emitted the following fluorescence spectrum under UV light. The frequency of reflective color is related to green with a value of 55%, which is in the range of 30-40 API degrees, and the value of 40% belongs to blue color, which indicates the range of API degree 40. -50 and only 5% of these colors belong to the yellow color, which indicates the API degree in the range of 20-30. Therefore, in the samples of the Asmari reservoir, the green color with a frequency of 55% has a density of 0.82 to 0.74 g/cm3, which generally indicates oil with a light density. Also, in the second category of these samples, the abundance of fluorescent reflective color, blue color with an abundance of 40%, with a density of less than 0.74 g/cm3, is considered an extremely light oil. Finally, the lowest reflective color abundance of Asmari reservoir samples is yellow with 5% density of 0.9 to 0.82 g/cm3, it is considered a medium density oil. Raman spectroscopy The calculation of liquid phase salinity in petroleum inclusions cargoes using the Raman laser spectroscopy method is dependent on the geometric shape of the spectrum obtained from the liquid phase present in the petroleum inclusions. According to the Cauchy-Lorentz scattering, the Raman spectrum for pure water shows three peaks at cm-13220, cm-13433 and cm-13617. In the samples that were analyzed by Raman spectroscopy, they indicate hydrocarbon compounds in the fluid inclusions.

Based on the petrographic studies conducted on 19 samples (54 fluid inclusions) according to their diversity (primary, secondary), it indicates and confirms the different compositions of the activity of different phases of Asmari reservoir charging. Based on the data obtained from the microthermometric studies, the physicochemical properties of the reservoir, including the last ice melting temperature, homogenization temperature, and salinity of the reservoir were determined. Based on the physicochemical properties of the Asmari reservoir, it shows two temperature ranges, which can be concluded that this reservoir was charged during two phases in two different time periods. One of the reasons confirming this conclusion can be mentioned that the oil of this reservoir has two origins. Also, based on the composition of the phases in the fluid inclusions (two-phase, three-phase with oil, etc.), it is possible to predict the path of charging the reservoir.

The Fatehabad Cu deposit is located in the Khorasan Razavi province, 35 km SE of the Torbat-e Heydariyeh and in the Khaf-Kashmar-Bardaskan metal belt. The vein and veinlet mineralization consist of chalcopyrite, pyrite, magnetite, chalcocite, bornite, covellite, malachite and iron oxides associated with siliceous-sericite, argillite and propylitic alteration in the volcanic rocks formed parallel to the sub-faults that branch off from the Dorouneh fault. The similar pattern of REE and trace elements in the mineralized veins and associated volcanic rocks suggests an magmatic-hydrothermal origin of the ore elements. In the vein system of Fathabad district, quartz, pyrite, chalcopyrite, and magnetite veins with propylitic alteration in the early stage of mineralization, quartz, pyrite, chalcopyrite and magnetite veins with sericite alteration in the main stage of mineralization and quartz, pyrite and chalcopyrite veins were identified along with argillic and iron oxide alterations. Calcite veins along with sericite and iron oxide alterations were also identified in the late stage of mineralization. The enrichment of trace, LREEs/HREEs ratio, positive Eu anomalyand negative Ce anomaly, indicate reducing conditions and a high pH of the mineralized fluids. Fluid inclusion studies with low salinity (13.9 to 4.74 wt% NaCl eqv.) and low temperature (111 to 192 oC) indicate dilution and mixing of the sulfur- and element-rich magmatic-hydrothermal fluid with meteoric water, leading leaching and precipitation of trace, rare and copper elements. The δ34S isotopes values (-1.58 to -2.86‰) in the chalcopyrite minerals indicate the magmatic origin of sulfur. The geology, geochemistry, and fluid inclusions evidences indicate that the Fathabad Cu deposit is belong to epithermal style mineral systems.

Zavarian gold deposit is located 60 km SW of Qom and in Central Iran geotectonic zone. The basement rocks of the area include volcanic units of Miocene- Pliocene (MPb), volcanic andesite units of Miocene- Pliocene (MPan), volcanic- pyroclastic units of Miocene- Pliocene (MPVP), pyroclastic units of Miocene- Pliocene and recent alluvium. The plutonic rocks of the area are granodiorite-tonalite. The intruded dykes are subdivided to andesite dykes (DY1) and dacite dyke (DY2). The main alterations are advanced argillic, alunitization, propylitic, sericitic and silicification. Gold mineralization has been occurred in andesite and dacite dykes. Au-mineralization are mostly vein, breccia and replacement type. Ore minerals include magnetite, hematite, Fe-hydro-oxides, chalcopyrite, purite and bornite which are host of Au. Geochemical data show that the average content of Au is1.98ppm. Fluid inclusions were investigated in quartz which are associated by ore minerals. These fluid inclusions are generally two-phase of fluid-rich (L + V). The results of analyzes showed that the salinity contents vary between 0.87 to 44.06% NaCl. The homogenization temperature varies between 138 and 383 ° C. The data suggest that the hydrothermal fluids which are responsible for mineralization have low to medium temperature and salinity. It is compatible to primary magmatic hydrothermal fluids which have been mixed probably to metamorphic and meteoric fluids. Mineralogical, geochemical and fluid inclusions data show that gold mineralization in the area is epithermal high sulfide type.

Hesar gold mining area is located in Iran Alborz-Azerbaijan zone. The predominant lithology in the mineral range is volcanic, subvolcanic, and sedimentary rocks of the Cenozoic period, which include volcanic and pyroclastic rocks, andesite-trachyandesite, basalt, eicombrite, and tuffs of the Eocene age and related to the Laramid orogenic phase under the influence of Laramide. Expansion phase of volcanic lava that erupts from several fissures and emerges in the form of delirious dykes and floods and stocks, mainly dacite, rhyodacity with Oligocene age, and alterations related to these masses such as silicification, pyritization and caudal formation Major mineralization in the study area includes pyrite, goethite, magnetite and gold, which is mineralized in two phases and is mainly selective and dispersed. Gold mineralization is the result of the decomposition of pyrite and arsenic pyrite, which is free in the field. The rock has been found to be related to the second phase of volcanic and semi-volcanic outcrops of the Oligomocene age. The results obtained from microscopy studies of fluid shortcuts in quartz mineral indicate that the homogenization temperature varies in the range of 140 to 260 ° C and also the melting temperature of the last ice crystal changes from -0.1 to -9. ° C and salinity is between 0.18 to 14% by weight equivalent of NaCl with a frequency range of 2 to 6% by weight equivalent of NaCl.

The Khoynaroud area is located about 25 km north of Varzaghan city in the Arasbaran metallogenic district. The quartz vein-veinlets host rocks are quartz monzonite and diorite. Distinctive alterations around the quartz vein-veinlets include silicic, phyllic, argillic, and propylitic types. The quartz vein-veinlets display ribbon, comb, open-space filling, vuggy, and brecciated textures. The mineralization took place during two stages, hypogene and supergene. The hypogene minerals include sulfide minerals (chalcopyrite, pyrite, and bornite) and gold, which are associated with supergene minerals such as Fe oxides-hydroxides (goethite, hematite, and jarosite), copper carbonates (malachite and azurite), and secondary copper sulfides (covellite and chalcocite). Study of microthermometry on liquid-rich two-phase fluid inclusions in quartz mineral coexisting with mineralization indicates that values of salinity of fluid inclusions vary from 8 to 20 wt%. NaCl equiv and values of homogenization temperature of fluid inclusions range from 140º to 380ºC. According to the microthermometric data, the effective ligands in transporting metals are chloride and sulfide and the phenomenon of boiling, cooling, and surface fluid dilution are the most important mechanisms in the deposition of ore minerals. Study of geological, alteration, mineralogical, textural, and fluid inclusion shows that the mineralization in the Khoynaroud area is very similar to epithermal deposits of the low-sulfidation type.

The Neyzar lead-zinc-barium deposit is located about 20 km east of Eshgabad city (South-Khorasan Province, east Iran) and is a part of Tabas-Pushte Badam metallogenic belt. This deposit is hosted by carbonate units of Jamal (Permian) and Shotori (Triassic) Formations. Mineralization was mainly controlled by structural factors (thrust faults) in this deposit. Galena, sphalerite and barite are the principal ore minerals with minor amounts of minerals such as calcite, dolomite, quartz, fluorite, malachite, cerussite, covellite, hemimorphite, hematite, goethite, and manganese oxides. The micro-thermometric studies, using fluid inclusions, on calcite and barite crystals were carried out in this deposit. Both calcite and barite minerals are co-existed and co-genetic with Pb-Zn sulfide mineralization occurrence. Petrographic observations of fluid inclusions show that most of them are of liquid-rich two-phase type. Based upon micro-thermometric analysis, the homogenization temperatures of the fluid inclusions in calcite and barite crystals vary from 120 to 220ºC and from 119 to 199ºC, respectively. The salinities of the fluid inclusions in calcite and barite crystals also show changes within the range of 10.12-23.5 and 19.6-23.1 wt% NaCl eq., respectively. In general, the microthermometric investigations revealed that simple cooling and boiling were the main evolutionary trend for deposition of the ore and gangue minerals by sedimentary-derived hydrothermal fluids. Based on the results obtained from field observations, mineralogy, structure and texture and micro-thermometric data, the Pb-Zn-Ba deposit in the Neyzar area is very similar to those of the Mississippi Valley-type (MVT).

The Kamar-Gov study district is located south of Hashtjin city in the Ardabil Province (NW Iran). The geological units in this district include lavas (with composition of basaltic trachy-andesite to rhyolite), sub-volcanic rocks (as dyke and stock with composition of porphyritic trachy-andesite and trachyte) and crystal, vitric (lithic) tuffs (intermediate and felsic composition). Extensive zones of silicic, sericitic-argillic, advanced-argillic, and chloritic alteration have formed in these rocks. Pyrite is the prevalent metal mineral in the study area and approximately extended in all rock units. Besides pyrite, chalcopyrite, chalcocite, galena, sphalerite, hematite, and magnetite are also present. Covellite, digenite, and goethite are supergene minerals. Ore minerals have formed in crystal, vitric tuff and rhyolite as veinlet, dissemination, strata-bound dissemination, and inside silicic veins/veinlets. Three types of primary fluid inclusions are present within quartz minerals of silicic veins/veinlets and accompanied by disseminated ore minerals, including liquid-rich two phases, vapor-rich two-phases, and salt-saturated three-phase fluid inclusions (liquid, vapor, and halite + sylvite). Micro-thermometric analysis of these fluid inclusions shows the salinity of 1.05-14 wt% NaCl equivalents with the highest frequency of homogenization temperatures between 200 and 300 °C. The ore formation type is similar to intermediate sulfidation epithermal deposits, based on features like the vein-veinlet shape of ore mineralization, colloform and crustiform textures, base metal mineralization, the mineral assemblage of kaolinite – muscovite – pyrite ± sphalerite, intermediate salinity and temperature of the fluid, and probable effect of the boiling process.

The Lapeh-Zanak copper deposit is located about 15 km east of Tehran, in the southern part of the Central Alborz Zone. The rock units exposed in this area include a sequence of volcanic and pyroclastic rocks (basalt, andesite, trachy-andesite and dacitic and vitric tuff) belonging to the Fajan Formation with the Paleocene-Lower Eocene age, which are cut by subvolcanic igneous masses with a composition of micromonzodiorite-gabbro. Copper mineralization in the Lepeh-Zanak deposit occurred in the form of quartz veins-veinlets (± carbonate and barite) along with silicic, argillic, carbonate and propylitic alterations in andesite-trachyandesite rocks. Vein-veinlet and breccia structures and textures are very common in the copper- bearing ore in this deposit. The mineralogy of ore is simple and includes primary minerals of pyrite, chalcopyrite, magnetite, hematite and rutile, which are accompanied by secondary minerals such as digenite, covellite, malachite, and iron hydroxide compounds. The fluid inclusion studies of quartz and barite minerals in copper-bearing ores and barite veins indicate that majority of primary inclusions are two-phase liquid-rich (L+V). Microthermometric studies show that the homogenization temperatures in quartz and barite vary in the range of 100 to 198 and 110 to 207 °C, respectively. Salinity in the primary inclusions of these two minerals shows the range from 0.88 to 8.55 and 4.96 to 7.86% wt% NaCl eq., respectively. Salinity in quartz and barite minerals is in the range of 0.88 to 8.55 and 4.96 to 7.86 wt% NaCl eq., respectively. Based on the results of microthermometric of fluid inclusions, cooling and dilution of hydrothermal fluids with atmospheric waters are the main reasons for the deposition of minerals in the studied deposit. The combination of the results obtained from geological, mineralogical, alteration and fluid inclusions reveals that the Lapeh-Zanak copper deposit has most similar to low-intermediate sulfidation epitermal-type deposits.

The Saveh-Kashan-Qom copper belt, in the northern part of the Urumieh-Dokhtar Magmatic Arc (UDMA) consists of two of the oldest (gold and copper) zones in Iran (Samani, 1998; Rajabpour et al., 2017) where Upper Eocene-Oligocene Mard Abad-Bouin Zahra volcanic suite is situated. This volcanic suite hosts several copper deposits including Jarou, Gomosh Dasht, Ghezel Cheshme, Bidestan and Afshar Abad that are known as the "Kuh-e-Jarou Mining District". The Kuh-e-Jarou Mining District has a total potential ore reserve of 2 Mt Cu with an average grade of 3 wt.% (Zar-Azin Gostar Consultant Engineering Co., 2009). Upper Eocene volcanic and pyroclastic rocks of rhyodacite, trachyandesite, andesite, and trachytic tuff with high-K calc-alkaline to shoshonitic affinity consist of the main host rocks for Cu mineralization. These units are primarily intruded by post Eocene intrusive bodies.  The geochemistry and genesis of ore bodies have not been fully understood since most previous studies in this area have been focused on petrology of volcanic and intrusive rocks. Moreover, the main purpose of this study is to investigate mineralization style, geometry, and textural-structural features of orebodies, alterations, and fluid inclusions with implication for genesis of Jarou, Gomosh Dasht, Ghezel Cheshme, Bidestan and Afshar Abad copper deposits. In addition, this research provides more insight into understanding geology and mineralization conditions in the study area with an implication for future exploration.

Seventeen thin polished sections from the ores and the host rocks were prepared and they were studied by a transmitted/reflected polarizing microscope in the Iran Mineral Processing Research Center (Karaj, Iran). Five rock powdered samples were also analyzed using X-ray diffraction (XRD) spectrometry (X′ pert Philips) in order to identify the mineralogy of clay minerals in the mineralogy laboratory of Salamanca University (Spain). Fluid inclusion microthermometry was performed using a Linkam THMS600 heating-freezing stage (-190 to +600 °C) mounted on a ZEISS Axioplan2 microscope in the fluid inclusion laboratory of the Iranian Mineral Processing Research Center (Karaj, Iran). Salinities (wt.% NaCl eq.), density (g/cm3) and pressure (bars) were calculated using the FLINCOR v.1.4 (Brown, 1989) and FLUIDS (Bakker, 2012).

The orebody is controlled by a series of feather-like ruptures and faults and its dominant mineral compositions are chalcopyrite and chalcocite with minor amounts of pyrite, galena, bornite and sphalerite. The gangue minerals are quartz, barite, calcite and chlorite. Four types of hydrothermal alterations including chloritization, sulfidization, silicification and epidotization were recognized. Based on field and petrographic studies, three mineralization stages were distinguished including (1) the pre-ore mineralization stage characterized by fine-grained disseminated pyrites, (2) the main hydrothermal stage consisting of three substages: I) an early quartz-chalcopyrite ± bornite vein, II) middle bornite-chalcocite ± covellite breccia ore, III) late galena and sphalerite inclusions, and (3) late-stage barite and calcite veins.Based on petrographic studies, five types of aqueous fluid inclusions have been distinguished in the quartz-chalcopyrite ± bornite and barite veins including two-phase liquid-rich (LV), two-phase vapor-rich (VL), liquid monophase (L), vapor monophase (V) and minor halite-bearing liquid-rich fluid inclusions (LVS). The results show that parental fluids with a density of >1 g/cm3 and an approximate depth of 400 meters were formed and they were followed by fluid inclusions with a density of <1 g/cm3 and a depth of <300 meters due to fluid depressurization, faults. Moreover, introducing low temperature meteoric waters have caused fluid mixing and subsequently copper ore deposition (Henley et al., 2015; Cheng et al., 2019). Considering all geological mineralization styles, textures and structures of the orebody, types of alteration and fluid inclusions in copper deposits of the Kuh-e-Jarou Mining District, it can be suggested that these deposits have similarities with the Manto-type copper deposits in Chile or volcanic red beds in northern America.

The Zamin Hossein copper deposit, as a part of the Dehaj- Sarduiyeh metallogenic belt, is located about 170 km southeast of Kerman city. This deposit is accompanied by Eocene volcanic (andesite, andesi-basalt and pyroclastic) and Eocene intrusive body (granodiorite and granite). The propylitic, sericitic, argillic-sericitic and silicic alterations are associated with this deposit. Chalcopyrite and pyrite are the most important hypogene sulfide minerals which are accompanied by supergene mineral assemblages such as goethite, hematite, limonite, malachite, and azurite. The hypogene minerals show generally vein-veinlet, stockwork and crustiform textures. The microthermometric studies in quartz crystalscogenetic with the ore minerals revealed four types of fluid inclusions on the basis of phase content: 1-( L-V), 2-(L-V-S), 3-(V-L), and 4-(V). The results of microthermometric analyses revealed that the fluid inclusions have a wide range of Th (170°C to 530°C). The L-V-S type fluid inclusions displayed Th and salinity ranges of 190-473°C and 31.4-55.6 wt% NaCl eq., respectively. The liquid-rich 2-phase inclusions (L-V) show salinities within the range of 1.74-6.45 wt% NaCl eq. Based upon microthermometric data, boiling, mixing, and simple cooling of the fluids were the essential mechanisms in deposition and evolution of this deposit. The ore-forming fluids were probably of magmatic and mixed magmatic-meteoric sources. According to the structural and textural aspects, alteration and mineralization of mineral assemblages and microthermometric data, the Zamin Hossein ore deposit can be categorized as porphyry copper-type.

Hormuz series in Zendan salt dome, Neoprotozoic-Early Cambrian rocks is located near Bandar-e-Lengeh in western Hormozgan Province. In this salt dome, iron calcic skarns are present near the basic igneous bodies that have copper hydrothermal deposits. Carbonate sedimentary sequences, carbonate tuffs and igneous rocks are the host rocks of these skarns. The calcsilicates in the endoskarn include grandite garnets, feldspars, clinozoicite/epidotes, actinolite, wollastonite and vesuvanite. The calcsilicates in exoskarns are garnets and is mostly andradite, epidote, actinolite and wollastonite. Based on microprobe analysis, the type of garnet within skarn varies from And30Gross70 to And100Gross0. Based on crystal chemistry study, the elements such as Zn, Mn, Cu in exoskarns and endoskarns have a systematicaly distribution. Fluid inclusions study of the andradite mineral have indicated that Zendan skarns are formed at temperatures of 600 to 650°C.

Oilgocene-Miocene celestite occurrences are observed across the carbonate-evaporite formations of Asmari and Gachsaran in the Zagros fold - thrust belt. The aim of this research is the study of fluid inclusions in our celestite deposits (Tortab, Tarak, Likak and Babamohamad) to reveal the nature of ore-forming fluids. Abundant structures including: geodic and vein-like structures as open-space filling along with replacement textures like mosaic and vein-like in a carbonate matrix are present. Moreover, celestite, calcite, gypsum and anhydrite are observed as the major minerals in this deposits. Based on petrographic studies, 5 groups of fluid inclusions were recognised, which are categorized as: Liquid mono phase (L), vapour mono phase (V), liquid-rich two phase (LV), vapor-rich two phase (VL) and multi-phase fluids (LVS). The results obtained from the study of microthermometry data show 134.3 to 291.8°C as homogenisation temperatures and salinities of 2.5-18.17 wt%, NaCl equ, all are involved in forming celestite. Based on the results of microthermometry data, it can be deduced that formation mechanism of celestite is resulted from reaction between fluid and rocks of the area. Moreover, tectonic activities such as uplift and diagenesis of beds along with dissolution of minerals have caused release of strontium in the fluids responsible for ore-forming. This has generally undertaken by two fluids of meteoric and brine origins over different stages of ore-formation, replacing anhydrite with strontium at high temperatures during late- diagenetic and epigenetic processes.

Senjedeh gold mine is located 60 km southwest of Delijan in the central part of the Sanandaj-Sirjan zone (SSZ). This is one of the active mines of the Muteh mineral area. The gold mineralization in the study area occurred as quartz- sulfide veins and veinlets along N40W tending, NE dipping normal faults in metarhyolite host rock. The most important hydrothermal alteration types are sericitization, kaolinitization, silicification and sulfidization, which silicified and sulfide alterations are developed in the inner parts of the fault zones adjacent to the mineralized zones. Five group of fluid inclusion can be identified based on fluid inclusion petrography in Senjedeh, which main primary fluid inclusion is the two-phase fluid (L + V) with dominant phases of (H2O) and (CO2). Evidences from fluid inclusion microthermometry studies indicate the contribution of CO2 bearing ore-forming fluids. They are characterized by the mean homogenization temperature of 300oC, and average salinity of 11 % wt NaCl. They are genetically linked to the generation of metamorphic fluids that are typically characterized by low salinity and mixed H2O–CO2 compositions. Results from petrography, temperature and fluid inclusion homogenization (homogenization to fluid) indicate that released fluids during progressive metamorphism have been mixed with magmatic fluids and meteoritic water, which penetrateed up to a few kilometers through faults. These processes are responsible for alteration and mineralization along normal faults. Based on the evidences of geology, alteration and microthermometry, and comparing with Iran and world's gold deposits, this mine can be considered as an orogenic gold mineralization.

Bozhan area is located in southernmost parts of the eastern Alborz mountain range in NE Iran and is part of the Binaloud structural zone. Geology of the study area include andesitic, trachyte, basaltic and basalt-andesite lavas, which are accompanied by intrusive, subvolcanic, and pyroclastic rocks. These rocks have undergone propylitic alteration. Mineralization occurs mainly along silicic and carbonate veinlets and has a variety of open space-filling, coliforms, brecciate, and vein-veinlets texture. Chalcopyrite is the most important and abundant sulfide mineral in these veins. Microthermometeric investagations were conducted on and in liquid-rich (L+V) fluids. Homogenization experiments revealed a temperature range of 195 to 262 ° C for the studied inclusion and salinity ranges from 10.61 to 14.67% NaCl equivalent. Reduction temperature and cooling are the most important factors in the deposition of metals along with the ore-fluid in the Bozhan exploration area. Meanwhile, mineralization in the Bozhan exploration area has a vein-veinlets trend that is consistent with existing fractures. Based on field observation, mineralogy, structure, texture and fluid inclusion, the Bozhan exploration area can be considered as epithermal vein systems.

The Mahoor area is located about 135 km southwest of Nehbandan city, Khorasan Jonoobi Province, and in the central Lut block volcano-plutonic belt.  The intrusion of an Oligocene granitoid pluton with diorite, quartz diorite, quartz monzodiorite, and quartz monzonite into Paleocene-Eocene volcanic rocks that led to alteration and mineralization. Hydrothermal alteration zones consist of argillic (clay minerals), propylitic (chlorite, sericite, calcite, epidote), phyllic (quartz, sericite, pyrite), and silicification. The main ore minerals include sphalerite, chalcopyrite, magnetite, pyrite, stibnite, tetrahedrite, jamesonite, covellite, cubanite, arsenopyrite and galena, occurring as veinlets and disseminations. According to crosscutting relationships, two type of veinlet have been identified at deep levels of Mahoor deposit. Type (1) Quartz + sphalerite+ pyrite ± chalcopyrite, and type (2) Quartz +pyrite +chalcopyrite± sphalerite. The homogenization temperature and salinity of fluid inclusions in type 1 of veinlets range from 315 to 575°C and 6.8 to 21.2 wt. % equivalent NaCl, respectively. Fluid inclusions in type 2 of veinlets show homogenization temperature and salinity from 177 to 454°C and 7.9 to 20.2 wt. % equivalents NaCl, respectively. The microthermometric data indicate that the ore forming hydrothermal solution evolved through boiling events and mixing of magmatic fluids with meteoric waters. Sulfur isotopic values of pyrite and chalcopyrite vary from 1.8‰ to 3.15‰, suggesting that S was derived from a magmatic source. Geology, alteration, mineralization, fluid inclusion, and stable isotope studies indicate that mineralization in Mahoor area occurred as porphyry system.

Kushk sulfide Zn-Pb ore deposit is located in the Posht-e-Badam block, in the central Iranian tectono-magmatic zone. The host rocks of the ore deposit include shale, sandstone and dolomite. In order to investigate the physicochemical condition controlling the formation of the sulfide ore, a number of fluid inclusions were gathered from silicic thin layers. The silicic contents of the samples have contemporaneously been deposited with shale and sulfide minerals mainly in the footwall and the main mineralized horizon. In this research, the general properties of fluid inclusions in the ore-forming system are taken into account and the interpretation of these data in terms of fluid evolution processes is discussed. Considering the syngenetic formation of the silicic thin layers and the mineralized shale, a similar formation condition can be considered for both of these units.  Based on the results, two types of fluids were involved in the formation of the silicic thin layers, including fluid 1 that is characterized by higher salinity (av. 38.8% NaCl.eq) and is thought to transport the metals chloride complexes and fluid 2 with lower salinity (av. 4.46% NaCl.eq) and is thought to carry sulfide species. Part of sulfide in this type of fluid could be originated from bacterial activity. Isothermal mixing of the two fluids sequencially resulted in destabilization of chloride complexes of chalcophile elements, the reaction between the elements and sulfur originated from the low salinity fluid and formation of the sulfide ore.  

Antimony-Bandan Mining Area of ​​Niagara is located in the Central Iranian Zone and the boundary of the Lut Block and Tabas Block. The dominant lithology in the Antimony Band - Mining area is metamorphic limestones, slits, sandstones and much of the salt and alluvial sediment area. Mineralization of stibenite with galena, pyrite, iron oxide and hydroxide minerals, quartz, barite, and calcite with tissues such as vacuum fillers, veins, shear and dispersed in host rock of Antimony-Bandang Mining Mineral Range. Is. Mineralization has occurred in the Niemannian Antimony Mineral Range at the intervals of marbles from limestone and dolomite metamorphism. The results of quartz mineral microscopy studies indicate that the homogenization temperature of 150 to 265 ° C was detected, the melting temperature of the last ice crystal was -0.3 to -7.5 ° C, and The salinity level of 0.5 to 11 wt% NaCl has been calculated with frequency range of 2 to 3 wt% NaCl. According to statistical, microscopic, and thermometric evidence, the probable genesis of the Antimony-Bond Nangan mineral range is likely to be in the epithermal ore deposit.