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Lithium (Li) is a scarce and technologically important element; the demand for which has recently increased due to its extensive consumption, particularly in manufacturing of Li-ion batteries, renewable energy, and electronics. Li is extracted from brines, pegmatite, and clay minerals; though extraction from brines is economically preferred. More than 200 salt plugs are in the Zagros Mountains which represent potential sources for Li exploration. This preliminary study collected first data on the abundance of Li in the salt plugs in southern Iran, and investigated Li distribution during evaporation of halite-producing brine ponds. The XRD analysis of powdered samples showed that gypsum and halite are the dominant solid phases in the ponds in which Li is concentrated in gypsum, while halite is depleted of Li. ICP-MS and ICP-OES analyses showed that Li in brines is concentrated during the evaporation by factors up to 28 with total contents up to 40 mg kg‒1. The Mg/Li ratio was higher than 70, which makes the brine unsuitable for conventional evaporation extraction techniques which require Mg/Li ratios of less than 6. Considering that 25 mg kg‒1 is a suitable concentration of Li for exploration purposes, the results of this study suggest that with the advancement of extraction techniques, the depletion of presently used high-grade Li reserves, the increasing demand for lithium, the need for extraction from diverse sources, and the exploration of new resources, the salt plug brines have an exploratory potential for Li in the future. [ABSTRACT FROM AUTHOR]

The Miocene Daralu Porphyry Copper Deposits (PCDs) is found associated with other porphyries such as Sarcheshmeh and Meiduk in the Kerman Cenozoic Magmatic Arc (KCMA), southern Iran. In this research, we provided whole-rock geochemical data, characteristics of hydrothermal fluid and sulfur isotope composition of the Daralu intrusive body, and discussed the nature, tectonic setting and fluid evolution of this deposit aiming to investigate its fertility. The Daralu porphyry shows adakites affinity, that is, high Sr/Y and La/Yb ratios and positive Eu anomalies. The REEs patterns indicate a strong fractionation ([La/Yb]n= 28.73). High La/Sm and Dy/Yb ratios suggest enrichment of amphibole and garnet as residual phases in melt source, whereas partial melting of plagioclase increases Eu and Sr in the parent magma. The presence of garnet implies a pressure equivalent to the thickness of more than 40km of crust. To elucidate the evolutionary history of fluids and the origin of the Daralu deposit, we focused on the origin and composition of the fluid through petrography, Raman spectroscopy, and microthermometry studies of fluid inclusions. The fluid inclusions have been divided into four types: vapor (type I), aqueous-vapor (type II), CO2-bearing (type III), and multiphase (type IV). The Raman shifts included 1284 and 1388 cm-1 for CO2 and 2750-3900 cm-1 for H2O. The events such as NaCl supersaturation, exhausting of CO2-rich components, high oxygen fugacity and temperature decreasing through mineralization stages were critical in controlling the fertility of the Daralu PCD. The obtained δ34S data for sulfides yielded an average of +5.5‰. Based on the observed features, it was concluded that Daralu porphyry shares formation conditions with other productive porphyries of the KCMA. [ABSTRACT FROM AUTHOR]

The abundance of mining activities continuously increases mine wastes/tailings that require storage/disposal. It is well understood that the accumulation of tailings around mines, and consequently, their spreading in the environment could cause serious ecological hazards. Reuse and recycling of mine tailing materials, in construction and earthwork applications (such as non-structural building elements, roads), offset possible environmental pollutions and safeguard natural resources. This study investigates experimentally the cement/bentonite stabilization of iron ore tailings from the Golgohar iron ore mine, which is the largest producer of raw (un-smelted) iron products in Iran. A comprehensive series of compaction and uniaxial compression tests was performed on mixtures of cement/bentonite and tailings. Test results reveal that the introduction of cement/bentonite to iron ore tailings requires higher water content for optimum compaction and results in lower dry density. The addition of bentonite increases the unconfined compressive strength (UCS) very little, whereas there is a great strength enhancement for tailing-cement mixtures, particularly after a period of moist curing. The cement-stabilized iron ore tailings may be incorporated in road constructions as they easily fulfill strength requirements of base and subbase course layers, while the bentonite-treated tailings are applicable as cover materials in layered disposal of tailings. [ABSTRACT FROM AUTHOR]

The Bavanat Cu deposit occurs as veins controlled by a NE-trending structure within the Permo-Triassic Surian metamorphic complex (SMC), southwest of Iran. The SMC rocks exposed in the area have undergone greenschist-facies metamorphism. The ore-forming process can be divided into early, middle, and late stages, represented by, respectively, pyrite-quartz, polymetallic sulfide-quartz, and late-stage barren quartz veins. Systematic studies of fluid inclusions (FIs) in the quartz veins found four types: aqueous, mixed aqueous-carbonic, carbonic, and multiphase-bearing inclusions. The FIs of early, middle and late-stages are mainly homogenized at temperatures of 335-417 °C, 230-380 °C, and 190-227 °C, with salinities of 1.1-6.7, 2.9-36.6, and 0.8-2.6 wt.% NaCl equivalent, respectively. The main stage of Cu mineralization is related to the middle-stage, where FIs show evidence of fluid immiscibility. The metal precipitation resulted from a decrease in copper solubility during the fluid immiscibility, cooling, crystallization of multiphase-bearing inclusions, and a small increase in pH. Laser Raman spectroscopy and FIs evidences indicate that the metallogenic system evolved from metamorphic CO (+CH)-rich, relatively high fO (10 to 10 bars) to CO-poor and relatively low fO (10 to 10 bars). Muscovite from the middle-stage veins yields Ar/Ar plateau age of 195.2 ± 1.0 Ma, suggesting that the Cu mineralization at Bavanat formed in the Early Jurassic coeval with the retrograde metamorphic events during the post-early Cimmerian orogeny. [ABSTRACT FROM AUTHOR]

The Iju Cu porphyry is located in the NW part of the Kerman Magmatic Copper Belt (KMCB). It is related to a ~ 9 Ma granodiorite porphyry intrusion, with three main stages of hydrothermal activity. The homogenization temperatures for the fluid inclusions are in the ranges of 200–494 °C, and their salinities vary from 4.0 to 42.8 wt% NaCl equiv., which are typical magmatic-hydrothermal fluids. The δ34S values of sulfides range from −0.4 to +3.2 ‰ (V-CDT), and the δ34S values of anhydrite samples range from +11.6 to +16.8 ‰. The δ34S values of sulfides show a narrow range, implying a homogeneous sulfur source. The oxygen isotopic composition of hydrothermal water in equilibrium with quartz samples ranges from +3.4 to +6.0 ‰ (V -SMOW) consistent with the hydrothermal fluids having a magmatic signature, but diluted with meteoric waters in the main mineralizing stage. The most important factors responsible for metal precipitation in the Iju porphyry deposit are fluid boiling, oxygen fugacity decrease and cooling followed by dilution with meteoric water. The primary fluids of the Iju Cu deposit are characterized by relatively high temperature and moderate salinity, and are CO 2 -rich, indicating a typical post-collisional porphyry system. [ABSTRACT FROM AUTHOR]

[Display omitted] • FIs microthermometry is helpful for deciphering the PT condition of deformation. • The results highlight the correlation between microstructures and fluid inclusions. • Different types of Fls reflect different PT conditions during polyphase deformation. • The findings provide insights about the paleofluids evolution in the SSMB, SW Iran. An investigation into the correlation between microstructural characteristics and deformation temperatures of quartz in the middle crust is of utmost importance in yielding substantial knowledge of the nature of deformation zones. Mylonitic rocks from the Gol-e-Gohar Shear Zone were investigated to infer innovative insights into the ductile deformation pressure–temperature (PT) conditions of the Sanandaj–Sirjan metamorphic rocks within the Zagros, southwest Iran. This approach used a multi-method strategy including quartz c-axis fabrics, recrystallization mechanisms and fluid inclusions (Fls) data. Geothermobarometric analysis based on these data highlight deformational PT conditions ranging from ∼400 to ∼500 °C and P < 5 kbar that correspond to ductile deformation with greenschist to lower-amphibolite conditions at depth of ∼ 12–19 km. Measured opening angles of quartz c-axis fabric and dominance of basal < a > slip system indicate crystal plastic deformation occurred in T > 400 °C. Microstructures highlighting the occurrence of Grain Boundary Migration (GBM) confirm temperature of 500–600 °C. The deduced P–T–salinity Fls history of deformation-related fluid inclusions is highlighted by Fls (B-type) with H 2 O-CO 2 –rich metamorphic fluids. These fluids were trapped during ductile deformation in temperatures ranging from ∼ 355 to ∼ 535 °C and pressure of P < 5 kbar. The petrofabric analyses show that the mylonitic rock in the Gol-e-Gohar shear zone have undergone metamorphism at the amphibolite facies condition, and then followed by a retrograde greenschist facies metamorphism. These results emphasize the utility of microstructural and fluid inclusion techniques to constrain the history of mylonitic rocks exhumation in the deformation zones. [ABSTRACT FROM AUTHOR]

This study presents copper isotope compositions of mineralized whole-rock samples from the Kerman porphyry copper belt (KPCB) southeast of the Urumieh Dokhtar magmatic arc. Samples for this study were specifically collected from the Sar Cheshmeh, Meiduk, Iju, SarKuh, Darreh Zar, Bagh Khoshk, and Jebal Barez deposits and investigated to study the application of Cu isotopes to mineral exploration. While in the leached cap zone of the deposits, δ65Cu values range between −3.41 to 5.82 ‰ (avg. 0.42 ‰), in the supergene enriched zone of these deposits the relatively higher δ65Cu content ranges from 5.18 to 8.71 ‰ (avg. 7.17 ‰), and in the hypogene zone, the intermediate δ65Cu values range from 1.49 to 7.31 ‰ (avg: 4.36 ‰). Most measured δ65Cu values in these investigated porphyry copper deposit are positive, which indicates the presence of a Cu − enriched zone. In the enriched leached cap zones, the δ65Cu of the Darreh Zar and Sar Cheshmeh deposits are overall higher relative to the Iju, Meiduk, SarKuh, and Bagh Khoshk deposits, and these higher δ65Cu values are associated with the highest Cu grade and tonnage in the Sar Cheshmeh and Darreh Zar deposits. It is therefore plausible to conclude that the higher δ65Cu value in the leached areas are diagnostic of the high concentration of copper. These findings are complemented by the presence of Cu (II) carbonates, silicates, and Fe − oxides in each sample that has resulted in the enrichment of 65Cu, relative to the remnant sulfides with a wider copper isotope range. In addition, there is a general shift toward higher δ65Cu isotope values relative to the inferred precursor minerals. The overall apparent weathering and oxidative dissolution is likely to have generated isotopically heavier fluids and lighter residual minerals. The elevated δ65Cu of the bulk samples from porphyry Cu deposits in KPCB is consistent with a preferential loss of 63Cu into fluids during the segregation of aqueous fluid–melt. This is best explained by several pulses of hypogene magmatic fluid which led to repeated enrichment in 65Cu in the magmatic system. It is plausible to conclude that copper isotope values in these mineralized samples can be used as an effective exploration tool to identify buried porphyry Cu systems. • Copper isotopic composition of whole rock samples shows a wide range up to 8 ‰. • High Cu isotope can be an indicator for the presence of an inherited Cu–enriched magma. • Oxidative dissolution generate isotopically heavier fluids and lighter residual minerals. • Whole-rock Cu isotope seem closely related to the Cu grade and tonnage of KPCB deposits. • Whole-rock Cu isotope is a helpful tool for prospecting means ore exploration. [ABSTRACT FROM AUTHOR]

Abstract This investigation of leached caps in Meiduk and Parkam porphyry copper deposits (PCD) in Kerman Cenozoic magmatic arc (KCMA) of SW Iran indicated that the fertility of supergene enrichment zones may be inferred from the mineralogical and geochemical characteristics of their associated leached caps. That is, the indigenous mature leached caps characterized by strong leaching of Cu, large ion lithophile elements (LILEs), and high field strength elements (HFSEs), commonly form above intrusions where supergene enrichment is strongly developed. Mineralogically, these leached caps (e.g., SE Meiduk) are characterized by abundant hematite and minor goethite (Hem:Gt ≈ 5.48), whereas immature leached caps (e.g., NW Meiduk and Parkam) are associated with poorly developed supergene enrichment zones characterized by abundant goethite (Hem:Gt ≈ 0.56 for NW Meiduk and 0.38 for Parkam), boxwork textures, secondary copper minerals and remnant pyrite. Calculated rock quality designation (RQD) from drilling cores in Meiduk deposit also revealed the relation between joint density and the extent of supergene enrichment. Moreover, increasing the rare earth elements (REEs) content in the immature and fewer REEs concentration in the mature leached caps also reflects the fertility of supergene enrichment zone in PCDs. Highlights • The fertility of supergene zone is reflected in the mineralogical and geochemical characteristics of their associated leached caps. • Calculated rock quality designation (RQD) revealed the extent of supergene enrichment. • REEs are the best geochemical indicators for supergene enrichment development. [ABSTRACT FROM AUTHOR]

This study is a 2D basin modeling to determine the petroleum system (i.e. Cretaceous-Neogene play) of the Karanj and Parsi oilfields in the Southern Dezful Embayment, SW Iran. This system is characterized by occurrence of source rocks of Middle Cretaceous, Late Cretaceous and Paleocene to Eocene (Kazhdumi, Pabdeh and Gurpi Formation), reservoirs of Upper Cretaceous and Late Oligocene–Early Miocene (Ilam-Sarvak and Asmari formations), and seals of Paleocene and Miocene (Pabdeh and Gachsaran Formation). Considering temperature, transformation ratio and vitrinite reflectance, the maturity of source rocks (Kazhdumi, Pabdeh and Gurpi Formation) was investigated. A maturity history analysis showed that the maturity of Kazhdumi, Pabdeh and Gurpi Formation started during 70–60 and 4 Ma, respectively. Generation and expulsion of hydrocarbons started ~16 Ma in the Kazhdumi Formation and ~3 Ma in the Pabdeh Formation that continued up to the present. The analysis of the transformation ratio indicates transformation of significant amounts of Kazhdumi source rocks for generating hydrocarbons. Migration of hydrocarbons from the Kazhdumi Formation is mainly vertically upward. From Pabdeh Formation migration is both vertically upward (to the Asmari reservoir) and downwards (to the Ilam-Sarvak reservoir). However, some local traps have formed due to the hydrocarbon accumulation above the faults. Our results reveal that petroleum generation, migration and entrapment occurred at proper timing which facilitated the migration of hydrocarbons and their accumulation in the reservoirs. • This study is a 2D modeling to identify the petroleum system in SW Iran. • Generation and expulsion of hydrocarbons started ~16 Ma in the Kazhdumi Formation. • Some of the produced oil from Kazhdumi Source rock is cracked into gas. • Some traps have formed due to the hydrocarbon accumulation above the faults. [ABSTRACT FROM AUTHOR]

The Miocene Sarkuh porphyry Cu deposit is located in the southwestern part of Urumieh-Dokhtar Magmatic Arc (UDMA) in Iran. Compared with the neighboring giant Sarcheshmeh porphyry Cu deposit, this is a low-grade sub-economic porphyry Cu system (110 million tons @ 0.26 % Cu) characterized by an unusual abundance of magnetite. The present work tried to answer the question of whether or not there are differences in the hydrothermal system of Sarkuh, resulting in the lack of considerable mineralization. In this way, the mineral associations and EMPA data of magnetite were considered to distinguish the different stages of magnetite crystallization reflecting the magmatic-hydrothermal evolution of the Sarkuh deposit. They include (1) magmatic stage magnetite, including magnetite inclusions within primary silicate minerals (i.e., plagioclase and biotite), (2) pre-ore stage magnetite associated with potassic alteration assemblages, (3) main ore stage magnetite tightly associated with sulfide mineralization, and (4) late stage magnetite forming overgrowths on the sulfides. The results of EPMA analysis confirm that magnetite of these four stages differ in Mn, Fe, Ti, Mg, Al, Cr, and V concentrations. Higher V concentrations are found in the magmatic and pre-ore stages, whereas Al and Si reach the highest in the ore and late stages. Our data show that increasing fluid-rock interaction and changes in the oxygen fugacity, especially during the main ore stage extending to the late stage, are key factors controlling the trace element partitioning of magnetite. Most of ore stage magnetite formed at temperatures >500 °C and high temperatures prevailed during it. Magnetite crystallization after the main stage of sulfide mineralization accompanied by (partial) martitization indicate the increase of oxygen fugacity towards the late hydrothermal stage. This could explain why the ore and late stage magnetites show chemical similarities to those from sulfur-poor iron oxide copper‑gold (IOCG) deposits rather than porphyry deposits. • Sarkuh porphyry Cu deposit is characterized by unusual abundance of magnetite. • Four stages of magnetite crystallization could reflect the magmatic-hydrothermal evolution. • Al and Si reach the highest in the ore and late stages. • Ore and late stage magnetites show chemical similarities to sulfur-poor IOCG deposits. [ABSTRACT FROM AUTHOR]

Aim: Documentation of marginal bone resorption caused by implant-supported mandibular overdentures is scarce. This study sought to evaluate marginal bone resorption, survival rate, patient satisfaction, peri-implant soft tissue status, and prosthetic aftercare of mandibular overdentures supported by two vs four implants., Materials and Methods: This retrospective cohort study evaluated 92 edentulous patients presented to the Implant Center of Tehran University of Medical Sciences; out of which, 46 patients received overdentures supported by two Implantium implants (group A), while the remaining 46 received overdentures supported by four Implantium implants (group B). Standard radiographic indices were assessed following the delivery of overdenture and after 2 years of functional loading. Clinical evaluation was performed after 2 years of function. Data were analyzed using the t test (for continuous variables) and the Mann-Whitney test (for ordinal variables)., Results: In group A, two implants were lost in one patient. The groups were not significantly different in terms of clinical or radiographic parameters ( p > 0.05). Patient satisfaction and prosthetic aftercare were not significantly different in groups A and B ( p > 0.05)., Conclusions: During the 2-year evaluation period, the clinical and radiographic parameters were the same in patients who received overdentures supported by two or four implants., Clinical Significance: Successful results may be obtained by the use of mandibular overdentures supported by two or four implants.

Concentrations of total suspended particulate matter, particulate matter with aerodynamic diameter <2.5 μm (PM 2.5 ), particulate matter <10 μm (PM 10 ), and fallout dust were measured at the Iranian Gol-E-Gohar Mining and Industrial Facility. Samples were characterized in terms of mineralogy, morphology, and oxidative potential. Results show that indoor samples exceeded the 24-h PM 2.5 and PM 10 mass concentration limits (35 and 150 µg m -3 , respectively) set by the US National Ambient Air Quality Standards. Calcite, magnetite, tremolite, pyrite, talc, and clay minerals such as kaolinite, vermiculite, and illite are the major phases of the iron ore PM. Accessory minerals are quartz, dolomite, hematite, actinolite, biotite, albite, nimite, laumontite, diopside, and muscovite. The scanning electron microscope structure of fibrous-elongated minerals revealed individual fibers in the range of 1.5 nm to 71.65 µm in length and 0.2 nm to 3.7 µm in diameter. The presence of minerals related to respiratory diseases, such as talc, crystalline silica, and needle-shaped minerals like amphibole asbestos (tremolite and actinolite), strongly suggests the need for detailed health-based studies in the region. The particulate samples show low to medium oxidative potential per unit of mass, in relation to an urban road side control, being more reactive with ascorbate than with glutathione or urate. However, the PM oxidative potential per volume of air is exceptionally high, confirming that the workers are exposed to a considerable oxidative environment. PM released by iron ore mining and processing activities should be considered a potential health risk to the mine workers and nearby employees, and strategies to combat the issue are suggested.