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The Middle Eocene Senj Mo–Cu deposit (1.3 Mt at 1.5 wt % Cu and 0.2 wt % Mo) is located in the central Alborz magmatic belt, northern Iran. Mineralization is characterized by multistage veins, which are hosted in volcanic and volcano-sedimentary strata of the Karaj Formation (c. 41–45 Ma), genetically associated with the Senj Mafic Sill (c. 40 Ma). Four generations of veins are documented based on mineral assemblages and cross-cutting relationships, sequentially: quartz–biotite–chalcopyrite (QBC veins), quartz–molybdenum (QM veins), quartz–pyrite (QP veins) and late calcite (LC veins). Three types of fluid inclusions (FIs) are present in multistage veins: liquid-rich two-phase (L-type), vapour-rich two-phase (V-type) and solid-bearing multi-phase (S-type) inclusions. FIs in the QBC and QM veins are predominantly V-type and S-type, together with minor L-type, whereas the QP and LC vein minerals only contain L-type fluid inclusions. The homogenization temperatures of FIs from QBC to LC veins vary from 320 to 425 °C, 308 to 390 °C, 214 to 288 °C and 145 to 243 °C, and their salinities range from 5.3 to 49.0, 6.2 to 39.7, 5.7 to 13.0, and 2.1 to 7.2 wt % NaCl equiv., respectively. The H–O–C isotope compositions favour a dominantly magmatic origin for the hydrothermal fluids, which were gradually diluted by meteoric waters. The S–Pb isotope data of sulphide minerals indicate that the sulphur and metals were sourced from a deep-seated magmatic reservoir. The Senj Mafic Sill and associated Mo–Cu mineralization was developed in a back-arc extension regime, which faults and crustal fracture systems served as conduits for hydrothermal fluid circulation and Mo-rich veining.

The Arasbaran metallogenic zone in northern Iran is part of the Alborz–Azerbaijan magmatic zone, which developed along the southern margin of Eurasia during the Early Mesozoic–Late Cenozoic. This region hosts precious and base metal mineralization, including porphyry, skarn, and epithermal copper, molybdenum, and gold deposits. Rare earth element variations across all the deposits are similar, indicating a similar source for these elements. The north-west trending belt comprising the Nabijan to the Sonajil deposits consistently shows chiefly alkaline conditions of formation. Fluid inclusion studies indicate that both high and low temperature hydrothermal fluids participated in the formation of all of the deposits. The mineralization age decreases from north to south and east to west and, although metal zonation is complex, the Cu–Au association post-dated the Cu–Mo mineralization reflecting that the ore fluid evolved in terms of both cooling and chemical changes due to fluid–fluid and fluid–rock interactions. In this region most deposits record a concentric zonation, with the centres preserving porphyry and skarn deposits and deposits becoming progressively epithermal toward the outer parts of the mineralizing system. According to this, the mineralization age decreases from the porphyry and skarn deposits to the epithermal deposits. The homogenization temperature and salinity both decrease from the centre to the outer zone. The pattern of homogenization temperature zonation, which is concordant with salinity zonation, suggests that fluids migrated up-dip and towards the margins of the zonation system.

Subduction of Neo-Tethys lithosphere beneath the Iranian plateau during Neogene led to the formation of a NW-SE trending volcano-plutonic zone called Urumieh-Dokhtar magmatic assemblage (UDMA). The Takht granodiorite (NE of Hamedan Province, western Iran) belongs to the UDMA and has geochemical properties of post-collisional granitoids that was formed after the collision of Arabian and Iranian plateaus. This body contains rounded mafic micro-granular enclaves with relatively gradational rims indicating the effect of magma mixing/mingling in formation of the granodiorite body. The determination of U-Pb zircon age proved the Takht granodiorite was formed at Miocene (16.8 ± 0.24 Ma). The Nd-Sr isotope ratios and Sr/Nd, Nb/La and Th/U ratios of the granodiorite confirmed the magma was formed mainly by melting of continental crust, and its enclaves originated from a mantle derived mafic magma. Samples show negative anomalies in Nb, Sr, Ti, P and Eu, whereas positive anomalies in Th, K, Zr, Yb and Rb that reveals contribution of mantle and crustal materials in their generation. The Takht granodiorite has geochemical features of A2-type granites and also shows properties of both the volcanic arc and within plate magmatism association granitoids (high levels of LILEs and HFSEs). Regarding this interpretation and also post-collisional tectonic regime, it can be concluded that post-collision extensions caused deep faults in the UDMA that let mantle derived magmas rise up to the thicken crust. Such magma triggered melting in the middle crustal levels and was contaminated with crustal materials to generate granodiorite and enclave magmas respectively. The results of the current study decipher collision between the Arabian and the Iranian plateaus occurred before Miocene and the magmatism in the UDMA continued after closure of Neo-Tethys.

Situated about 130 km northeast of Tabriz (northwest Iran), the Mazra’eh Shadi deposit is in the Arasbaran metallogenic belt (AAB). Intrusion of subvolcanic rocks, such as quartz monzodiorite-diorite porphyry, into Eocene volcanic and volcano-sedimentary units led to mineralisation and alteration. Mineralisation can be subdivided into a porphyry system and Au-bearing quartz veins within andesite and trachyandesite which is controlled by fault distribution. Rock samples from quartz veins show maximum values of Au (17100 ppb), Pb (21100 ppm), Ag (9.43ppm), Cu (611ppm) and Zn (333 ppm). Au is strongly correlated with Ag, Zn and Pb. In the Au-bearing quartz veins, factor group 1 indicates a strong correlation between Au, Pb, Ag, Zn and W. Factor group 2 indicates a correlation between Cu, Te, Sb and Zn, while factor group 3 comprises Mo and As. Based on Spearman correlation coefficients, Sb and Te can be very good indicator minerals for Au, Ag and Pb epithermal mineralisation in the study area. The zoning pattern shows clearly that base metals, such as Cu, Pb, Zn and Mo, occur at the deepest levels, whereas Au and Ag are found at higher elevations than base metals in boreholes in northern Mazra’eh Shadi. This observation contrasts with the typical zoning pattern caused by boiling in epithermal veins. At Mazra’eh Shadi, quartz veins containing co-existing liquid-rich and vapour-rich inclusions, as strong evidence of boiling during hydrothermal evolution, have relatively high Au grades (up to 813 ppb). In the quartz veins, Au is strongly correlated with Ag, and these elements are in the same group with Fe and S. Mineralisation of Au and Ag is a result of pyrite precipitation, boiling of hydrothermal fluids and a pH decrease.

The Almogholagh batholith in the northern Sanandaj-Sirjan magmatic–metamorphic zone comprises three intrusive bodies (gabbroic diorite, quartz syenite, and quartz monzonite) that were generated during the northeastward subduction of Neo-Tethys beneath the Iranian sector of the Eurasian plate. These bodies intruded at different time phases and are related to post-collision magmatism. The quartz syenite and quartz monzonite rocks with specifications of metaluminous, generally ferroan, alkalic to alkali-calcic types, high content of Na 2 O + K 2 O, Zr, Ce, Ga, Y, Nb, Ta, and rare earth elements, and depleted in Eu, Sr, and Ti show borderline characteristics between A 1 and A 2 types granitoids but with more affinity to A 2 type. The gabbroic dioritic rocks show borderline specifications between A 1 and I types rocks but with more affinity to I type. Distinctive spiked peak patterns in spider diagrams accompanied by (La/Yb) CN values equal to 2.44 to 6.11 and a Ba/La ratio >3 indicate the magmatism activity in the volcanic arc environment. The characteristics (Ba/Rb) PN PN 143 Nd/ 144 Nd > 0.512638 in some samples, e t Nd > 0, e t Sr > 0, and high content of Nb, Ta, and Zr (589 ppm) demonstrate the involvement of the mantle source, subducted slab fluids, high flux of mantle-derived halogen-rich volatiles, and contamination within the crust during the petrogenesis of intrusions. After the initial collision, the operation of minor subduction (with slab break-off) or foundering of the lithospheric mantle (delamination) occurred because of asthenospheric upwelling and heat flows in the mantle in the Sanandaj-Sirjan zone. Stretch and local disruptions were created by these heat flows; simultaneously, magma was formed and ascended upward.

The present study focuses on the Late Cretaceous Bidgol bauxite deposit in the Zagros Simply Fold Belt, SW Iran. The orebody is located in the eroded major NW–SE trending Koh-e-Hosseyn anticline and hosted as discontinuous stratified layers and lenses within the upper member of the Cenomanian–Turonian Sarvak Formation. Detailed mineralogical analysis reveals that diaspore, hematite, goethite, anatase, clinochlore, chamosite, and calcite are the major mineral components accompanied by minor amounts of detrital and REE-bearing minerals such as rutile, zircon and parisite. The ore texture suggest that the bauxite material has an authigenic origin but in some parts it has been transported short distances from a primary in situ environment and redeposited in karstic depressions. The spheroidal pisolites of the Bidgol bauxite formed under conditions of low water activity, favouring the formation of large diaspore cores and a single dry-to-wet climatic fluctuation. The mass change calculations relative to the immobile element Ti show that elements such as Si, Fe, Mg, K, Na and Sr are leached out of the weathered system; Al, Ni, Zr, Ga, Cr and Ba are concentrated in the residual system; and Hf, Ta, Co, Rb, Cs, Be, and U are relatively immobile during the bauxitisation processes. The Nb, Th, Y, V, Sc, Sn and ΣREE are relatively immobile in the initial stage of bauxitisation processes in the bauxite ores, but were slightly mobile at the later stage of bauxitisation. Geochemical data reveal progressive enrichment of the REE and intense LREE/HREE fractionation toward the lower parts of the bauxite profile. Cerium behaves differently from the other REEs (especially LREE) and show positive anomalies in the upper horizons that gradually become negative in the deeper parts of the profile. The distribution and fractionation of trace elements and REEs during the bauxitisation process in the Bidgol deposit are mainly controlled by the presence of REE-bearing minerals, fluctuations in soil solution pH, REE ionization potential and the presence of bicarbonates or organic matter. Geochemical analyses confirm a protolith contribution from the bedrock argillaceous limestone and suggest that the source material for the Bidgol bauxite was provided from a siliciclastic material derived from a continental margin. The mid-Turonian uplift led to the formation of karstic topography, rubbly breccia and a layer of ferruginous–argillaceous debris that was affected by lateritic weathering under humid tropical climate. Subsequently, mobile elements are removed from the profiles, while Al, Fe and Ti are enriched, resulting in the formation of the pristine bauxite materials. When the platform subsided into the water again, the pristine bauxitic materials were partly converted to bauxite. During the exposure of bauxite orebodies on the limbs and crests of anticlines and subsequent eroding and accumulation in the karstic depressions during folding and faulting in Oligocene–Miocene, important factors such as intensity of the weathering, drainage and floating flow may have improved the qualities of the bauxite ores.

BACKGROUND: Teenagers are increasingly interested in computer games, and the adverse effects of these games are dependent on the execution of these games. The theory of planned behavior (TPB) is one of the most important theories in behavior change. This study aimed to determine the effect of educational planning based on TPB on the level of dependence on computer games in high school male students in Gonabad, Iran. MATERIALS AND METHODS: This was a randomized controlled trial. The study population was students of computer games in Gonabad. Sixty-four students were selected by a multistage random sampling method and were randomly divided into intervention (n = 32) and control (n = 32) groups. Data-gathering tool was the standard questionnaire of computer game dependency and researcher-made questionnaire according to TPB constructs that were completed before, immediately, and 3 months after the intervention. The intervention consisted of eight 90-min training sessions. Data were analyzed using the Chi-square test, Fisher's, t-test, repeated measures ANOVA, and Bonferroni post hoc test. RESULTS: Before the intervention, the intervention and control groups were matched for the mean score of model constructs. However, after the intervention, the mean score of computer game addiction significantly decreased (≤0.001). However, the mean score of knowledge, attitude, perceived behavioral control, and behavioral intention increased, which was statistically significant. Furthermore, the mean changes of model structures were statistically significant (P < 0.05). CONCLUSION: The findings revealed that TPB can be used as a good theoretical framework for designing and implementing educational programs to reduce the dependency of computer games on students.

The Mazra’eh Shadi deposit is one of the most representative gold deposits in the Ahar-Arasbaran Belt. The main minerals are galena, sphalerite, pyrite and chalcopyrite. Concentrations of Au-Ag occur mainly within quartz veins. Five textures (crustiform, comb, microcrystalline, cockade, and mosaic) are distinguished by field reconnaissance and hand specimen observations. The d 34 S values suggest an increasing role of meteoric water from the deepest levels to the shallow level and surface. Fluid inclusion data show that the mineralisation at the Mazra’eh Shadi deposit can be classified as a volcanic-rock-hosted intermediate-sulphidation epithermal deposit. Fluid inclusions in vein quartz can be distinctly divided into three types according to interpretation of petrographic features: intense boiling, gentle boiling and non-boiling conditions. The presence of intense and gentle boiling among different substages at the same level in the Mazra’eh Shadi deposit indicates that the base of the boiling zone likely shifted upward and downward during vein formation. The concentrations of Au-Ag occur mainly within quartz veins in the shallow level with gentle boiling (max. 813 ppb Au) and with intense boiling (max. 2420 ppb Au), whereas lower Au-Ag concentrations are associated with base metal-rich (Pb-Zn) in the deepest levels with non-boiling fluids (max. 52 ppb Au).

The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran), is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE) values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs) in general show higher concentrations than heavy REEs (HREEs) in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La–Nd), middle REEs (MREEs; Sm–Ho) and HREEs (Er–Lu) of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1) the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2) HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1) one that has La/Y >1 beingadjacent to the ore body and; 2) another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Yb)n, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

The Rangraz copper deposit (5 Mt @ 0.83% Cu) is located 20 km north of Saveh city, Markazi Province, Iran, in the central Uromieh-Dokhtar volcano-plutonic belt. Host rocks are mainly composed of Eocene volcanic and volcaniclastic rocks that have been intruded by late Eocene quartz monzodiorites and basaltic-andesitic dikes. The dominant copper-related hydrothermal alteration types include silicification, sericitization, and chloritization-kaolinitization. The ore body takes the form of fault-hosted, NW-SE-striking lodes comprising pyrite, chalcopyrite, bornite, specular hematite and magnetite as the principal hypogene ore minerals. Gold (maximum spot assays of up to ca. 0.37 ppm Au) and silver (up to 20.6 ppm Ag) have also been recorded. The ore minerals are mainly confined to veins or veinlets showing crustiform, colloform, open space-filling, dissemination and replacements characteristics in texture. The principal gangue minerals are quartz, barite and calcite. Most of the fluid inclusions identified in quartz-chalcopyrite ± specular hematite veins contain two liquid and vapour phases at room temperature. The primary and pseudo-secondary fluid inclusions have low to intermediate homogenization temperatures between 134 and 338 °C and salinities between 3.55 and 16.89 wt% NaCl equivalents. The fluid inclusion data are consistent with a two-stage evolution of the mineralizing system with initial metal precipitation at crustal depths of

The Lubin-Zardeh Au-Cu ± Pb ± Zn deposit is located in the Azerbaijan-Western Alborz zone, 45 km NE of Zanjan, Iran. It is situated within the Eocene-Oligocene volcanic-plutonic belt of the Tarom subzone of the Alborz mountains range. Quartz monzonite and tuffs are the main host rock of the Lubin-Zardeh Au-Cu ± Pb ± Zn deposit. Granitoid rocks are predominantly high- K, calc-alkaline with shoshonitic affinities. They are I-type, metaluminous, magnesian and are characterized by LILE, LREE and Th enrichment relative to HFSE, depletion in Nb, Ta, Ti and weak depletion in HREE and Y. These granitoids show some affinities with adakites, e.g., high Sr/Y and La/Yb ratios coupled with low Yb and Y, and enrichment in LREE and LILE with weak Eu anomalies. Their relatively low to moderate initial 87Sr/86Sr values (0.7047–0.7051), positive Nd (t = 36 Ma) values (0.39–2.1) and TDM ages of 0.69 to 1.06 Ga, with Pb isotopic ratios of initial 206Pb/204Pb = 18.49–18.68, initial 207Pb/204Pb = 15.58–15.61 and initial 208Pb/204Pb = 38.33–38.77, are consistent with a phlogopite-bearing, amphibole-rich, and enriched lithospheric mantle source metasomatized by earlier subducted sediments. The geochemical and isotopic compositions of the granitoids are similar to the host rocks of porphyry and epithermal deposits in the Urumieh–Dokhtar zone.

The Milajerd Pb-Zn ± Au polymetallic prospect in Naein-Qom Magmatic Zone is a favorable target for exploration. Geological and geochemical characteristics such as setting, alteration assemblages, fluid inclusion microthermometry and stable isotopes are consistent with the Milajerd Pb-Zn ± Au polymetallic prospect being a typical low-sulfidation (LS) epithermal deposits. The Au-polymetallic mineralization occurs mainly as structurally controlled veins, and brecciated dikes, hosted by calc-alkaline volcanic rocks. Mineralization at the Milajerd prospect is controlled by an annular fault system. The sulfide mineralogy of the deposit includes sphalerite, galena, pyrite, arsenopyrite, and marcasite. The principal gangue minerals are quartz, calcite, sericite, and adularia. The alteration assemblages include quartz ± pyrite, quartz-sericite-pyrite and chlorite-calcite-epidote. Fluid inclusions in quartz-sulfide veins have homogenization temperatures (Th) of 158–255 °C and salinities of 4.7–7.7 wt% NaCl equiv., whereas those in barren quartz ± carbonate veins yield Th values of 135–176 °C and salinities of 1.1–4.3 wt% NaCl equiv. The H and O isotopic composition (δDwater = − 120 to − 92‰; inferred δ18Owater = − 6.2 to 3.5‰) of fluid inclusions in quartz veins imply that cooling a mixed magmatic and meteoric waters was the main mechanisms of ore deposition at Milajerd deposit. The δ34S values of ore sulfides are mostly close to zero (avg. − 0.1‰), indicating a magmatic source of sulfur, which could have emanated directly from magmatic activity or have been leached from the surrounding volcanic rocks.

The Sarvian Fe skarn deposit is located in the Urumieh–Dokhtar magmatic arc, western Iran. The Sarvian quartz diorite intruded the surrounding Permian to Tertiary limy formation, culminated in thermal metamorphism as well as skarnification in which the Sarvian deposit formed. Microthermometry studies in the Sarvian skarn deposit reveal two distinct inclusion groups; group A with medium–high temperature and hypersaline and group B with low–medium temperature and low salinity. Group A inclusions which are entrapped during formation of prograde are thought to be derived from the magmatic source. Fluid boiling and subsequent developing of hydraulic fracturing led to inflow and/or mixing of early magmatic fluids (group A) with circulating groundwater culminated in formation of low salinity and low temperature fluid inclusions (group B) during the formation of retrograde assemblage. Fluid inclusion thermometry reveals the formation temperature and the salinity of 300–370 °C and 31–33 wt% NaCl for the prograde stage and 180–230 °C and 1–15 wt% NaCl for the retrograde stage of skarnification at Sarvian skarn rocks. Fe-mineralization as well as hydrothermal minerals occurred during retrograde metasomatism. The estimated depth and pressure of occurrence for prograde stage are 1000–1200 m and 100–150 bars, and for retrograde stage, these are about 200 m and 50 bars, respectively. Garnet and pyroxene, as the main constituent minerals of prograde stage, are the most informative minerals offering a suitable tool to constrain the skarnification conditions. Garnets in the Sarvian deposit are mainly grossular and andradite, showing both normal and inverse zoning as the result of variation in their chemical composition. Such types of zoning represent alternation of high acidity oxidation and low acidity oxidation conditions that were prevailed on skarnification in the Sarvian prograde assemblage. Also, chemical composition of the Sarvian pyroxenes shows an alternation of high oxygen fugacity and low oxygen fugacity conditions for their formation. This is also supported by fluctuation of the ratios of andradite to grossular and diopside to hedenbergite, denoting to an obvious shifting that was prevailed between oxidizing and redox conditions during formation of prograde assemblage in the Sarvian. Garnet–pyroxene thermometry determines the formation temperature of prograde assemblage between 370 and 550 °C at Sarvian skarn rocks which is verified also by fluid inclusion thermometry. Decomposition of limestone by reaction of high-temperature hydrothermal fluids with carbonate host rock resulted in injection of CO2 into the Sarvian system that caused oxidation, changing Fe+2 to Fe+3 culminated in the magnetite deposition.

The Sar-Faryab bauxite deposit is located in 250 km east of Ahvaz city in southwestern Iran. Structurally the deposit located in the Zagros Simply Folded Mountain Belt. Outcrops of the bauxite horizons in the area are distributed irregularly over an area of about 20 km 2 but have fairly uniform thickness averaging 1 to 1.5 m. The Sar-Faryab bauxite is situated in NW–SE trending Mandan anticline and occurs in karst horizons near or at the boundary between the Sarvak and Ilam Formations. Based on field observation, mineralogy and stratigraphy an unconformity during Cenomanian–Turonian times has exposed the Sarvak Limestone to karst weathering and the layers of Marly Limestone, Argillite, Oolitic–Pisolitic, Yellow, Red and White Bauxite were formed and accumulated in the karstic areas. This study uses the geochemistry of immobile elements to trace the precursor rock of the bauxite deposit and to calculate the mass changes that took place during weathering and bauxitization. In this way fifteen samples were collected from seven layers of the deposit for geochemical studies using XRF. Geochemical data show that Al and Ti were immobile during the bauxitization process and were used for mass change calculations. Mass changes were calculated from the concentration ratio of immobile elements for the different bauxite rocks and the Sarvak Limestone. As only one linear trend is evident in the Al–Ti binary diagram and the Sarvak Limestone coincides with this trend, we concluded that the source of the Sar-Faryab bauxite was the underlying Marly limestone (Sarvak Formation). The karst bauxite deposits are probably of authigenic origin, as evidenced by their geochemical characteristics, lithologic associations, textural and mineralogy.

The Almoughlagh batholith intruded the dioritic Baba Ali pluton during the Oligo-Miocene; the pluton and is now exposed as a big enclave within the batholith. The pluton intruded the Songhor Series during the Late Kimmeridgian (~136 Ma) orogeny. The intrusion by the batholith transformed the diorite to metadiorite and the impure carbonate units of the Songhor Series. The batholith consists of rock types such as quartz syenite and syenogranite, which have a low average quartz content, and which are metaluminous to peraluminous and calc-alkaline in composition. Comparison of the compositions of the Almoughlagh batholith and the pluton with its Cu, Mo, Fe, Sn, W, Au, and Zn skarn deposits, indicates that the Baba Ali diorite geochemically shows much resemblance with those which could bring about Fe-Cu skarn mineralization, whereas the compositions of the Almoughlagh granitoids resembles those of the plutons associated with Mo and Zn skarn deposits. The associated hydrothermal activity related to the Almoughlagh batholith culminated in magnetite mineralisation in the Baba Ali and the Chenar mines in which copper mineralisation also is considerable.