مجله بلور شناسی و کانی شناسی ایران
سال سی و یکم شماره 2 (پیاپی 92، تابستان 1402)

The Dumak ophiolitic mélange in the Baluchistan region is one of the ophiolitic mélanges that contains all of the components of a complete ophiolite, located in the middle parts of the western margin of the Eastern Iranian range. Field studies indicate the presence of a large volume of pillow lavas in different parts of the Dumak mélange. The outcrop of sheeted dikes associated with the Dumak mélange is limited to the Shuru region. These dikes present below the pillow lava and Cretaceous pelagic sediments. Compositionaly, most of pillow lavas and sheeted dikes are basalt. Variations in SiO2 to FeOt/MgO in the pillow lavas and sheeted dikes indicates a tholeiitic trend for their productive magma. The pattern of REE elements and amounts of (La/Sm)N in these rocks are similar to E-MORB. The study of pillow lavas and sheeted dykes of Dumak ophiolitic mélange shows that the MORB ophiolitic body in Dumak has been gradually and continuously evolved in a supra-subduction zone environment and beginning of intra-oceanic subduction. Considering structural evidence of the region, after adding the Dumak ophiolite to the Lut block, during the continuation of tectonic movements related to orocline bending, a new mélange has formed with the presence of Eocene carbonate blocks.

Dalfard granitoid complex is located in the southeast of Kerman Province between  57˚ 30 ˊ to 57° 45 longitudes and 28˚ 55ˊ to 29˚ 10 ˊ latitudes. This granitoide complex contains granite, granodiorite, quartz-diorite, diorite, in the margins, and is mainly composed of quartz-diorite. The main texture is granular and include quartz, plagioclase, amphibole, biotite and alkali-feldspar, with some mafic microgranular enclaves in them. The EMPA data showed that plagioclase are andesine and alkali-feldspar with orthoclase composition. Biotites with Fe/Fe+Mg > 3.3 rato fall in the magnesium-rich biotites area. Amphiboles are calcium type and they have magnesiohornblende in composition, which indicates that their host magmas are I-type. The low values of Na2O in amphiboles, their calc-alkaline nature, and the high oxygen fugacity indicate that they belong to the subduction environment and mantle derived magmas along with the crustal compounds contributed to the formation of their host magmas. Geo-thermo-barometry calculations estimate the average crystallization pressure of 1.4 kb and temperature of 681 °C for the studied hornblende.

The Chah Mileh Pb-Zn (-Cu) deposit is located in the Yazd-Anarak metallogenic belt, Central Iran. Primary sulfide mineralization (e.g., galena, sphalerite, chalcopyrite and pyrite) formed within dolomitic marble unit of the Middle Triassic Chah Gorbeh complex. Mineral matter often occurs as, brecciaed, open-space filling, disseminated and replacement textures. The non-sulfide ore of the Chah Mileh deposit were formed by supergene oxidation of primary sulfide minerals during the complex interplay of tectonic uplift, karst development, changes in the water table, and weathering. Cerussite, hemimorphite, wulfenite, mimetite, smithsonite, malachite and iron oxy-hydroxides are the most non-sulfide ore minerals in the Chah Mileh deposit. In Chah Mileh deposit, the oxidation of pyrite and similar sulphides led to supply of sulphuric acid which resulting low-pH values and increasing PCO2 due to acid-neutralisation by host-rock carbonates; therefore liberation of sulphate ions and precipitation of iron oxy-hydroxides play an important role in the formation of non-sulphide ore. Under acidic conditions most of the zinc leaves the oxidation zone and precipitates as zinc carbonates (e.g., smithsonite and less hydrozincite, based on PCO2 values) in adjacent to the carbonate host rock, while most of the lead within the oxidation zone precipitates as cerussite and adsorbed by feoxyhydroxides. Based on geological, textural and mineralogical composition, the non-sulfide ore of the Chah Mileh belongs to supergene non-sulfide deposits and subtype of direct replacement deposits (red ore).

Kuh-Rakhneh  district is located in the southwest of Qaleh Zari mine in Birjand city and in the central part of Lut block. The geology of the area includes the alternation of volcanic rocks with dacite to andesite composition and subvolcanic units involving granodiorite porphyry, tonalite porphyry, pyroxene diorite porphyry, diorite porphyry, and quartz diorite porphyry that have penetrated them. The alteration zones in the study area include propylitic-chlorite, sericite, argillic, silicification, and carbonate that silicification and argillic alterations are closely related to the mineralization process. Mineralization has occurred in the form of three main veins (A, B, and C) with a southeast-northwest trend within fault zones in andesitic and diorite rocks. Primary ores include pyrite, chalcopyrite, and secondary ores include bornite, chalcocite, covellite, and malachite. Mineralization in these veins is also created in the form of veins, masses, replacement, and breccia.The chemical composition of these I-type subvolcanic intrusions are between predominantly metaaluminous to slightly peraluminous with calc-alkaline characteristics. Also, negative Eu anomalies and a ratio of less than one (Eu/Eu*=0.54-0.96) indicate the presence of plagioclase in the origin of magma. The low amount ​​of Nb and Ti in these units reveals formation at tectonic setting associated with the subduction zone in the active continental margin. Based on geochemical analysis, trace and rare earth elements, the magma source that forms these subvolcanic units had been generated from  1 to 5% partial melting of garnet spinel lherzolite in the enriched mantle and at the depth of about 65 to 67 km.

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 Chomalu ore deposit is located in the western part of the Alborz magmatic belt (Alborz-Azerbaijan) and geology includes Lower Eocene volcanic to volcanoclastic, including olivine basalt, andesite basalt, andesite to trachyandesite, dacite to rhyolite, and Upper Eocene granitoids including quartz monzonite to quartz monzodiorite. Ore formation in the Chomalu deposit is hosted by olivine basalt and andesite to trachyandesite rocks. The main ore minerals at Chomalu deposit consist of galena, sphalerite, tetrahedrite, pyrite, chalcopyrite, and magnetite. Quartz and fluorite are the main gangue minerals in the Chomalu deposit. Ore mineralization occur as veins and open space filling textures. Field observation shows that mineralization occurred in E-W and NW-SE trending quartz veins. Three mineralization stages were recognized at Chomalu deposit. The geochemical studies show high correlation coefficient indexes between Pb -Zn, Pb-Ag and Cu-Pb and Zn. Vein-veinlets, open space filling and colloform textures; galena, Fe-poor sphalerite, tetrahedrite, pyrite and chalcopyrite mineralization; relatively high base metal sulfides (e.g., Cu, Pb, and Zn); gangue minerals including quartz, fluorite and minor calcite, mineralization with olivine basalt and andesite to trachyandesite as host rocks show that Chomalu mineralization can be classified as IS epithermal deposit.

Along Toveireh Fault, in the northwest of Central-East Iranian Microcontinent, the Oligocene alkali-basalt outcrop was investigated for petrography and mineral chemistry. They include phenocrystals of chrysolite (Fo70–90), augite-diopside (Mg#=0.82) and labradorite (An30-70) in a fine-grained matrix of the same minerals as pheoncrysts, together with sanidine and secondary minerals (serpentine and zeolite), as well as opaque minerals. These rocks contain sillimanitite xenoliths which are mostly composed of fibrous and prismatic sillimanites, together with minor amount of corundum, and secondary minerals (chlorite and scapolite). Xenoliths show granoblastic, nematoblastic, poikiloblastic, and corona textures. These high-Al and moderately silica-rich xenoliths were probably formed by metamorphism of continental crust sedimentary rocks, conveyed up to the earth's surface by ascending alkali basalt magma. Fibrolite formation around some of the prismatic sillimanits and Al-rich spinels (Mg#=0.4-0.5) formation in the contact of xenolith and host basalt indicate that pressure-temperature decreased during magma ascending and reaction of basaltic magma with xenolith.

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).

Amir Abad prospect area is located in northwestern Neyshabur, Khorasan Razavi Province. Geology of the area includes post-Eocene subvolcanic igneous (diorite porphyry), Paleogene volcanic (andesite) and sedimentary (sandstone and conglomerate) units. Sedimentary units of the area consist of layers of oxidized red sandstone, gray sandstone and conglomerate. Sandstones deposited in a continental to oceanic island arc tectonic setting within sedimentary basin. Copper mineralization, as layer and lens (syndiagenetic), occurs in sections with mostly lithic arenite composition (coarse grain) and abundant plant fossil. Primary minerals (with disseminated, veinlet and replacement textures) include pyrite and chalcocite, which during secondary stages chalcocite, covellite, malachite, hematite and goethite were formed. Maximum geochemical anomalies in the horizons of mineralization for copper, silver, and zinc are %6, 14 ppm and 99 ppm respectively.. Based on type of host rock, sulfide minerals, texture and mineralization controlling agen (presence of plant traces as reducing factor and host rock permeability), mineralization type is similar to sedimentary copper deposits of Red Bed type.

The study area is located in northeast Iran, about 10 Km southwest of Khaf city. Geology of the area includes the Upper Eocene sedimentary (conglomerate), volcanic (basalt, andesite, dacite) and pyroclastic (ignimbrite) rocks. The basalt unit displays porphyritic, glomeroporphyry, vitric, sieve and amygdaloidal textures. The minerals are mainly plagioclase, pyroxene, hornblende and olivine. The andesite unit has porphyry, with microlitic groundmass, vitric, glomeroporphyry and sieve, textures. The minerals mainly consist of plagioclase, hornblende, and K-feldspar. The dacite unit has porphyry texture and consists of plagioclase and quartz minerals with lesser amounts of K-feldspar. Volcanic units of Gorazi have characteristic of Calc-alkalic to high-K Calc-alkalic. Enrichment of LREE relative to HREE and LILE to HFSE are important evidences that magma was formed in a magmatic belt of a subduction zone. Based on geochemical data, the volcanic rocks are originated within the enriched mantle source and, among subduction components, metasomatism related to sediments has played the most important role.

The Faryab ophiolitic complex is located in Golashkard region, in the southeastern part of Sanandaj-Sirjan zone. This complex is mainly composed of the ophiolitic mantle part consisting of dunite, wehrlite, and pyroxenite, as well as chromitite and serpentinite, which was thrusted on the metamorphic rocks of the Bajgan complex. Dunites are found in the form of bodies sometimes containing thin layers of chromitite. Wehrlite and pyroxenite are also exposed as minor dykes in different parts of the complex. The main texture in the wehrlite and dunite is granular and cataclastics. The chromitites appear in both stratiform and podiform. Microscopic evidence indicates that the presence of lattice preferred orientation in minerals may be formed during recrystallization at high- temperature mantle. The chemistry of minerals in the peridotites shows that rocks including forsterite with low chromium and high nickel, diopside and magnesium-bearing Cr-spinel with small amounts of orthopyroxene were partially melted in the upper mantle up to 35 to 40%. Using tectonic setting discrimination diagrams led us to conclude that the Faryab complex peridotites are a part of the oceanic lithosphere which have emplaced in the supra-subduction zone, suffered partial melting evolutions and then tectonically emplaced in the crust in the form of ophiolitic remnants.

Chlorite group minerals have a wide range of chemical composition that reflect their physical and chemical conditions of crystallization. In this research, the chlorite mineral geothermometry method has been used to determine the alteration temperature of delay dykes in Sungun copper-molybdenum porphyritic deposit, located in the northwest Iran. Based on the microprobe data, the compositional changes of chlorite reflect a large differences in the content of silicon, aluminum, iron and magnesium elements in these dykes. The chemical composition of the chlorites in quartz diorite porphyry (DK1a, DK1b), diorite porphyry (DK3) and microdioritic (MDI) dykes placed in picnochlorite range of type clinochlor and quartz- dioritic dykes (DK1c) are in the penin range type of chamosite. Chlorite in quartz diorite porphyry (DK1a, DK1b, and DK1c) and diorite porphyry (DK3) dykes enrichment in the Mg-chlorite and microdioritic (MDI) dykes enrichment in the Fe-chlorite and are classified as trioctahedral chlorites. According to different geothermometric methods, chlorite minerals in quartz diorite porphyry (DK1a, DK1b, and DK1c), diorite porphyry (DK3) and microdioritic (MDI) dykes, have formed at temperatures of 237°C, 217°C, 115°C, 276°C and 247 °C respectively. These temperatures show the effect of hydrothermal fluids in the formation of chlorite and show that the chlorites of the studied area can be related to the effect of hot fluids originating from magma. The relationships between the SiO2 content and the crystallization temperature in Sungun late dykes show an inverse and strong correlation; so that high temperature chlorites in these dykes have lower Si content than chlorites crystallized at low temperatures. Therefore, the silica chlorite content of these dykes can be an indicator of their crystallization temperature. Chlorites have specific compositional changes and atomic substitutions that reflect their crystallization temperature.

In this research, the bismuth ferrite (BiFeO3) nanostructure doped with Cu was prepared by a sol-gel method at a temperature of 650 ºC in a period of 60 minutes. First, bismuth ferrite nanoparticles are provided, then its doping with Cu (BiFe1-yCuyO3) with y = 0.0, 0.05, 0.10 ,0.15 ,0.20, 0.25, and 0.30 has been done.  The structural properties of the samples have been characterized using the XRD, FESEM, FT-IR, and EDX. Investigations of the structural properties showed that as increasing Cu, the content of ferrite bismuth phase decreases and the secondary phases such as Bi2O3 ، Bi2CuO4 and Bi2Fe4O9 have increased. The magnetic and dielectric properties of the samples using the analyses of VSM, and LCR meter have been investigated. Investigations of the magnetic properties showed that as increasing Cu, the magnetic properties of the samples improved. The dielectric constant and the dielectric loss of the samples decrease with increasing frequency, which indicates the natural dielectric behavior of bismuth ferrite.

Nowadays, the use of diamond-like carbon films has been considered for industrial and biological applications, so in today's research, by introducing impurities (metallic or non-metallic), they are looking for new structural and mechanical properties. Therefore, this research discussed the fabrication and characterization of silver nanoparticles in a diamond-like carbon (DLC) thin film bed on various metal substrates using the simultaneous radio frequency plasma sputtering and chemical vapour deposition method. Therefore, the films were fabricated from the silver target in an environment of a combination of acetylene and nitrogen gases at different working pressures. The morphology of the film was examined using an atomic force microscope (AFM) according to the standard 25178-2: 2012, and the statistical results obtained from the AFM data showed that the surface topography of the film at different pressures changed according to the substrate nature so that the samples prepared at a working pressure of 18.5 mTorr had the highest surface roughness compared to other samples. After that, the fractal properties of the prepared films were theoretically checked, and all the films have multi-fractal properties—the results of the multi-fractal analysis of the film satisfactorily complied with other AFM statistical data. Moreover, with the help of EDS and Raman analysis, the structure formation, the presence of carbon, nitrogen, and silver elements, and the existence of a carbon-like structure were confirmed.