List of Articles Mineral chemistry

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  1 - Clinopyroxene mineral chemistry of Peshtasar basalts, sedimentary basin of Moghan (NW Iran)
  AbbasAli Amrei Reza Zarei Mohsen Moayyed Ahmad Ahmadi AmirMorteza Azimzadeh
  With the east–west exposure trend, Peshtasar basalts are in the sedimentary basin of Moghan (Talesh structural zone), in the northwest of Iran.The Peshtasar complex lithologically includes basalt, andesitic basalt or basaltic andesite, megaporphyric andesite, leucite te More

  With the east–west exposure trend, Peshtasar basalts are in the sedimentary basin of Moghan (Talesh structural zone), in the northwest of Iran.The Peshtasar complex lithologically includes basalt, andesitic basalt or basaltic andesite, megaporphyric andesite, leucite tephrite and volcanic breccia. The main constituent minerals are plagioclase, clinopyroxene, and iddingsitized olivine in basalts and plagioclase megacryst, clinopyroxene, and leucite in tephrite. The results of the microprobe analyses of clinopyroxene reveal the diopside composition. Clinopyroxenes of Peshtasar basalts have igneous nature originated from alkaline and continental magmatic serries. The results of termobarometry studies indicate the crystallization range from 800 -1200 degrees centigrade and crystallization pressure less than 5 kb. There was no water in composition of the parent magma of these rocks. The titanium contents of clinopyroxenes were low, indicating the presence of titano-magnetite (opaque minerals) in the rock. The ferric iron values in clinopyroxenes represents a high oxygen fugacity of magma. Manuscript profile
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  2 - Physicochemical properties and tectonic setting of the basic intrusive rocks from south of the Germi (Ardabil): based on amphibole and plagioclase crystals chemistry
  Mohammad  GholamReza Ahmadzadeh elham aghazadeh
  Eocene- Oligocene intrusive stock of basic bodies of south Germi are intruded into and cropped out in Eocene basaltic lavas. Studied gabroic intrusive rocks generally show granular texture with assemblages characterized by Cpx + Pl + Bi + Amph. Pyroxenes have augitic co More

  Eocene- Oligocene intrusive stock of basic bodies of south Germi are intruded into and cropped out in Eocene basaltic lavas. Studied gabroic intrusive rocks generally show granular texture with assemblages characterized by Cpx + Pl + Bi + Amph. Pyroxenes have augitic composition, plagioclase have labradoritic and amphiboles have pargasitic compositions. The studied amphiboles show (Na+K)A ≥ 0.5 with variable amount (0.57 - 0.99), Fe+3 content ranges from 0.00 to 1.17, also AlVI ranges from 0.00 to 0.68 and AlVI<Fe+3. Chemical composition of amphibole can be used in determination of magma genesis. Results of thermobarometric studies indicate that the amphiboles formed at temperature range of 750oC -885 oC and pressure range of 5.96 – 8.36 Kb, that coincide with depth of 18.5 – 25.9 km. Also using the amphiboles and coexisting plagioclases thermometer shows temperature range from 758 oC to 865oC. Chemical composition of amphibole minerals with Fe2+/(Fe2++Mg) ratio from 0.11 to 0.32, variable oxygen fugacity (-5.83 - -6.34) and water content (3.09 – 4.16%) shows that they formed from sub-alkaline magma. Chemical studies of amphibole crystals indicate that they formed during a subduction related magmatic activity. Manuscript profile
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  3 - The Study of mineral chemistry, tectonomagmatic setting and petrogenesis of plutonic bodies in Sursat Complex, NW Takab, Iran
  Soraya Dadfar Farhad Aliani Ali Akbar Baharifar Mohamad Hossian Zarinkoub
  The plutonic bodies occurring in Sursat complex are some parts of plutonic rocks of Sanandaj- Sirjan Zone. Based on the field observations and microscopic studies, rocks of the study area are consist of hornblende gabbro, quartz diorite, monzodiorite, granodiorite and t More

  The plutonic bodies occurring in Sursat complex are some parts of plutonic rocks of Sanandaj- Sirjan Zone. Based on the field observations and microscopic studies, rocks of the study area are consist of hornblende gabbro, quartz diorite, monzodiorite, granodiorite and tonalite. The EPMA analyses of minerals such as amphiboles (in granodiorite and monzodiorite), plagioclases and alkali feldspars indicate that amphiboles are magnesiohornblende, plagioclases are albite and oligoclase and alkali feldspares are orthoclase. Geochemical studies indicate that monzodiorite unit (Turke Dare and Khangholi bodies) are metaluminous I-type and calc-alkaline in nature. They are plotted in volcanic arc granite (VAG) region with 87Sr/86Sr and εNd values equal to 0.70448 and -0.12. All evidence represent that the monzodiorite were generated from a magma which was derived from mantle affected by assimilation and contamination processes. Granodiorite unit (Pichaghci, Hamzeh Ghasem and Northeast Khangholi bodies) represents I-type, metaluminous to peraluminous and calc-alkaline characteristics and is plotted in VGA field of magmatic arc. The 87Sr/86Sr and εNd values are equal to 0.70529 and -2.82 respectively. So these granodiorites were generated through mixing processes of a mantle magma with crustal sources. Tonalite–trondhjemites group are I-type, tholeiitic, peraluminous according to the low value of Mg# (2.9-11.6), Cr (20-46 ppm) and Ni (1-2.4 ppm) contents. They are also low in LA/Yb, Sr/Y, and Nb/Ta. The slight negative anomaly in fractionated patterns of the rare earth elements (REE) and very low depletion in Eu, indicate that these rocks were resulted from amphibolitic crustal source that were previousely generated from thickened mafic crust or from basaltic plate in low pressures at shallow depth in the presence of abundant plagioclase. Manuscript profile
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  4 - The study of geochemical behavior of major and rare earth elements of garnet in the metamorphic rocks at Boroujerd area (Sanandaj-Sirjan Zone)
  فرشته  سجادی Somaye Rahmani NASIM Shamsaddini Zahra Tahmasbi   Hashemi Xink Ding Ahmad Ahmadi Khalagi
  Garnet–mica schist and hornfels rock units are exposed in the east and southeast of Boroujerd. These rocks consist primarily of quartz, K-feldspar, plagioclase, garnet (almandine–spessartine), chlorite, cordierite, andalusite, sillimanite, biotite, muscovite, and minor More

  Garnet–mica schist and hornfels rock units are exposed in the east and southeast of Boroujerd. These rocks consist primarily of quartz, K-feldspar, plagioclase, garnet (almandine–spessartine), chlorite, cordierite, andalusite, sillimanite, biotite, muscovite, and minor amounts of apatite, iron oxides (ilmenite and magnetite), and zircon. Whole-rock geochemical analyses reveal that the dominant protoliths are pelitic rocks. Major and trace element compositions suggest that the Boroujerd pelites were deposited along an active continental margin. Garnet porphryblasts in some hornfels samples are compositionally homogeneous with respect to major, trace and rare earth elements; this is attributed to the diffusional re-equilibration at high temperatures (>600 ºC). Garnet in schists and some hornfels samples show reverse compositional zoning with increasing Mn and decreasing Fe and Mg from core to rim. Higher concentrations of Mn in garnet rims are attributed to resorption during retrogression. The presence of chlorite around garnet porphryblasts in these schists also supports resorption during retrogression. In schists, concentrations of HREE and Y in garnet decrease from core to rim. These zoning patterns are interpreted to record garnet growth in a closed system (i.e., Rayleigh fractionation of compatible elements). Core–rim variations in the concentrations of trace elements and rare earth elements in garnet in the hornfels samples is negligible. The lack of prominent zoning of these elements in garnet from hornfels is interpreted as minimal fractionation due to rapid garnet growth. Manuscript profile
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  5 - Study of mineral chemistry, geothermobarometry and tectonic setting of gabbroic rocks from north-west Hamedan, Iran
  عادل ساکی Hooshang Pourkaseb Alireza Zarasvandi Milad Jahani Maryam Dorani
  The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and More

  The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and zircon. The obtained results from the mineral chemistry in this study indicate that the amphiboles are calcic amphiboles, and in terms of chemical composition they can be called pargasit, tschermakite and magnesiohomblende. Plagioclases are also andesian. Due to the low Na2O content, it can be concluded, that tectonically these amphiboles are of S-Amph type and are related to the subduction zones. Based on the high levels of Al2O3, the origin of amphiboles is mantle-type. Therefore, due to the ratio of Fetot (Fetot + Mg+2) to AlIv, which is less than 0.6, the oxygen fugacity was high. On the other hand, the water levels vary from 2 to 2.3 for hornblende crystallization. Different methods were used to perform thermobarometry, the best of which showed that the formation temperature of gabbroic mass has been in the range of 700°C (in average) and a pressure of 4.45- 7.52 Kb. According to the estimated pressures, the magma was originated at a depth of 25-30 Km, which is near the Moho discontinuity. Manuscript profile
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  6 - Mineral chemistry and thermodynamics conditions of impure marbles formation from Neybaghi metamorphic complex, NE of Myaneh, Iran
  Javad Izadyar
  A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textura More

  A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textural and mineralogical evidences, revealed two metamorphic stages. The early stage is testified by the minerals such as pyroxene (diopside), epidote (clinozoisite), amphibole 1 (edenite-pargasite) and plagioclase 1. The main stage have chlorite (clinochlore), phlogopite, amphibole 2 (tremolite) and plagioclase 2. P-T-XCO2 have been estimated for the early and main stage of metamorphism by computing nonideal and asymmetrical fugacity and activity and programing in THERMOCALC software for fluid and solid phases. The estimations give pressure, temperature and XCO2 of 9.5Kbar, 660°C and 0.35, whereas the main stage has been constrained at P=4.2Kbar, T=510°C, XCO2=0.4. The obtained P-T path shows that the Neybaghi marbles were formed under medium pressure condition and overprinted by a low pressure metamorphism. This type of P-T trend can be formed in collisional tectonic regime. Manuscript profile
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  7 - Mineralogy and mineral chemistry of Pb- Ag- (Zn-Cu-Ba) Ravanj mining district, North of Delijan
  Majid Ghasemi siani Fateme Isaabadi
  The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies con More

  The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies consisting of galena, sphalerite, fahlore group minerals, pyrite, chalcopyrite, dolomite, calcite, ankerite, barite, and quartz. Sulfide ore mineralization occurred within two mineralization horizons consisting of the massive-breccia ore horizon hosted by massive upper limestone (Km2) and layered sulfide ore horizon in middle shale (Ks2) and lower thin bedded limestone (Km1) as syn-sedimentary to epigenetic mineralization. Dolomitization is the main alteration related to mineralization and occurs adjacent to normal fault and consists of diagenetic and two hydrothermal dolomites. Hydrothermal dolomites are rich in iron. The ankrite shows that the ore hydrothermal fluid was Fe-rich. Chemistry of galena II and sphalerite II show that these minerals have a tendency to tetrahedrite-tennantite side which are consistent with presence of fahlore mineral incluisions in the microscopic studies. High Cd content in sphalerite and the presence of acanthite show that fluid mineralization had low temperature. According to the evidence such as mineralogy, mineral chemistry, ore texture and structures, and structural studies and combining these results with geochemistry, fluid inclusion and isotope geochemistry, the Ravanj ore deposit can be considered as an Irish-type Zn- Pb deposit. Manuscript profile
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  8 - Mineral chemistry of clinopyroxene, an approach to petrogenesis of Saray Volcanic Complex–Northwest of Iran
  M.  Ghaderi N. Amel M. Moayyed
  Saray volcano is an extinct volcano and is located in the east of Urmia Lake. This volcano mainly consists of Leucititic lava flows and their related pyroclastic materials forming a Sequence which repeated more than five times. Leucite phonolitic dykes, Lamprophyric (Mi More

  Saray volcano is an extinct volcano and is located in the east of Urmia Lake. This volcano mainly consists of Leucititic lava flows and their related pyroclastic materials forming a Sequence which repeated more than five times. Leucite phonolitic dykes, Lamprophyric (Minette, Monchiquite and Spessartite) lavas and dykes, Trachytic domes and dykes, Syenitic dykes and a small syenitic stock are other rock types of Saray volcano. Since clinopyroxene is present in all rock types of this volcano, mineral chemistry study of clinopyroxenes in all rock types of Saray volcano, could help us to explain the relationship between different rock types. Clinopyroxenes of Saray volcano have diopside, salite and fassaite compositions. The majority of studied clinopyroxenes crystallize under 3-4 kb pressure and 1150 centigrade temperature. Tectono-magmatically speaking, these clinopyroxenes were mostly formed within plate basalts. Although the composition of rock types of Saray volcano is very different, almost constant composition of clinopyroxene in all rock types, show the same origin for all clinopyroxenes. However, it can be concluded that all rock types have the same origin. Manuscript profile
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  9 - Geochemistry and Mineral Chemistry of the Ahowan intrusion rocks, northeast Semnan (Central Iran)
  Saeed  Kamran Ahmad Ahmadi Khalaji M. Rezaei-Kahkhaei Zahra Tahmasbi
  The study rocks outcropped in the northeast Semnan area. These rocks, composed of monzogabbro-monzodiorite, was intruded in the Eocene sedimentary and volcanic rocks. Plagioclase and clinopyroxene are the main constituent minerals of these rocks. The study rocks represe More

  The study rocks outcropped in the northeast Semnan area. These rocks, composed of monzogabbro-monzodiorite, was intruded in the Eocene sedimentary and volcanic rocks. Plagioclase and clinopyroxene are the main constituent minerals of these rocks. The study rocks represent granular and poiiklitic textures. Based on EMPA data, clinopyroxenes, and plagioclases are diopside and augite and andesine, labradorite and bitonite in compositions and formed in temperatures ranged from 1104 to 1168 and less than 700 °C respectively. On the basis of tectonic discrimination diagrams, the investigated samples fall into volcanic arc domain resulted in subduction of Neothetian oceanic lithosphere beneath Central Iran block. Manuscript profile