List of Articles زنجان

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  1 - Petrography and investigations on relation between deformation and metamorphism in metapelites of the Kuhe Arqoon, west of the Anguran lead-zinc mine, Zanjan Province
     Moazzen  Izadyar
  The study area is located in the West of Anguran lead-zinc mine in Zanjan province, in the central Iran zone. The metamorphic rocks of the area include chlorite schist, epidote-amphibole schist, mica schist, marble, quartzite and metamorphosed gabbrodiorite. Metapelites More

  The study area is located in the West of Anguran lead-zinc mine in Zanjan province, in the central Iran zone. The metamorphic rocks of the area include chlorite schist, epidote-amphibole schist, mica schist, marble, quartzite and metamorphosed gabbrodiorite. Metapelites are the focus of the present study, since they have recorded mineral appearances and deformational phases due to suitable composition. Petrographic studies show that three types of metapelites, including biotite schist, garnet schist and muscovite schist are present. Retrograde metamorphisms, owing to pressure and temperature decrease during exhumation are recorded in the Kuhe Arqoon rocks. The main deformational features include andaluse extinction, mineral stretching, pressure shadow and preferred orientation of minerals. Using petrographical studies and considering relation between structures and porphyroblasts and matrix (microstructures), three main deformational phases were determined for the area, among them the second deformational phase was the strongest. This deformation has produced the main foliation in the rocks. The weakest phase was the third deformational phase, which was not accompanied by metamorphism. Contemporarily with D1 deformational phase, M1 metamorphic phase occurred, crystallizing chlorite, muscovite, quartz, biotite and garnet. M2 metamorphic phase was coeval with D2 deformational phase. Mineral assemblage of M2 is biotite, muscovite, quartz and garnet. During the weak D3 deformational phase, chlorite is formed with weak orientation in the rocks. Manuscript profile
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  2 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
           
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  3 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
    Afshin  Zohdi Hossein Kouhestani    
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  4 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
  Mahsa Noori
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  5 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
   
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  6 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
    Afshin  Zohdi Hossin Kohestani Ghsem Nabatian Mir Ali Asghar Mokhtari
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  7 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
    Afshin  Zohdi Hossein Kohestani Ghasem Nabatian Mirali Mokhtari
  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

  The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile
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  8 - The carbonate hosted epithermal gold mineralization in the Kavand, Southwest of Zanjan
  Nadia Partak Masoud Alipour-Asll
  The Kavand area is located in the southwest of Zanjan, in Soltanieh district in Central Iran zone. Mineralization is hosted by upper Precambrian-lower Cambrian sedimentary sequences, and it is mainly associated with the dolomitic rocks of the Soltanieh Formation. Minera More

  The Kavand area is located in the southwest of Zanjan, in Soltanieh district in Central Iran zone. Mineralization is hosted by upper Precambrian-lower Cambrian sedimentary sequences, and it is mainly associated with the dolomitic rocks of the Soltanieh Formation. Mineralization appears as massive, vein-veinlets and karst open space filling. Dominant alterations include iron-oxide, carbonate and silicic types. The ore minerals conist of hematite, specularite, gold, chalcopyrite pyrite, chalcocite, covellite, malachite, azurite, goethite and limonite, while quartz, barite, calcite and dolomite are gangue minerals. The Fe and Au are important ore-forming elements in this area. The average content of Fe and Au in the Kavand mineralization is 15.7% (Max. 28.4%) and 1.3 ppm (max. 14.6 ppm), respectively. Geochemical data represent a high positive correlation between Au with Ag, As, Sb, Cu, Zn, Cd, and Ba. Fluid inclusion studies on quartz from samples with quartz+sulfide+gold and iron oxides+barite+quartz+gold mineral associations indicate that average temperature was 277.84 ºC and salinity was 3.67 wt. % NaCl. Mineralization is likely formed under pressures below than 200 bars and a depth over than 700 m. The multi-element microprobe analyses of gold grains from stream sediments demonstrate that Au and Ag contents are dominant in the composition of Kavand gold index. The chemical composition of the Kavand gold particles compared with those from various gold deposits proves their epithermal source. The Kavand mineralization can be considered as a carbonate rock-hosted epithermal gold deposit. Manuscript profile
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  9 - Geology, mineralization and genesis of the Madabad celestite deposit, south Zanjan
  مهسا  نوری Hossein Kouhestani قاسم  نباتیان میرعلی اصغر  مختاری افشین  زهدی
  20.1001.1.17357128.1400.15.60.4.2
  Rock units in the Madabad celestite deposit are composed of medium to thick-bedded and massive limestone interlayered with marly limestone and marl units of the Qom Formation (lower Miocene). Mineralization occurs as lens-shaped orebody, hosted by limestone units of mem More

  Rock units in the Madabad celestite deposit are composed of medium to thick-bedded and massive limestone interlayered with marly limestone and marl units of the Qom Formation (lower Miocene). Mineralization occurs as lens-shaped orebody, hosted by limestone units of member of the Qom Formation usually crosscutting bedding of the host rocks. Three stages of mineralization occurred in the Madabad deposit. The first stage is characterized by calcite formation during syn-depositional to syn-diagenesis processes. The second stage is related to hydrothermal processes that are distinguished by formation of fine-grained and sugary crystals of massive stage-1 celestite, vein-veinlets of coarse-grained stage-2 celestite along with minor strontianite and barite, coarse-grained euhedral crystals of stage-3 celestite with vug infilling texture, and finally late-stage quartz and calcite vein-veinlets. Stage three includes supergene processes. Hydrothermal alteration includes dolomitization, calcitization and silicification. Celestite along with minor strontianite and barite are ore minerals, and calcite, dolomite, quartz and iron oxides-hydroxides are gangue minerals at Madabad. The ore minerals show vein-veinlets, vug infilling, brecciated and cataclastic textures. Microthermometric measurements of two-phase liquid-rich fluid inclusions hosted in celestite II indicate that salinities values range from 6 to 18 wt.% NaCl equiv. (avg. 10.6 wt.% NaCl equiv.). These inclusions have homogenization temperatures range from 248 to 365 °C, with an average of 278 °C. These data indicate a minimum trapping depth of 510 m for the Madabad deposit. Sr was originated from evaporate units within the marly parts of the Qom Formation and volcanic units of the Karaj Formation. Characteristics of the Madabad deposit are similar to epigenetic replacement celestite deposits. Manuscript profile
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  10 - Geology, mineralization, mineralogy, structure and texture in the Ghezeljeh Cu, Pb-Zn deposit, NW Zanjan
  Seyedeh Aliyeh  Seyedeh Aliyeh Ghasem Nabatian Afshin  Zohdi Armin  Salsani
  20.1001.1.17357128.1402.17.65.4.6
  Ghezeljeh deposit is located in the Central Iranian zone, in the Zanjan province and northeast of the Mahneshan city. The rock units in this area belongs to the Oligo-Miocene, which contain Lower Red, Qom and Upper Red formations. The Upper Red Formation in Ghezeljeh re More

  Ghezeljeh deposit is located in the Central Iranian zone, in the Zanjan province and northeast of the Mahneshan city. The rock units in this area belongs to the Oligo-Miocene, which contain Lower Red, Qom and Upper Red formations. The Upper Red Formation in Ghezeljeh region has about 750 m thickness and mainly consists of brown to green marl intercalations with sandstones. In this area, the alternation of marl and sandstone sequences contain sandstone layers with thickness about 2 to 8 meters, which in two horizons, the copper-lead and zinc mineralization has occurred. Copper mineralization, in addition to being observed inside the sandstone unit. In the Ghezeljeh deposit, the host rocks of the copper ores, are gray sandstones and conglomerates which are intercalated with red and gray marl units. According to field and microscopic studies, the main ore mineral consist of pyrite, chalcocite, chalcopyrite, bornite, galena and sphalerite which associated with the secondary minerals such as serosite, malachite, azurite, covellite, smithzonite and goethite. The ore mineral textures consist of disseminate, framboidal pyrite, solution seams, interparticle cement, replacement and relict. Preliminary fieldwork studies in the Ghezeljeh region also show that organic matter including plant remains and diagenetic pyrite are the effective factors to concentrate and mineralization. It is considerable that the grade of lead, zinc and copper, in Ghezeljeh deposit are 6%, 3% and 1%, respectively. Generally, host rock, tectonic setting, sedimentary environment, mineralogy, texture, mineralization control factors all confirm that the studied mineralization has more similarities with Redbed type copper deposits. Manuscript profile