List of Articles Qom Formation

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  1 - Microfacies, sedimentary environment and sequence stratigraphy of the Qom Formation in East Siyah Kuh surface section (South of Garmsar)
  Mahmoud Jalali Mahmoud Jalali محمد حسين  آدابي
  This paper represents the sequence stratigraphic analysis of the Oligo-Miocene shallow water carbonate succession of the Qom Formation, east of Kuh Siah outcrop (South of Garmmsar). The study is based on the lithosratigraphy, biostratigraphic framework (in the contex More

  This paper represents the sequence stratigraphic analysis of the Oligo-Miocene shallow water carbonate succession of the Qom Formation, east of Kuh Siah outcrop (South of Garmmsar). The study is based on the lithosratigraphy, biostratigraphic framework (in the context of European standard biozonation), microfacies, paleoenvironmental interpretation and sequence srtatgraphic concepts. In this section, only f to c1 members of the Qom Formation can be differentiated. The biostrtigraphic results revealed that the benthic foraminiferal composition of the studied section has close affinities with coeval assemblages in Western Tethys and the Middle East. The larger foraminifera associations in the Qom Formation mark the SBZ 23 to 25 zones, referring to a time span from the late Chattian to Burdigalian. Based on the micropaleontological studies, the age of late Chattian (SBZ 23) is ascribed to c1 member which previously considered as Aquitanian, in East of Siah Kuh surface section. Sedimentary environment of the Qom Formation is related to a carbonate ramp platform. Based on sedimentary texture and percentage of skeletal and non skeletal allochems, 1 lithofacies and 13 microfacies from inner to outer ramp were determined. The sequence stratigraphic studies led to the determination of four 3rd order sequences. The first sequence with the Chattian age includes c1 and c2 members. The second sequence with the Aquitanian age includes c3, c4 and d members. The e and f members belong to third and fourth sequences with the age of Burdigalian. Manuscript profile
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  2 - Biostratigraphy and paleoecology of the e Member of the Qom Formation based on Ostracoda at Cheshmeh Boroun section, West of Qom
   Daneshian مسعود گودرزی
  The aim of this study is determining systematics and identification of ostracods genera and species of the e Member of the Qom Formation at the studied section (Cheshmeh Boroun) for biostratigraphy and age determination, and palaeoecological investigations considering t More

  The aim of this study is determining systematics and identification of ostracods genera and species of the e Member of the Qom Formation at the studied section (Cheshmeh Boroun) for biostratigraphy and age determination, and palaeoecological investigations considering the abundance and diversity changes of ostracods based on the collected data. The abundance and diversity of the ostracods taxa such as Paracypris، Aurila ،Ruggieria ،Loxochoncha ، Krithe، Xestoleberis, Cytherella mostly suggest a marine environment with normal salinity and warm climate from ecological point of view. However, the increase and decrease of these taxa in the studied section indicate the diversity and abundance changes is related to environmental changes. In fact, this shows the instability of the environmental conditions which seems to be affected by the changes of food and oxygen values, and water turbulence. Based on ostracods assemblages, an Early Miocene age ( Aquitanian- Burdigalian) is exclusively suggested for the e Member of the Qom Formation at Cheshmeh Boroun stratigraphic section. 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
           
  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
    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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  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
   
  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 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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  8 - 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