List of Articles رخساره

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  1 - Stratigraphy and depositional environments of the Shurijeh Formation in Baghak, Mozduran sections and Khangiran well, east of Kopet Dagh Basin
  امیرمحمد  جمالي Ahmad Ahmadi Khalaji Samaneh Falah
  Late Cimmerian tectonic phase was the main cause for depositing terrigenous-evaporite sediments of the Shurijeh Formation in large area of eastern and central part of Kopet Dagh Basin during Late Jurassic-Early Cretaceous. In order to recognize facies changes and depos More

  Late Cimmerian tectonic phase was the main cause for depositing terrigenous-evaporite sediments of the Shurijeh Formation in large area of eastern and central part of Kopet Dagh Basin during Late Jurassic-Early Cretaceous. In order to recognize facies changes and depositional environments of the Shurijeh Formation in east of the Kopet Dagh, 3 stratigraphic sections including Baghak and Mozduran surface sections and a well from Khangiran gas field were selected and studied. Field surveys together with microscopic studies of 311 thin sections reveal that depositional environment of the lower part of the Shurijeh Formation is mainly interpreted as fluvial environment, especially braided and meandering rivers. In the upper part of this formation, coastal plain and tidal flat facies, which locally contain lagoon and shoal sediments, are observed. Manuscript profile
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  2 - Cruziana ichnofacies from Nayband Formation (Late Triassic) in the Parvadeh section, Southwest Tabas, East central Iran
  Nasrollah Abbassi Mohammad ghavidel Morteza Yosefi Navid Navidi Izad
  Nayband Formation is composed of sandstone, coal bearing shales, siltstone, and fossiliferous limestone in the southwest Tabas section, east central Iran. In this section, it is 1410 m in thickness and Late Triassic in age. A divers trace fossils have been found in the More

  Nayband Formation is composed of sandstone, coal bearing shales, siltstone, and fossiliferous limestone in the southwest Tabas section, east central Iran. In this section, it is 1410 m in thickness and Late Triassic in age. A divers trace fossils have been found in the middle parts of sequence as 400-600 m. These trace fossils include Lockeia isp., Palaeophycus tubularis, Palaeophycus striatus, Planolites beverleyensis, Rhizocorallium isp., Rosselia isp., and cf. Treptichnus isp. This ichnoassemblage is attributable to Cruziana ichnofacies with presence of Lockeia isp., Rhizocorallium isp., and, Rosselia isp. This part of Nayband Formation was deposited in low energy conditions below fair-weather wave base. Manuscript profile
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  3 - Robustness of fuzzy c-mean method for delineation of hydrochemical facies distribution of groundwater in Varamin Plain
  Mohammad Nakhaei Mehdi Talkhabi Meysam Vadiati
  In this paper, classification of a large hydrochemical data set from Varamin plain is done by using fuzzy c-means (FCM) and hierarchical cluster analysis (HCA) clustering techniques. Then its application to hydrochemical facies delineation is discussed. Groundwater samp More

  In this paper, classification of a large hydrochemical data set from Varamin plain is done by using fuzzy c-means (FCM) and hierarchical cluster analysis (HCA) clustering techniques. Then its application to hydrochemical facies delineation is discussed. Groundwater samples were grouped into three classes according to the optimum number of the classes and fuzziness exponent by using the fuzzy c-mean. The data set includes 90 deep and moderate deep well samples from groundwater data set and 9 hydrochemical variables were used. Results from both FCM and HCA clustering produced cluster centers that can be used to identify the physical and chemical processes creating the variations in the water chemistries. The optimum cluster in FCM method determined by optimization function, but in HCA method by trial and error. The FCM method is potentially useful in establishing hydrochemical facies distribution and may provide a better tool than HCA for clustering large data sets when overlapping or continuous clusters exist. Plotting the cluster membership value contours on a map demonstrated the existence of three spatially continuous, well-defined clusters of groundwater samples. The results showed that the FCM method is more sound for investigating threshold data rather than HCA method (that represents sharp and abrupt variations). Manuscript profile
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  4 - Microfacies, Sedimentary Environment and Sequence Stratigraphy of the Qom Formation, Deh Namak, Northwest of Garmsar
  Jahanbakhsh Daneshian  Asadi Mehmandosti yousef ramezani
  Deh Namak section is exposed along the most northern point of the Qom Formation, where the Central Iran zone and Alborz zone come together. The study of microfacies, sedimentary environments and sequence stratigraphic features of the Qom Formation in this area can h More

  Deh Namak section is exposed along the most northern point of the Qom Formation, where the Central Iran zone and Alborz zone come together. The study of microfacies, sedimentary environments and sequence stratigraphic features of the Qom Formation in this area can help to understand the situation of the Qom sedimentary basin in the northern part, bordering the Alborz zone. 166 samples of the Qom Formation in Deh Namak section in the northwest of Garmsar are investigated. Microfacies analysis of these sedimentary rocks indicates that according to sedimentary environment they consist of nine microfacies belonging to four facies belts including tidal flat, agoon, shoal/reef sediments and slope of platform. Due to the absence of the gravitational and turbidity sediments and abundance of reef/shoal sediments, a rimmed carbonate shelf depositional environment is suggested in which more sediments were precipitated in shallow water. In this model, deep facies of the basin did not spread and the deepest facies belong to the slope. Also, sequence stratigraphic studies show that the Deh Namak section is composed of four sedimentary sequences of third- order, two types II and one type I sequence boundaries were recognized in this formation. Manuscript profile
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  5 - Microfacies and sedimentary environment of the Maastrichtian deposits in Jorbat Stratigraphic section, west of Kopet Dagh
  Yadolah Ezampanah Mahmoud Jalali محمد حسين  آدابي امیرمحمد  جمالي
  To determine microfacies and depositional subenvironments of the Maastrichtian deposits in the western part of the Kopet-Dagh Basin, one stratigraphic section, has been selected and analysed. In this section which is located 9.5 kms N-NW of Jorbat, Maastrichtian deposit More

  To determine microfacies and depositional subenvironments of the Maastrichtian deposits in the western part of the Kopet-Dagh Basin, one stratigraphic section, has been selected and analysed. In this section which is located 9.5 kms N-NW of Jorbat, Maastrichtian deposits are composed of two formations including Kalat (282 m thickness) and Chakhmaghlo (77 m thickness). The Kalat Formation consists of bioclastic and sandy limestone and the Chakhmaghlo Formation is composed of shale, marl, limestone and argillaceous limestone. Based on field observations and also petrographic studies, the lower boundary of the Kalat Formation with the Abderaz Formation is disconformable. The lower boundary of the Chakhmaghlo Formation with the Kalat Formation is gradual and conformable, while its upper contact with the Paleocene Pesteligh Formation is disconformable. Petrographic studies in Maastrichtian deposits led to recognition of 16 microfacies. These microfacies deposited in 5 facies belts including tidal flat, lagoon, shoal, reef and fore reef subenvironments in a carbonate platform. Manuscript profile
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  6 - Facies and depositional model in siliciclastic Chelken Formation, South Ghaemshahr City
  هوشنگ  مهرابی عبدالحسین  امینی وحید توکلی مرتضی  فرخی Seyed Mohad Zamanzadeh
  20.1001.1.17357128.1399.14.55.7.8
  Siliciclastic Chelken Formation (Lower and Middle Pliocene) with a siliciclastics nature in Javarom Section (south of the Ghaemshahr city) was studied. This formation comprises three sets of conglomerate, sandstone and mudstone, which are usually arranged in fining upwa More

  Siliciclastic Chelken Formation (Lower and Middle Pliocene) with a siliciclastics nature in Javarom Section (south of the Ghaemshahr city) was studied. This formation comprises three sets of conglomerate, sandstone and mudstone, which are usually arranged in fining upwards sequences. According to the nature of fining upward sedimentary sequences, sedimentological characteristics and structural features, it is proposed that Chelken Formation deposited in a fluvial environment. Conglomeratic facies are mainly grain-supported in nature, sandstone facies are represented by quartz arenite and lithic arenite in nature and Mudstone facies are carbonate in nature. The paleo-currents analyses represent a north and northeastward direction Manuscript profile
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  7 - Facies studies and depositional environment of Sahand volcanic complex (NW of Iran)
  Farhad Pirmohammadi alishah Ahmad Jahangiri
  20.1001.1.17357128.1400.15.58.3.7
  Sahand volcanic complex is located in the south of Tabriz and east of Urmia Lake and includes an alternation of lava, igneous materials and clastic sediments that were affected by many folds and fractures. Sahand volcano is relatively young in age (Miocene to Pliocene) More

  Sahand volcanic complex is located in the south of Tabriz and east of Urmia Lake and includes an alternation of lava, igneous materials and clastic sediments that were affected by many folds and fractures. Sahand volcano is relatively young in age (Miocene to Pliocene) and its structure is somewhat intact. Consequently, where there is a good lateral continuity, facies and volcanological studies can be carried out in the upper part of the complex. Based on these studies, it was determined that the Sahand volcanic structure can be divided into four central, near, medium and distant facies. Facies studies show that the structure of Sahand Volcano was created by several explosive phases, some of which were associated with water intrusion and there was not much time between eruptions. Characteristics, such as severe welding and discoloration of pyroclastic deposits show that these units had a high temperature at the time of formation and were formed on land. Overall, Sahand volcanic eruptions were more explosive, and thus, the number of pyroclastic deposits is much higher than lava flows. In the central, near and middle facies of Sahand, no traces of younger hydrothermal activities can be found, and only in the distant facies, there is a hot spring (Bostan Abad), the relationship of which needs further study to prove the connection of these springs with the Sahand Volcano. Manuscript profile
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  8 - Basic steps in determining the provenance of terrestrial sedimentary sequences, with examples from central and north west of Iran
  عبدالحسین  امینی
  20.1001.1.17357128.1400.15.60.5.3
  By stating the fundamental differences between terrestrial and detrital facies, this paper emphasizes on the limitations of provenance studies in terrestrial facies. Considering the presence of coarse-, medium- and fine-grained facies in most of terrestrial sedimentary More

  By stating the fundamental differences between terrestrial and detrital facies, this paper emphasizes on the limitations of provenance studies in terrestrial facies. Considering the presence of coarse-, medium- and fine-grained facies in most of terrestrial sedimentary sequences, the differences in textural and mineralogical characteristics, their study methods and possible differences in the provenance of these facies, the basic and necessary steps in studying these facies for determining the sedimentary provenance was investigated. In explaining these steps, some examples from terrestrial formations of Central Iran (Upper Red Formation) and north west of Iran (Zivar Formation) are presented. The role of diagenesis, structural deformation and paleogeography in the provenance study and their importance in this type of studies are explained. Finally, it is discussed how to proof the accuracy of the interpretations for the studied sedimentary sequences. Manuscript profile
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  9 - An investigation on sedimentary facies and hydrochemistry characteristics of carbonate deposits in the Ab-e Ask region, Southeast of Damavand volcano
  S.  Rahmani Javanmard Mohsen Ranjbaran V. Amiri
  20.1001.1.17357128.1401.16.62.5.4
  Calcareous springs of Ab-e Ask are located 85 km northeast of Tehran, in the southern range of the Damavand volcano. Microscopic studies represent the existence of four abiotic and two microbialite facies in the Ab-e Ask travertines. The travertines are the main deposit More

  Calcareous springs of Ab-e Ask are located 85 km northeast of Tehran, in the southern range of the Damavand volcano. Microscopic studies represent the existence of four abiotic and two microbialite facies in the Ab-e Ask travertines. The travertines are the main deposit types of these springs. Based on sedimentation sequence and lithofacies these travertines are categorized as first type (vent and channel), second type (pound, dam, and cascade), and third type (laminated) travertines. On a δ18O versus δ13C plot (VPDB), these travertines are plotted in the oncoid and crystalline crust lithofacies fields. These facies show the character of hydrothermal spring and set the spring in the thermogenic group. Positive values of the Langelier Saturation Index (LSI) for Pashnak, Nadaali, and Zagh springs indicate that these water samples are supersaturated with respect to calcium carbonate, which leads to considerable sedimentation around the springs. In contrast, a negative LSI value at the Sare Pole spring indicates the water is undersaturated with respect to calcium carbonate. Therefore, this spring has a lesser role in travertine deposition compared to the other springs. Also, the position of the samples on the modified Gibbs and Van Wirdum diagrams, suggests that the interaction of water with carbonate and to some extent silicate rocks is considered as the most important source of Ca and Na. Manuscript profile
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  10 - Facies analysis and sedimentary environment of the Jeirud Formation in Garmabdar section, central Alborz: with emphasis on paleoredox conditions during deposition of black shales
  Nahid Karimi Najmeh  Etemad-Saeed Aram Bayet-Goll Afshin  Zohdi Tomas Kumpan
  20.1001.1.17357128.1401.16.63.4.5
  The late Devonian has been associated with major global climate changes, widespread anoxia events, and the Hangenberg Crisis. The main aim of this study is to explore the relationship between paleoenvironment and paleoredox condition during deposition of the lower Devon More

  The late Devonian has been associated with major global climate changes, widespread anoxia events, and the Hangenberg Crisis. The main aim of this study is to explore the relationship between paleoenvironment and paleoredox condition during deposition of the lower Devonian Jeirud Formation in the Garmabdar section, northeast of Tehran. The Jeirud Formation in the Garmabdar section, with a thickness of about 280 m, is composed of siliciclastics, carbonates, carbonate-siliciclastic hybrids and phosphorite deposits. Sedimentary facies analysis led to recognition of three siliciclastic facies associations related to estuarine environments under the influence of waves, shoreface and offshore and two carbonate facies associations related to intertidal and subtidal environments. Moreover, the geochemical paleoredox proxies (such as U/Th and V/Cr) also suggest prevailing anoxic conditions during deposition of black shales and phosphorites in the studied section. In overall, these results suggest that there is a good agreement between the depth of the depositional environment and anoxic conditions during deposition of black shales of the Jeirud Formation. Manuscript profile
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  11 - The history of deposition and post-deposition and their effects on the reservoir quality of Asmari Formation in Ahvaz oilfield
  Akbar Heidari Milad Faraji Narges Shokri
  The carbonate interval of the Asmari formation along with sandstone deposits were deposited in most areas of the Zagros sedimentary Basin, including the Ahvaz area, in Oligo-Miocene. In this study, the effects of depositional and post-depositional environments on the re More

  The carbonate interval of the Asmari formation along with sandstone deposits were deposited in most areas of the Zagros sedimentary Basin, including the Ahvaz area, in Oligo-Miocene. In this study, the effects of depositional and post-depositional environments on the reservoir quality of zone A7 of the Asmari Formation in well No. 4 in Ahvaz oil field were studied. The study of the sequences of the Asmari Formation in this section led to the identification of 11 carbonate facies, one evaporite facies, one mixed carbonate-siliciclastic facies, and one siliciclastic facies. Sedimentary environments of tidal zone, lagoon, coral reef and open sea were introduced for the depositional environment of identified facies. Due to the absence of sudden changes, it seems that the studied deposits were deposited in a ramp-type carbonate platform that was influenced by siliciclastic sediments from the Zagros river systems. The immature sedimentary texture of the sandstone facies indicates the proximity of the origin of the quartz sources to the carbonate basin. Among the diagenetic processes that have affected the examined sequences, the following processes can be mentioned: micritization, cementation, neomorphism, physical and chemical compaction, dissolution, fracture development and filling, dolomitization, and anhydritization. These diagenetic processes occurred in post-depositional marine, meteoric and burial diagenetic environments. Many fractures were filled with petroleum, which indicates that fractures, along with dolomitization, chemical compaction, and fenestral pores, are among the most important post-sedimentation complications to increase reservoir quality. While cementation and anhydritization resulted in reducing the reservoir quality by closing the pore spaces . Manuscript profile
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  12 - Reconstruction of Jeirud Formation depositional environment in Aro Section (Central Alborz)
  Seyed Mohammad Zamanzadeh M. Ranjbaran K. Ghaffari
  In this paper it is attempted to reconstruct the depositional environment of the Jeirud Formation in Aro section. The Jeirud Formation (Late Devonian) is composed of about 45 meters of clastic sedimentary units in the southwest of Firoozkuh city, southern Alborz area. T More

  In this paper it is attempted to reconstruct the depositional environment of the Jeirud Formation in Aro section. The Jeirud Formation (Late Devonian) is composed of about 45 meters of clastic sedimentary units in the southwest of Firoozkuh city, southern Alborz area. To carry out this research a field work was done during which a precise and detailed sedimentary log of the section was prepared and 52 samples from different lithologies of the formation were collected. Thin sections were prepared from all conglomeratic and sandstone samples, besides some thin sections were prepared from mudrocks and just 1 sample of paleosoil and then all were petrographically studied. In the study area, both basal and top boundary of the Jeirud Formation is disconformable with Mila and Mobarak formations respectively. All facies in the section include clastics (conglomerates, sandstones, mudstones and a paleosoil horizon). The facies were classified based on Miall classification so that conglomeratic facies comprise Gcm and Gmm; sandstone facies comprise Sh, Sp and Sm and mudrocks include Fl and Fm facies. Combined field and lab studies resulted in identification of two sedimentary facies associations including channel fill and flood plain facies associations. The reconstructed sedimentary environment of the Jeirud Formation in the Aro area represents a braided river depositional environment. The lower parts of this formation represent a finning-upward sequence which indicates deposition within a braided river channel subenvironment (conglomerates and sandstones) and the upper part is dominated with mudrocks with a paleosoil horizon representing deposition in a flood plain subenvironment. Manuscript profile
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  13 - Reservoir quality evaluation of the Asmari Formation in the framework of sequence stratigraphy in one of the Iranian SW oilfield
  Ebrahim Sfidari A. Hakymi-Zanuz
  The Oligo-Miocene Asmari Formation forms the main reservoir rock of many Dezful Embayment fields. Microfacies analysis, diagenetic features, and sequence stratigraphic evaluation of the Asmari Formation were carried out based on the petrographic investigation, petrophys More

  The Oligo-Miocene Asmari Formation forms the main reservoir rock of many Dezful Embayment fields. Microfacies analysis, diagenetic features, and sequence stratigraphic evaluation of the Asmari Formation were carried out based on the petrographic investigation, petrophysical logs, and core measurement porosity and permeability data. Petrographic analyses led to the identification of twelve microfacies indicating five subenvironments including tidal flat, lagoon, barrier (belonging to inner ramp), middle ramp, and outer ramp, all of which are representing a homoclinal ramp. Tidal flat, lagoonal, and barrier microfacies are mostly present in the upper parts of the Asmari Formation, while middle and outer ramp microfacies were largely developed in the middle part. Cementation, compaction, dolomitization, dissolution, and fracturing are the main diagenetic processes in this formation. Compaction and cementation have negatively affected reservoir quality while fracturing, dolomitization, and dissolution contributed to reservoir quality enhancement. The sequence stratigraphic studies represent three 3rd order sequences of early Aquitanian, late Aquitanian, and early Burdigalian age based on the main features of microfaces, their depositional environments, and shallowing and deepening-upward trends. Microfacies of the Transgressive System Tract (TST) have been affected by compaction, dissolution (moldic), cementation, and slightly dolomitization in the middle to outer ramp parts. The Highstand System Tract in the inner ramp part has been affected by dolomitization, dissolution, and fracturing close to the sequence boundaries, and has a better reservoir quality than the Transgressive System Tract. Manuscript profile