List of Articles Reservoir quality

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  1 - Iagenetic controls on reservoir quality of the Asmari carbonate succession in the Cheshmeh Khush Field, SW Iran
  جواد هنرمند عبدالحسین امینی
  20.1001.1.22518738.1391.2.3.2.1
  The Oligo-miocence Asmari Formation in the Cheshmeh Kush Oil Field consists of a mixed carbonate-siliciclastic succession. The carbonate intervals of the Formation display a high degree of vertical heterogeneity created by a complex diagenetic history. This study is aim More

  The Oligo-miocence Asmari Formation in the Cheshmeh Kush Oil Field consists of a mixed carbonate-siliciclastic succession. The carbonate intervals of the Formation display a high degree of vertical heterogeneity created by a complex diagenetic history. This study is aimed to investigate the effect of diagenetic events on reservoir quality of carbonate intervals of the Asmari Formation. Core samples and thin sections were studied from sedimentological and diagenetic point of view. Results from cathodoluminesence and scanning electron microscopy were used to investigate diagenetic features in details. Core analysis data (porosity and permeability) and wire-line logs (porosity and oil saturation values) from studied interval were used in order to examine reservoir properties. Diagenetic studies and their comparison with petrophysical data demonstrated that dolomitization, cementation (calcite, anhydrite and celestite cements), compaction and dissolution are the most important diagenetic events affecting porosity and permeability of the reservoir. Based on vertical distribution of diagenetic features and reservoir characteristics, diagenetic zones (DZ) of the carbonate succession were introduced. Medium crystalline dolostones with sparse compaction features and limited anhydrite cement (DZ-23, 27 and 30) comprise the highest value of porosity and permeability. Whereas intense mechanical and chemical compaction and evaporate (anhydrite and celestite) cementation in some dolomitic intervals have thoroughly reduced reservoir quality (DZ-12, 11 and 24). Compaction and calcite cementation (coarse spary, equant and poikilotopic types) in some limestone intervals damaged reservoir properties and created non-reservoir intervals (DZ-3, 20 and 17). In contrast, high value of interparticle and dissolution porosities along with minor compaction and cementation effects has improved reservoir properties of the Asmari limestones (DZ-31 and 32). This study shows that the reservoir characteristics of the Asmari Formation in the studied field are dominantly affected by diagenetic events and therefore diagenetic studies and determination of diagenetic zones in field-scale are the most important part in static reservoir modeling and Manuscript profile
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  2 - Analysis of Electrical Rock Type Bangestan Reservoir in Marun Oil Field
  Abouzar Mohsenipour Bahman Soleimani Ehsan Abharakpour Ghodratollah   Nikkhah
  20.1001.1.22518738.1395.6.12.1.6
  Studies of the electrical Rock Type a very important role in the development process plays a field.In these studies, theporo-perm Cores data and well log data used for reservoir simulations. In the present research, the flow of four flow units was determined in the res More

  Studies of the electrical Rock Type a very important role in the development process plays a field.In these studies, theporo-perm Cores data and well log data used for reservoir simulations. In the present research, the flow of four flow units was determined in the reservoir using porosity and permeability data from well logging core by regional index method. In some wells, using well logging the basic model of electrical rocktype was determined with three methods of MRGC, SOM, and DYNAMIC. The determined facies by different methods were correlated with the flow unit. Finally, SOM method was selected, which has the best concordance. The initially created electrofacieswere reduced to 4 electrofacies due to the similarity of some parameters such as effective porosity and gamma logging. To ensure the accuracy of the electrical rock type by neural networks, these electrofacies were correlated with capillary pressure data. After confirming the determined electrofacies by capillary pressure, these facies were propagated in other wells in this field. This created a model, which was able to separate different parts of the reservoir. In this model, different parts of the reservoir were determined in terms of reservoir quality. Manuscript profile
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  3 - Relation between microfacies, depositional environment and diagenesis with reservoir quality the Jahrum Formation in well no. 11, Golkhary oil field, Zagros basin
  Maryam Sinapour Naser Arzani
  20.1001.1.22518738.1395.6.11.3.6
  In this study the relationship between petrographic studies (microfacies, environment of deposition and diagenesis) and petrophysical data of core analysis in order to identify reservoir quality of the Jahrum Formation in well no. 11 at the Golkhary oil field. The Go More

  In this study the relationship between petrographic studies (microfacies, environment of deposition and diagenesis) and petrophysical data of core analysis in order to identify reservoir quality of the Jahrum Formation in well no. 11 at the Golkhary oil field. The Golkhary oil field is located at the west of Qatar-Kazerun fault, in between Binak and Nargesi oil fields. The Jahrum Formation consists of limestone, dolomite limestone and dolomite. Petrographical studies accomplish in two parts microfacies studies led to the recognition of 9 microfacies that were deposited in 3 facies belt tidal flat, lagoon and open marine environment. In diagenesis studies the most important factors included bioturbation, micritization, mechanical compaction, secondary porosity, secondary anhydrite cement, calcite burial cement, stylolites and solution seams, replacement dolomite, dolomite cement and hydrocarbon shows. Porosities identified are intercrystalline, intergrain, intrafossil and intragrain, moldic, fracture, solution along stylolite, solution enlarge and shelter. The results of this study shows that Grain supported MF3 (Bioclast Nummulitidae Rotalia wackestone/ packstone/ grainstone) and MF4 (Bioclast Nummulitidae Orbitolites packstone/ grainstone/ floatstone) due to the presence in the environment energetic, micrite absence, lack of widespread cement, presence of effective porosities includes intergrain porosity and intercrystalline porosity identified are reservoir microfacies. Petrophysical data with high levels of permeability and effective porosity between these two microfacies is the confirmation of the results of petrographic studies. Manuscript profile
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  4 - Electro-facies analysis of the Sarvak Formation (Middle Cretaceous) and compliance with sedimentary microfacies in an oil field, SW Iran.
  zahra Eghbalkiani Taher Goli ALI HOSSEIN JALILIAN Rahym Kadghodaii
  20.1001.1.22518738.1395.6.11.5.8
  Electro-facies analysis is a sure method in clustering petrophysical logs analysis that can well indicates the changes of geologic charactereristics of the different lithostratigraphic units as well. Petrographic studies of 120 prepared thin sections of the upper parts More

  Electro-facies analysis is a sure method in clustering petrophysical logs analysis that can well indicates the changes of geologic charactereristics of the different lithostratigraphic units as well. Petrographic studies of 120 prepared thin sections of the upper parts of the Sarvak Formation in studied oilfield, Southwestern Iran, has resulted in definition of 6 microfacies sedimentary types. These data suggested that the middle Creataceous sediments in the studied area were predominantly deposited in two subenviornments of patch organic barrier and lagoon corresponding to inner and shallow a homoclinal ramp. In addition, using petrophysical logs in the studied well, 10 electrical facies were determined. By analyzing the data petrophysical in Geolog software, 10 electerical facies were optimized and then their number was reduced to six. According to good adaptation of optimized electerical facies with sedimentary microfacies, we would generalized obtained dresults to all parts of the Sarvak Formation. Study of porosity changes in the electrical diagrams such as CGR corrected Gamma, and sonic curves in mentioned well, indicated a significant reduction in facies porosity of 1 to 6. In addition, the results showed that the reservoir quality reductionin studied microfacies is corresponded to Bioclastic Rudist debris floatstone/ Rudstone, Benthic foraminifera Rudist debris wackestone / packstone, Benthic Foraminifera peloid Grainstone/Packstone, with High diversity benthic foraminifera wackestone / packstone, Peloid bioclastic wackestone /packstone with Low diversity benthic Foraminifera and Mudestone/Wackestone, respectively. In this study, we concluded that comparison and correlation sedimentary facies with electric microfacies provide an efficient method to study the quality of the hydrocarbon reservoir system that especially can be used in other wells with no core. Manuscript profile
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  5 - The impact of microfacies and diagenesis characteristics on the reservoir quality of Asmari Formation in the Gevarzin gas field, Zagros basin, south Iran
  Karim  Mombani   Ahmad Yahyaei
  20.1001.1.22518738.1398.9.17.4.0
  Asmari Formation from the Gavarzin gas field have erosional unconformity boundary on marl and pelagic limestones of Pabdeh Formation and gradually change to evaporate cap rock of Gachsaran Formation. Cores studies from the one of wells of Gavarzin field is 183 m in thic More

  Asmari Formation from the Gavarzin gas field have erosional unconformity boundary on marl and pelagic limestones of Pabdeh Formation and gradually change to evaporate cap rock of Gachsaran Formation. Cores studies from the one of wells of Gavarzin field is 183 m in thickness, which includes 1.30 m from the top of Pabdeh, 162.4 m from the Asmari Formation and 19.30 m from the base layers of Gachsaran. Asmari Formation includes alternation of limestone, calcite dolomitic, claystone and shale with green marl. Petrology and facies analysis of the sequence of these formations identified 12 microfacies, a carbonate ramp from deep-sea to sabkha environments and formed in a retrograded sequence. This ramp includes deep environments, open sea, patch reef, bio-, clastic-bars, lagoon and tidal environments, which confirms a changing environment due to rapid facies changes and deposition of evaporative sediments in Gachsaran as a restricted environment. Diagenesis processes are considered as the main factors in carbonate reservoir quality of Gavarzin field. The diagenesis history of the Asmari carbonates of the studied cores is summarized as A) marine phreatic diagenesis, bioturbation, micritization and cementation processes occurred. B) vadose zone diagenesis, where the crystallization, cementation, and dissolution occurred. C) burial diagenesis, comprises compression-induced, pressure dissolution and fracturing are common. The microfacies show a wide varieties of reservoir characteristics and therefore a heterogeneous reservoir has been formed. Micro-fractures, however have strongly influence on the reservoir quality in the section. The simultaneous presence of dissolved spaces and fractures in the reservoir the permeability greatly increased. The best reservoir quality in the Grainstone/Packston facies are coated grains with moldic porosity that were created by the leaching of Ooid-bearing Packston lithology during the diagenesis of atmospheric waters. Manuscript profile
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  6 - Interpretation of sedimentary environment and factors affecting reservoir quality in upper Sarvak Formation in one the oil fields of Abadan plain
  Mohammad Hossein Saberi Bahman Zarenezhad الهام  اسدی Nasim Rahmani
  The Sarvak Formation of the Albian-Turonian Formation is one of the most important hydrocarbon reservoirs in south and southwest of Iran. In this study, in order to assess the reservoir quality, from a petrographic study and porosity and permeability data, an important More

  The Sarvak Formation of the Albian-Turonian Formation is one of the most important hydrocarbon reservoirs in south and southwest of Iran. In this study, in order to assess the reservoir quality, from a petrographic study and porosity and permeability data, an important well in one of the oil fields of Abadan plain has been used. Based on microscopic studies, 13 microfacies have been identified in the form of Four facies tidal flat, lagoon, shoal and open marine for Sarvak Formation deposits in the studied oil field, indicating that the upper part of the Sarvak Formation is deposited in a homoclinal carbonate ramp. Among the identified diagenetic processes, dissolution, cementation, dolomitization, fracturing, compaction, neomorphism, micritization, bioturbation, pyritization, hematitization, phosphatization and silicification are mentioned. Diagenetic processes of Sarvak Formation occurred in three marine, meteoric and burial environments. Among the dissolution and fracturing diagenetic processes, the most important role has been in increasing the reservoir quality, and cementation and compaction have been the most important factors in reducing reservoir quality. Sequence stratigraphy studies identified third order sedimentary sequences of the age of Turonian, Late Cenomanian, and Middle Cenomanian, and studied the facies and diagenetic processes within its framework. Correlation of porosity and permeability data of the core showed that the reservoir quality in this formation was influenced by facies and diagenetic processes. So that the microfacies containing the rudist have the highest reservoir quality. Due to the diagenetic processes, sedimentary and porosity and permeability data, the facies shoal and open marine to the land have the best reservoir quality. Manuscript profile
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  7 - Interpretation of sedimentary environment and factors affecting reservoir quality in upper Sarvak Formation in one the oil fields of Abadan plain
  Arad Kiani Mohammad Hossein Saberi Bahman Zare nejad Elham Asadi Nasim Rahmani
  20.1001.1.22518738.1397.8.16.6.3
  The Sarvak Formation of the Albian-Turonian Formation is one of the most important hydrocarbon reservoirs in south and southwest of Iran. In this study, in order to assess the reservoir quality, from a petrographic study and porosity and permeability data, an importan More

  The Sarvak Formation of the Albian-Turonian Formation is one of the most important hydrocarbon reservoirs in south and southwest of Iran. In this study, in order to assess the reservoir quality, from a petrographic study and porosity and permeability data, an important well in one of the oil fields of Abadan plain has been used. Based on microscopic studies, 13 microfacies have been identified in the form of Four facies tidal flat, lagoon, shoal and open marine for Sarvak Formation deposits in the studied oil field, indicating that the upper part of the Sarvak Formation is deposited in a homoclinal carbonate ramp. Among the identified diagenetic processes, dissolution, cementation, dolomitization, fracturing, compaction, neomorphism, micritization, bioturbation, pyritization, hematitization, phosphatization and silicification are mentioned. Diagenetic processes of Sarvak Formation occurred in three marine, meteoric and burial environments. Among the dissolution and fracturing diagenetic processes, the most important role has been in increasing the reservoir quality, and cementation and compaction have been the most important factors in reducing reservoir quality. Sequence stratigraphy studies identified third order sedimentary sequences of the age of Turonian, Late Cenomanian, and Middle Cenomanian, and studied the facies and diagenetic processes within its framework. Correlation of porosity and permeability data of the core showed that the reservoir quality in this formation was influenced by facies and diagenetic processes. So that the microfacies containing the rudist have the highest reservoir quality. Due to the diagenetic processes, sedimentary and porosity and permeability data, the facies shoal and open marine to the land have the best reservoir quality. Manuscript profile
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  8 - Investigating the role of microfacies, depositional conditions and diagenesis on the quality of the reservoir section, Ilam Formation (Santonian-Campanian) in one of the fields in southwestern Iran, Dezful embayment
  Seyedeh Akram  Jooybari Peyman Rezaei Majid Mehdipour
  10.52547/ispg.39683.11.21.16
  20.1001.1.22518738.1400.11.21.3.1
  The Ilam formation is one of the important carbonate oil reservoirs of the Zagros and Dezful embayment basins. In order to identify the microfacies and depositional conditions and diagenesis processes, 100 microscopic thin sections from one well of this reservoir in on More

  The Ilam formation is one of the important carbonate oil reservoirs of the Zagros and Dezful embayment basins. In order to identify the microfacies and depositional conditions and diagenesis processes, 100 microscopic thin sections from one well of this reservoir in one of the Dezful embayment oil fields were evaluated. Porosity and permeability data were used to check reservoir quality. The petrographic study led to the identification of 9 microfacies belonging to the facies belts of lagoon, barier, middle ramp and outer ramp, which were deposited in the homoclinal ramp environment. The most important diagenesis processes identified in Ilam reservoir include cementation, dissolution, fracture, micriteization, stylolitization, and dolomitization. Based on the qualitative classification of the reservoir and Lucia's petrophysical diagrams, the lagoon facies and the middle ramp have an average reservoir status, and the carbonate barier facies and the outer ramp have a weak reservoir status. The reservoir quality of the lagoon and middle ramp facies is related to the existence of interconnected and channel porosities. Due to strong cementation and the presence of unrelated porosity such as mold porosity, the carbonate barier facies has low permeability and has a poor reservoir status. In general, the Ilam Formation in the studied field is in a weak state in terms of reservoir, which can be important in addition to the facies controllers in relation to the lack of expansion of fracture and dolomitization and the excessive expansion of cementation in these facies. Therefore, the Ilam Formation in the studied field has a weak reservoir performance due to diagenetic processes, despite having more shallow sequences than deep ones. Manuscript profile
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  9 - Investigating the reservoir quality of Sarvk formation using multi-resolution graph-based and comparing it with petrographic data in an oilfield of Dezful Embayment
  Seyedeh Akram  Jooybari Payman Rezaee Majid Mehdipour
  20.1001.1.22518738.1401.12.23.2.1
  Sarvak Formation is one of the important carbonate reservoirs in Dezful Embayment. In order to evaluate the reservoir quality of this formation in one of the Dezful Embayment fields, multi-resolution graph-based method was used and compared with petrographic findings. T More

  Sarvak Formation is one of the important carbonate reservoirs in Dezful Embayment. In order to evaluate the reservoir quality of this formation in one of the Dezful Embayment fields, multi-resolution graph-based method was used and compared with petrographic findings. The findings showed that the Sarvak formation in the studied field consists of 8 microfacies belonging to the sub-environments of the lagoon, carbonate bar, middle ramp and outer ramp, which were deposited in a homoclinal ramp environment. The main diagenesis processes affecting this reservoir include cementation, dissolution, fracture, stylolitization, and dolomitization. The results of multi-resolution graph-based analysis led to the identification of 3 electrofacies, EF1 electrofacies had the weakest reservoir parameters and EF3 facies had the best reservoir status. The majority of EF1 microfacies are grainstone microfacies and the majority of EF3 microfacies correspond to wackstone and packstone microfacies. Based on this, it seems that the lagoon sub-environment has a better reservoir condition than other sub-environments, especially the carbonate bar, and this is an important sign of the different performance of diagenesis processes in these sub-environments. In a vertical trend, the highest volume of hydrocarbon column is in the EF3 electrofacies and the lowest is EF1. In general, it can be stated that the use of multi-resolution graph-based analysis and comparison with petrographic findings is a suitable solution for accurate evaluation of the reservoir quality of carbonate reservoirs. Manuscript profile