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      • Open Access Article

        1 - The Study of Overburden Pressure Effect on Cementation Factor in Hydraulic Flow Units of Carbonate Rocks
        حبیب اله  صدیقی
        Abstract Analyze of parameters which influence the petrophysical Properties of reservoir rocks is necessary in dynamic model simulation of reservoirs. According to the relation of cementation factor and reservoir pressure changes, cementation factor is the most effec More
        Abstract Analyze of parameters which influence the petrophysical Properties of reservoir rocks is necessary in dynamic model simulation of reservoirs. According to the relation of cementation factor and reservoir pressure changes, cementation factor is the most effective parameter in water saturation determination in the mentioned model, so the study of the effect of pressure on cementation factor is necessary. In this study, firstly carbonate core samples of a gas reservoir, in the south of Iran was classified by hydraulic flow unit delineation method. Then their cementation factors were determined by Archie equation and best fit curve method at ambient, 800, 2000, 3500, and 5000 psi pressures. The changes in cementation factor values due to increasing overburden pressure were evaluated in each hydraulic flow unit and their relationship with flow zone indicator (FZI) were studied by experimental equations (for 4 flow units 0.95<R2<0.99). In this study a relation between flow zone indicator for each hydraulic flow unit and cementation factor changes, due to the different pressures, were also obtained. The experimental results of studied reservoir cores shows that with increasing flow zone indicator the changes in cementation factors decreases. Manuscript profile
      • Open Access Article

        2 - The Study of Overburden Pressure Effect on Cementation Factor in Hydraulic Flow Units of Carbonate Rocks
        حبیب اله  صدیقی کاظم سعادت محمد رضا  اصفهانی عزت اله  کاظم زاده
        Abstract Analyze of parameters which influence the petrophysical Properties of reservoir rocks is necessary in dynamic model simulation of reservoirs. According to the relation of cementation factor and reservoir pressure changes, cementation factor is the most effec More
        Abstract Analyze of parameters which influence the petrophysical Properties of reservoir rocks is necessary in dynamic model simulation of reservoirs. According to the relation of cementation factor and reservoir pressure changes, cementation factor is the most effective parameter in water saturation determination in the mentioned model, so the study of the effect of pressure on cementation factor is necessary. In this study, firstly carbonate core samples of a gas reservoir, in the south of Iran was classified by hydraulic flow unit delineation method. Then their cementation factors were determined by Archie equation and best fit curve method at ambient, 800, 2000, 3500, and 5000 psi pressures. The changes in cementation factor values due to increasing overburden pressure were evaluated in each hydraulic flow unit and their relationship with flow zone indicator (FZI) were studied by experimental equations (for 4 flow units 0.95<R2<0.99). In this study a relation between flow zone indicator for each hydraulic flow unit and cementation factor changes, due to the different pressures, were also obtained. The experimental results of studied reservoir cores shows that with increasing flow zone indicator the changes in cementation factors decreases. Manuscript profile
      • Open Access Article

        3 - Electro-Facies and Rock Type Comparison in the One of Gas Field’s Kangan, (Iran)
        حیدر صائمی
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Core More
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Core data, Gamma -Ray, Density and Neutron Porosity petrophysical logs of one of the Field’s wells. Rock Types determination can be a practical solution for categorizing reservoir’s facies aiming assesment of reservoir rock’s petrophysical properties and diffrentiating high potential producer zones from low potential ones. Hence clustering method based on Multi Resolution Graph-Based Clustering (MRGC) which is a “Non Parametric” statistical method, of umpteenth near value and graphical presentation of data, was implyed on Neutron Porosity, Density and Gamma-Ray logs to re-construct equivalent electro facies to the ones obtained from core. At the end, final clusters are formed by combining small clusters where five facies were recognized. The used method in this research eleminates the need of repeated coring and leads to a major cost and time saving. More over the Rock Types were also determind by Hydrolic Flow Units method. Hydrolic Flow Units is a method for categorizing the variety of Rocks according to their flowing properties based on geological and physical flow in pore scale. Five Rock Types were determind by this method also, which had good conformity with the ones from previous method in many locations. In some locations of course the results were not as good which could be as a result of non uniform sampling and human error. Manuscript profile
      • Open Access Article

        4 - Electro-Facies and Rock Type Comparison in the One of Gas Field’s Kangan, (Iran)
        حیدر صائمی وحید توکلی حسن  اشراقی
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Co More
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Core data, Gamma -Ray, Density and Neutron Porosity petrophysical logs of one of the Field’s wells. Rock Types determination can be a practical solution for categorizing reservoir’s facies aiming assesment of reservoir rock’s petrophysical properties and diffrentiating high potential producer zones from low potential ones. Hence clustering method based on Multi Resolution Graph-Based Clustering (MRGC) which is a “Non Parametric” statistical method, of umpteenth near value and graphical presentation of data, was implyed on Neutron Porosity, Density and Gamma-Ray logs to re-construct equivalent electro facies to the ones obtained from core. At the end, final clusters are formed by combining small clusters where five facies were recognized. The used method in this research eleminates the need of repeated coring and leads to a major cost and time saving. More over the Rock Types were also determind by Hydrolic Flow Units method. Hydrolic Flow Units is a method for categorizing the variety of Rocks according to their flowing properties based on geological and physical flow in pore scale. Five Rock Types were determind by this method also, which had good conformity with the ones from previous method in many locations. In some locations of course the results were not as good which could be as a result of non uniform sampling and human error. Manuscript profile
      • Open Access Article

        5 - Electro-Facies and Rock Type Comparison in the One of Gas Field’s Kangan, (Iran)
        حیدر صائمی وحید توکلی حسن  اشراقی
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Co More
        Abstract Kangan Formation in the Study Area is about 444 meters thick and is mainly composed of Limestone and dolomite with randome interbeds of Anhydrites. In this article, Rock Types are determind by Electro Facies and Hydrolic Flow Units (HFU) method using the Core data, Gamma -Ray, Density and Neutron Porosity petrophysical logs of one of the Field’s wells. Rock Types determination can be a practical solution for categorizing reservoir’s facies aiming assesment of reservoir rock’s petrophysical properties and diffrentiating high potential producer zones from low potential ones. Hence clustering method based on Multi Resolution Graph-Based Clustering (MRGC) which is a “Non Parametric” statistical method, of umpteenth near value and graphical presentation of data, was implyed on Neutron Porosity, Density and Gamma-Ray logs to re-construct equivalent electro facies to the ones obtained from core. At the end, final clusters are formed by combining small clusters where five facies were recognized. The used method in this research eleminates the need of repeated coring and leads to a major cost and time saving. More over the Rock Types were also determind by Hydrolic Flow Units method. Hydrolic Flow Units is a method for categorizing the variety of Rocks according to their flowing properties based on geological and physical flow in pore scale. Five Rock Types were determind by this method also, which had good conformity with the ones from previous method in many locations. In some locations of course the results were not as good which could be as a result of non uniform sampling and human error. Manuscript profile
      • Open Access Article

        6 - Microfacies and palaeoecology of the Asmari Formation in southeast flank of the Khami anticline (east of Gachsaran) and Correlation with two other sections of the Asmari Formation in the Zagros Basin
        همتا رنجبر علی رحمانی
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification More
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification 12 microfacies (nummulitidae lepidocyclina packestone/rodestone, corallinacea benthic foraminifera (perforate) packstone, bioclast neorotalia packestone, ooid grainstone, bioclast grainstone, miliolid neorotalia nummulitidae packestone, miliolid corallinacea coral floatstone/grainstone, bioclast benthic foraminifera (imperforate) packstone/grainstone, miliolid packstone/grainstone, sandy mudstone, intraclast mudstone) that deposited in continental slope, shoal, lagoon and tidal flat. In three different salinity facies environment from 34 psu to over 50 psu in oligoophotic to euphotic environment and oligotrophy-weak mesotrophy to eutrophy conditions in a homoclinal carbonate ramp platform recognized for the Asmari Formation at this study area. Correlation of the Asmari Formation in 3 section, A water salinity environmental correlation of the Asmari Formaion from Firozabad to east and north of Gachsaran reveals that 1- during Rupelian the Asmari Formation deposited in a normal water salinity environment, 2- while normal salinity water condition prevailed in Gachsaran area during Chattian, the Fars area was under higher marine salinity environment. Higher salinity environment developed during Aquitanian and Burdigalian in Gachsaran area. Manuscript profile
      • Open Access Article

        7 - Microfacies and palaeoecology of the Asmari Formation in southeast flank of the Khami anticline (east of Gachsaran) and Correlation with two other sections of the Asmari Formation in the Zagros Basin
        همتا رنجبر علی رحمانی
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification More
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification 12 microfacies (nummulitidae lepidocyclina packestone/rodestone, corallinacea benthic foraminifera (perforate) packstone, bioclast neorotalia packestone, ooid grainstone, bioclast grainstone, miliolid neorotalia nummulitidae packestone, miliolid corallinacea coral floatstone/grainstone, bioclast benthic foraminifera (imperforate) packstone/grainstone, miliolid packstone/grainstone, sandy mudstone, intraclast mudstone) that deposited in continental slope, shoal, lagoon and tidal flat. In three different salinity facies environment from 34 psu to over 50 psu in oligoophotic to euphotic environment and oligotrophy-weak mesotrophy to eutrophy conditions in a homoclinal carbonate ramp platform recognized for the Asmari Formation at this study area. Correlation of the Asmari Formation in 3 section, A water salinity environmental correlation of the Asmari Formaion from Firozabad to east and north of Gachsaran reveals that 1- during Rupelian the Asmari Formation deposited in a normal water salinity environment, 2- while normal salinity water condition prevailed in Gachsaran area during Chattian, the Fars area was under higher marine salinity environment. Higher salinity environment developed during Aquitanian and Burdigalian in Gachsaran area. Manuscript profile
      • Open Access Article

        8 - Microfacies and palaeoecology of the Asmari Formation in southeast flank of the Khami anticline (east of Gachsaran) and Correlation with two other sections of the Asmari Formation in the Zagros Basin
        همتا رنجبر علی رحمانی
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification More
        Abstract In order to characterize the features of facies and depositional environment conditions of the Asmari Formation in southeast flank of the Khami anticline with a thickness of 270 m has been studied. the Field and laboratory studies, led to the identification 12 microfacies (nummulitidae lepidocyclina packestone/rodestone, corallinacea benthic foraminifera (perforate) packstone, bioclast neorotalia packestone, ooid grainstone, bioclast grainstone, miliolid neorotalia nummulitidae packestone, miliolid corallinacea coral floatstone/grainstone, bioclast benthic foraminifera (imperforate) packstone/grainstone, miliolid packstone/grainstone, sandy mudstone, intraclast mudstone) that deposited in continental slope, shoal, lagoon and tidal flat. In three different salinity facies environment from 34 psu to over 50 psu in oligoophotic to euphotic environment and oligotrophy-weak mesotrophy to eutrophy conditions in a homoclinal carbonate ramp platform recognized for the Asmari Formation at this study area. Correlation of the Asmari Formation in 3 section, A water salinity environmental correlation of the Asmari Formaion from Firozabad to east and north of Gachsaran reveals that 1- during Rupelian the Asmari Formation deposited in a normal water salinity environment, 2- while normal salinity water condition prevailed in Gachsaran area during Chattian, the Fars area was under higher marine salinity environment. Higher salinity environment developed during Aquitanian and Burdigalian in Gachsaran area. Manuscript profile
      • Open Access Article

        9 - Wellbore Stability Analysis During Drilling Using Geomechanical Model and FLAC3D Software in Asmari Reservoir, Ahwaz Oil Field
        Mohammad میرانی
        Abstract Oil reservoirs are one of the important sources of energy due to which is caused by specific rock mechanical properties, the ability to maintain hydrocarbon fluids. One of the major problems that are occurred during drilling a well is instability of the well More
        Abstract Oil reservoirs are one of the important sources of energy due to which is caused by specific rock mechanical properties, the ability to maintain hydrocarbon fluids. One of the major problems that are occurred during drilling a well is instability of the wellbore. In order to prevent this difficulty its need to predict stability of the rocks by using geomechanical properties and in-situ stresses. A lack of accurate wellbore stability analysis brings many problems such as borehole washout, breakout, collapse, stuck pipes and drill bits. In the present research work the stability of an oil well located in Asmari reservoir of Ahwaz oil field was stimulated by using numerical software FLAC3D and information obtained from well log curves were evaluated and analyzed in two parts and the results were presented. Mud pressure and mud weight in outset of wellbore plastic flow and also outset of shear failure in wellbore were obtained for 7.5 meter of formation which mainly consists of limestone, marl. Well stability analysis was performed in vertical direction, minimum horizontal stress and maximum horizontal stress. Due to plastic movement and shear failure in wellbore, in first stage the mud pressure occurred is 33 and 26.4 Mpa and the second stage it reaches to 45 and 30 Mpa, respectively.It indicates that tensile failure is in direction of maximum horizontal stress and shear failure in direction of minimum horizontal stress. Subsequently, the result shows that the analysis due to the low mechanical properties of the sandstone layer indicates the maximum amount of displacement and loss. The safe mud window is small in this layer. Manuscript profile
      • Open Access Article

        10 - A comprehensive study of shale intervals of Burgan Formation: implications for borehole stability
        Mohammad سلیمانی سعیده رعیت دوست
        Abstract This aims of this study is to characterize the Shale intervals of Burgan Formation from a borehole stability point of view. This paper describes the process and workflow for data-acquisition and interpretation in a shale formation characterization program an More
        Abstract This aims of this study is to characterize the Shale intervals of Burgan Formation from a borehole stability point of view. This paper describes the process and workflow for data-acquisition and interpretation in a shale formation characterization program and demonstrates not only the benefits of acquiring specific data, but also highlights the uses of the data to aid the exploration decision process. The next purpose of this paper is to provide a research process that can be applied in similar geological settings. In the study process, we collected a complete set of information and samples from the field and presented a detailed case study, including laboratorial studies of formation samples and interpretation of the information. Available samples and information sources from Burgan Formation include drillhole cores. The minerals were defined by direct and indirect methods. Bulk XRD analyses performed on core samples showed presence of traces of clay minerals. For determination of the exact clay mineral type, clay minerals were extracted and treated by heat and ethylene glycol saturation. Treated samples were subjected to XRD analyses. Interpretation of the natural gamma spectrometry logs allowed the determination of the type and content of clay minerals. In a next step, in order to study the distribution of minerals types, SEM photomicrographs and Cation exchange capacity (CEC) of the samples were carried out. The results revealed that shale intervals of Burgan Formation are not expandable clays. The instability problem cannot be completely solved by drilling fluid design. The study shows, different approached methods reached the same results. Manuscript profile
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        11 - Application of Kuster and Toksoz equations in inverse modeling technique to estimate the percentages of pore types in carbonate rocks
        اصغر نادری مصطفی حیدری ایرج مداحی ناصر کشاورز فرج خواه
        The most prominent parameter of seismic studies is seismic wave velocity. This parameter is influenced by different factors such as rock properties (Compaction, age, Lithology, Porosity, Pore Shape and etc), fluid properties (Viscosity, Density, fluid type, Saturation) More
        The most prominent parameter of seismic studies is seismic wave velocity. This parameter is influenced by different factors such as rock properties (Compaction, age, Lithology, Porosity, Pore Shape and etc), fluid properties (Viscosity, Density, fluid type, Saturation) and environment (Stress history, Depositional environment, production history, temperature, pressure, etc). Therefore, by identification, study and investigation of the relationship between seismic velocity and these parameters, properties of rock, fluid and environment from seismic data can be inferred. The main factors affecting these parameters are the porosity and pore ambiences. Many studies have been conducted to obtain and understand these relations. Most of the theoretical equations haven’t considered changes in seismic properties from pores. Therefore, the seismic inversion, AVO and pore volume calculated based on these equations, include much uncertainties. One of the equations that consider several factors such as porosity, pore type, mineralogy and pore fluid is provided by Kuster and Toksoz. In this study, using this equation and inverse modeling technique, geometry and pore type and percentage of any type of pore shape in 3 wells penetrated one Irainain hydrocarbon reservoir were estimated. In this reservoir, Spherical and Disk shape have the highest percentage. Manuscript profile
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        12 - Petrophysical evaluation and determination of reservoir rock types in the Ghar member,the Abouzar oilfield, Persian Gulf.
        مهرناز نصیری محمدرضا رجلی نوده
        This study is aimed at petrophysical evaluation of the Ghar reservoir using Multimin method by Geolog software in five wells from the Abouzar oilfield. For this purpose, well log data comprising of neutron, density, sonic, gamma, resistivity and photoelectric absorption More
        This study is aimed at petrophysical evaluation of the Ghar reservoir using Multimin method by Geolog software in five wells from the Abouzar oilfield. For this purpose, well log data comprising of neutron, density, sonic, gamma, resistivity and photoelectric absorption were utilized and their analysis lead to determination of quantitative petrophysical properties such as porosity, volume of shale, water, oil saturation and qualitative parameters including lithology and clay mineral types. The analyses revealed that three zones could be identified in the Ghar reservoir. Meanwhile, there are three shaly interlayers within the Ghar foemation. By application of the cutoff values on oil in place (OIP), petrophysical properties were determined zone by zone and based on Net to Gross ratio (N/G) high reservoir quality zone was identified. Finally by using clustering algorithm, reservoir rock types were identified based upon six properties including density, neutron, gamma ray, volume of shale, water saturation and effective porosity. The facies were introduced on the basis of their priority in reservoir quality so that there is an agreement between petrophysical evaluation results and electrofacies. General lithology of the reservoir in composed of upper loose sands and consolidated sand in the lower part. The lower sands are consolidated by the calcite cement. Overall, the volume of clay minerals in the lower part is less than that of upper part. However, productive zones were separated by a thin shaly layer. The clay minerals type in the shaly layer differs from those present in the reservoir rocks. Total and effective porosity are almost identical which is due to low volume of shale. Manuscript profile
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        13 - Secondary porosity index effect on improving approaches permeability estimation from petrophysical logs utilizing artificial intelligent
        سجاد کاظم شیرودی مرتضی خانیان
        Abstract Permeability estimation using core data and petrophysical logs is a conventional approach which bears high uncertainty especially in carbonate reservoir characterization. In essence, the problem consists not only due to coring expenses rate, but also ambig More
        Abstract Permeability estimation using core data and petrophysical logs is a conventional approach which bears high uncertainty especially in carbonate reservoir characterization. In essence, the problem consists not only due to coring expenses rate, but also ambiguity in finding proper explicit log correlation to core data. Moreover, utilizing the correlated formula in wells without core data can pose errors. In this research the permeability was estimated from conventional petrophysical logs and it was calibrated with permeability obtained from core lab experiments. Applied intelligent systems are the matter of this research for permeability values estimation. To construct permeability estimation model, three techniques have been applied including conventional ANN, the Gonzalez, and Hambalek fuzzy logic techniques. These methods were applied in two wells drilled in Surmeh reservoir in Balal field to establish ANN and to derive a relation between core and well. The models were applied in control well in order to check the reliability and capability of models to estimate representative permeability value. The result showed however three foresaid techniques for permeability estimation were successful the secondary porosity distributed the correlation due to its reduction effect on permeability so that they were not interconnected. Therefore this effect was omitted using secondary porosity index in which the permeability estimation were improved and were estimated close to core value. Manuscript profile
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        14 - Determining Geological, Environmental and Economical Impact Weight for Oil Field Prioritization to Implement Smart Well Technology
        تورج بهروز سید مهدیا مطهری مهدی ندری پری
        Deep oil reservoirs with high heterogeneity need thorough management to maximize production and recovery along with minimizing OPEX and CAPEX. This management is integration between technology, human resource and processes. Smart Well technology helps oil companies t More
        Deep oil reservoirs with high heterogeneity need thorough management to maximize production and recovery along with minimizing OPEX and CAPEX. This management is integration between technology, human resource and processes. Smart Well technology helps oil companies to meet aforementioned goals. Since smart well technology imposes high initial expenditure it is a risky and costly decision for oil companies to apply it for all companies. Indeed, this fact dictates prioritization of oil fields based on several parameters to decide where this technology should be implemented first. In this paper we present a novel screening technique under Analytical Hierarchy Process (AHP) engine. This technique needs criteria and sub-criteria affecting smart well potential of fields such as Geological, Geographical, Environmental and Economical parameters. In this study, the main components of the four main mentioned parameters have been extracted. All of them weighted according to our objective function. The result of this research would be impact weight of each parameter with respect to each other that can be used an engineering box for making decision among several fields for implementing smart well technology. Manuscript profile
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        15 - Geochemical analysis &petrophysical studies: An approach to clay minerals investigation of E member of Qom Formation, Sarajeh gas field
        عباس دهکار سهیلا اصلانی
        Geochemical and petrophysical studies on E member of Sarajeh Gas field shows presence of different type of clay minerals. Petrography studies along with XRD , SEM and EDX analysis on the present samples, indicate presence of Illite, Chlorite and expandable clay mine More
        Geochemical and petrophysical studies on E member of Sarajeh Gas field shows presence of different type of clay minerals. Petrography studies along with XRD , SEM and EDX analysis on the present samples, indicate presence of Illite, Chlorite and expandable clay minerals. Expandable clays comprise, smectite and mixed layer or interstratified Illite/Smectite (I/S) minerals. Petrophsical studies show Th/K on NGS log in Sarajeh, well 12, composed mainly, Illite, chlorite with minor amount of interstratified Illite/Smectite (I/S). Geochemical studies confirm validity of petrophysical results. The presence of different clay minerals of Qom formation in E member, Sarajeh Gas field, may have significant impact on petrophysical properties of reservoir, and hence affect reservoir productivity as well as cause problem during drilling operations. Manuscript profile
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        16 - Effect of multi-walled carbon nanotubes to improve hydrocarbon wells annular clearance space
        Mohammad سلیمانی سعیده رعیت دوست
        Proper drilling fluids has vital role for achieving to hydrocarbon reservoirs by using Drilling operation. Some important problems such as friction, stuck pipe, slow drilling rate, high torque and drag, lost of materials, density variation of mud can be happened due of More
        Proper drilling fluids has vital role for achieving to hydrocarbon reservoirs by using Drilling operation. Some important problems such as friction, stuck pipe, slow drilling rate, high torque and drag, lost of materials, density variation of mud can be happened due of poor hole annulus and cuttings down falling that induce expensive drilling. Various drilling fluids have been widely used in the wells drilling to improve lifting capacity of drilled cuttings. In this paper, the experimental results have been studied that conducted on effect of Multiwall Carbon Nano tubes (MWNTs) as additives for lifting capacity of water based mud. The effect of Useful parameters such as amount of MWNTs used, cutting size and mud annular velocity on the drilling fluid cleaning capacity have been studied. The results show that lifted cuttings increase as the amount of MWNTs added increases. MWNTs associated with water based mud displays the stability against base mud since surface forces easily balance the gravity force and attached to drilled cuttings, resulting in increase of drag force acts to drilled cuttings and easily lifted cuttings to the surface. The MWNTs also will improve viscosity which will significantly increase carrying capacity of the mud. For small and medium cuttings, the improvement relatively simplified compare to the big cuttings. The impact will significantly Manuscript profile
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        17 - Using information entropy theory and bayesian decision method to identify appropriate parameters for evaluating and discriminating oil facies (mansuri oil field, south of Iran)
        حسین معماریان
        Due to subsurface heterogeneity and existing vagueness in geophysical interpretation, identifying and interpretation of facies in wellbores is always prone to uncertainty and risk. Nowadays several methods have developed for quantitative facies interpretation. These met More
        Due to subsurface heterogeneity and existing vagueness in geophysical interpretation, identifying and interpretation of facies in wellbores is always prone to uncertainty and risk. Nowadays several methods have developed for quantitative facies interpretation. These methods are generally divided into deterministic and stochastic categories. Deterministic methods, in spite of their simple modeling procedure, cannot expose the amount of error or accuracy of the model. On the other hand, stochastic methods, in addition to quantifying the error of the model, can provide the probability of the model’s accuracy in each point of the reservoir. The Bayesian approach is one of the stochastic methods that use conditional probabilities for modeling. This approach, as well as probabilistic modeling of hydrocarbon facies, quantitatively computes the effect of additional data in decreasing the error of the classification. Information entropy theory, by quantifying the intrinsic uncertainty in each model input parameter, can easily provide the selection of valuable parameters. The present study was carried out on one of the wells of Mansuri oil field, south of Iran. After generation of training data by using rock physics techniques and Gassmann’s relation, the value of each input parameter was identified by entropy analysis. Then, by use of Bayesian analysis and valuable parameters, oil facies classification and discrimination was implemented. The five optimum parameters were elastic impedance, compressional wave velocity, shear wave velocity, density and porosity .The amount of error in this method is approximated to be 11 percent. This investigation also showed that gamma ray parameter does not have a drastic positive effect on identification and discrimination procedure of oil facies, which has a good agreement with the results of entropy analysis . Manuscript profile
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        18 - Sedimentological studies and Petrophysical interpretation: An approach to reservoir characterization of Sarvak formation in the Dalpari oil field
        علی اصغر عنایتی
        The Ilam and Sarvak Formations of Bangestan Grouop are the second important potential reservoirs after Asmari formation in the zagros basin. Integration of petrographical factors and Petrophysical parameters resulted in better understanding of reservoir qualities of More
        The Ilam and Sarvak Formations of Bangestan Grouop are the second important potential reservoirs after Asmari formation in the zagros basin. Integration of petrographical factors and Petrophysical parameters resulted in better understanding of reservoir qualities of these formations. In this study , 250 thin sections were collected and subjected to microfacies and petrography studies. As a result eight microfacies from three sedimentary environments were identified: Lagoonal (L1 ,L2 ,L3),Barrier (B1 ,B2) and Open marine (O1 ,O2 ,O3) and in three different of digenetic environments such as marine, meteoric and burial. This Study shows Sarvak Formation is being formed on Carbonate Rimmed shelf platform. Petrophysical interpretations by using of IP software shows Sarvak reservoir is divided into 3 zones (4, 5, 6). This study reveals that zone 4 contains the best reservoir quality in compare with the others by having (17m) oil column. porosity (more than 8%) and water saturation less than(14%) in this field. There is also decreasing of water saturation in Pay zone 4, but no significant changes has been observed through out zones 5&6. In zone 4, shale volume increases in zones 5&6 (Vsh more than 25%). Crossplot K-Th and K-Pe reveals that Chlorite_Montmorilonite are the dominant clay minerals in this reservoir. Manuscript profile
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        19 - Biomarker study of Asmari Reservoir oil in the oil fields situated in N.E. Dezful Embayment
        علیرضا  بنی اسد
        Masjid-e-Solyman, Haft kel, Par-e-Siah and Naft Safid are productive oil fields which are located in mountain front of NE Dezful Embayment. In this research, in order to Geochemical correlation and Petroleum Systems determination of Asmari oils, a few oil samples were s More
        Masjid-e-Solyman, Haft kel, Par-e-Siah and Naft Safid are productive oil fields which are located in mountain front of NE Dezful Embayment. In this research, in order to Geochemical correlation and Petroleum Systems determination of Asmari oils, a few oil samples were subjected to biomarker studies by GC and GC-MS techniques. Review of biomarkers fingerprints indicate two petroleum systems probably are active in studied oilfields. A major petroleum system that has controlled the hydrocarbon generation, migration and accumulation in all studied oilfields and a younger petroleum system, which has caused mixture of oils with another source in Masjed-Soleyman and Par-e-Siah oilfields, Biomarkers fingerprints, Steranes, Hopanes in addition to the main petroleum system. parameters, Pristane to Phytane ratios and also n- alkane's distributions among the studied oils, indicate that the Asamri oils were produced mainly from a marine and marine-carbonate source rock(s), which has been deposited in an anoxic conditions, with kerogen mainly of Type II with little contribution of terrestrial Kerogen (Type III) and oil samples has a maturity about early oil window without any severe biodegradation. 13C isotope values distribution, presence of Oleannane biomarker and slightly differences - mainly from lithological aspects and maturation levels of oils - of Masjid-Soleyman and Par-e-Siah Oils, reveal that, the mixed oils in these two reservoirs have been probably produced from two source rocks, a younger source rock namely Pabdeh Formation (Middle Eocene and Early Oligocene) with less importance of Kazhdumi Formation (Albian) which is the main source rock Manuscript profile
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        20 - Porosity estimation with data fusion approach (Bayesian theory) in wells of Azadegan oil field, Iran
        رویا خضرلو هادی کرمانشاهی
        Porosity is one of the main variables in evaluating the characteristics of an oil field. Petrophysical data are normally used to determine these variables. Measurements obtained from well logs, containes some errors and uncertainty. This porosity is influenced by dif More
        Porosity is one of the main variables in evaluating the characteristics of an oil field. Petrophysical data are normally used to determine these variables. Measurements obtained from well logs, containes some errors and uncertainty. This porosity is influenced by different factors, such as temperature, pressure, fluid type, clay content and the and amount of hydrocarbons. One of the best, and yet most practical ways to reduce the amount of uncertainty in porosity measurement is using various sources of data and data fusion techniques. Data fusion increase certainty and confidence and reduce risk and error in decision making. In this research, the porosity is estimated in 4 wells of Azadegan oil field, with data fusion method (Bayesian theory). To check the ability of generalization of the method, the porosity was also estimated in one other well of this field. A maximum of 7 input variables were used to estimate porosity in this new approach. The results showed that data fusion technique is more powerfull than traditional tecniques for porosity estimation. According to the results, this method has higher credibility than traditional techniques that show 0.7 to 0.8 regressions with log data but data fusion technique showed solidarity over 0.9 with log data. Manuscript profile
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        21 - Fractures systematic analysis Asmari reservoir Formation in the Marun oil field (based on image logs interpretation results)
        فارسی مدان arsimadan
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologist More
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologists.. Marun oil field is one of the largest oil fields in the South West Iran of the city of Ahvaz in the Northeast and the North embayment Dezful of geology in the eastern. Marun field is the most important Asmari reservoir. The aim of this study was to investigate systematically Asmari reservoir fractures and the development of fractures in the reservoir. For this purpose, using image logs, best and most complete method interpretation and results of 11 wells in fracture studying and 16 wells in in-situ stress direction studying. According to frequency of fractures (based on image logs interpretation results) in the southern and north-eastern limb of the field, The theory of tectonic folding and bending events later caused the possible activities during the north-south strike-slip faults affect the compression force has been created to strengthen. Most of image logs data in Marun field are fractures with extensions; N155E, N130E, N95E, N60E, N30E. Manuscript profile
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        22 - Sedimentological studies and Petrophysical interpretation: An approach to reservoir characterization of Sarvak formation in the Dalpari oil field
        Abolhasan Ahan kar Abolhasan Ahan kar
        The Ilam and Sarvak Formations of Bangestan Grouop are the second important potential reservoirs after Asmari formation in the zagros basin. Integration of petrographical factors and Petrophysical parameters resulted in better understanding of reservoir qualities of t More
        The Ilam and Sarvak Formations of Bangestan Grouop are the second important potential reservoirs after Asmari formation in the zagros basin. Integration of petrographical factors and Petrophysical parameters resulted in better understanding of reservoir qualities of these formations. In this study , 250 thin sections were collected and subjected to microfacies and petrography studies. As a result eight microfacies from three sedimentary environments were identified: Lagoonal (L1 ,L2 ,L3),Barrier (B1 ,B2) and Open marine (O1 ,O2 ,O3) and in three different of digenetic environments such as marine, meteoric and burial. This Study shows Sarvak Formation is being formed on Carbonate Rimmed shelf platform. Petrophysical interpretations by using of IP software shows Sarvak reservoir is divided into 3 zones (4, 5, 6). This study reveals that zone 4 contains the best reservoir quality in compare with the others by having (17m) oil column. porosity (more than 8%) and water saturation less than(14%) in this field. There is also decreasing of water saturation in Pay zone 4, but no significant changes has been observed through out zones 5&6. In zone 4, shale volume increases in zones 5&6 (Vsh more than 25%). Crossplot K-Th and K-Pe reveals that Chlorite_Montmorilonite are the dominant clay minerals in this reservoir. Manuscript profile
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        23 - Biomarker study of Asmari Reservoir oil in the oil fields situated in N.E. Dezful Embayment
        Mahmud Memariani Ali reza Bani asad
        Masjid-e-Solyman, Haft kel, Par-e-Siah and Naft Safid are productive oil fields which are located in mountain front of NE Dezful Embayment. In this research, in order to Geochemical correlation and Petroleum Systems determination of Asmari oils, a few oil samples were s More
        Masjid-e-Solyman, Haft kel, Par-e-Siah and Naft Safid are productive oil fields which are located in mountain front of NE Dezful Embayment. In this research, in order to Geochemical correlation and Petroleum Systems determination of Asmari oils, a few oil samples were subjected to biomarker studies by GC and GC-MS techniques. Review of biomarkers fingerprints indicate two petroleum systems probably are active in studied oilfields. A major petroleum system that has controlled the hydrocarbon generation, migration and accumulation in all studied oilfields and a younger petroleum system, which has caused mixture of oils with another source in Masjed-Soleyman and Par-e-Siah oilfields, Biomarkers fingerprints, Steranes, Hopanes in addition to the main petroleum system. parameters, Pristane to Phytane ratios and also n- alkane's distributions among the studied oils, indicate that the Asamri oils were produced mainly from a marine and marine-carbonate source rock(s), which has been deposited in an anoxic conditions, with kerogen mainly of Type II with little contribution of terrestrial Kerogen (Type III) and oil samples has a maturity about early oil window without any severe biodegradation. 13C isotope values distribution, presence of Oleannane biomarker and slightly differences - mainly from lithological aspects and maturation levels of oils - of Masjid-Soleyman and Par-e-Siah Oils, reveal that, the mixed oils in these two reservoirs have been probably produced from two source rocks, a younger source rock namely Pabdeh Formation (Middle Eocene and Early Oligocene) with less importance of Kazhdumi Formation (Albian) which is the main source rock. Manuscript profile
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        24 - Geochemical investigation of gas condensate from South Pars field in Persian Gulf, Iran.
        Mahmud Memariani Roya khezrlo Hadi kermanshahi
        In this study, in order to determine the geochemical properties of condensates from South Pars Field, 4 samples from Kangan (Early Triassic) and Dalan (Middle- Late Permian) reservoir were subjected to geochemical analyses. Concentration and Identification of biomark More
        In this study, in order to determine the geochemical properties of condensates from South Pars Field, 4 samples from Kangan (Early Triassic) and Dalan (Middle- Late Permian) reservoir were subjected to geochemical analyses. Concentration and Identification of biomarkers and their fingerprint were achieved by successive treatments of condensate samples. These analyses were; i) Mild evaporation of light hydrocarbons, ii) Mild oil topping of samples and iii) Urea adduction. Based on different biomarkers fingerprints, the accumulated condensates were generated from a carbonate-clastic source rock containing organic matters with mainly kerogen type II and little terrestrial inputs, with marine origin, which has been deposited in anoxic conditions. Maturity of condensate indicates, hydrocarbon generation from a source rock with late oil window and early gas generation stage. Further investigations revealed that, gas and condensates were originated from highly reach organic matter, Silurian shales (Sarchahan Formation) deposited in the Fars and offshore of Persian Gulf region. Manuscript profile
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        25 - Fractures systematic analysis Asmari reservoir Formation in the Marun oil field (based on image logs interpretation results)
        Zahra Kamali Mohammad reza Mahdevar meysam farsi madan
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologi More
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologists.. Marun oil field is one of the largest oil fields in the South West Iran of the city of Ahvaz in the Northeast and the North embayment Dezful of geology in the eastern. Marun field is the most important Asmari reservoir. The aim of this study was to investigate systematically Asmari reservoir fractures and the development of fractures in the reservoir. For this purpose, using image logs, best and most complete method interpretation and results of 11 wells in fracture studying and 16 wells in in-situ stress direction studying. According to frequency of fractures (based on image logs interpretation results) in the southern and north-eastern limb of the field, The theory of tectonic folding and bending events later caused the possible activities during the north-south strike-slip faults affect the compression force has been created to strengthen. Most of image logs data in Marun field are fractures with extensions; N155E, N130E, N95E, N60E, N30E Manuscript profile
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        26 - Fractures systematic analysis Asmari reservoir Formation in the Marun oil field (based on image logs interpretation results)
        meysam farsi madan Mohammad reza Mahdevar Zahra Kamali
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologi More
        In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologists.. Marun oil field is one of the largest oil fields in the South West Iran of the city of Ahvaz in the Northeast and the North embayment Dezful of geology in the eastern. Marun field is the most important Asmari reservoir. The aim of this study was to investigate systematically Asmari reservoir fractures and the development of fractures in the reservoir. For this purpose, using image logs, best and most complete method interpretation and results of 11 wells in fracture studying and 16 wells in in-situ stress direction studying. According to frequency of fractures (based on image logs interpretation results) in the southern and north-eastern limb of the field, The theory of tectonic folding and bending events later caused the possible activities during the north-south strike-slip faults affect the compression force has been created to strengthen. Most of image logs data in Marun field are fractures with extensions; N155E, N130E, N95E, N60E, N30E. Manuscript profile
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        27 - Correction of measured vitrinte reflectance data using the "Fluorescence Alteration of Multiple Macerals" (FAMM) and their application to Well Binak #4 one-dimensional thermal maturity modeling
        Mohammad KassaieNajafi Faramarz Shabani Maryam Mirshahani Beyok Ghorbani Arsalan Zenalzadeh
        Reflectance of maceral constituents of kerogens, particularly vitrinite (Ro%), commonly used in petroleum exploration, is a very important indicator for determining degree of thermal maturity and investigating status of hydrocarbon generation. Although in vitrinite r More
        Reflectance of maceral constituents of kerogens, particularly vitrinite (Ro%), commonly used in petroleum exploration, is a very important indicator for determining degree of thermal maturity and investigating status of hydrocarbon generation. Although in vitrinite reflectance profiles maturity generally increases with increasing depth of burial, basin modelers often experience problems when modeling thermal maturity using vitrinite reflectance data measured by using reflected light- photometer microscopes. The problem of reduced vitrinite reflectance mainly arises due to reflectance suppression in vitrintes. By using the laser Raman microprobe, a new multi-parameter technique called "Fluorescence Alteration of Multiple Macerals (FAMM)" was developed by Australian scientists to solve these problems. In this study, data obtained by application of this method were used to correct suppressed vitrinite reflectance values. In order to examine and demonstrate the extent of suppression effect on modeling results, maturity profile constructed by one-dimensional modeling of Well Binak-4 was calibrated using conventional measured vitrinite reflectance (Ro%) and FAMM equivalent vitrinite reflectance (EqVR) data and results were compared with present time measured well temperatures. The crucial differences in maturation, transformation ratio, hydrocarbon generation and expulsion resulted from application of these two type data as calibration parameters are discussed and demonstrated using relevant diagrams. Manuscript profile
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        28 - Geochemical study of Tar-mat formation in Bangestan reservoir in Kupal oil field
         
        Kupal anticline is elongated and almost symmetric. This structure is located in Northwest of Ahwaz city and consists of two reservoir including Bangestan and Asmari. Kazhdumi, Pabdeh and Gurpi formations are probable source rocks and Gachsaran Formation constitutes the More
        Kupal anticline is elongated and almost symmetric. This structure is located in Northwest of Ahwaz city and consists of two reservoir including Bangestan and Asmari. Kazhdumi, Pabdeh and Gurpi formations are probable source rocks and Gachsaran Formation constitutes the cap rock. Because project topic is defined on Bangestan Group, so reservoir studies of Bangestan is focused on Sarvak Formation. Rock-Eval and geochemical analyses conducted on source rocks indicated that Pabdeh Formation is at early stage of oil generation window in the Kupal oil field. Kazhdumi Formation has not been drilled at this field, so geochemical and maturity assessment of this formation has been evaluated using samples from adjacent oil fields including Marun and Haftgel. Geochemical analyses indicated that Kazhdumi Formation is mature enough and is considered to be the main source rock. The aim of this project is investigating Tar-mat in Bangestan reservoir in Kupal field. It is thought that Tar-mat layer was formed in vicinity of oil-water contact and can be related to processes including natural deasphaltening, gravity segregation and oil-mixing. Based on Rock-Eval pyrolysis, pyrolysis-GC performed on Sarvak oil, it is suggested primary asphaltene formed from source rock does not exist in the studied oil but it is derived from secondary asphaltene by chemical reactions occurring due to oil-mixing in production well. In addition, analysis performed on asphaltene in oil zone, oil-water contact and water zone suggest that Tar-mat was formed in oil water contact region due to oxidation process. This layer acts as impermeable seal and prevents water flow to oil Manuscript profile
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        29 - The application of clustering methods (MRGC, AHC, DC, SOM) determining permeability carbonate reservoir rocks Ilam Formation in South West Iran
        Seyed Ali Moallemi farhad khoshbakht sakineh naghdi
        The permeability of reservoir parameters is important in the calculation and modeling reservoir plays a role. Measured directly via cores taken from the reservoir layer can be achieved. But due to the limited amount of core taken in a field and laboratory methods as wel More
        The permeability of reservoir parameters is important in the calculation and modeling reservoir plays a role. Measured directly via cores taken from the reservoir layer can be achieved. But due to the limited amount of core taken in a field and laboratory methods as well as high cost; use indirect methods to determine the wells without core permeability is great value. In this study, using clustering methods using petrophysical logs permeability values were measured and analyzed. For this purpose, petrophysical logs Ilam Formation selection of 8 wells and addition of data measured in vitro permeability 3-ring is used to compare the results. Log permeability effective porosity in the well using the parameters A with the core permeability data, estimates and then check the accuracy of estimates, calculations also took place in other fields of study. In the next step, using clustering method, was estimated permeability. Then the results with experimental data and correlation coefficient, the best method is introduced. Manuscript profile
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        30 - Biostratigraphy, sedimentary environment and sequence stratigraphy of the Asmari Formation in well no. 4 of Lab-e Safid oil field (north of Dezful embayment, SW of Lurestan) and Tang- e Lendeh (Kuh-e Safid, NW of Dehdasht)
        Selahedin Arab pour Ali Seyrafian Ali Rahmani
        In this research biostratigraphy, microfacies, sedimentary environment and sequence stratigraphy of the Asmari Formation in well no.4 of Lab-e Safid (north of Dezful embayment, SW of Lurestan) and Tang- e Lendeh (Kuh-e Safid, NW of Dehdasht) has been studied. The tota More
        In this research biostratigraphy, microfacies, sedimentary environment and sequence stratigraphy of the Asmari Formation in well no.4 of Lab-e Safid (north of Dezful embayment, SW of Lurestan) and Tang- e Lendeh (Kuh-e Safid, NW of Dehdasht) has been studied. The total thickness of the Asmari Formation is 360 m and 260 m in the Lab-e Safid and Tang- e Lendeh sections, respectively and composed of thick, medium and thin bedded limestone. The correlation of recognized biozones in the studied regions with other regions in Zagros (Bangestan Anticline: tang-e Band, tang-e Nayab and Tang-e Bulfares, Parsi oil field, Kuh-Asmari and Khaviz Anticline: Tang-e Bibinarjes) indicates that Asmari Formatin in Tang-e Bibinarjes, Tang-e Band and, well no.4 of Lab-e Safid has deposited earlier than other regions. Four different sub environments were identified in the Asmari Formation based on microfacies analysis including tidal flat, lagoon, shoal, open marine. These depositional environments correspond to inner, middle and outer ramp. On the basis of deepening and shallowing patterns in the microfacies five and two third-order sequences have been recognized in the Lab-e Safid and Tang- e Lendeh sections, respectively. In order to study the changes of depositional environment of the Asmari Formation during the Oligocene-Miocene, the recognized sequences in this study have been correlated with those recognized in other parts of the Zagros basin. Manuscript profile
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        31 - 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
        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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        32 - Biostratigraphy and sedimentary environment of Asmari Formation in Davan section, North of Kazerun
        masood khoshnood Hosyen Vaziri moghadam
        This research concentrates on biostratigraphy, microfasies and Sedimentary environment of the Asmari Formation at Davan village in 10 Km north of Kazerun. Micropalaeontological study led to recognition of 25 genera and 15 species of foraminifera. Based on biostratigraph More
        This research concentrates on biostratigraphy, microfasies and Sedimentary environment of the Asmari Formation at Davan village in 10 Km north of Kazerun. Micropalaeontological study led to recognition of 25 genera and 15 species of foraminifera. Based on biostratigraphic study 3 biozones (1-Nummulites vascus – Nummulites fichteli assemblage zone, 2 -Lepdocyclina-Operculina- Ditrupa Assemblage Zone, 3- Archaias asmaricus- Archaias hensoni- Miogypsinoides complanatus Assemblage Zone) are determined. As a result, the age of the Asmari Formation is Oligocene (Rupelian – Chattian) at the study area. Depositional texture, petrographic analyses and fauna led to identification of 9 carbonate microfacies related to open marine, slope, bar and lagoon. These depositional environments correspond to inner, middle, and outer ramp. Manuscript profile
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        33 - Origin of seeping hydrocarbon gases from onshore mud volcanoes in Makran coast of Iran
        Mahin Farhadian Babadi Behzad  Mehrabi Adriano  Mazzini Elena Poludetkina Ata Shakeri
        Mud volcanoes are geological structures formed as a result of gas emission, mud-fluid mixing and variably sized rock fragments in onshore and offshore settings. These structures are different morphologically which considered as significant marker of modern crustal movem More
        Mud volcanoes are geological structures formed as a result of gas emission, mud-fluid mixing and variably sized rock fragments in onshore and offshore settings. These structures are different morphologically which considered as significant marker of modern crustal movement and neotectonic activity. Occurrence of numerous mud volcanoes on the Makran accretionary prisms in Iran and Pakistan are reported which caused by the convergence of the Arabian and the Eurasian plates. In this study, origin of discharged hydrocarbon gases from three active onshore mud volcanoes; Ain, Borborok and Sand Mirsuban in Makran coasts of Iran were examined. The released gases of all these mud volcanoes are dominantly methane with concentration between 97.24-99.18 vol. % and minor amount of ethane (0.04-1.2 vol.%), propane (0.001-0.194 vol.%), n-butane (226 ppmvol.%), iso-butane (5-363 ppmvol.%), n-pentane (37ppmvol.%), iso-pentane (1-66 ppmvol.%), hexane (1-78 ppmvol.%) and CO2 (0.07-0.4 vol.%). Carbon and hydrogen isotope ratio of methane and its heavier derivatives indicate thermogenic source for emitted gases of all investigated mud volcanoes and evidences of the absence of biodegradation. CO2 with carbon isotope ratio of -11.1 to -14.3‰ is organic in origin. Our research suggests the presence of hydrocarbon system and active source rock in Makran active tectonic area. Although the occurrence of an exploitable gas reservoir in this area has to be confirmed by geophysical measurements, geological survey and structural settings. Manuscript profile
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        34 - Study the role of drilling mud loss modeling and FMI log in determining Asmari reservoir fractures in one of the oil fields in Southwest Iran
        Kioumars Taheri Mohammad Reza  Rasaei Abbas Ashjaei
        Understanding of oil and gas reservoirs is of great help in maximizing hydrocarbon recovery. In the study of the characteristics of oil structures, the study of fractures of reservoir rock in the stages of production and development of the field is very necessary. Nowad More
        Understanding of oil and gas reservoirs is of great help in maximizing hydrocarbon recovery. In the study of the characteristics of oil structures, the study of fractures of reservoir rock in the stages of production and development of the field is very necessary. Nowadays, the use of mud loss modeling and image logs in helping accomplish this task is of great assistance to oil geologists. Since the most of Iran's reservoirs are carbonate kind, investigating and identifying fractures, the degree of fissures opening and porosity distribution in the Asmari reservoir field of study, It is one of the most effective factors in the production of hydrocarbons from this field. One of the best ways to identify and interpret geology in the well, using of the FMI image log is, which can create high quality images from the well. With the help of the images provided, can determine the types of fractures, porosity, the distribution of diagenetic porous spaces and the estimation of permeability trend. In this article, first, structure and Functionality of the FMI image log and then drilling and production problems were evaluated in Asmari reservoir. In the following, the functional role of the log in interpreting and determining the degree of fissures opening, porosity distribution and permeability level in 8 wells in Asmari reservoir, has been evaluated. In this study, identification of Asmari reservoir fractures and how to expand these fractures in the reservoir By using mud loss modeling, interpretation of the FMI image log and the effect of these fractures was on the porosity and permeability of the reservoir. In this study, it has been determined that, fractures identified in wells very good matching with drilling mud loss maps with rock basement faults at the has anticline of the Asmari reservoir. Manuscript profile
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        35 - Improve the detection of buried channel, using Artificial Neural Networks and seismic attributes
        Alireza Ghazanfari Abdolrahim Javaherian Mojtaba Seddigh Arabani
        Channels are one of the most important stratigraphic and morphological events. If channels place in a suitable position such as enclosed in impermeable place can make suitable oil and gas reservoir; So identifying channels are crucial. Different tools such as filters, s More
        Channels are one of the most important stratigraphic and morphological events. If channels place in a suitable position such as enclosed in impermeable place can make suitable oil and gas reservoir; So identifying channels are crucial. Different tools such as filters, seismic attributes, artificial neural networks, and meta-attributes have played an important role in this regard. In this paper dip-steering cube, dip-steer median filter, dip-steer diffusion filter, and fault enhancement filter, have been used. Then, various seismic attributes such as similarity, texture, spectral decomposition, energy and polar dip have been defined and studied. Therefore, work on F3 real seismic data of Dutch part of the North sea for detecting channels has been started by detecting suitable attributes. For identifying the channel in data, it has been used from compilation and combination of seismic attributes using supervised ANN (multi-layer perceptron), and development of mata-attributes, then recombine meta-attributes created along the channel, and using different interpretation point, for eliminating the impact of facies and lithology changes along the channel. Among the advantages and the reasons for using this kind of neural network (supervised), which increases the effect of the neural network and improves the result, is the ability to train the network by specifying the channel and non-channel points used in this paper. Finally, using the above methods, the identification of the channel examined in the above seismic data has been improved, and the channel has been properly detected and extracted throughout its entire length. Manuscript profile
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        36 - Calculation of elasticity modulus and rock strength parameters and their relationship with porosity in Dalan formation in one of the well in south pars gas field
        Reza Khoshnevis Zadeh Alireza Hajian Ehsan Larki
        The elastic parameters of the rock include the Young modulus, the Poisson ratio, the bulk modulus and the shear modulus. Young modulus with the unconfined compressive strength of rock, are two key parameters in the definition of intact rock. Elastic modulus represents t More
        The elastic parameters of the rock include the Young modulus, the Poisson ratio, the bulk modulus and the shear modulus. Young modulus with the unconfined compressive strength of rock, are two key parameters in the definition of intact rock. Elastic modulus represents the amount of rock rigidity and is known as the stress-strain chart slope. These parameters represent of rock strength to failure, are important parameters for the stability analysis of wellbore stability. According to the unavailability and cost of core data, and also attended to this fact that the data from the core are not continuous and not available at all points in the well, the uses of DSI logs is one of the best methods for calculating elastic modules. Using these logs, you can also study elastic moduli continuously in a well. In this study, elastic dynamic parameters were calculated using the DSI and density logs for the Dalan Formation. Attention to the fact that the calculated parameters using the velocity of the sound waves are of the type of dynamic parameters, these parameters were have converted to the static modules using appropriate empirical relationships. The rock strength Parameters were calculated using the experimental relationships commonly used in the oil industry to determine rock strength parameters. These parameters were calculated according to static elastic modulus as well as porosity and shale volume. Comparing the values of elastic modulus and rock strength parameters with porosity showed that porosity with elastic modulus and rock strength parameters has an inverse relationship, so that with increases the porosity, the elastic modulus and rock strength parameters have been reduced. Manuscript profile
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        37 - Biostratigraphy and microfacies of the Asmari Formation in Lar anticline (northeast of Gachsaran): biostratigraphical correlation
        Meysam Barari Kharkeshi Ali Seyrafian Hossein Vaziri-Moghaddam Roohollah Shabafrooz
        The Asmari Formation at the Lar anticline, located 77 km northeast of Gachsaran city, comprised 361 meters in thickness. In the present study, biostratigraphy and microfacies of the Asmari Formation at the Lar anticline (northeast of Gachsaran city) is investigated. Bas More
        The Asmari Formation at the Lar anticline, located 77 km northeast of Gachsaran city, comprised 361 meters in thickness. In the present study, biostratigraphy and microfacies of the Asmari Formation at the Lar anticline (northeast of Gachsaran city) is investigated. Based on foraminiferal distribution, 25 genera and 21 species have been identified and four biozones: 1. Lepidocyclina – Operculina – Ditrupa assemblage zone, 2. Archaias asmaricus – Archaias hensoni – Miogypsinoides complanatus assemblage zone, 3. Indeterminate zone, 4. Borelis melo curdica – Borelis melo melo assemblage zone, representing Oligocene (Chattian) to Early Miocene (Aquitanian - Burdigalian) are introduced, respectively. 12 microfacies related to an open marine and lagoon (semi-closed and closed) environments of homoclinal ramp setting are present. Manuscript profile
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        38 - Biostratigraphy of the Gurpi Formation Based on Planktonic foraminifera with emphasis on the Cretaceous-Paleogene boundary in Jahangirabad Section, Kabirkuh Anticline, SW Iran
        Alireza Ashouri Samira Rahimi Abass Sadeghi Abbas Ghaderi
        In this research, biostratigraphy of the Gurpi Formation in Jahangirabad section, SW Iran, has been studied .The thickness of the Gurpi Formation in this section is 263 and consists mainly of argillaceous limestone and limestone. The lower boundary with the Ilam Formati More
        In this research, biostratigraphy of the Gurpi Formation in Jahangirabad section, SW Iran, has been studied .The thickness of the Gurpi Formation in this section is 263 and consists mainly of argillaceous limestone and limestone. The lower boundary with the Ilam Formation is comformable with sharp lithology and upper boundary with the Pabdeh Formation is gradational. In this study, 76 species belong to 17 genera and 8 biozones of planktonic foraminifera were recognized. The biozones consist of Globotruncana ventricosa Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Globotruncana aegyptica Zone, Gansserina gansseri Zone, Contusotruncana contuosa Zone, Abathomphalus mayaroensis Zone and Pseudoguembelina hariaensis. The age of the Gurpi Formation in this section based on these biozones is Middle Campanian to Late Maastrichtian in this section. Manuscript profile
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        39 - Biostratigraphy and microfacies of the Asmari Formation in north flank of Khami anticline (north of Gachsaran)
        Mona Rahim Abadi Hossein Vaziri-Moghaddam Ali Seyrafian farzad Sotohian
        In the present study, biostratigraphy, microfacies and sedimentary environment of the Asmari Formation in north flank of the Khami anticline in the north of the Gachsaran province is investigated. The Asmari Formation at the study section with a thickness of 276 meters More
        In the present study, biostratigraphy, microfacies and sedimentary environment of the Asmari Formation in north flank of the Khami anticline in the north of the Gachsaran province is investigated. The Asmari Formation at the study section with a thickness of 276 meters is a thin, medium and thick to massive limestone, nodular limestone, marl, marly limestone, dolomite and dolomitic limestone. In this study 166 thin sections are studied and 23 genera and 24 species of foraminifera have been identified and 3 biozones are introduced. 1- Archaias asmaricus-Archaias hensoni-Miogypsinoides complanatus Assemblage zone. (Chattian) 2- Indeterminate zone (Aqutanian) 3- Borelis melo curdica-Borelis melo melo Assemblage zone. (Burdigalian) Thus, the age of the Asmari Formation at the study area is Chattian to Burdigalian (Oligo-Miocene). Based on study of thin sections and by considering the sediment texture, distribution of skeletal and non-skeletal grains, 12 microfacies are recognized which were deposited in open marine, bar, semi-restricted and restricted lagoon. Four platform types for the Asmari Formation at the study area in comparison with the recent studies on Asmari Formation including: 1-Rupelian-lower Chattian: Distally steepend ramp, 2-middle Chattian-upper Chattian: open shelf, 3-Aqiutanian: homoclinal ramp, 4-lower Burdigalian: carbonate platform. Manuscript profile
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        40 - Evidence of transpressional tectonics in NW of central Iran sedimentary basins based on reflective data and geomorphic indices
        Mohammad Mokhtari S.Ahmad Alavi Leila Mahshadnia
        The depressed basins of northwest central Iran are located in the structural Step and between Soltanieh-Ipac-Koshk-e-Nosrat and Qom –Zefreh system (the Indes - Qom –Khurabad faults). The main process of deformation within the basin with extension and compression of spec More
        The depressed basins of northwest central Iran are located in the structural Step and between Soltanieh-Ipac-Koshk-e-Nosrat and Qom –Zefreh system (the Indes - Qom –Khurabad faults). The main process of deformation within the basin with extension and compression of specific structures are comparable and verifiable using experimental models. The extensional structures include roll-over folds and normal faults, resulting in deep sedimentary basins during deposition of the lower and upper red formations. The younger structures, includes back-thrusts and for-thrusts, shortcut, and pop up structures represents the reversal of tectonic of primary extensional basin. These sedimentary basins have been created in relation to the growth faults and hanging wall blocks So In the presence of roll-over fold and antithetic and synthetic faults therefore are suitable for entrapment of hydrocarbons during migration. The active structural features have been identified using combination of geomorphic characteristic and seismic reflection data. Accordingly, none of the old normal faults in the Saveh- Qom and Aran basin show at the present any extensional movement and the fault activity of boundary faults and extensional folding are compressional. The active parts are: hanging wall of Saveh, restraining bending at the end of Indes fault that has stream Length-Gradient (SL) index and high value hypsometric index (Hi). The central part of Saveh-Qom and Aran basin, although show high Hi but the SL is low. This situation is due to the moderating effects of the thick lower and upper red formations and evaporative layer within the basin. In the Aran basin due to incomplete coverage of seismic lines the absence of normal faults cannot be definitively confirmed. However, the center of Aran basin as of Qom-Saveh formed push up which marks the compression of this basin and also activity of reverse and thrust faults. Based on the existing surface and subsurface data set, active deformation in this area now is transpression basin and the interior domains are in the uplift. Manuscript profile
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        41 - Reconstruction of sedimentary environment, and depositional sequences based on Microfacies of the Qom Formation in the Kahak area (Southwest of Qom city)
        Mahdiyeh  Mahyad Hosyen Vaziri moghadam
        In this study, sedimentary environment and depositional sequences were reconstructed based on distribution of microfacies in the sequence belong to the Qom Formation in the Kahak area. The formation was formed alternation of shale and limestone. The boundary between the More
        In this study, sedimentary environment and depositional sequences were reconstructed based on distribution of microfacies in the sequence belong to the Qom Formation in the Kahak area. The formation was formed alternation of shale and limestone. The boundary between the Qom Formation and the volcanic rocks is unconformable. In addition, the Upper Red Formation in the Kahak area unconformably overlies the Qom Formation. In the study area, 6 microfacies, and 1 terrigenous facies (shale) for the Qom Formation were identified by study of these rock samples. The Qom Formation was deposited in an open-shelf carbonate platform in the study area. This platform can be divided into two environments that the environments consist of the inner shelf (restricted lagoon and semi-restricted lagoon) and middle shelf. Finally, two third-order sequences were identified based on distribution of microfacies in the Kahak area. Manuscript profile
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        42 - Compilation of artificial neural networks and the thinned Fault likelihood auto-tracking algorithm, for identification, interpretation and extraction of faults
        Alireza Ghazanfari Hoseyn Mohammadrezaei Hamidreza Ansari
        Fault identification and investigating their evolution is of special importance in the exploration and development of hydrocarbon resources. Success in exploration and development of hydrocarbon fields, need to recognition of petroleum systems and in this regard one of More
        Fault identification and investigating their evolution is of special importance in the exploration and development of hydrocarbon resources. Success in exploration and development of hydrocarbon fields, need to recognition of petroleum systems and in this regard one of the most important topics is identifying faults and their extension condition as a main fluid migration path, specially in deeper zones. Faults and fractures have crucial role in making high permeable and porous segments and cut reservoir and cap rock in the fluid migration path. In addition, for maximizing the production of hydrocarbon from reservoirs and also for reducing the risk of drilling, it is necessary to gain information about geometry and nature of faults of reservoirs. In this paper, the purpose is investigating the performance of combination of neural networks and Fault Likelihood auto-tracking algorithm for identification and interpretation of faults in seismic data. At first using the Dip-steering feature of software, the early filter for accurate identification of dip of structures in the data, have been designed and applied. Then with designing and applying the appropriate filters, the seismic data have been improved. After that proper seismic attributes for fault identification have been calculated from seismic data. With picking fault and non-fault points from data, a supervised neural network using the selected attributes was formed and after training the network, the appropriate output achieved. Then the output of neural network has been used as a input for Thinned Fault Likelihood auto-tracking algorithm. The output of this part contains a volume of tracked faults. Finally using sub-tools of TFL and optimal setting of parameters, 3D fault planes has been interpreted and extracted. Manuscript profile
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        43 - Integrated different methods (Lorenz, Lucia, Amaefule) in rock types and flow units identification of lower Miocene Razak Formation at Sarkhun gas field, Zagros basin, SE Iran
        Mohammad Hossein Saberi Milad Karampour.Hasanvand Seyed Ali Moallemi
        One of the most important stages in the hydrocarbon reservoirs morphology is the identification of rocky type. In order to construct an efficient and correct model of a hydrocarbon reservoir, identification of rock types is one of the essential parameters in reservoir m More
        One of the most important stages in the hydrocarbon reservoirs morphology is the identification of rocky type. In order to construct an efficient and correct model of a hydrocarbon reservoir, identification of rock types is one of the essential parameters in reservoir modeling. and its consequences are found in the identification of rock types. The aim of this study is to compare different methods of determining rocky type and understanding the hydraulic flow unit distributions in order to assess the quality of reservoir of Razak Formation with sandstone carbonate lithology, marl and anhydrite to San Oligocene to lower Miocene. In this research, the experimental results of porosity, permeability and capillary pressure curves for 84 samples with porous microscopic sections Related to a 46-meter drill bit in one of the important fields of southeast of Iran were analyzed. The petrographic studies were conducted to investigate the changes of the features in the reservoir section with Razak formation and resulted in the identification of eight microfeatures( The MF1 packstone and Wackstone are at a depth of 2829 meters- The MF2 is the grinstone packstone at a depth of 2844 meters-the MF3 is the wackstone mudstone at a depth 2856 meters-the MF4 is the grinstone at a depth 2859meters –the MF5 is the mudstone wackstone are at a depth2848 meters – the MF6 mudstone at a depth of 2838 meters the MF7is the wackstone mudstone at a depth 2840 meters- The MF8 is a wackstone with sandstone depth of 2831) meters- in open Marin lagoon and fluvial clastic systems. In order to determine the rocky species and assess the flow units based on the core analysis results, four petrophysical classes were identified using the Lucia method. The petrophysical category number 1 has the best reservoir quality and the fourth category has the weakest reservoir quality. Also, the flow units were identified and separated using Amalufee and Lorenz's methods. Based on the Amalufee method, in the reservoir section of the Razak Formation, seven flow units have been identified, the sixth and seventh stream units were the best and one was the weakest reservoir segments among the seven units of the flow. Also, based on the analysis of capillary curves, six rocky species were distinguished, based on which the rocky type number five and six have the best quality. Also, using Geology software cross-sections, it was revealed that the main part of this section is sandstone with clay. The presence of gas in the formation causes cross-sectional deformation of samples to the northwest cross-platform. Finally, with the combination of various data, it was found the fossil formation in the study area has five types of rock in which the number 4 rock has the best quality of reservoir and rock number 5 has the largest reservoir and the unit number six is the best. Manuscript profile
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        44 - Analysis Correlation of Seismo-Tectonic in Bakharden-Quchan Zone with Geometry Disorders of Earthquakes
        Javad Biglari abbas kangi abdolreza jafarian
        The most seismic activities have observed around and along major fault systems of this zone in NE Iran that involving of an array active right lateral-strike slip faults have distributed by trending NW-SE. neotectonic activity and mechanism changing of faults to reverse More
        The most seismic activities have observed around and along major fault systems of this zone in NE Iran that involving of an array active right lateral-strike slip faults have distributed by trending NW-SE. neotectonic activity and mechanism changing of faults to reverse trusting faults have caused to increase stress, shortening and increasing seismicity with high density of earthquakes in their ends bending. Structural relation faults between this zone and Binaloud through Meshkan thrusting-transfer zone which is major motion engine of Bakharden-Quchan zone to put it constantly under neotectonic stresses convergence of Arabia-Eurasia plates since last phase Alpine orogeny. In this paper Fractal analysis through box counting method has done and D values change between 0-2. If D closes to zero, faults an earthquakes are focusing in a point with high tension and if D closes to 2 is shown low tension, dispersal faults and earthquakes in whole of region. Both surface/volume fractal dimension distribution show higher seismicity activity in Central and Western parts of Kopeh Dagh in NE Iran. Manuscript profile
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        45 - Investigation of main planktonic foraminifera bio-events at the base of the Coniacian and Santonian stages in the Surgah Formation, Maleh-Kuh and Sarkan wells, South west of Khoram Abad
        Mohammad Hadadi Meysam Shafiee Ardestani Mohammad Vahidinia Mohammad Gharaee
        In this study Surgah Formation at Maleh-Kuh and Sarkan section in south west of Khoram Abad have been studied based on bio-event models. Surgah Formation at Sarkan well no.1and Maleh-Kuh has 46 and 82-meter thickness respectively and was placed on the Sarvak Formation a More
        In this study Surgah Formation at Maleh-Kuh and Sarkan section in south west of Khoram Abad have been studied based on bio-event models. Surgah Formation at Sarkan well no.1and Maleh-Kuh has 46 and 82-meter thickness respectively and was placed on the Sarvak Formation and under the Ilam Formation. In this study Surgah Formation were composed of shale, limy shale with glauconite and pyrite. In this section two Turonian-Coniacian and Coniacian-Santonian boundaries were recognized in Dicarinella concavata Interval Zone. Based of Heterohelix moremani and FODs Dicarinella concavata and Dicarinella primitiva were detected Turonian-Coniacian boundary. Finally based on LoDs Dicarinella primitiva and Marginotruncana marginata were distinguished Coniacian - Santonian boundary in this section. Manuscript profile
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        46 - Modeling of Horizontal Extent of Pay zone Layer on the Basis of Petrophysical Parameters Variations Using Indicator Kriging Method in one of the Southwest Iranian Oil Fields
        Farnaz Saberi Farhad Mohammad Torab Kioumars Taheri
        Determining the position of the production zone is one of the best ways to reduce drilling costs as well as quick access to the reservoir and optimal production of hydrocarbon resources. The purpose of this study, is to estimate the porosity, water saturation and thickn More
        Determining the position of the production zone is one of the best ways to reduce drilling costs as well as quick access to the reservoir and optimal production of hydrocarbon resources. The purpose of this study, is to estimate the porosity, water saturation and thickness of an oil field in Iran’s southwestern Basin , and ultimately to reach the production zone. Therefore, according to the data obtained from 76 wells of this field, variation of reservoir petrophysical parameters were modeled with variogram operation and using Geostatistical methods. By using ordinary Kriging method, the values of the parameters were estimated in the whole field. Subsequently, by using the indicator kriging method, the field boundaries were separated in order to obtain the exact area of the oil zone and the volume of oil in place and finally by considering the 80% probability level, The definite boundary of the presence of the production zone was determined in the block model and In this zone the volume of reservoir’s hydrocarbon was estimated about 147/5 million cubic foot. Manuscript profile
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        47 - Occurrence of heavy crude oil in the Persian Gulf
        Ali reza Bashari
        Some of the most prolific petroleum reservoirs with high gravities of oil in the world occured in the Upper Jurassic and Cretaceous carbonate formations in the Persian Gulf area .Most of the reservoirs are composed of pelletal,oolitic ,or bioclastic grai More
        Some of the most prolific petroleum reservoirs with high gravities of oil in the world occured in the Upper Jurassic and Cretaceous carbonate formations in the Persian Gulf area .Most of the reservoirs are composed of pelletal,oolitic ,or bioclastic grainstones and reefal limestone that have high primary porosity and permeability .These reservoirs are sealed either by tight limestone ,massive anhydrite, or by impermeable rocks. The seals are effective throughout most of the Persian Gulf and surrounding areas, Accumulations of heavy oil and natural asphalts on the Iranian side of the Persian Gulf extend NE to SW along the Qatar arch. some of the geological structures which are located along this trend contain heavy oil and natural asphalts within post- Jurassic formations. The major geologic factor which caused accumulations of heavy oil within some geological structures is the Qatar arch. As a result ,some differences appear in lithologic units in two sub-basins northwest and southeast of the Qatar Arch. In general , the occurrence of heavy oil in this trend can be explained as follows; • Fracturing and joints within formation ; • Reduction of thickness of post- Jurassic sediments; • Facies change of Arab reservoirs, cap rock (Hith anhydrite), in some structures from anhydrite to dolomite and also pinchout; The absence of proper environment for the generation of high gravity oil may also be of importance .It should be mentioned that "F" structure (Ferdows), with huge amount of oil in Ratawi and Sulaiy carbonate reservoirs(Lower Cretaceous), is one of the largest heavy oil fields along this trend .The Farsi "B" structure, ( Farzad), with a thick Jahrum formation (Eocene) which has excellent reservoir properties, is filled with natural asphalts. Manuscript profile
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        48 - Studying Maturity and Migration Routes Using Two-Dimensional Modeling in a number of Dezful Dam Oilfields
        Ashkan Maleki Seyed Ali Moallemi Mohammad Hossein Saberi Mohammad Hassan Jazayeri
        To the southwest of Iran there are large reservoirs of oil and gas including Jurassic and Cretaceous carbonates, with good source rocks in the succession of the Early Cretaceous and Jurassic. The purpose of this study was to investigate the production, migration and cha More
        To the southwest of Iran there are large reservoirs of oil and gas including Jurassic and Cretaceous carbonates, with good source rocks in the succession of the Early Cretaceous and Jurassic. The purpose of this study was to investigate the production, migration and characterization of Pabdeh, Kazhdumi, Garru and Serglu source rocks in the study area. For this purpose, burial history and one-dimensional thermal modeling in four wells and two-dimensional modeling in one section for the study area were evaluated using Openuploo software to determine the maturity of layers and hydrocarbon outflow. Comparison of measured vitrinite temperature and reflectance values with model results was used for model calibration. The results of one-dimensional modelling of the burial and thermal history in this study show that the Sergloo, Grove and Kazhdumi formations have reached maturity and have had hydrocarbon outflow, but the Pabdeh Formation has not reached sufficient maturity for hydrocarbon maturation and production. The results of migration model in the studied section show that the two Early Cretaceous and Middle Cretaceous hydrocarbon systems were separated by Kazhdumi Formation and therefore hydrocarbon migration in deeper layers of Kazhdumi was mostly lateral to Abadan plain. The hydrocarbon produced from the Kazhdumi Formation, in addition to ornithologically rearing the upper layers, migrated to the Ilam and Sarvak layers due to the general slope of the layers laterally and toward the Abadan plain. In general, the process of maturation of source rocks decreased from east to west of the study area. Manuscript profile
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        49 - Biostratigraphy, conodont biofacies and CAI of Late Devonian-Carboniferous deposits in Anarak section, Central Iran
        ٍٍElahe Sattari Ali Bahrami Hosyen Vaziri moghadam Ali Taheri Sandra Isabella  Kaiser Peter Königshof
        Study of Late Devonian-Carboniferous (Mississippian-Pennsylvanian) conodonts Anarak section (NE Isfahan), Central Iran, led to identifying 67 conodont species belonging to 18 genera. 22 conodont bio-intervals were separated; 15 biozones belong to Late Devonian and 7 b More
        Study of Late Devonian-Carboniferous (Mississippian-Pennsylvanian) conodonts Anarak section (NE Isfahan), Central Iran, led to identifying 67 conodont species belonging to 18 genera. 22 conodont bio-intervals were separated; 15 biozones belong to Late Devonian and 7 biozones belong to carboniferous (Mississippian-Pennsylvanian) time interval. Based on field observation and sedimentological featurs and charactristics the section, subdivided into 5 lithostratigrafic unit. The Color Alteration Index (CAI) reveals the hydrocarbure potential for the Famennian stage of the studied interval Manuscript profile
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        50 - 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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        51 - 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
        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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        52 - An attempt to reservoir characterization of Burgan sand, in the northwest of the Persian Gulf toward Kuwait
        Ali reza Bashari
        The Sand tongues of the Albian Kazhdumi Formation is a major prodactive reservoir in North West part of the Persian Gulf towards Kuwait . High porosity and high permeability of these sandstones together with existence of shale either as source rock or cap rock in More
        The Sand tongues of the Albian Kazhdumi Formation is a major prodactive reservoir in North West part of the Persian Gulf towards Kuwait . High porosity and high permeability of these sandstones together with existence of shale either as source rock or cap rock in this formation, have provided all conditions needed for hydrocarbon accumulation. A rapid sea level fall in ealry Albian initiated the deposition of Burgan clastic reservoirs over the Shuaiba Carbonates. The lower Burgan Formation was deposited in a lowstand systems tract represented by massive sandstone reservoirs. High frequency sealevel changes have resulted in deposition of shoreface sands and extensive marine shales within an overall fluvial setting. The middle part Burgan was deposited in a transgressive systems tract. The upper part witnessed a relative sealevel fall in a lowstand systems tract with deposition of sand prone facies in estuarine channels. The clastic cycle was terminated by initiation of Mauddud carbonate sedimentations in transgressive systems tract. A combined effect of allocyclic nesting of sequence stratigraphic packages and autocyclic ramp profile were the primary factors controlling the lithofacies association. This Formation has been informally subdivided into: Lower Interval (C) mainly shaly sands, middle Interval (B) clean sands “main reservoir” and upper Interval (A) interbedded shale & sands. Petrographic analysis shows that the reservoir consists of quartz-rich sands, (typically>70%) and feldspar poor (mainly <5%). Nine authigenetic minerals in the Burgan sands have been identified: quartz, calcite, siderite, pyrite, glauconite along with four groups of the clay minerals. XRD analysis of clay fraction indicates the presence of four clay mineral groups in the Burgan reservoirs : kaolin, illite , chlorite and expandible- lattice mixed –layer, illite/ smectite. Manuscript profile
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        53 - (Biostratigraphy and microfacies of the Asmari Formation in south flank of Mish anticline (northeast of Gachsaran
        Saber Ahmadi Ali seyrafian Hosyen vaziri-Moghadam
        Asmari Formation at the section of the south flank of Mish anticline (northeast of Gachsaran), located 22 km northeast of Basht city, in vicinity village Kalagh ¬Neshin is investigated and has a thickness of 281 meters. In this research, biostratigraphy and microfacies More
        Asmari Formation at the section of the south flank of Mish anticline (northeast of Gachsaran), located 22 km northeast of Basht city, in vicinity village Kalagh ¬Neshin is investigated and has a thickness of 281 meters. In this research, biostratigraphy and microfacies of the Asmari Formation in this section were studied and the results were compared with 5 section of Asmari Formation in similar regions and close to it. By studying on 172 microscopic sections, 3 the biozone for Asmari Formation in the section the study was carried out and the section studied given that is: Lepidocyclina – Operculina – Ditrupa assemblage zone. Archaias asmaricus – Archaias hensoni – Miogypsinoides complanatus assemblage zone. Indeterminate zone. According to the study of benthic foraminifera and biozones, the cut off age is from the late Oligocene (Rupelian-Chattian) to the early Miocene (Aquitanian). Microfacies studies led to identify 10 microfacies and 4 subfacial belonging to the open marine and lagoon (semi-closed and enclosed) environments, which includes the external, intermediate, and interior parts of a hemocalinal ramp. Manuscript profile
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        54 - Qom Formation, Microfacies, Depositional sequence, Maragh area.
        Amrolah Safari Hossein Ghanbarloo Ebrahim  Mohammadi
        The Qom Formation is located at the Maragh area (20 kilometers southwest of Kashan). The formation with 216 m thickness contains shale and limestones. Volcanic rocks unconformably are covered by the Qom Formation. The upper boundary of the Qom Formation with the Upper R More
        The Qom Formation is located at the Maragh area (20 kilometers southwest of Kashan). The formation with 216 m thickness contains shale and limestones. Volcanic rocks unconformably are covered by the Qom Formation. The upper boundary of the Qom Formation with the Upper Red Formation is also unconformable. Nine microfacies and terrigenous facies were identified based on the main components and sedimentological features. These microfacies and terrigenous facies were deposited on an open-shelf carbonate platform. Three environments were recognized in this carbonate platform. These environments include the inner shelf (restricted and semi-restricted lagoon), middle shelf, and outer shelf. In addition, three third-order and one incomplete depositional sequences were identified based on the vertical distribution of microfacies. Manuscript profile
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        55 - Designing an Ensemble model for estimating the permeability of a hydrocarbon reservoir by petrophysical lithology Labeling
        abbas salahshoor Ahmad Gaeini Alireza shahin mossayeb kamari
        Permeability is one of the important characteristics of oil and gas reservoirs that is difficult to predict. In the present solution, experimental and regression models are used to predict permeability, which includes time and high costs associated with laboratory measu More
        Permeability is one of the important characteristics of oil and gas reservoirs that is difficult to predict. In the present solution, experimental and regression models are used to predict permeability, which includes time and high costs associated with laboratory measurements. Recently, machine learning algorithms have been used to predict permeability due to better predictability. In this study, a new ensemble machine learning model for permeability prediction in oil and gas reservoirs is introduced. In this method, the input data are labeled using the lithology information of the logs and divided into a number of categories and each category was modeled by machine learning algorithm. Unlike previous studies that worked independently on models, here we were able to predict the accuracy of such a square mean error by designing a group model using ETR, DTR, GBR algorithms and petrophysical data. Improve dramatically and predict permeability with 99.82% accuracy. The results showed that group models have a great effect on improving the accuracy of permeability prediction compared to individual models and also the separation of samples based on lithology information was a reason to optimize the Trojan estimate compared to previous studies. Manuscript profile
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        56 - 3D modeling of rock types using the integration of core, well logs and seismic data in one of the carbonate reservoirs of southwestern Iran.
        Mahdi Kheirollahi Golnaz  Jozanikohan Reza Mohebian Ali Moradzadeh
        Rock typing is the process of assigning reservoir properties to geological facies, and an identified rock type has similar geological and reservoir properties. Due to the importance of identifying and separating rock types in hydrocarbon reservoirs, various methods have More
        Rock typing is the process of assigning reservoir properties to geological facies, and an identified rock type has similar geological and reservoir properties. Due to the importance of identifying and separating rock types in hydrocarbon reservoirs, various methods have been proposed and developed today for the determination of rock types. One of the simplest methods is the porosity chart against permeability and cut-off determination, and one of the most important and practical of these methods is to determine rock types by flow zone indicator. In this study, we examine one of the most important hydrocarbon fields in the south of Iran where core, well and seismic data are available for the field studied so that by designing a new workflow and with use of the most important and efficient methods of rock typing, including FZI, porosity, Winland-Pitman index, FZI*, and logarithms of FZI and FZI* we have identified rock types in three dimensions and through the whole field. After the final validation, the correlation coefficient values were more than 83%, 57%, 70%, 70%, 73% and 78% for the methods used, indicating greater accuracy and efficiency of the FZI method for the rock types separation in this field. The partial comparison of the validation results after each method employment also confirms the highest accuracy belongs to the FZI method. As a result, by integrating this method with seismic attributes, the rock types have been separated in four different groups throughout the field in three dimensions. Manuscript profile
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        57 - Investigation of petrographical and geochemical characteristics of carbonate deposits of the Jamal Formation in the Chah-Riseh section, northeast of Isfahan
        Behrad  Zebhi Kamand محمد علی  صالحی Ezat  Heydari Ali Bahrami
        The Middle Permian Jamal Formation have been investigated for sedimentological and geochemical aspects in the Chah-Riseh section, northeast Isfahan. According to the field studies the Jamal Formation with 251 m thickness divided into eight lithostratigraphic unit. Lower More
        The Middle Permian Jamal Formation have been investigated for sedimentological and geochemical aspects in the Chah-Riseh section, northeast Isfahan. According to the field studies the Jamal Formation with 251 m thickness divided into eight lithostratigraphic unit. Lower boundary of this formation with an unconformity is underlained by the Sardar Formation which belongs to the Carboniferous period and upper boundary with an unconformity reaches to the Lower Triassic Sorkh-Shale Formation. Facies and microfacies studies of the Jamal Formation led to the identification of two petrofacies and 14 carbonate microfacies. According to the recognized carbonate allochems, petrofacies and microfacies of the Jamal Formation and some evidence such as transitional microfacies changes, we can consider a depositional environment of a shallow mixed siliciclastic-carbonate ramp platform. Petrographically, four types of dolomites are recognized in the Jamal Formation. The dolomitization model for the type I dolomite is considered forming in tidal flat and burial dolomitization for types II, III and IV. Geochemical studies including major and trace elements analysis comprised of elements such as Ca, Mg, Sr, Mn and Fe. Using ratios of the elements and also by plotting some of these elements cross carbon and oxygen isotopes in various diagrams have been used in determining the original mineralogy of carbonate deposits and efficient diagenetic system on the Jamal Formation. The results indicate that the dominant diagenetic environment effected on the carbonate deposits of Jamal Formation was occurred in a semi-closed system and the original mineralogy was aragonite. Evaluation of major and trace elements contents of the four types dolomites, confirmed different characteristics of theses dolomite resembling crystal sizes in petrographic studies. Carbon and oxygen isotopes data of dolomites also defined their diagenetic situations. Manuscript profile
      • Open Access Article

        58 - Examination of climatic orbital changes and sedimentation rate in the Ilam Formation in the Kupal oilfield, Dezful Embayment
        Forough Abasaghi Armin Omidpour
        Carbonate successions are considered archives for recording the palaeoclimatic proxies and so they are suitable for understanding climatic patterns and identifying the Milankovitch cycles and cycles’s impacts on sea-level changes during Phanerozoic. In the current study More
        Carbonate successions are considered archives for recording the palaeoclimatic proxies and so they are suitable for understanding climatic patterns and identifying the Milankovitch cycles and cycles’s impacts on sea-level changes during Phanerozoic. In the current study, the carbonate successions of the Ilam Formation (Santonian) and their spectral gamma-ray data were chosen to identify the cycles and influencing factors on the sedimentation in one of the oilfields in the Dezful Embayment, southwest of Zagros mountains. According to available evidence, all of Milankovitch cycles contributed to changes in climatic conditions simultaneously with development of the Ilam Formation, however, the long Eccentricity cycles were dominant and have played a greater role in this issue. The sedimentation rate was estimated at 4-5.5 cm/kyr on average in the Ilam Formation. Considering the sedimentation rate and number of identified long Eccentricity cycles, it could be said the deposition in the Ilam Formation lasted in 1.13-1.8 Ma. Our results indicate that the relative sea-level changes in the studied wells correspond to the eustatic sea level. The deposition process in the Ilam Formation was largely affected by the performance of long Eccentricity cycles, eustatic sea level, and tectonic events during the Upper Cretaceous. Manuscript profile
      • Open Access Article

        59 - Lithostratigraphy and Biostratigraphy of Pabdeh Formation based on planktonic foraminifera in the Ilam dam section (south Ilam_ Zagros sedimentari basin)
        somaye taherizade Mohammad Vahidinia Mohammadhossein mahmoudi gharaii
        Zagros Sedimentary basin is located in the south and southwest of Iran and Pabdeh Formation is one of the most important Cenozoic units of Zagros Sedimentary basin. In addition, Pabdeh Formation is of special importance as one of the source rocks of Zagros Sedimentary b More
        Zagros Sedimentary basin is located in the south and southwest of Iran and Pabdeh Formation is one of the most important Cenozoic units of Zagros Sedimentary basin. In addition, Pabdeh Formation is of special importance as one of the source rocks of Zagros Sedimentary basin. In order to study the Lithostratigraphic and Biostratigraphic rocks of Pabdeh Formation, the section of Ilam dam in the northwest of Zagros sedimentary basin has been selected and sampled. 360 samples were taken, of which 260 washing samples and 100 thin section samples were prepared. Based on the studies performed on these samples, 25 genera and 105 species have been identified in the Ilam dam section. 26 biozones and 2 sub-biozones have been identified based on the biological zoning of Wade et al., 2011 in the Tethys area. Based on the identified biozones, the age of Pabdeh Formation in the Ilam dam section, Middle Danian-Early Aquitanian has been obtained. The deposits of Pabdeh Formation in the section of Ilam dam have a thickness of 764 m (beginning of Pabdeh to the beginning of Kalhor anhydrite) which includes purple shale units (2 Units), marl limestone with lower limestone, cherti limestone, marl limestone with upper limestone. The lower boundary of Pabdeh Formation in this section is conform and continuous with shales and marls of Gurpi Formation but its upper boundary with the gypsums of the Asmari formation is most likely accompanied by a disconform. Manuscript profile