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        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
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        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
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        3 - Biostratigraphy and paleoecology of the Asmari Formation at Tang-e Shivi, north-west flank of Nowdan Anticline in north of Kazerun (Interior Fars) and age correlation with three another sections in Costal Fars and Izeh Zone
        ٍٍElahe Sattari
        Abstract In this research, the Asmari Formation΄s benthic foraminifera at Tang-e Shivi north-western flank of Nowdan Anticline in north of Kazerun (Interior Fars), with geographic coordinates E: 51° 44' 58'' and N: 29° 47' 42'', have been studied in order to introduce More
        Abstract In this research, the Asmari Formation΄s benthic foraminifera at Tang-e Shivi north-western flank of Nowdan Anticline in north of Kazerun (Interior Fars), with geographic coordinates E: 51° 44' 58'' and N: 29° 47' 42'', have been studied in order to introduce assemblage zones, age and paleoecology and correlate the age of the Asmari Formation with sections in Costal Fars and Izeh Zone (Firozabad, Dill, Shagabil). Its upper and lower boundaries are comfortable with Gachsaran and Pabdeh formations. Three assemblage zones at the studied section were recognized based on benthic foraminifera and biostratigraphy study. Detected biozones reflect Oligocene (Rupelian and Chattian) and Miocene (Aquitanian) age for this studied deposits with 348 meters thickness. Assemblage zone 1, with Firozabad section and assemblage zone 2 with 3 other sections and assemblage zone 3 with Dill anticline are correlatable. Environmental parameters such as: salinity, light, nutrients, temperature and depth, have played a role concerning the distribution of foraminifera. Accordingly, the Asmari Formation deposited in a normal salinity to hyper salinity water, aphotic to euphotic and oligophy to eutrophy zones. Grain supported microfacies (O4, O5, B, L1, L2, L4, L5 and L7), support reservoir quality for the Asmari Formation in subsurface areas, next to the studies section. The carbonate grain association types of the study section are nanofer, rodalgal, foralgal and foramol. Manuscript profile
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        4 - 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
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        5 - 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

        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
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        7 - Reservoir zonation using discrimination of effective and ineffective porosity method in one of the SW Iranian oil Fields; a special look at resistivity logs
        جواد هنرمند ژیلا رضائیان دلوئی ارسلان زینل زاده
        Abstract In this paper, core samples from Upper carbonates (Miocene age) of the Asmari Formation in one of the SW Iranian oil fields were studied in macro and microscopic scale. Subsequently, results from core and thin section studies compared with core porosity and pe More
        Abstract In this paper, core samples from Upper carbonates (Miocene age) of the Asmari Formation in one of the SW Iranian oil fields were studied in macro and microscopic scale. Subsequently, results from core and thin section studies compared with core porosity and permeability and petrophysical wireline logs, especially resistivity logs. Due to texture variation (mudstone to grainstone) and diagenetic events (dolomitization, dissolution, calcite and anhydrite cementation), porosity type and percentage changed in wide range in this formation. This study showed that resistivity logs could be used as an effective tool to distinct effective and ineffective-bearing zones. High permeability intervals have relatively high deep resistivity and high separation between deep and shallow resistivity logs, whereas non-reservoir intervals have low resistivity and very low separation between deep and shallow resistivity. Based on this study, studied carbonate interval of the Asmari Formation was divided into 13 zones. Using separation of deep and shallow resistivity logs, flow zones could be correlated throughout the studied field Manuscript profile
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        8 - Oligocene microfacies and sedimentary environment of the Asmari Formation at northwest of Deris village, west of Fars province: correlation with three other sections in Zagros Basin
        samir Akhzari Ali Seyrafian
        In this disquisition, Oligocene (Rupelian-Chattian) microfacies and sedimentary environment of the Asmari Formation at the northwest of Deris village, located in interior Fars zone of the Zagros Basin have been interpreted. The coordinates of such section are N: 29o 4 More
        In this disquisition, Oligocene (Rupelian-Chattian) microfacies and sedimentary environment of the Asmari Formation at the northwest of Deris village, located in interior Fars zone of the Zagros Basin have been interpreted. The coordinates of such section are N: 29o 41' 59'', E: 51 o 32' 26''. The Asmari Formation deposits in this section are divided into 5 lithological units and consist of 460 m thin, medium, thick and massive bedded, gray and cream to gray limestone, slightly dolomitic with nodular and marly interbedded. By study of hyaline benthic foraminifera genera and non-foraminifera, and also recognition of some properties such as skeletal ingredient associations and sedimentary textures of thin sections, 14 microfacies have been introduced for the Asmari Formation. Gradual perpendicular changes of these microfacies represent that settling the Asmari Formation deposits took place in a homoclinal rapm. This homoclinal ramp consists of middle ramp and inner ramp, that are separated by shoal environment. Middle ramp is recognized by presence and dominition hyaline benthic foraminifera, coralline red algae and echinoids. The most significant skeletal debris of inner ramp are porcelainous foraminifera. To compare the thickness, age and sedimentary environment, zonal correlation of the Asmari Formation done in Deris section with three other sections (Naura anticline, Dill anticline and Dehloran) in the Zagros Basin. This correlation represent that the age of the Asmari Formation gets younger to the deeper parts of the foreland basin of the Zagros. Manuscript profile
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        9 - Microfacies and depositional environment of the Asmari Formation in the Izeh zone
        Mohammad.reza Taheri Ali asghar Gabishavi
        In this study, microfacies features of the Asmari Formation have been studied. The study area is located in the Izeh zone, in the vicinity of Izeh city. Accordingly four outcrop sections (Halayjan, Kuh Shur, Kuh-e Bad and Gharibi Ha) have been sampled and investigated. More
        In this study, microfacies features of the Asmari Formation have been studied. The study area is located in the Izeh zone, in the vicinity of Izeh city. Accordingly four outcrop sections (Halayjan, Kuh Shur, Kuh-e Bad and Gharibi Ha) have been sampled and investigated. Due to unique tectonical characteristic and lateral as well as spatial variations of the outcrops, different facies have been deposited across the Asmari Formation platform in the study area. Based on the sedimentary structures, texture, skeletal and non-skeletal grains, 11 microfacies have been recognized which have been deposited in three different sub environments including open marine, shoal and lagoon. Based on this reaserch, for the Asmari Formation, three independent depositional models have been considered during the Chattian, Aquitanian and Burdigalian. On the basis of the results of this study, during the Chattian, Aquitanian and Burdigalian the Asmari Formation has been deposited in a homoclinal ramp system. During the Burdigalian toward the NE of study area (Gharibi Ha section), the shallow water deposits are abruptly overlain by pelagic limestone. Therefore, during the Burdigalian toward the NE of study area, probably, the carbonate ramp has been changed to drowned carbonate platform. It is interpreted as the result of a regional tilting that started in the late of the Burdigalian. During the Chattian in the Gharibi Ha area, the base of the carbonate Asmari Formation transits into the marl-dominated Pabdeh Formation towards the Halayjan area which could be concerned as an analogue to investigate about the stratigraphic oil traps potential in the Izeh zone. Manuscript profile
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        10 - 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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        11 - Biostratigraphy, microfacies and sedimentary environment of the Asmari Formation at Somghan area and correlation with other sections in the Zagros basin
        Mehrnaz Rahimzadeh Ali Seyrafian Ali Rahmani
        The difference in the depositional setting of the Zagros, causes multiple carbonate facies.The Asmari Formation deposited in the foreland basin during Oligo-Miocene time. In this study, biostratiography and microfacies of the Asmari Formation at Nowdan anticline next to More
        The difference in the depositional setting of the Zagros, causes multiple carbonate facies.The Asmari Formation deposited in the foreland basin during Oligo-Miocene time. In this study, biostratiography and microfacies of the Asmari Formation at Nowdan anticline next to Somghan village (39 Km north of Kazerun) are studied. The thickness of the Asmari Formation is 302 meters and its upper and lower boundries are coverd. Field work studies resulted to recognize 4 lithostratigraphic units (unit 1: thin to medium bedded limestone, unit 2: thick and some thin and medium bedded limestone, unit 3: thin and thick bedded nudular limestone, unit 4: thin bedded nudular limestone). Based on microscopic studies, 20 genera and 19 species of benthic foraminifera were identified and two biozones related to the Oligocene were identified. Based on textural and faunal studies, nine microfacies related lagoon and open marine were differentiated. Also in this study, to reconstract geometry and to analyze the role of Qatar-Kazerun fault during Oligocene, 11 sections of the Asmari Formation were examined. Manuscript profile
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        12 - 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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        13 - 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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        14 - Biostratigraphy and microfacies analysis of the Shahbazan and Asmari formations (through Eocene to Oligocene) in the carbonate deposits of northwest Dezful Embayment, Zagros Sedimentary Basin
        sepedeh Gholampoor-moghahi Hosyen Vaziri moghadam Naser Arzani Afshin Armoon
        Abstract In this research based on petrography study of 320 thin sections (cutting samples), biostratigraphy, microfacies and depositional environment analysis has been done to determine the boundary between the Shahbazan and Asmari formations in well No. 1 of the Bala More
        Abstract In this research based on petrography study of 320 thin sections (cutting samples), biostratigraphy, microfacies and depositional environment analysis has been done to determine the boundary between the Shahbazan and Asmari formations in well No. 1 of the Balarud Oil Field, located in the north of Dezful embayment. The Shahbazan Formation with 460 meters thick with mainly composed of dolomite along with interlayers of limestone, shale and anhydrite in the studied well. The lower boundary of this formation with the Pabdeh Formation is conformable and its upper boundary with the Asmari Formation is marked by an unconformity. The Asmari Formation with thickness of 140 meters mainly consists of limestone and shale with the interlayers of dolomite; its upper boundary to the Gachsaran Formation is conformable. Biostratigraphy studies documented a high diversity of shallow-water benthic and rare planktonic foraminiferas and led to the determining of one assemblage zone in the Shahbazan Formation (15 genera and 8 species) that indicates age of the Priabonain. Three assemblage zones also were recognized in the Asmari Formation (12 genera and 8 species) that, shows the age of the Asmari Formation from Mid-Rupelian to the Chattian, Aquitanian and Burdigalin. Based on biostratigraphy studies, the boundary between Shahbazan and Asmari formations and the position of an unconformity between them were determined. The facies analysis led to recognition of eight microfacies for the Shahbazan Formation which belong to three facies belts of inner (tidal flat and lagoon), middle and outer ramp, deposited on a ramp-type carbonate platform. Also four microfacies were recognized in the Asmari Formation which are related to the inner carbonate platform. Manuscript profile
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        15 - 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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        16 - The impact of microfacies and diagenesis characteristics on the reservoir quality of Asmari Formation in the Gevarzin gas field, Zagros basin, south Iran
        Karim  Mombani   Ahmad Yahyaei
        Asmari Formation from the Gavarzin gas field have erosional unconformity boundary on marl and pelagic limestones of Pabdeh Formation and gradually change to evaporate cap rock of Gachsaran Formation. Cores studies from the one of wells of Gavarzin field is 183 m in thic More
        Asmari Formation from the Gavarzin gas field have erosional unconformity boundary on marl and pelagic limestones of Pabdeh Formation and gradually change to evaporate cap rock of Gachsaran Formation. Cores studies from the one of wells of Gavarzin field is 183 m in thickness, which includes 1.30 m from the top of Pabdeh, 162.4 m from the Asmari Formation and 19.30 m from the base layers of Gachsaran. Asmari Formation includes alternation of limestone, calcite dolomitic, claystone and shale with green marl. Petrology and facies analysis of the sequence of these formations identified 12 microfacies, a carbonate ramp from deep-sea to sabkha environments and formed in a retrograded sequence. This ramp includes deep environments, open sea, patch reef, bio-, clastic-bars, lagoon and tidal environments, which confirms a changing environment due to rapid facies changes and deposition of evaporative sediments in Gachsaran as a restricted environment. Diagenesis processes are considered as the main factors in carbonate reservoir quality of Gavarzin field. The diagenesis history of the Asmari carbonates of the studied cores is summarized as A) marine phreatic diagenesis, bioturbation, micritization and cementation processes occurred. B) vadose zone diagenesis, where the crystallization, cementation, and dissolution occurred. C) burial diagenesis, comprises compression-induced, pressure dissolution and fracturing are common. The microfacies show a wide varieties of reservoir characteristics and therefore a heterogeneous reservoir has been formed. Micro-fractures, however have strongly influence on the reservoir quality in the section. The simultaneous presence of dissolved spaces and fractures in the reservoir the permeability greatly increased. The best reservoir quality in the Grainstone/Packston facies are coated grains with moldic porosity that were created by the leaching of Ooid-bearing Packston lithology during the diagenesis of atmospheric waters. Manuscript profile
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        17 - (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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        18 - Isotopic and Geochemical comparison of Bangestan and Asmari Oils to determine origination
        ashkan Zardashti Morteza Tabaei mahmood memariani
        In order to analyze the geochemical characteristics, the oil samples of the Asmari reservoirs and the Bangistan group in the Kopal field were studied using various geochemical techniques such as asphalting technique, gas chromatography technique, gas chromatography-mass More
        In order to analyze the geochemical characteristics, the oil samples of the Asmari reservoirs and the Bangistan group in the Kopal field were studied using various geochemical techniques such as asphalting technique, gas chromatography technique, gas chromatography-mass spectrometry technique and carbon isotope measurement technique, were subjected to analysis. the purpose of This research is a comparison of carbon isotope and geochemical properties of Asmara and Bangestan oils in Kopal field to determine their parent rock and origin. Considering the results of the testing technique and analysis of biomakers of the esteranes and terpanes family extracted from saturated cutting, it can be stated that the oils accumulated in the Asmari and Bangestan reservoirs of the Kopal field have the characteristics of oil. are paraffinic, which indicates the existence of light oil with good quality, mature, low viscosity and high sulfur. By placing the ratio of biomarker parameters against carbon 13 isotope and examining the general results of the graphs, it was found that the oil samples of Asmari reservoirs and Bangestan reservoirs in the studied field are from a common generative rock. have been found and have the same characteristics and only slightly differ in maturity, degree of fluidity, and the amount of migration processes between the source rock and the reservoir rock, and similarly, the transformation course of the source rock organic materials has occurred naturally in the Copal field. The values of carbon isotopes in the oils indicate the average maturity of the rocks producing the oils. The graph of the ratio of the aromatic carbon 13 isotope against the saturated carbon 13 isotope showed that both field oil samples The subject of study belongs to marine environments. Manuscript profile
      • Open Access Article

        19 - Reconstruction of Asmari Formation Sedimentary Environment in Asmari and Gurpi Anticlines in the oil field of Masjed Soleiman (Southwest of Iran)
        Navab Varnaseri Davood Jahani Nader Kohansal Ghadimvand Mohsen Pourkermani
        In this research, the process of lithological changes and diagenetic processes of Asmari formation with Oligo-Miocene age has been investigated. For this purpose, 400 samples were selected and collected from a section of the Masjid Suleiman oil field and the surface sec More
        In this research, the process of lithological changes and diagenetic processes of Asmari formation with Oligo-Miocene age has been investigated. For this purpose, 400 samples were selected and collected from a section of the Masjid Suleiman oil field and the surface section of the Asmari anticline in the Dezful depression and the Gurpi anticline in the Izeh zone. Petrographic studies revealed 18 sedimentary microfacies that were deposited on a ramp-type carbonate platform. Among the significant diagenetic processes in the region are the process of micritization, bioturbation and the influence of burrowing organisms, cementation (types of cement related to marine, meteoric and burial diagenesis environments), dissolution (meteoric and burial dissolution), dolomitization (in different phases), silicification, pyritization, phosphatization, mechanical compaction, chemical compaction, fracture and porosity. Based on the identification of the sequence boundaries and following the facies depth changes, the carbonate sequence of the Asmari formation in the subsurface section and the Asmari anticline section are introduced in the form of 3 sedimentary sequences of the third order shallowing upwards, which are the former Aquitanian, the late Aquitanian and Bordigalin belong. Among the dominant porosities in the Asmari Formation, we can mention the hole, mold and fracture porosities. Manuscript profile
      • Open Access Article

        20 - Stratigraphy, facies and depositional conditions of the Asmari Formation (Rupelian-Burdigalian) in the south-eastern folded Zagros, Bandarlengeh embayment (Khamir salt mountain section)
        Peyman Rezaei Seyedeh Akram  Jooybari Abdullah  Najafi
        Asmari Formation (Rupelian-Burdigalian) is one of the most well-known formations in Iran. In order to investigate the stratigraphy and sedimentary environment, a section of this formation was selected in Khamir salt mountain section in Bandarlengeh embayment. In this nu More
        Asmari Formation (Rupelian-Burdigalian) is one of the most well-known formations in Iran. In order to investigate the stratigraphy and sedimentary environment, a section of this formation was selected in Khamir salt mountain section in Bandarlengeh embayment. In this number, 70 limestone microscopic thin sections and 3 marl samples (XRF) were evaluated to identify the microfacies and the sedimentation conditions.The petrographic study led to the identification of 10 microfacies belonging to the facies belts of tidal, lagoon, carbonate bar, open marine, which were deposited in the homoclinal carbonate ramp environment. The composition of marl facies oxides also indicates the presence of carbonate minerals, quartz and clay minerals, which along with field observations and alternating calcareous facies suggest that this facies was deposited in an open marine environment. Finally, it seems that the facies and fossil diversity of the Asmari Formation in the mentioned section is such that during the Aquitanian stage, this formation was located closer to the coast line and during the Rupelian and Chattian-Burdigalian times, it was located at a further distance from the coast line. Manuscript profile