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    • List of Articles paleoecology

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        1 - 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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        2 - 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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        3 - 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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        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
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        6 - Foramniferal morphogroups of the Qom Formation in E Sirjan and SW Kashan: implication for paleoenvironmental and paleoecological interpretations
        Ebrahim  Mohammadi
        The Qom Formation is the main reservoir and source rock of hydrocarbons in central Iran. Foraminifera are now central to our ability to date, correlate and analyse the sedimentary basins that are currently key to the economic wellbeing of the world. Morphogroup analysis More
        The Qom Formation is the main reservoir and source rock of hydrocarbons in central Iran. Foraminifera are now central to our ability to date, correlate and analyse the sedimentary basins that are currently key to the economic wellbeing of the world. Morphogroup analysis, due to independence of species level taxonomy, as wel as permit to comparison of assemblages of differing ages, is a useful tool for ecological and palaeoecological interpretation. It is independent of species level taxonomy and is thus relatively elementary to translate from one worker to another. Foramniferal study of the Qom Formation in the Bujan (eastern Sirjan; with Rupelin-Chattian in age and 156 m thickness) and Varkan (southwestern Kashan; with Rupelin in age and 190 m thickness) sections resulted in identification of seven morphogroups. The morphogroups were distinguished according to test/shell morphology and architecture (general shape, mode of coiling, and arrangement and number of chambers), inferred life habitat either living on the surface of the sediments or within the sediments (epifaunal and infaunal), and feeding strategy (suspension-feeder, herbivore, etc.). Generaly, epifaunal morphogroups were dominated in both study sections. The morphogroup analyses showed variations in the percentage of the dominant morphotypes, suggesting fluctuations in the paleoecological conditions. In the Bujan section, the Rupelin deposits are dominated by calcareous porcelaneous morphogroups; while the Chattian deposits are dominated by hyaline morphogroups, which indicates the lower and upper parts were deposited in inner ramp (lagoonal environments) and middle ramps, respectively. This significant change through time reffers to gradual increasing of the basin depth, decreasing the light intensity, reducing the salinity and decreacing the nutrient level. De dominance of the hyaline morphogroups throughout of the Varkan section is indicative of the deposition in middle ramp environments with normal salinity under meso-photic to oligo-photic conditions. Manuscript profile
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        7 - Biostratigraphy and paleoecology of Family Gavelinellidae in Sanganeh and Aitamir Formations at the Kopeh-Dagh basin
        Maryam Motamedalshariati Mahmoud Jalali
        The sedimentary basin of Kopeh-Dagh is located in the northeast of Iran. This sedimentary basin has been of interest for a long time because of hydrocarbon materials. Gavelinellids are the most abundant and dominant groups of benthic foraminifera in epicontinenal seas d More
        The sedimentary basin of Kopeh-Dagh is located in the northeast of Iran. This sedimentary basin has been of interest for a long time because of hydrocarbon materials. Gavelinellids are the most abundant and dominant groups of benthic foraminifera in epicontinenal seas during Cretaceous period which belong to Rotaliinacean foraminifera. They have shown a wide biogeographical distribution and dispersion in many areas of Tethys. Their evolutionary trend during the Cretaceous time was success. The high concentration of marine sedimentary rocks and the absence of igneous activities in the Kope-Dagh sedimentary basinhave caused it to be considered the most suitable basin for the formation and accumulation of hydrocarbons after the Zagros sedimentary basin. This basin has suitable layers of carbonate rocks and porous sandstones to store hydrocarbon materials, also thick layers of shales in this basin can act as suitable source and cap rocks. In this research some genera and species from this family in Sanganeh and Aitamir Formations at five stratigraphic sections including Marave Tappeh, Takal kuh, Sheykh, Gadvecanlou and Kalat from point of biostratigraphical and paleoecological applications have been investigated. In this study, four biozones including Gavelinella flandrini-Gaudryina cf. praedividens assemblage zone, Berthelina intermedia assemblage zone, Berthelina cenomanica Assemblage Zone, Berthelina intermedia-Osangularia schloenbachi Assemblage Zone have been introduced. Based on the reported genera and species of the Gavellinidae family, it can be stated that the studied formations were deposited in the middle and outer part of the continental shelf to the upper part of the continental slope and in aerobic to semi-aerobic environments. The presence of more planktonic foraminifera than benthic foraminifera in the Aitamir Formation, the depth of the basin increases. Manuscript profile