Hydrocarbon migration in the Zagros Basin, offshore Iran, for understanding the fluid flow in the Oligocene-Miocene carbonate reservoirs

Kuh-e Mond Field is a conventional heavy oil resource in the Zagros foreland Basin, Iran, produced from the fractured carbonates partially filled by dolomite, calcite, and anhydrite cement. Vitrinite reflectance data from carbonate reservoir suggest low-maturation levels corresponding to paleotemperatures as low as 50 °C. The observed maturation level (<0.5% R(max)) does not exceed values for simple burial maturation based on the estimated burial history. Oil inclusions within fracture-filled calcite and dolomite cement indicate the key role of these fractures in oil migration. The fluid inclusion temperature profiles constructed from the available data revealed the occurrence of petroleum in dolomite, calcite, and anhydrite and characterize the distinct variations in the homogenization temperatures (T(h)). Fluid inclusions in syntectonic calcite veins homogenize between 22 °C and 90 °C, showing a salinity decrease from 22 to 18 eq. wt.% NaCl. Fluid inclusions in anhydrite homogenize at <50 °C, showing that the pore fluids became warmer and more saline during burial. The T(h) range in the calcite-dolomite cement depicts a change in water composition; therefore, we infer these cements precipitated from petroleum-derived fluids. The microthermometry data on the petroleum fluid inclusions suggest that the reservoir was filled with heavy black oils and high-salinity waters and indicate that undersaturated oil was present in a hydrostatically pressured reservoir. The T(h) data do not support vertical migration of hot fluids througout the section, but extensive lateral fluid migration, most likely, drove tectonically dewatering in the south or west of the pool.Z. Shariatinia, M. Haghighi, S. Feiznia, A.H. Alizai, G. Levress

Halite fluid inclusion geochemistry of evaporite deposits in central Iran.

The chemical analyses of major ions in primary halite fluid inclusions is widely used for the determination and characterization of brine chemistry and its evolution in ancient evaporite basins through the Phanerozoic (eg. Ayora et al., 2001; Brennan and Lowenstein, 2002; Horita et al., 2002; Kovalevich et al., 2002). The purpose of this study is to show the major ion compositional evolution and halite crystallization pathway in the Miocene, M1 member of the Upper Red Fm. (N, Great Kavir Basin, Iran). We show how the Rift setting of the Great Kavir Basin, exerted the main control on the modification of seawater major ion chemistry. Influx of Ca-Cl2 brines modified the earlier evaporated seawater into Ca- Mg- Na- Cl brines. In this case, the Ca2+ concentration of the evolving brine exceeded overall concentrations of SO42-, HCO3-, and CO32- ions, which is expressed as mCa2+>Σ(mSO42- + mHCO3- + mCO32-). From this modified brine MgSO4-poor potash salts (mainly halite, sylvite and carnallite) precipitated. The study of major ion variation for evaporite deposits in the mentioned area reveals that the evaporation path in the Great Kavir Basin was not the same as present-day seawater. The geochemical diagrams (e.g. Mg vs. SO4 and K) show that major ions followed different evolution trends. Seemingly, an externally Ca-Cl2 influx would have overridden the chemical signature of evaporated seawater within Great Kavir Basin. As a result, sylvite instead of K-Mg-sulfates precipitated, similar to that observed in other rift settings such as the Danakil Depression (Ethiopia) in Quaternary evaporates where secular seawater compositional changes can not justified the observed lithologies. Ayora C., Cendn D. I., Taberner C., and Pueyo J. J. (2001) Brine-mineral reactions in evaporite basins: Implications for the composition of ancient oceans. Geology 29(3), 251-254. Brennan S. T. and Lowenstein T. K. (2002) The major-ion composition of Silurian seawater. Geochimica et Cosmochimica Acta 66(15), 2683-2700. Horita J., Zimmermann H., and Holland H. D. (2002) Chemical evolution of seawater during the Phanerozoic: Impliations from the record of marine evaporites. Geochimica et Cosmochimica Acta 66(21), 3733-3756. Kovalevich V. M., Peryt T. M., Beer W., Geluk M., and Halas S. (2002) Geochemistry of Early Triassic seawater as indicated by study of Rt halite in the Netherlands, Germany and Poland. Chemical Geology 182, 549-563.International Union of Geodesy and Geophysics (IUGG); International Association of Seismology and Physics of the Earth's Interior (IASPEI

Paleofluid analysis from fracture-fill cements in the Asmari limestones of the Kuh-I-Mond field, SW Zagros, Iran

Kuh-I-Mond field in the Zagros foreland basin is a conventional heavy oil resource and is composed of fractured carbonates whose fractures were filled by calcite, dolomite, and anhydrite cements. Oil inclusions occurred within the fracture-fill cements indicate that fractures were open and played an active role during oil migration and charge. The highest measured values for secondary porosities belong to fractures in Asmari Formation, which is characterized by significant amounts of vug- and fracture-filling cements. Fractures facilitated fluid circulation and subsequently dissolution of allochems and high Mg carbonates. In contrast, fine-grained carbonate facies were less cemented, and thus, porosity enhancement by cement dissolution was insignificant. Temperature profiles of oil inclusions in the dolomite, calcite, and anhydrite minerals characterized by distinct variations in the homogenization temperatures (Th) that are divided into two ranges below 50°C in anhydrites and from 45°C to 125°C in dolomites and calcites. The lower Th ranges for anhydrite suggests that it may have formed at shallower burial depths during early to middle diagenesis. The oil inclusions display trend for increasing temperature downward which conform to Formation geothermal gradient. In other word, the decreasing trend of Th temperatures upward within Asmari Formation that can be observed in Th versus depth plot is consistent with the uplift events at Late Miocene time and later that caused removal of about 1,300 m of the crest of the Kuh-I-Mond anticline. Vitrinite reflectance data from source rock intervals in the field area do not support vertical migration of locally generated hydrocarbons into the Kuh-I-Mond accumulation, and long-distance lateral oil migration and charge from a source kitchen to the southwest is proposed. Vitrinite reflectance data from this dolomite and limestone reservoir suggest low maturation levels corresponding to paleotemperatures less than 50°C. The observed maturation level (<0.5% Ro) does not exceed values for simple burial maturation based on the estimated burial history. Also, homogenization temperatures from fluid inclusion populations in calcite and dolomites show expected good correlation with reflectance-derived temperatures. The Th data represent pore fluids became warmer and more saline during burial. As aqueous fluid inclusions in calcite veins were homogenized between 22°C and 90°C with a decrease in salinity from 22 to 18 eq. wt.% NaCl. The Th values suggest a change in water composition and that dolomite and calcite cements might have precipitated from petroleum-derived fluids. The hydrocarbon fluid inclusions microthermometry data suggest that the reservoir was being filled by heavy black oils in reservoir during Cenozoic. Aqueous fluid inclusions hosted by calcite equant sparry/fossil cavity fills suggest low cementation temperatures (<45°C) and high salinities (19 eq. wt.% NaCl), while those in dolostones are characterized by highly variable homogenization temperature (52°C to 125°C) and salinities (6.5 to 20 eq. wt.% NaCl).Zeinab Shariatinia, Manouchehr Haghighi, Sadat Feiznia, Don Hall, Gilles Levresse, Ali Mousavi Dehghani and Masoud Rashid

Applying petroleum inclusions micro-thermometry in reconstructing the oil types in Asmari-Jahrum formation Iran

Conference details: 3rd Biennial Conference on Asian Current Research on Fluid Inclusions ACROFI - III and 14th International Conference on Thermobarogeochemistry TBG - XIV, held 15-20 September, 2010, Novosibirsk, Russia.Shariatinia Z., Levresse G., Parnell J., Haghighi M., Feiznia S., Moallemi S.A., Dehghani Mousavi S.A.http://acrofi.igm.nsc.ru

In vitro antibacterial property assessment of silver nanoparticles synthesized by Falcaria vulgaris aqueous extract against MDR bacteria

Silver nanoparticles (AgNPs) were fabricated in the presence of Falcaria vulgaris aqueous extract as a biosynthesis method without utilizing any surfactant or template. AgNPs were prepared under different synthesis conditions such as silver ion concentration and the amount of plant used for the extraction, reaction duration and temperature for the extraction. The effect of these variables on the size of resulted AgNPs was examined, and operation conditions were optimized statistically with analysis of variance (ANOVA) to describe the role of these variables in tuning the size of AgNPs. The results of ANOVA displayed the optimum conditions for the synthesis procedure that resulted in AgNPs with the average size of 28 ± 8 nm. Furthermore, the growth of AgNPs was monitored by UV-Vis spectroscopy, and they were characterized using TEM, SEM, X-ray diffraction, and FT-IR spectroscopy. Finally, in vitro antibacterial activity of the AgNPs showed the maximum inhibition zone alongside Staphylococcus aureus (ATCC 25923) and lowermost inhibition zone touching E. coli (MDR). The minimum inhibitory concentration (MIC) for the AgNP-Fv was in a range between 0.535 and 0.001 µg/ml. According to the results, the ATCC bacteria were more sensitive to AgNP-Fv compared to multiple-drug resistance bacteria, except for Pseudomonas aeruginosa (MDR). Figure not available: see fulltext.. © 2019, Springer Science+Business Media, LLC, part of Springer Nature