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    • List of Articles دالان

      • Open Access Article

        1 - Study of Petrography & Petrophysics of Permian- Triassic carbonate sediments in Qatar –South Pars Arch
        Ali reza Bashari
        Abstract Dalan and Kangan Formations are major gas reservoirs in the Persian Gulf and surrounding area. Several supper giant gas fields has been found in the region. In this study reservoir rock types were identified and were divided into four lithostratigraphic zo More
        Abstract Dalan and Kangan Formations are major gas reservoirs in the Persian Gulf and surrounding area. Several supper giant gas fields has been found in the region. In this study reservoir rock types were identified and were divided into four lithostratigraphic zones: K1 to K4. Each of the four succeeding zones have been divided into different subzone. This Studies identified different facies-types on the Dalan and Kangan formation in this region. Petrophysical & Petrographycal studies indicate that the best reservoir unites are found in: Dolo-grainstones, Dolowakestones/Packstones and Grainstones. Isopach maps and Depth maps show variations in thickness and depth of different zones in this region. Depth map on top of Kangan formation shows this formation getting deeper toward north- west and south east in the Persian Gulf. Continuity of marker beds in Permian/Triassic sediment and paleontological evidence support diachroneity of these sediments. Manuscript profile
      • Open Access Article

        2 - Dalan and Lower Kangan units in Persian Gulf with special emphasis on the Permo/ Triassic boundary
        سعیده منیبی نواب خدائی زیبا  زمانی پژوه
        Abstract The Upper Dalan and Lower Kangan stratigraphic units with 225m thickness were studied in one of the subsurface section in Persian Gulf area. According to the biostrarigraphic investigation on the dolomitic and limestone successions of the Upper Dalan unit, th More
        Abstract The Upper Dalan and Lower Kangan stratigraphic units with 225m thickness were studied in one of the subsurface section in Persian Gulf area. According to the biostrarigraphic investigation on the dolomitic and limestone successions of the Upper Dalan unit, there are more than 30 index foraminifera and non-foraminifera species. One Paradagmarita/ Paraglobivalvulina/ Baisalina Assemblage Zone that divided to three distinct sub- assemblage zones 1. Rectostipulina quadrata/ Globivalvulina vonderschimitti Assemblage subzone 2. Dagmarita chanackchiensis/ Ichtyolaria latilimbata Assemblage subzone 3. Hemigordiopsis renzi/ Paradagmarita flabeliformis Assemblage subzone have been distinguished in the stratigraphic section representing the Julfian to Earleast Dorashamian stage. The identified microfauna' assemblages can be corresponded to the Late Permian regional biozonation in the Tethys realm. The latest microfauna assemblages in the latest part of Dalan Formation exhibits a significant chronostratigraphic hiatus, just was cited in the Dalan/ Kangan (Permo/Triassic) boundary. There is no any evidence about Latest Dorashamian sediments in the study area. The Permo/Triassic boundary is a paraconformity type in the latest Permian biozones, which can be corresponded to other areas of the world. The Lower Kangan stratigraphic unit can be attributed to the Schytian age (Early Triassic age) on basis of presence of some index fossils such as Bivalves (Claraia sp.) and Serpulids (Spirorbis sp.). It should be stressed that the similar microfauna associations can be seen in other Iranian places such as Central Iran and Alborz areas, which is documented a distinct palaeobiogeographical relationship between the above-mentioned areas and Zagros realm on Permian and Triassic ages. Manuscript profile
      • Open Access Article

        3 - 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