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    • List of Articles Ali reza Bashari

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        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
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        2 - Al Khalij field in Qatar, and extension toward Reshadat Oil Field, in the Persian Gulf
        Ali reza Bashari
        Alkhalij field located offshore Qatar , was discovered in 1991 and put into production in 1997. The field is original in many aspects. it is one of the few carbonate reservoir with stratigraphic closure, the oil is being trapped in upper part of a monocline due to a l More
        Alkhalij field located offshore Qatar , was discovered in 1991 and put into production in 1997. The field is original in many aspects. it is one of the few carbonate reservoir with stratigraphic closure, the oil is being trapped in upper part of a monocline due to a lateral variation in reservoir facies. In addition, the reservoir lies within the capillary transition zone and consists of a succession of highly conductive oil bearing layers ( drains) in between matrix layers of poor permeability. High- resolution 3D seismic has revealed additional area developed, which were previously considered to be uneconomic. Resent 4D seimic pilot has given encouraging result to utilize Seismic Technologies to analyse the evolution of the Al Khalij oilfield over time. Studies shows, this field possibly extended toward Reshdat oil field. Manuscript profile
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        3 - Facies, thickness variations and reservoir characterisation of Arab formation (Surmeh) in the Eastern part of the Persian Gulf
        Ali reza Bashari
        The Kimmerigian-Tithonian) Arab Zone are the prolific hydrocarbon bearing resrvoirs in the eastern part of the Persian Gulf,offshore,Iran.They were deposited in an arid climate which dominate during late Jurassic. The Berriasian to Thitonian Hith formation wich o More
        The Kimmerigian-Tithonian) Arab Zone are the prolific hydrocarbon bearing resrvoirs in the eastern part of the Persian Gulf,offshore,Iran.They were deposited in an arid climate which dominate during late Jurassic. The Berriasian to Thitonian Hith formation wich overlies the Arab reservoir constitutes the cap rock,wich just to the east gradually pinches out and form a N-S feather adge. The study reveals that Arab zones form a massive to interbedded anhydrite with varying proportion of limestone and dolomite and generally have regressive units which was deposited on a broad carbonate platform .This formations are thick in center (Salman field) and mostly consist of intertidal pack/grainstones with high porosity/permeability,good cap rock and also close to the source rock,which has the most hydrocarbon potential, but towards east the layers getting thinner with unsuitable cap rock and are away from source rock ,so as a result Arab formation in this part of the Persian Gulf doesn,t seem to be attractive. This study reveals that there is still some undrilled structure within this area which could be attractive for further Exploration drilling. Manuscript profile
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        4 - Impact of shale oil revolution on falling of Oil and Gas prices Technical report
        Ali reza Bashari
        The rapid development of shale gas resources in the US has transformed the world gas-market outlook. Despite this, the consensus was for a long time that shale gas would not be a ‘game changer’ in the world as it has been in the US. Shale gas is extracted from solid roc More
        The rapid development of shale gas resources in the US has transformed the world gas-market outlook. Despite this, the consensus was for a long time that shale gas would not be a ‘game changer’ in the world as it has been in the US. Shale gas is extracted from solid rock using a process called hydraulic fracturing, or ‘fracking’. Static shows, in USA, production rates decline, for the most of well on average, 80 0r 85 percent over the three years. In order to maintain current level of shale gas production, Hughes estimates that the high rates of deterioration of such wells across the US will require the drilling of 7,000 new wells a year at cost of $42 billion annually. For the maintenance of overall production of shale oil, some 6,000 new wells would need to be drilled every year, an endeavor that would cost $ 35 billion. A number of environmental concerns have been raised about fracking, including the potential for seismic events, air pollution, surface and groundwater contamination, and greenhouse gas emissions. There is no doubt that shale revolution has been a game-changer in short term, but the implication shows that it is not sustainable in long-term. Manuscript profile
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        5 - 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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        6 - 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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        7 - Hydrodynamic activity in the Mishrif reservoirs: an approach to characterize Sarvak formation , in eastern part of the Persian Gulf
        Ali reza Bashari
        The hydrodynamic activity and its effects on oil water contact of oil fields in Sirri district ( Eastern Part of the Persian Gulf), has been revealed by drilling and coring of third well of Mishrif reservoir, (SiDA1) on 1976. Discovery of Sirri –D1 ( Dena) i More
        The hydrodynamic activity and its effects on oil water contact of oil fields in Sirri district ( Eastern Part of the Persian Gulf), has been revealed by drilling and coring of third well of Mishrif reservoir, (SiDA1) on 1976. Discovery of Sirri –D1 ( Dena) in 1972 and SiD-2 confirm existence of oil only 5 meter at the top of structure. Field development started in 1975 and showed the existence of tilted, oil- water contact along fairly south –north direction with slopes up to 12:1000, particulary on the western flank of structure. Slope and direction of water level of Sirri-C ( Sivand) which is close to Sirri-D (Dena) , contain the same slope in both field, at the eastern border of field. The oil –water contact of Sirr- E, (Alvand) field has been constructed with good accuracy and fair probability in 1978. As a result, this modeling was confirm with actual result after full field development of this field on 2002. An entirely original study has been undertaken on residual oil of core, which permitted to characterize various zone as well as modern and fossil interfaces, and proved Hydrodynamic activity in the Mishrif reservoir in western part of Persian Gulf ( Sirri District). This study was carried out, with an approach to combined reservoir characterization , and revealed accuracy of results after full development of these fields. Manuscript profile
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        8 - Integration of petrophysical and Seismic data: an Attempt to Geological model, Ilam reservoir oil field, Sirri District , in the Persian Gulf.
        Alireza Bashari
        Ilam Formation is deposited at the late Cretaceous (Santonian) in a neritic/pelagic environment. Following the Ilam deposition, a general deepening has occurred and the Gurpi formation (shaly layer) was deposited. Ilam has thickness variation between 75-110m and st More
        Ilam Formation is deposited at the late Cretaceous (Santonian) in a neritic/pelagic environment. Following the Ilam deposition, a general deepening has occurred and the Gurpi formation (shaly layer) was deposited. Ilam has thickness variation between 75-110m and structure has created as a result of upward movement of deep seated salt. Ilam reservoir in this field is regarded as a secondary hydrocarbon potential, and since now, no oil has been produced from this horizon. petrophysical and Seismic interpretation has been done for the Ilam reservoir, the geological models (structural and property models) are generated, with both deterministic and stochastic approaches. The seismic attributes as secondary variables, improved the kriging and Sequential Gaussian Simulation (SGS) algorithm results for modeling of Ilam. This study reveals that Water Saturation is generally high, indicating that Ilam reservoir has low hydrocarbon potential, within the five reservoir potential zones, the zone 5 indicated a good original oil in place potential, especially in the western and central parts of the field. Manuscript profile
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        9 - Petrophysical Modeling of Lower Zone of Ratawi Formation, using Neural Network Method in Assimilating Seismic and Geological Well Log Data
        Javid Hanachi Alireza Bashari
        Esfandiar field is located at the northern part of the Persian . This field is a single large anticline with Lulu field of Saudi Arabia, with , 20 KM length and 7 KM width. The field was discovered in 1966 by drilling of well E1, on the northern culmination of t More
        Esfandiar field is located at the northern part of the Persian . This field is a single large anticline with Lulu field of Saudi Arabia, with , 20 KM length and 7 KM width. The field was discovered in 1966 by drilling of well E1, on the northern culmination of the field. wells E3 and E2 were drilled at the top of structure in the southern part of the field. DSTs tests results of E1 proved that the top of Lower Ratawi formation contain 15 m oil column. E3 well test result regards as a dry hole DSTs test results of E2 were not conclusive due to inadequate testing plans . E4 Appraisal well contained, 14 m oil column at the Lower Ratawi. Log interpretations results indicated, E2 and E3 wells contains oil in Yamama formation in the southern part of the field which has not been tested properly. Lower Ratawi (Top oil-bearing zone ), Zone 'B' of Lower Ratawi (Oil bearing zone at bottom), Yamama were constructed based on the existing data. Petrophysical and geophysical data has been used for the Lower Ratawi reservoir, as a result the geological models (structural and porosity models), with applying, related software’s and neural network geophysical method are generated . At the conclusion, the recommended plan consists of horizontal drilling wells for oil production in Lower Ratawi in the north of the field has been proposed. Manuscript profile
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        10 - Petrographical factor and Petrophysical parameter: An approach to reservoir evaluation of the Sarvak formation in NW, of the Persian Gulf
        Alireza Bashari
        Sarvak formation is a major oil reservoir in the Persian Gulf. Various nomenclature of the Sarvak formation were applied by different operative oil companies In the northern part of the Persian Gulf. The aim at this study is to harmonize stratigraphical nomenclatu More
        Sarvak formation is a major oil reservoir in the Persian Gulf. Various nomenclature of the Sarvak formation were applied by different operative oil companies In the northern part of the Persian Gulf. The aim at this study is to harmonize stratigraphical nomenclature in this district , as well as to study the reservoir qualities and to asses hydrocarbon accumulations in this area. By using different petrophysical data and integration with geological factor, resulted in revealing three stratigraphy members ( Mishrif, Ahmadi and Mauddud), as well as reservoir qualities variations , in this district. By applying, available petrophsical data, and integration with geological information, various 3D geological maps, ( porosity, water & oil saturation maps etc…) were made. Preliminary assessment of the reservoir potential of the Bahregansar & Hendijan Fields shows , Sarvak formation in these two fields, have a good reservoir qualities, but other part of this district has poor reservoir qualities. This study shows , having high portions of clay mineral in the Sarvak reservoir along with lack of suitable cap rock and poor reservoir qualities , diminished reservoir potentials in this district. Manuscript profile