The Mishrif Formation is one of the most important formation in oil fields, which is located in southern part of Iraq, and it is of Upper Cretaceous age. Tuba field is located nearly 40 km SW – Basrah city. It is bounded from east by Zubair oil field (5 km distance) and from west by Rumaila (2 km distance). The Tuba oil field is situated between Zubair oil field in the east and Rumaila in the west, and is separated by two depressions.
The rock (core and chips) samples have been collected systematically from cores of Mishrif Formation that are available from stores of southern oil company to prepare thin sections and slides—these slides have been examined by using microscope. These samples have been taken from all parts of the reservoir units of Mishrif, namely, mA, mB1, mB2 units. Twenty-four samples have been applied to the petrophysical tests to measure the porosity and permeability. The water and oil saturations have been identified by consulting the log documents for studied wells (7 wells). Besides, four hundred ten rockslides have been made for identifying the facies and diagenices processes.
Four main facies have been diagnosed at Mishrif Formation (Grainstone, packstone, wackstone and mudstone) which are spread all over the reservoir units. Moreover, the diagentic processes have been identified by using microscope to check the rockslides, which have greatly framed the petrophysical characteristics for Mishrif Formation. These processes include dissolution, all categories of porosity, compaction, cementation, new morphisim and dolomitization.
The results of the reservoir geological model show that Tuba field is an anticline fold which its extension is in (north – northwest), (south- southeast) direction. The results have proved that facies model distribution completely match the facies description in the study. This model contains Grainstone, Packstone, Wackstone and Mudstone.
The characterizations of reservoir require reliable knowledge of certain fundamental reservoir properties. Log measurements can define or at least infer these properties: resistivity, porosity, shale volume, lithology, and water, oil, or gas saturation and permeability. The current study represents evaluation of petrophysical properties in well LU-12 for Zubair Formation in Luhais Oil Field, southern Iraq. The petrophysical evaluation was based on geophysical well logs data to delineate the reservoir characteristics of Zubair Formation. The available geophysical well logs such as (sonic, density, neutron, gamma ray, SP, and resistivity logs) are digitized using the Didger software. The environmental corrections and petrophysical paramete
... Show MoreVisualization of subsurface geology is mainly considered as the framework of the required structure to provide distribution of petrophysical properties. The geological model helps to understand the behavior of the fluid flow in the porous media that is affected by heterogeneity of the reservoir and helps in calculating the initial oil in place as well as selecting accurate new well location. In this study, a geological model is built for Qaiyarah field, tertiary reservoir, relying on well data from 48 wells, including the location of wells, formation tops and contour map. The structural model is constructed for the tertiary reservoir, which is an asymmetrical anticline consisting of two domes separated by a saddle. It is found that
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Setting-up a 3D geological model both from field and subsurface data is a typical task in geological studies involving natural resource evaluation and hazard assessment. In this study a 3D geological model for Mishrif Formation in Garraf oil field has been set-up using Petrel software. Mishrif Formation represents the most important reservoir in Garraf oil field. Four vertical oil wells (GA-4, GA-A1P, GA-3 and GA-5) and one directional well (GA-B8P) were selected in Garraf Oil Field in order to set-up structural and petrophysical (porosity and water saturation) models represented by a 3D static geological model in three dimensions. Structural model shows that Garraf oil field represents a domal structure that shows continuous growth as i
... Show MoreSadi formation is one of the main productive formations in some of Iraqi oil fields. This formation is characterized by its low permeability values leading to low production rates that could be obtained by the natural flow.
Thus, Sadi formation in Halfaya oil field has been selected to study the success of both of "Acid fracturing" and "Hydraulic fracturing" treatments to increase the production rate in this reservoir.
In acid fracturing, four different scenarios have been selected to verify the effect of the injected fluid acid type, concentration and their effect on the damage severity along the entire reservoir.
The reservoir damage severity has been taken as "Shallow–Medium– Sever
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This research includes structure interpretation of the Yamama Formation (Lower Cretaceous) and the Naokelekan Formation (Jurassic) using 2D seismic reflection data of the Tuba oil field region, Basrah, southern Iraq. The two reflectors (Yamama and Naokelekan) were defined and picked as peak and tough depending on the 2D seismic reflection interpretation process, based on the synthetic seismogram and well log data. In order to obtain structural settings, these horizons were followed over all the regions. Two-way travel-time maps, depth maps, and velocity maps have been produced for top Yamama and top Naokelekan formations. The study concluded that certain longitudinal enclosures reflect anticlines in the east and west of the study ar
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History matching is a significant stage in reservoir modeling for evaluating past reservoir performance and predicting future behavior. This paper is primarily focused on the calibration of the dynamic reservoir model for the Meshrif formation, which is the main reservoir in the Garraf oilfield. A full-field reservoir model with 110 producing wells is constructed using a comprehensive dataset that includes geological, pressure-volume-temperature (PVT), and rock property information. The resulting 3D geologic model provides detailed information on water saturation, permeability, porosity, and net thickness to gross thickness for each grid cell, and forms the basis for constructing the dynamic reservoir model. The dynamic reservoir mo
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This study aims to set up a 3D static model to characterize and evaluate Mishrif Formation which represents the main reservoir in Buzurgan Oilfield, southern Iraq. Six wells have been selected to set up structural, facies and petrophysical models of Mishrif reservoir by using Petrel Software. The structural model has been built based on the structural contour map of the top of Mishrif Formation, which derived from seismic interpretation, and by using different static algorithms in Petrel Software. The structural model showed that the Buzurgan Oilfield represents an anticlinal fold with two domes north and south separated by a depression. The petrophysical model included the porosity model and water saturation model. Th
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This study aims to determine the petrophysical characteristics of the three wells in the Kifl Oilfield, central Iraq. The well logs were used to characterize hydrocarbon reservoirs to assess the hydrocarbon prospectivity, designate hydrocarbon and water-bearing zones, and determine the Nahr Umr Formation's petrophysical parameters. The Nahr Umr reservoir mainly consists of sandstone at the bottom and has an upper shale zone containing a small proportion of oil. The geophysical logs data from three oil wells include gamma-ray, resistivity, neutron, density, acoustic, and spontaneous potential logs. A gamma-ray log was employed for lithology differentiation, and a resistivity log was used to determine the response of distinct zones
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The objective of this paper is determining the petrophysical properties of the Mauddud Formation (Albian-Early Turonian) in Ratawi Oil Field depending on the well logs data by using interactive petrophysical software IP (V4.5). We evaluated parameters of available logs that control the reservoir properties of the formation, including shale volume, effective porosity, and water saturation. Mauddud Formation is divided into five units, which are distinguished by various reservoir characteristics. These units are A, B, C, D, and E. Through analyzing results of the computer processed interpretation (CPI) of available wells, we observed that the main reservoir units are B and D, being distinguished by elevated values of eff
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