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

The research dealt with the reservoir division for Upper Shale Member from Zubair formation in Luhais field, Where it was divided into six units of reservoir and non-reservoir, including the main reservoir unit 1C, which is the subject of research in this study, and studied in terms of thickness and lithology.                                                                       

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In this paper, we attempt to predict the depositional environments with associated lithofacies of the main reservoir of the late Cretaceous Mishrif carbonate Formation, depending on the analysis of the created seismic isopach map by integrating seismic and well data. The isopach map was created from a 3D-seismic reflection survey carried out at the Dujaila oil field in southeastern Iraq, which is of an area of 602.26 Km2, and integrated with the data of the two explored wells. Based on the interpretation of the seismic isopach map, the diagram of the 3D-depositional environment model of Mishrif Formation was constructed. It showed three distinguished depositional environments, which were graduated from a back reef lithofacies of a shallo

Permeability is one of the essential petrophysical properties of rocks, reflecting the rock's ability to pass fluids. It is considered the basis for building any model to predict well deliverability. Yamama formation carbonate rocks are distinguished by sedimentary cycles that separate formation into reservoir units and insulating layers, a very complex porous system caused by secondary porosity due to substitute and dissolution processes. Those factors create permeability variables and vary significantly. Three ways used for permeability calculation, the firstly was the classical method, which only related the permeability to the porosity, resulting in a weak relationship. Secondly, the flow zone indicator (FZI) was divided reservoir into

       The lithostratigraphic and biostratigraphic studies of the Shiranish Formation in the Diana area, Erbil, Northern Iraq, were conducted to distinguish the main lithostratigraphic units, depositional environment and the formation age. The Shiranish Formation in the study area can be divided into three rock units. The lower and upper units consist of marly limestone, marl and limestone deposited in the outer shelf environment, while the middle unit is dominated by laminated calcareous shale and marl deposited in the upper bathyal environment. Calcareous nannofossils showed the presence of about 20 species/genera in the studied Shiranish Formation. Three biozones are identified; Misceomarginatus pleniporus biozone;

      The Yamama Formation is characterized by a wide geographic extension of southern Iraq. Microfacies analysis of this formation was studied in six wells distributed in six fields: Fayhaa, Sindbad, Siba, Zubair, Ratawi and West Qurna. This research aims to determine paleoenvironments by diagnosing biofacies and lithofacies. Miscellaneous marine fauna of foraminifera and calcareous algae, mainly green algae (dasycladacean.) and skeletal bioclasts from gastropods, pelecypods, bryozoans, sponge spicules, and echinoderms were found. Petrographic studies and well logs interpretations led to the identification of five main Microfacies ( Mudstone, Wackestone, Packestone, Grainestone and Rudstone and twelve submicrofacies (Foraminiferal-

The major objective of this paper is to recognize the flow units of Yamama Formation in the west Qurna oil field, south of Iraq. To attain this objective, four wells namely, WQ-23, WQ-148, WQ-60, and WQ-203 are selected and analyzed. The two techniques hat proposed by some scientists to identify flow units are tested and verified. Results are also enhanced using well logs interpretation and the flow areas are proposed through the studying of the behavior of different well logs. Results of applying the two proposed techniques identify six flow reservoir units for the wells WQ-23, WQ-148, WQ-60, and WQ-203, respectively. This study also shows that the flow reservoir properties in the Yamama Formation improved towards the northeast of the W

Reservoir rock typing integrates geological, petrophysical, seismic, and reservoir data to identify zones with similar storage and flow capacities. Therefore, three different methods to determine the type of reservoir rocks in the Mushrif Formation of the Amara oil field. The first method represents cluster analysis, a statistical method that classifies data points based on effective porosity, clay volume, and sonic transient time from well logs or core samples. The second method is the electrical rock type, which classifies reservoir rocks based on electrical resistivity. The permeability of rock types varies due to differences in pore geometry, mineral composition, and fluid saturation. Resistivity data are usually obtained from w

Petrophysical properties of Mishrif Formation at the Tuba field determined from interpretation of open log data of(Tu-2,3,4,5,6,12,24,and 25) wells. These properties include total (effected) and secondary porosity, as well as moveable and residual oil saturation into invaded and uninvaded zones. According to Petrophysical properties it is possible to divided Mishrif Formation into three reservoir units (RU1,2,and 3) separated by four cap rocks (Bar1,2,3,and 4) . Three-dimension reservoir model is established by used (Petrel, 2009) Software for each reservoir units. Result shows that the second and third reservoir units represent important reservoir units of Mishrif Formation. Thickness and reservoir properties enhanced toward middle and

The middle Cenomanian – early Turonian Mishrif Formation, a major carbonate reservoir unit in southern Iraq, was studied using cuttings and core samples and wireline logs (gamma‐ray, density and sonic) from 66 wells at 15 oilfields. Depositional facies ranging from deep marine to tidal flat were recorded. Microfacies interpretations together with wireline log interpretations show that the formation is composed of transgressive and regressive hemicycles. The regressive hemicycles are interpreted to indicate the progradation of rudist lithosomes (highstand systems tract deposits) towards distal basinal locations such as the Kumait, Luhais and Abu Amood oilfield areas. Transgressive hemicycles (transgressive systems tract deposits)