Yamama Formation is an important sequence in southern Iraq. Petrographic analysis was used to determine and analyze the microfacies and pore types. The diagenetic processes and the impacts on the petrophysical properties of the rocks were also identified. The petrographic identification was based on data of 250 thin sections of cutting and core samples from four wells that were supplied by the Iraqi Oil Exploration Company (O.E.C). The present study focuses on the depositional environment and the microfacies analysis of Yamama Formation. The results revealed several types of microfacies, including peloidal wackestone-packstone, algal wackestone-packstone, bioclastic wackestone-packstone, foraminiferal wackestone, bioclastic wackestone, and mudstone. The latter was divided into two submicrofacies, namely argillaceous lime mudstone and sparse fossiliferous lime mudstone. The study showed that Yamama Formation was deposited through various settings within the carbonate platform; these comprise inner ramp, middle ramp, and outer ramp settings. The inner and middle ramp settings, characterized at the top and middle Formation, have high effective porosity and low clay volume, due to dominant packstone.
Rumaila supergiant oilfield, located in Southern Iraq has a huge footprint and is considered as the second largest oilfield in the world. It contains many productive reservoirs, some known but without produced zones, and significant exploration potential. A fault divides the field into two domes to the north and south. Mishrif reservoir is the main producing reservoir in the North Rumaila oilfield. It has been producing for more than 40 years and is under depletion. However, it was subjected to water injection processes in 2015, which assisted in recovery and pressure support. Thus, requirements of managing flooding strategies and water-cut limitations are necessary in the next stages of the field life.
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... Show MoreGlobal oceanic anoxic events (OAEs) are events of immense importance for a variety of reasons. For instance, they are not only behind most if not all of the mass extinctions which took place during the Cenozoic era, but they are the harbinger for the world's best oil source beds, which humanity depends on to satisfy its energy need. In spite of this, there was little effort to document their presence in Iraq, to fill in for the void here, and as a first step, this paper will attempt to establish a cause and effect relationship between OAE 2 and the Gulneri Formation timing of deposition and organic matter richness. This was done by showing the prevalent occurrence of the globally known OAE 2 positive ∂13Corg excursion and the unique ro
... Show More3D seismic reflection structural study of (250) km² of Balad Oil field located in central part of Iraq within Salah Al-din province (Balad area) was carried out.
Faults were picked using instantaneous phase attribute of seismic sections and variance attribute of seismic time slices across 3D seismic volume.
A Listric growth normal fault is affecting the succession of Cretaceous Formation and cut by strike slip fault. In addition, minor normal faults (Dendritic and tension faults) are developed on the listric normal growth fault. As a result, a major graben is separated by Strike slip fault into two parts (north and south parts) and trend in NW-SE direction.
In this research, a qualitative seismic processing and interpretation is made up
through using 3D-seismic reflection data of East-Baghdad oil field in the central part
of Iraq. We used the new technique, this technique is used for the direct hydrocarbons
indicators (DHI) called Amplitude Versus Offset or Angle (AVO or AVA) technique.
For this purposes a cube of 3D seismic data (Pre-stack) was chosen in addition to the
available data of wells Z-2 and Z-24. These data were processed and interpreted by
utilizing the programs of the HRS-9* software where we have studied and analyzed
the AVO within Zubair Formation. Many AVO processing operations were carried
out which include AVO processing (Pre-conditioning for gathe
Characterization of the heterogonous reservoir is complex representation and evaluation of petrophysical properties and application of the relationships between porosity-permeability within the framework of hydraulic flow units is used to estimate permeability in un-cored wells. Techniques of flow unit or hydraulic flow unit (HFU) divided the reservoir into zones laterally and vertically which can be managed and control fluid flow within flow unit and considerably is entirely different with other flow units through reservoir. Each flow unit can be distinguished by applying the relationships of flow zone indicator (FZI) method. Supporting the relationship between porosity and permeability by using flow zone indictor is ca
... Show MoreUpper Cretaceous Oceanic Red Beds (CORBs) are pelagic sediment
deposits that deposited in the Upper Cretaceous basin, with widespread in
part of the world as well as in Iraq. This research investigates the deposition
of cyclic marl and marly limestone CORBs of six selected sections at the
active southern margin of the Tethys during the Late Campanian -
Maastrichtian with petrography, microfacies, and depositional environment.
As this study was not a consideration in the past, so decided to visit and
identify all exposure areas of the Upper Cretaceous period rocks are visited.
This study involved two fields touring reconnaissance extended from
Darbandikhan city in the east south to Shiranish Village in the west
As the reservoir conditions are in continuous changing during its life, well production rateand its performance will change and it needs to re-model according to the current situationsand to keep the production rate as high as possible.Well productivity is affected by changing in reservoir pressure, water cut, tubing size andwellhead pressure. For electrical submersible pump (ESP), it will also affected by numberof stages and operating frequency.In general, the production rate increases when reservoir pressure increases and/or water cutdecreases. Also the flow rate increase when tubing size increases and/or wellhead pressuredecreases. For ESP well, production rate increases when number of stages is increasedand/or pump frequency is
... Show MoreSpatial data analysis is performed in order to remove the skewness, a measure of the asymmetry of the probablitiy distribution. It also improve the normality, a key concept of statistics from the concept of normal distribution “bell shape”, of the properties like improving the normality porosity, permeability and saturation which can be are visualized by using histograms. Three steps of spatial analysis are involved here; exploratory data analysis, variogram analysis and finally distributing the properties by using geostatistical algorithms for the properties. Mishrif Formation (unit MB1) in Nasiriya Oil Field was chosen to analyze and model the data for the first eight wells. The field is an anticline structure with northwest- south
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The heterogeneity nature of carbonate reservoirs shows sever scattering of the data, therefore, one has to be cautious in using the permeability- porosity correlation for calculating permeability unless a good correlation coefficient is available. In addition, a permeability- porosity correlation technique is not enough by itself since simulation studies also require more accurate tools for reservoir description and diagnosis of flow and non-flow units.
Evaluation of reservoir characterization was conducted by this paper for Mishrif Formation in south Iraqi oil field (heterogeneous carbonate reservoir), namely the permeability-porosity correlation, the hydraulic units (HU’s) an
... Show MoreIn this research, a geotechnical assessment was conducted for clay of the Gercus Formation to determine its suitability for embankment dams. The selected area is located in the north of Iraq. Six samples were collected from two sites in Dokan (Sulaimaniyah) and Haibat Sultan mountain (Koysinjaq), three samples each. Various geotechnical (physical, mechanical and chemical) tests were conducted based on standard specifications.
The results of the grain size test of clay samples showed their conformity with Zone C curves and their suitability for the construction of embankment dams, according to the Iraqi standard for roads and bridges. The results of the
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