The Albian Carbonate-clastic succession in the present study is represented by the Mauddud and Nahr Umr formations were deposited during the Albian stage within the Wasia Group More than 200 thin sections of cores and cuttings in addition to well logs data for Nahr Umr and Mauddud formations from 4 boreholes within two oil fields (Ba-4, Ba-8, Ns-2 and Ns-4) were used to interpret the different associations facies as well as the facies architectures to describe the sedimentary framework of the basin and development the petrophysical properties. Seven major microfacies were diagnosed in the carbonate succession of the Mauddud Formation, while the Nar Umr Formation includes five lithofacies; their grain types characteristic and depositional textures enabled to recognize of paleoenvironments. These microfacies were deposited in restricted, shallow open marine, back-reef, slope and deep open marine for the Mauddud succession. While in Nahr Umr, the lithofacies were deposited in bay fill, back-shore and distributary channel. The studied succession in Balad oil field which represents two 3rd order and four 4th order cycles (A1, A2, A3 and A4). These cycles are asymmetrical and starts with cycle A1 where the Backshore facies in Lower Mauddud Formation represents the transgressive systems tract and then appear the hightstand systems tract bounded below by a transgressive surface which coinside with the unconformable surface with the underlying Shuaiba Formation. In Nasyria oil field the studied succession represents two 3rd order cycles and three 3rd order cycles (A1, A2 and A4) with absence of A3 cycle. These cycles are asymmetrical and starts with cycle A1 where the distributary channel in the lower part of Nahr Umr succession represents the transgressive systems tract bounded below by unconformable surface with the underlying Shuaiba Formation. The highstand systems tract of cycle A1 is reflected by shallowing upward for distributary channel, bay fill and back-sore facies of the Nahr Umr Formation. This relatively thick parasequence reflect time of sea level stillstand where tectonic subsidence is the major controlling factor on producing the necessary accommodation for thick aggregational to progradation clastic succession to deposit.
3D geological model for each reservoir unit comprising the Yamama Formation revealed to that the formation is composed of alternating reservoirs and barriers. In Subba and Luhais fields the formation began with barrier YB-1 and four more barriers (YB-2, YB-3, YB-4, YB-5), separated five reservoirs (YR-A, YR-B, YR-C, YR-D, YR-E) ranging in thickness from 70 to 80 m for each of them deposited by five sedimentary cycles. In the Ratawi field the formation was divided into three reservoir units (YR-A, YR-B, and YR-C) separated by two barrier units (YB-2 and YB-3), the first cycle is missing in Ratawi field.
The study involves 1 well in Luhais field (Lu-12), 3 wells in Subba field (Su-7, Su-8, and Su-9), and 5 wells in Ratawi fi
... Show MoreThe thermal maturity , burial history and petroleum generation history of four oil wells selected from four oil fields in Southern Iraq, they are: Nasiriyah(Ns-1 well) , Gharraf (GA-5well) ,Abu Ammood (Ab-1well) and Riffai (Ri-1well) have been studied using 1D basin and petroleum systems modeling. Results showed different period of subsidence, which ranges from high to moderate subsidence, occurred at upper Jurassic to Mid-Cretaceous and slow subsidence in Miocene . The porosity in the studied area represents the highest value in Dammam , Tayarat ,Um-Eradhuma and Khasib Formations. For most of the studied wells, the Paleocene to Miocene has to be regarded as times when the maximum temperature prevailed assoc
... Show MoreThe Turonian-Lower Companian succession at Majnoon Oil Field is represented by the Khasib, Tanuma, and Saadi formations. Four major paleoenvironments were recognized within the studied succession, there are: Shallow open marine environment, shoal environment, deep marine environment, and basinal environment. They reflect deposition on a carbonate platform of homoclinal ramp setting. The studied succession represents two second order supersequences (A) and (B). Supersequence (A) includes both the Khasib and Tanuma formations. The Saadi Formation represents cycle (B). These second order cycles can be divided each into two third order cycles, This subdivision may reflect the effect of eustacy being the major controlling factor of cycles dev
... Show MoreThis research had been achieved using 2D seismic sections to study the presence of subsurface salty bodies in the Khashim Al-Ahmer, Galabat, Injana fields as a case study. The selected oil fields is located to the northeast of Baquba city within Diyala Governorate.
The study aims to determine the salt accumulations of the selected fields and their role in the formation of oil traps.
The interpretation of seismic data was focused on two reflectors Fatha and Jeribe Formations which belong to the lower and Middle Miocene. Structurally, Two systems of reversal faults are affecting the fields, according to seismic sections, the first represents thrust faults affected on the top part of Fatha (Red Beds &
... Show MoreThis research includes the study of the harsh environment areas in which engineers and workers operate in drilling oil wells, and their own characteristics in terms of nature and the climate and other surrounding factors, that negatively large amount affect on all the staff, present in comparison with other lands, so the study showed the preparations administrative and methodology that must be taken to confront the problems that may arise or for the purpose of avoiding. One of these things should be addressed is the process of adaptation of the staff live in the remote desert land and under difficult living conditions. The study also demonstrated all kinds of diseases and ill health which afflict the staff due to climatic conditions that
... Show MoreReservoir fluids properties are very important in reservoir engineering computations such as material balance calculations, well testing analyses, reserve estimates, and numerical reservoir simulations. Isothermal oil compressibility is required in fluid flow problems, extension of fluid properties from values at the bubble point pressure to higher pressures of interest and in material balance calculations (Ramey, Spivey, and McCain). Isothermal oil compressibility is a measure of the fractional change in volume as pressure is changed at constant temperature (McCain). The most accurate method for determining the Isothermal oil compressibility is a laboratory PVT analysis; however, the evaluation of exploratory wells often require an esti
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