This paper includes studying the microfacies evalution of Mauddud Formaion in
four wells(Rt-2, Rt-5, Rt17 and Rt-19). Seventy-seven(77) sampels were collected
of above mentioned wells. Based on fossil content of the samples under study, four
main microfacies were identified: packstone , wakestone , grainstone and lime
mudstone microfacies ,which deposited in shallow open marine and restricted
marine environments. Petrographic examination of thin section indicated that
diagenesis vary in intensity from one site to another, such as dissolution,
cementation, compaction, dolomitization and micritization, which led to the
improvement and deterioration of porosity. The dominant pore types are vuggy,
interparticle and intercrystal.The lithology, mineralogy and the matrix were
determined by using crossplot method, which showed that the predominant
lithology of the formation is limestone with the presence of dolomite in very few
percentages and the mineralogy is calcite. Based on the relationship between
porosity and permeability the resevoir performance of the microfacies classified
into four types: bad, fair, good and very good. Based on petrophysical properties
and core description of well study Mauddud Formation was divided into four rock
units A,B,C and D , in terms of reservoir, units A and C are considered good ,while
B and D are bad.
Diagenetic processes and types of pores that control the reservoir properties are studied for Mauddud Formation in selected wells of Badra oil field, central Iraq. The microscopic study of the thin sections shows the effects of micritization, cementation, neomorphism, dissolution, dolomitization, compaction, and fracturing on Mauddud Formation carbonate microfacies. The decrease of porosity is resulted from cementation, compaction, and neomorphism. Different types of calcite cement occlude pore spaces such as drusy cement, syntaxial rim cement, and granular (blocky) cement. The neomorphism of micritic matrix and skeletal grains reduces porosity as indicated by development of microspar or pseudospar. Evidence of decreasing porosity by com
... Show MoreThe Hartha Formation is one of the important formations deposited during Late Campanian age.
The present study deals with four boreholes (EB-53, 54, 55 and 56) within the East Baghdad oil field to diagnoses the microfacies and interpret the depositional environments.
Six major microfacies were recognized in the succession of the Hartha Formation. Their characteristic grain types and depositional texture enabled the recognition of paleoenvironment. There are Orbitoides wackestone-packstone , Orbitoides - miliolid wackestone, Peloidal and Pellets - echinoderm wackestone to packstone, Peloidal wackestone to packstone, Pelletal wackestone to packstone, and Planktonic foraminifera wackestone-packstone.
Four assoc
... Show MoreSix main microfacies are identified which are Lime Mudstone, Bioclastic Wackeston, Bioclastic Packstone-Wackestone, Bioclastic Wackestone- Mudestone, Pelagic Mudstone–Wackestone, Bioclastic Packstone -Grainston Microfacies in addition to their associated depositional environment. The diagenesis process have affected the Mishrif rocks and played a role in deteriorating reservoir porosity in well Ga-2 and enhancing it in well Ga1,3.These processes include: cementation, micritization, recrystallization,dissolution,compaction pressure solution and dolomitization.
The Ratawi Oil Field (ROF) is one of Iraq's most important oil fields because of its significant economic oil reserves. The major oil reserves of ROF are in the Mishrif Formation. The main objective of this paper is to assess the petrophysical properties, lithology identification, and hydrocarbon potential of the Mishrif Formation using interpreting data from five open-hole logs of wells RT-2, RT-4, RT-5, RT-6, and RT-42. Understanding reservoir properties allows for a more accurate assessment of recoverable oil reserves. The rock type (limestone) and permeability variations help tailor oil extraction methods, extraction methods and improving recovery techniques. The petrophysical properties were calculated using Interactive Petroph
... Show MoreGas Chromatography GC, Gas Chromatography–Mass spectrometry GC/MS techniques used for analysis of the crude oils that taken from (10) producing wells in Nasiriyah oil field including (NS-1, NS-3, NS-4, NS-5, NS-6, NS-7, NS-8, NS-9, NS-10, and NS-12) from Mishrif reservoir . This reservoir is one of the important reservoirs in Al-Nasiriyah oil field, and it will be the main subject in the current study in order to provide information of crude oil analysis in this area, also to provide information on its characterizations. Mishrif Formation is one of the principle carbonate reservoir in central and southern Iraq. It is part of the wasia group and widespread throughout the Arabian gulf, It is deposited during Cenomanian-Early Turonian cyc
... Show MoreThe Mauddud Formation was one of the important and widespread Lower Cretaceous period formations in Iraq. It has been studied in three wells (EB. 55, EB. 58, and EB. 59) within the East Baghdad Oil Field, Baghdad, central Iraq. 280 thin sections were studied by microscope to determine fauna, the formation composed of limestone and dolomitized limestone in some parts which tends to be marl in some parts, forty species and genus of benthic foraminifera have been identified beside algae and other fossils, three biozones have been identified in the range which is: Orbitolina qatarica range zone (Late Albian), Orbitolina sefini range zone (Late Albian – Early Cenomanian) and Orbitolina concava range zone (Early Cenomanian), The age of
... Show MoreThe aim of this study is to investigate the feasibility of underground storage of gas in Um El-Radhuma formation /Ratawi field. This formation is an aquifer consisting of a high permeable dolomitebeds overlain by impermeable anhydrite bed of Rus formation. Interactive petrophysics (IP), Petrel REand Eclipse 100 softwares were used to conduct a well log interpretation, build a reservoir simulationmodel and predict the reservoir behavior during storage respectively. A black oil, three dimensionaland two phase fluid model has been used. The results showed that the upper part of Um El-Radhumaformation is suitable for underground gas storage, because of the seal of its cap rock and capability ofreserving gas in the reservoir. It was foun
... Show MoreIn the region of the north of Iraq using the method of analyzing thin section microfacies to 38 of rockyslices which were gathered from a place near Aqra city. These slides are divided into seven microfacies depending on lithologcal component and fossils.
1) Dolostone facies.
2)Recrystallized bioclastic wackestone facies.
3) Bioclastic packstone microfacies
4)Sucrosic dolomite facies.
5) Bioclastic grainstone in microfacies.
According to water energy, these facies were divided to three zone:
- a) Low energy environment.
- b) Transitional zone.
- c) High energy environment.
Ratawi Field is a promising hydrocarbon bearing structure conforming several reservoirs, and lies northwest of the Basrah city and west of Northern Rumaila Field. Kinetic Analysis referred to that the type of Fold of Ratawi Structure similar to the types which are associated with Salt Structure activity.Geophysical Interpretation referred to the presence of Salt Structure beneath Ratawi Structure. The Isopach Maps shows that the crest thickness is less than the limbs, this characteristics is always due to those of salt structures beneath Ratawi field. Both of Tectonic Movement and Salt Structure play a great role in forming and development of Ratawi Structure.
A 2D geological model for Mauddud Formation in the Badra oil field is built using Rockworks 16 software. Mauddud Formation produces oil from limestone units; it represents the main reservoir in the Badra oil field. Six wells (BD-1, BD-2, BD-4, BD-5, P-15, and P-19) are selected to build facies and petrophysical (Porosity and Water saturation) models. Wells data are taken from the core and cutting samples and studied through the microscopic. The petrophysical data (effective porosity and water saturation) are derived from computer processes interpretation results that are calculated by using Interactive Petrophysics software. The 2D models are built to illustrate the vertical and horizontal distribution of petrophysical properties between we
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