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 parameters such as porosity, water saturation, hydrocarbon saturation, bulk water volume, etc. were computed and interpreted using Interactive Petrophysics program. Lithological, mineralogical and matrix identification studies were estimated using porosity combination cross plots. Petrophysical properties were determined and plotted as computer processing interpretation (CPI) using Interactive Petrophysics program. Zubair Formation in Luhais oil field is divided into three units according to petrophysical properties: Upper Zubair, Middle Zubair, and Lower Zubair. Middle Zubair is characterized by good porosity but high water saturation. Interpretation of well logs of Zubair Formation founds that Zubair Formation production in well LU-12 is noncommercial but present weak oil shows in some ranges of the formation especially in upper and lower Zubair units but middle Zubair is characterized by free oil shows .Lithological study of Zubair Formation appears that it consists mainly of interbedded sandstone, shale, and shale sandstone whereas mineralogy of Zubair Formation consists mainly of quartz sandstone and Some calcite.
The Hartha Formation is a major carbonate succession deposited during the Late Campanian period. The current study depends on four selected wells (EB 1, 2, 4 and 30) within the East Baghdad oil field to study electrofacies and petrophysical properties related to the reservoir characterization.
The Hartha Formation is divided into three electro-facies units using GR and SP logs in Petrel software. The upper unit of the Hartha Formation is composed mainly of limestone. The middle unit is composing of thick layers of shale. The lower unit is composed mainly of limestone with few shale layers. The three units are divided into three types of rocks in relation to the total porosity: 1. High-moderate active porosity rocks (type I)
... Show MoreThis research is an attempt to solve the ambiguity associated with the stratigraphic setting of the main reservoir (late Cretaceous) of Mishrif Formation in Dujaila oil field. This was achieved by studying a 3D seismic reflection post-stack data for an area of 602.62 Km2 in Maysan Governorate, southeast of Iraq. Seismic analysis of the true amplitude reflections, time maps, and 3D depositional models showed a sufficient seismic evidence that the Mishrif Formation produces oil from a stratigraphic trap of isolated reef carbonate buildups that were grown on the shelf edge of the carbonate platform, located in the area around the productive well Dujaila-1. The low-frequency attribute illustrated tha
... Show MoreRecords of two regionalized variables were processed for each of porosity and permeability of reservoir rocks in Zubair Formation (Zb-109) south Iraq as an indication of the most important reservoir property which is the homogeneity , considering their important results in criterion most needed for primary and enhanced oil reservoir .Z and F tests that were calculated for the two above mentioned properties of pair units of Zubair Formation have shown the difference in depositional energy and different diagenesis between units IL and AB , DJ and AB , and the similarity in grains size , sorting degree , depositional environment and pressure gradients between IL and AB units , LS and IL units ; also the difference in the properties above betw
... Show MoreThe reserve estimation process is continuous during the life of the field due to risk and inaccuracy that are considered an endemic problem thereby must be studied. Furthermore, the truth and properly defined hydrocarbon content can be identified just only at the field depletion. As a result, reserve estimation challenge is a function of time and available data. Reserve estimation can be divided into five types: analogy, volumetric, decline curve analysis, material balance and reservoir simulation, each of them differs from another to the kind of data required. The choice of the suitable and appropriate method relies on reservoir maturity, heterogeneity in the reservoir and data acquisition required. In this research, three types of rese
... Show MoreThe study intends to well logs interpretation to determine the petrophysical parameters of Euphrates Formations in Ajeel Oil Field. The petrophysical properties have been determined from well logging, Euphrates Formation in terms of reservoirs units, consist of two Petrophysical properties. Total porosity, effect porosity and secondary porosity have been calculated from neutron, density, and sonic logs. secondary porosity is high and it's resulted from diagenesis processes in the formation. From RHOB-NPHI and N/M cross plot, Euphrates Formation composed mainly from Limestone and dolomite with nodules of anhydrite. Dhiban Formation composed mainly of anhydrite, so it's represented the cap rocks for Euphrates Reservoir were recognized base
... Show MoreIt is evident from this study that Yamama Formation is reservoir rocks and source rocks at the same time, based on occurrences of crude oil and source rocks. Bulk properties of Yamama oil in six wells as well as comparing several samples of Yamama oil by using the biological mark have indicated multi source of hydrocarbons with some pay having Jurassic and Lower Cretaceouse source affinity that belongs to the Yamama Formation.
The current study summarized the construction of a three-dimensional geological model of the Aquitanian sediments age, which represented by the Euphrates and Serikagni formation in Ajeel Oil Field, where Ajeel Oil Field has structural closure towards northwest - southeast. Sedimentary of the current study consist of limestone, dolomitic limestone, dolomite (compose of skeletal grains, non-skeletal grains and cement) and the appearance of some anhydrite rocks.
The petrographic study of the Euphrates Formation were prepared using a thin section of wells (Aj-1, Aj-4, Aj-5, Aj-6 and Aj-7), Previous studies and geological reports, as well as use well logs data in the statistical analysis by Petrel softwa
... Show MoreThe study of Shiranish Formation rocks in southern part of Iraq at Ansab area well (KH-6)
were carried out. The formation is tongued with tayarat formation, which bounded from top
and bottom, the upper tongue at thickness 49m. and tongued at depth (476-525m.) the lower
tongue at thickness 4m. tongued at (541-537m.).
The rocks of this formation were divided into three sedimentary microfacies:
1- Dolomitized formininferal Wackestone facies.
2- Dolomitized formininferal Mudstone facies.
3- Dolostone facies.
34 slides were investigated depending on mineralogical, compositional and biological
processes and compared diagenesis which reflect open marine shelf at lower part of formation
(F.Z.2) (S.M.F.8), but at the
The detailed data of the Vp/Vs ratio and porosity logs were used to detect the Oil-Water Contact Zone (OWCZ) of Nahr Umr sandstone and Mishrif limestone reservoir formations in Kumiat (Kt) and Dujaila (Du) oil fields, southeastern Iraq. The results of OWC were confirmed using P-wave, Resistivity, and Water Saturation (Sw) logs of Kt-1 and Du-1 wells. It was found that the values of the oil-water contact zone thickness in Nahr Umr sandstone and Mishrif limestone were approximately one meter and eight meters, respectively. These results suggest that the OWCZ is possibly thicker in the carbonate rock than clastic rock formations. The thickness of OWCZ in the clastic rocks changed from one part to another, depending on several factors includ
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