An interpretive (structural and stratigraphic) study of the two,-dimensional seismic, data of East Nasiriya area (30 km to the south east of Nasiriya oil field within Thi-Qar province, southeastern Iraq) was carried out using Petrel 2017 program. The study area has an importance due to its location between many oil fields, but still without exploration of oil wells. Twenty five seismic lines were used, date back to different types of seismic surveys conducted in the region at different time periods. Also, the seismic velocity surveys of the nearest wells to oil fields, such as Nasiriya-1 and Subba-8, in addition to their sonic and density logs were used. A synthetic seismogram with a good matching with the seismic section was achieved to ensure the identification of the reflectors and reflectivity type (peak or trough) and follow up each one through the whole area of interest. Top Zubair reflector was picked using the composite line to link the seismic sections with each other after enhancing the ties between seismic lines. Time and depth maps were made using velocity maps created from the velocity model. The seismic, interpretation, in the area showed the existence of certain stratigraphic, features, in the ,studied reflector. Some distribution mounds and sand lenses were observed in the study area, which are continuous in more than two-dimensional seismic line in the area. These activity elements provide a reasonable explanation for the distribution of hydrocarbons in the area of study.
This study deals with seismic structural and stratigraphic interpretation that applied on the East Razzaza (central of Iraq) area, by using 2D seismic data from Oil Exploration Company. Three main seismic reflectors are picked. These reflectors are Zubair, Yamama and Gotnia Formations, which were defined by using petrophysical well logs and synthetic traces that calculated from sonic- logs of the wells East Baghdad-1(Eb-1) and West kifl-1(Wk-1) using Geoframe program, to suggest a stratigraphic model for them. Structural maps of formations are prepared to obtain the location and direction of the sedimentary basin and shoreline. Seismic interpretation of the area approves the presence of some stratigraphic features in the studied formatio
... Show MoreZubair oilfield is an efficient contributor to the total Iraqi produced hydrocarbon. Drilling vertical wells as well as deviated and horizontal wells have been experiencing intractable challenges. Investigation of well data showed that the wellbore instability issues were the major challenges to drill in Zubair oilfield. These experienced borehole instability problems are attributed to the increase in the nonproductive time (NPT). This study can assist in managing an investment-drilling plan with less nonproductive time and more efficient well designing.
To achieve the study objectives, a one dimension geomechanical model (1D MEM) was constructed based on open hole log measurements, including Gamma-
... Show MoreThe lower Cretaceous sandstones of Zubair and Nahr Umr formations are the main producing reservoirs in Subba oilfield in southern Iraq. Key differences in their petrophysical and depositional attributes exist affecting their reservoir characteristics. The evaluation of well logs and core porosity-permeability data show better reservoir properties in Nahr Formation. The Litho-saturation logs indicate greater thickness of oil-saturated reservoir units for Nahr Unr Formation associated with lower values of shale volume, and higher values of effective porosity. In addition, higher values of permeability for Nahr Umr Formation is suggested by applying porosity-irreducible water saturation cross plot. The reducing reservoir quality of Zub
... Show MoreKnowing the distribution of the mechanical rock properties and the far field stresses for the field of interest is an important task for many applications concerning reservoir geomechanics, including wellbore instability analysis, hydraulic fracturing, sand production, reservoir compaction, and subsidence. A major challenge with determining the rock's mechanical properties is that they cannot be directly measured at the borehole. Furthermore, the recovered carbonate core samples for performing measurements are limited and they provide discrete data for specific depths.
The purpose of this study is to build 2D and 3D geomechanical models of the Khasib reservoir in the East Baghdad oil field/ Central area. TECHLOG.2015.3 softwa
... 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 MoreMultiple eliminations (de-multiple) are one of seismic processing steps to remove their effects and delineate the correct primary refractors. Using normal move out to flatten primaries is the way to eliminate multiples through transforming these data to frequency-wavenumber domain. The flatten primaries are aligned with zero axis of the frequency-wavenumber domain and any other reflection types (multiples and random noise) are distributed elsewhere. Dip-filter is applied to pass the aligned data and reject others will separate primaries from multiple after transforming the data back from frequency-wavenumber domain to time-distance domain. For that, a suggested name for this technique as normal move out- frequency-wavenumber domain
... Show MoreThis research represents a reflection seismic study (structural and stratigraphic) for a (852) km2 area located in the south of Iraq within the administrative border of the province of Al-Muthanna and Qadisiyah province ,by using 2-D seismic data from Oil Exploration company three main seismic reflectors are picked, these are (Zubair and Yamama) Formations which they deposited during the Cretaceous age , and (Gotnia) Formation which deposited during Jurassic age .Structural maps of Formations are prepared to obtain the location and direction of the sedimentary basin and shoreline ,time, velocity and depth maps are drawn depending on the structural interpretation of the picked reflectors and show several structural feature as nose structu
... Show MoreThe study deals with 3D seismic reflection in the central Iraq within Merjan oil field which is located approximately (130 km) to the southwest Baghdad and south of Razaza. The 3D seismic survey was interpreted; the results showed that the oil is found within Hartha Formation as stratigraphic traps and with the absence of structural traps. The major normal faults picked are trending N-S direction. There are also minor faults observed using the instantaneous phase and frequency sections, they proved the presence of the faults and showed that the ending of the Safawi reflector toward the north and northeast to the south and southeast and near the western border of fault because of the facies change in the area. The reflector shows a struct
... Show MoreTwenty-five groundwater samples from the Al-Zubair area, southern Iraq, were analyzed for physical and chemical variables. The study showed that the groundwater is of acidic type and in it tends towards light alkalinity. Both electrical conductivity and the total dissolved solids showed increased concentrations of sodium, calcium, magnesium, potassium and sulfate, chloride, bicarbonate, and nitrate. The hydrochemical formula for most groundwater wells are (Ca-Cl), (Ca-SO4), (Mg-SO4), and (Na-Cl) type due to the high concentrations of these ions in the water., it was found that this water is not suitable for human drinking. Due to its high salinity compared to the requirements of international standard and Iraqi standa
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