Three seismic instantaneous attributes (phase, frequency, and variance) were utilized on 3D-seismic poststack migrated data, covering 617.31 km2, integrated with data of two wells (Du-1 and Du-2) in Dujaila oil field, southeast of Iraq. They gave good results in detecting reef buildups and confirmed the existence of the stratigraphic hydrocarbon trap that was not obvious in the conventional seismic amplitude sections. They display several seismic criteria in attribute sections for recognizing reef buildups and hydrocarbon accumulation, such as phase reversal, low frequency, and high amplitude variance. The seismic attributes emphasized that the stratigraphic trap of reef rudist buildups with hydrocarbon content is constricted in the upper part of the Mishrif Formation (Cenomanian-Early Turonian) the vicinity around productive well Dujaila-1. It is located at a time from -1730 ms in the Top Mishrif to underneath at a time -1775 ms, which has correspondent the depth 2825 m to 2887.5 m, respectively. This stratigraphic trap covered 70 km2 (length is 10.0 km in direction N-S, and the width is about 7.0 km in the E-W direction). The enclosure of the stratigraphic trap extends about 7 km towards SW from the well Dujaila-1 and did not reach well Dujaila-2 (Du-2). That may explain why it was dry. As a result, the circular region around well Du-1 of a radius of about 4 km, and the area extended about 7 km toward SW from well Du-1 represent a zone of low risk-drill for new exploration wells.
The reservoir units of Mishrif Formation in Majnoon oil field were studied by using available wireline logs (gamma ray, porosity and resistivity) and facies that derived from core and cutting samples for three wells including Mj-1, Mj-15, and Mj-20. The reservoir properties were determined and interpreted by using IP software. The results showed that unit D have the best reservoir properties due to high effective porosity, low water saturation and very low volume of shale. Furthermore, a large part of this unit was deposited in shoal environment. The other reservoir units are then graded in reservoir properties including units B, A, F & E respectively, except unit C, which is considered as a cap unit, because it consists of rest
... Show MoreThe Amarah Oil field structure was studied and interpreted by using 2-D seismic data obtained from the Oil Exploration company. The study is concerned with Maysan Group Formation (Kirkuk Group) which is located in southeastern Iraq and belongs to the Tertiary Age. Two reflectors were detected based on synthetic seismograms and well logs (top and bottom Missan Group). Structural maps were derived from seismic reflection interpretations to obtain the location and direction of the sedimentary basin. Two-way time and depth maps were conducted depending on the structural interpretation of the picked reflectors to show several structural features. These included three types of closures, namely two anticlines extended in the directions of
... Show MoreThree-dimensional seismic reflection study was conducted for the Eastern
Baghdad oil field which is located in the middle part of Iraq within Al-Madaaen
province that belong to Baghdad governarate, South of Diyala River , this field
includes two southern parts (S1 and S2), the study area was about 781.905 km 2 for
the upper Cretaceous age, synthetic seismogram was generated from data of EB-5
and EB-1 wells. Saadi reflector was picked and identified to determine the Hartha
Formation. The seismic sections and time slice maps confirmed that the upper
Cretaceous age was affected by faults and the indicators of faults ended within
Hartha Formation and continue to the deeper formations with increasing intensity.
The
This study deal with structural and stratigraphic analysis of the seismic reflection data for Hartha Formation at Nasiriyah field, the area of seismic data is about (1237) km2. Nasiriyah oil field is located in Dhi Qar Governorate, southern Iraq, and the oil field is located to the East of Euphrates River of about (38) km northwest of Nasiriyah city. which includes twenty-four (24) wells. In some wells there are oil evidences in Hartha Formation at Nasiriyah oil field, for this reason, Hartha Formation is studied.
Two reflectors are picked (top and bottom Hartha) they are defined by using synthetic seismograms in time domain for wells (Ns-1, and 3). Time and depth of Hartha Formation are drawn using velocity data of reflectors. The st
The Kumait Oil field was interpreted using 3-D seismic data from Oil Exploration company. The Shuaiba Formation (Cretaceous Age) reflector is detected.Structural map of formation is prepared to obtain the location and direction of the sedimentary basin and shoreline. Depth maps was drawn depending on the structural interpretation of the picked reflector and show several structural feature as closures.The seismic interpretation of the area approves the presence of some stratigraphic features in the studied formation. Some distributary mound and flatspot were observed within the study area, but they are not continuous due to the tectonic effects. These activity elements give reasonable explanation for the hydrocarbon distributi
... Show MoreThe aim of this study is to determine and evaluate the units and subunits of Mishrif Formation in Garraf oil field 85 km north of Nasiriyah city depending mainly on the geophysical well logging data and other amiable geological information. The sets of the geophysical well logs data acquired from GA-4, GA- AIP, GA- B8P, GA-3 and GA-5 wells of Garraf oil field are used to determine the petrophysical and lithological properties for each zone in Mishrif Formation to locate, define and evaluate hydrocarbon production from each zone in the reservoir which is also known as formation evaluation. The digitization was done by using Didger software and the interpretations were made using Interactive Petrophysics Program v 3.5 and Petrel software.
... Show MoreThis study is achieved in the local area of the Eridu oil field, where the Mishrif Formation is considered the main productive reservoir. The Mishrif Formation was deposited during the Cretaceous period in the secondary sedimentary cycle (Cenomanian-Early Turonian as a part of the Wasia Group, a carbonate succession widespread throughout the Arabian Plate.
The Mishrif Formation already have been evaluated in terms of depositional environments and their diagenetic processes. Here, it will test the previous conclusions with petrophysical properties delineated by using well logging. The results show there is a fully matching with two reservoir units (MA and MB). Dissolution and primary porosity are responsible for f
... Show MoreThe estimation of rock petrophysical parameters is an essential matter to characterize any reservoir. This research deals with the evaluation of effective porosity (Pe), shale volume (Vsh) and water saturation (Sw) of reservoirs at Kumait and Dujalia fields, which were analyzed from well log and seismic data. The absolute acoustic impedance (AI) and relative acoustic impedance (RAI) were derived from a model which is based on the inversion of seismic 3-D post-stack data. NahrUmr formation’s sand reservoirs are identified by the RAI section of the study area. Nahr Umr sand-2 unit in Kumait field is the main reservoir; its delineation depends on the available well logs and AI sections information. The results of well logging i
... Show MoreThe structural division and stratigraphic estimation of the perceptible geological basin are the most important for oil and gas exploration. This study attempts to obtain subsurface geology in parts of east Nasiriya, southern Iraq using of seismic data and some adjacent well information for structural and stratigraphic interpretation. To achieve this goal, 2D seismic data in SEG-Y format were used with velocity and logging data. The seismic profile is then interpreted as a two-dimensional (time domain and depth domain) contour map, which is represented as a real subsurface geology.
Reflectors from the Mishrif and Yamama Formations (Cretaceous period) were detected. According to the structural interpretation of the sel
... Show MoreThis research represents a 3D seismic structural study for 602.62 Km2 of Dujaila
Oil Field which is located 55 Km Northwest of Mysan province and 20 Km Southwest
of Ali-AlSharki region within unstable Mesopotamian basin.
Synthetic traces are prepared by using available data of two wells (Du-1, Du-2), in
order to define and pick the reflectors. Two reflectors are picked that represent the top
and bottom of Mishrif Formation, in addition to five units within this Formation are
picked, they named Units 1, 2, 3, 4, and 5.
Time maps for the top and bottom of Mishrif reflectors are drawn to get the
structural picture, these maps show general dip of layers toward NE, and thus, there
are two enclosure domes in the midd