This study is achieved in the local area in 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 and widespread throughout the Arabian Plate. There are four association facies are identified in Mishrif Formation according the microfacies analysis: FA1-Deep shelf facies association (Outer Ramp); FA2-Slope (Middle Ramp); FA3-Reef facies (Shoal) association (Inner ramp); FA4-Back Reef facies association. Sequence stratigraphic analysis show there are three stratigraphic surfaces based on the abrupt changing in depositional environments, one of them ((Mishrif –Kifl unconformity) are regionally correlated with the other equivalent formations in surrounding countries within the Arabian Plate. And intra- Mishrif two surfaces are maximum flooding surfaces which represents the deepening up-ward association facies. Two major sequences are identified based on the behaviors of facies association within a sequence of stratigraphic boundaries and system tracts. These sequences include sequence I and sequence II.
The Yamama Formation belongs to the late Berriasian-Aptian succession, which was deposited during the Lower Cretaceous period within the main shallow marine depositional environment.
Petrographic study and microfacies analysis enabled the recognition of six main microfacies for three association facies. These are the Semi-restricted, Shallow open marine and Shoal environments. The study succession represents deposition of three third order cycles, these cycles where deposited during successive episodes of relative sea level rises and still stand.
The presence of shoal association facies (oolitic packstone microfaces) between the Sulaiy and Yamama formations refer to continue the deposition during the same stage, and may s
... Show MoreAhdeb oil field is located in the central block of Mesopotamia plain in Iraq. It has three domes AD-1, AD-2, and AD-4.The current study represents characterization of carbonate Mishrif reservoir (Cenomanian-Early Turonian) in three wells (AD-A,AD-B,AD-C) at southern dome of Ahdeb oil field. Petrophysical properties were calculated using available well logs data such as neutron, density, sonic, gamma ray, resistivity and self-potential logs. These logs are digitized and then environmental corrections and interpretations were carried out using Techlog software. Petrophysical parameters such as shale volume, porosity, water saturation, hydrocarbon saturation, bulk water volume, etc. were determined and interpreted and illustrate
... Show MoreA surface section of the Gercus Formation (Middle-Late Eocene) was studied in Berafat area, Dohuk Governorate, Northern Iraq. The Gercus Formation consists of a mixed siliciclastic sediments, evaporates and carbonate sequences in the studied region, predominantly in the upper and middle parts. Nevertheless, it usually consists of upward-fining carbonate-rich sandstone cyclothems, marl, conglomerate and siltstone along with a gypsum lens and thin micrite carbonate beds. The Gercus Formation was deposited in delta and delta front of occasionally depositional environment which is represented by red-brown claystone and reddish-brown mudstone lithofacies. Cross bedded pebbly sandstone, trough cross-bedded sandstone and lamin
... Show MoreThe Nahr Umr Formation is considered one of the main reservoirs produced in southern Iraq. It is one of the important siliciclastic deposits of the Cretaceous sequence of Iraq oilfields. Zubair oil fields ZB-190 and ZB-047 were chosen to study areas. This study depends on the available core and cutting samples to determine the facies analysis, depositional environments, petrographic characteristics and diagenesis processes. Based on the description of the core and the borehole, six types of facies were distinguished in the Nahr Umr Formation, resulting in an intercalated sandstone and shale with a thin layer of siltstone. The petrographic study of the clastic part of the Nahr Umr Formation showed that the sandstone is composed m
... Show MoreThe Early Jurassic (Liassic) sequence crops out in numerous anticlines of the high folded zone of north and north-east Iraq and in the Rutba subzone (including Ubaid Formation) in west Iraq. The present study deals with siliciclastic / carbonate rocks of the 58 m-thick Ubaid Formation at Zor Hauran valley in south western Iraq. The formation consists of two parts; the lower part is composed of pebbly coarse sandstone and greenish to yellowish soft marl alternated with marly dolostone, while the upper part is characterized by light brown, well bedded dolostone, with stromatolite structure in some locations. Oval, light to dark brown nodules of chert are also present.
A detailed field lithological desc
... Show MoreThe seismic method depends on the nature of the reflected waves from the interfaces between layers, which in turn depends on the density and velocity of the layer, and this is called acoustic impedance. The seismic sections of the East Abu-Amoud field that is located in Missan Province, south-eastern Iraq, were studied and interpreted for updating the structural picture of the major Mishrif Formation for the reservoir in the Abu-amoud field. The Mishrif Formation is rich in petroleum in this area, with an area covering about 820 km2. The seismic interpretation of this study was carried out utilizing the software of Petrel-2017. The horizon was calibrated and defined on t
... Show More3D seismic reflection study was applied to Abu Amood oil field which is located at the southern part of Iraq within DhiQar province that carried out by oil Exploration Company to an area of 1534.88 Km2 for studying Nahr Umr Formation. Synthetic seismogram was prepared by using available data of well (AAM-1) in order to define and picking the reflectors on the seismic section. These reflectors are (Top of Nahr Umr Formation and middle unit of Nahr Umr Formation which represents the layer of sand). The seismic section time slice maps confirmed that the Nahr Umr Formation was not affected by faults and the faults may probably present in the Ratawai and Yamama Formations, where the variance attribute applied on seismic sections showed that t
... Show MoreThe Barremain-Aptian succession represented by two types of deposits, Clasits deposits of Zubair Formation. This formation is the most significant sandstone reservoir in Iraq, Deposited in fluvio- deltaic, deltaic and marine environments during the Barremain to Early Aptian age.
The area of study is located in the Mesopotamian Zone at S
The Barremain-Aptian succession represented by the Clasits deposits of Zubair Formation. This formation is the most significant sandstone reservoir in Iraq which deposited in fluvio- deltaic, deltaic and marine environments during the Barremain to Early Aptian age. The area of study is located in the Mesopotamian Zone at Southern part of Iraq which represented by five oil fields (Nasira, L
... Show MoreThis research deals with the study of the types and distribution of petrographic microfacies and Paleoenvironments of Mishrif Formation in Halfaya oil field, to define specific sedimentary environments. These environments were identified by microscopic examination of 35 thin sections of cutting samples for well HF-9H as well as 150 thin sections of core and cutting samples for well HF-I. Depending on log interpretation of wells HF-1, HF-316, HF-109, IIF-115, and IIF-272, the sedimentary facies were traced vertically through the use of various logs by Petrel 2013 software in addition to previous studies. Microfacies analysis showed the occurrence of six main Paleoenvironments within Mishrif succession, represented
... Show MoreThe current research studies the depositional setting of the Jeribe Formation in the south Mosul area of northern Iraq, which is tectonically located in the Low Folded Zone characterized by the deposition of limestone and marly limestone of the Jeribe Formation during the Middle Miocene. Petrography has provided a diversity of fauna such as benthonic foraminifera (Miliolid, Peneroplis sp., Dendritina sp. and Borelis melo curdica) in addition to Red Algae and Mollusca. The Jeribe carbonates were affected by various diagenetic processes such as dolomitization, neomorphism, cementation, anhydritization, compaction and dissolution. Many microfacies have been identified, including lime mudestone, wackestone, packstone and Milioldal
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