The current study deals with microfacies and the depositional environment of the Lower Cretaceous Sarmord Formation at selected sections in Sulaimani and Erbil Governorates, northern Iraq. The Sarmord Formation alternates rhythmically between yellowish grey marly limestones and grey black marls. These lithologies are observed in all studied sections of Sarmord Formation in northern Iraq. Petrographic investigation of this study based on 240 thin sections demonstrated that the carbonate constituents are mainly composed of skeletal and non-skeletal grains. The skeletal grains include a variety of foraminiferas (planktonic and benthonic), bioclasts, calcispheres, ostracods, radiolaria, echinoderms, sponge spicules, ammonoids and be

The present study is concerned with Biostratigraphy of the Early-Middle Miocene outcrops of Jeribe Formation in the Zurbatiyah area, Wasit Governorate, Eastern Iraq. Forty-two Samples collected from Shur Sharin and AL-Hashima outcrop sections. The fossil content is rich in large and small benthic foraminifera; Twenty-one species and genus are identified in this study, in addition to coral, gastropoda, pelecypoda, ostracoda, alge, echinoid and shell fragments. According to the presence of benthic foraminifera, two Biozone have been identified in the Jeribe: Austrotrillina asmariensis-Dendritina rangi Concurrent Zone and Borelis melo curdica range zone.The age of the Formation determined as Early-Middle Miocene depending on these Bioz

     The Hartha Formation has been investigated from a biostratigraphic view in three subsurface sections in the Nasiriyah Oil field, wells Ns1, Ns3, and Ns4, South of Iraq. Hartha Formation is composed of limestone and has various areas of intense dolomitization alternating with marly limestone. The formation ranges in thickness from 126 to 182 meters. Thirteen large and small benthic foraminifer species and genera are identified from Hartha Formation. Based on the large benthic foraminifer's assemblage, one distinct biozone was recognized after an examination of the paleontological datum in the investigated area showed that the studied wells contained a diversity of foraminiferal species, the larger foraminifers biozone was propose

Seismic data interpretation study has been done for Mishrif Formation in Nasiriyah oil field at the southern part of Iraq in order to update the structural image of Mishrif reservoir which is currently the main unit bearing the oil in subsurface area covered about (447) km2. This study is achieved by using Petrel, IP, and other approval software. Seismic to well tie method in conventional qualitative interpretation used to re-identify the top and bottom of the Mishrif reservoir which converted into structural depth maps and then followed by constructing and developing 3-D structural model helped to understand the vertical and lateral thickness extensions heterogeneity of Mishrif Formation in the field. The cap rock (CRI) has thickness ra

     The current study included interpretations of the three-dimensional seismic survey data of the Najaf-Karbala region, which was recently implemented by the Fifth Amphibious Seismic crew of the Oil Exploration Company for the period from 30/1/2016 to 13/10/2017. The total area planned to be covered by the three-dimensional survey program was about (3340 km ²). The Zubair reflector was picked, interpreted, and tracked within the region. The faults affecting this reflector were captured. The reflector's temporal, velocity, and depth maps showed the presence of structural closure features in the southeast of the region and extensions to the structural noses to the northwest of the study area. The structural maps showed a general ten

Gas 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

     The 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

     The Hartha Formation (age Late Campanian – Early Maastrichtian) is considered an important oil reservoir in Iraq. The petrography and the diagenetic features were determined based on the analyses of 430 thin sections from selected wells within Balad and East Baghdad oil fields, Ba-2, Ba-3, EB-53, Eb-56 and EB-102.

The most important and common diagenesis processes that affect Hartha Formation include Cementation, Neomorphsim, Micrtitization, Dolomitization, Compaction, Dissolution, and Authigenic minerals. This diagenesis deformation on Hartha Formation has overall accentuated the reservoir quality heterogeneity.

The reservoir quality evolution is affected by destruction by grain compaction mechanical and chemica