During the Maastrichtian, the rudists and benthic foraminifera of Aqra Formation underwent two major radiations, the first beginning in early Early Maastrichtian and peaking in the late Early Maastrichtian, and sconed extending from the early Late Maastrichtian to a late Late Maastrichtian peak.The radiations were punctuated and separated by prominent extinction episodes, fit with global Maastrichtian mass extinction.The high level of rudist, endemism [90%] allows definition of true regional origination and extinction pattern; these may represent global pattern for rudists. Radiation and extinction patterns in the northern Iraq [Kurdistan Region] can be variously related to relative sea level fluctuation and the rate of food and clastic

      A seismic study was conducted to re-interpret the Qasab and Jawan oil field in northern Iraq, south of the city of Mosul, by reprocessing and interpreting many seismic sections of a number of field surveys that included the field area. Two reflectors are detected, represented by Hartha Formations which were deposited during the Cretaceous age and Euphrates Formation which was deposited during the Tertiary age in order to stabilize the structural image of this field. The study was achieved by reinterpreting seismic sections using the Petrel program, where time, velocity  and depth maps were prepared for the two formations.

The study showed that the Qasab and Jawan fields generally consist of a s

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

Six main microfacies are identified which are Lime Mudstone, Bioclastic Wackeston, Bioclastic Packstone-Wackestone, Bioclastic Wackestone- Mudestone, Pelagic Mudstone–Wackestone, Bioclastic Packstone -Grainston Microfacies in addition to their associated depositional environment. The diagenesis process have affected the Mishrif rocks and played a role in deteriorating reservoir porosity in well Ga-2 and enhancing it in well Ga1,3.These processes include: cementation, micritization, recrystallization,dissolution,compaction pressure solution and dolomitization.

Ten samples were collected from Injana and Mukdadiya Formations, representing 5 samples of fine grain sandstone (F) and 5 samples of very fine grain sandstone (VF). The heavy metals study showed that the opaque mineral recorded the highest percentage in comparison with other heavy metals. While, transparent minerals, including unstable minerals (Amphibole including Hornblend and Glaucophane) and (pyroxene including Orthopyroxene and Clinopyroxene), Metastable minerals including (Epidote, staurolite, Garnet, Kyanite) indicated metamorphic source, Ultrastable minerals (Zircon, Rutile, Tourmaline), Mica group (chlorite, biotite and muscovite). These accumulations indicate that the heavy minerals are derived from mafic igneous and metamorphi

Three-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

     Bai Hassan Oil field is considered one of the important north Iraq oil fields. The giant oil field of Bai-Hassan is located near Kirkuk City in North Iraq. The field consists of two domes (in SE – NW direction) Kithka Dome and Dauod Dome separated by a narrow saddle called Shashal saddle.

The current study is focused on microfacies analysis to interpret the stratigraphic sequence of the Palani Formation (early – lower Oligocene age), Baba, Bajawan and Tarjil Formations (middle Oligocene age).

The Bajawan Formation consists basically of five microfacies easily recognizable throughout the thin section. These microfacies are Lime Mudstone Microfacies, Miliolid Packestone Microfacies, Miliolid Grainstone Microfacie

Well log analysis of selected sections in southern Iraq revealed that primary porosity is the most effective parameters. Secondary porosity seems to be related mainly to dissolution and dolomatization. The Hartha Formation has good water saturation and low production except in the eastern and central part of the study area. Two reservoir units were recognized in Mj-2 whereas only one in Ga-1.
The values of velocity deviation in most wells show high positive deviation, this may indicate relatively high velocity in regard to porosity where pores are commonly not connected such as in interaparticle or moldic porosity. A positive deviation also may indicate low permeability. Negative deviation zone (Only in Ak-1) may represent caving or i

Mauddud Formation (Albian stage-the Early Cretaceous) is an important oil reservoir in Ratawi field of southern Iraq. Four wells, R T-2, R T-3, R T-6, and R T-7, located 70 km northwest of Basra, were selected to study microfacies properties and petrophysical associations with the probability of oil production. Seventy-seven core samples are collected, and thin sections for petrographic analysis. The self-potential, Gamma-ray, resistivity, and porosity logs are used to determine the top and bottom of the Mauddud Formation. Water saturation of the invaded and uninvaded zones, shale volume, and porosity were calculated. The study area results showed that the quantity of shale is less than 15% for most of the wells, and the dominant po

     The Zubair Formation is one of the major reservoirs of high production in the Rumaila oilfield, southern Iraq. The petrophysical properties analysis of the Upper Sand Member (Main Pay) of the Zubair Formation was conducted. The study includes results analysis of four wells distributed along the South Rumaila oilfield. Using a set of open well-logs, the main pay was divided into three main pay (AB, DJ and LN) units separated by two insulating shale units (C and K). The unit DJ was subdivided into three secondary reservoir units: D, F, H and the LN unit, which is split into L, M, and N. The research also includes the statistical analysis of the petrophysical properties, the calculation of the heterogeneity of the reservoir, and th