The stratigraphic sequence of Cenomanian-Early Turonian is composed of Ahmadi, Rumaila, and Mishrif formations in the Rifai, Noor and Halfaya Oil Fields within the Mesopotamian Zone of Iraq, which is bounded at top and bottom by unconformity surfaces. The microfacies analysis of the study wells assisted the recognition of five main environments (open marine, basinal, shallow open marine, Rudist biostrome, and lagoon); these microfacies were indicative of a normal lateral change facies from shallow water facies to deeper water and open marine sediments.

    Ahmadi Formation (Early Cenomanian) is characterized by open marine sediments during the transgressive conditions, and would be

      The reservoir characterization of Lower Qamchuqa (Shu'aiba) Formation (Aptian) is studied at the well BH-86 of Bai- Hassan Oilfield in Kirkuk area, Northern Iraq. The lithological study (of 91 thin sections) revealed that the formation consists of shaly limestone, a thin bed of marl within the limestone, and dolomitic limestone. Four petrographic microfacies were noticed Lime mudstone microfacies, Dolomudstone microfacies, Lime wackestone microfacies, subdivided into benthonic foraminifera lime wackestone submicrofacies and bioclasts lime wackestone submicrofacies, and the last microfacies is the Lime packstone microfacies, which is subdivided into pelloidal lime packstone submicrofacies and Orbitolina lime packstone microfaci

The 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

Suitability of groundwater for irrigation depends upon many constrains factors, these factors depend upon the dissolved salts during the flow of the recharge of the groundwater beside the aquifer constituents itself, from these factors (EC, SO4-2, Cl-, Na%, and SAR) .The spatial distribution of each constrain factor may show discrepancy from the another, so it is not possible to depend upon one factor. The aim of this work is to present a classification of the groundwater quality for agriculture including all the mentioned five factors, by using Arc GIS which provides tools to serve a purpose to create conceptual model for solving spatial problems. A set of conceptual steps used to build a model for suitability map of groundwater for irr

This study showed that the rock bed units of Fatha (M. Miocene) includes mold of fish fossils imprint on marly limestone; Injana (L. Miocene) includes large femur bone of Mastodont and large number of bone remains; and review study of Mukdadiya Formations (Pliocene) showed more than 21 mamalian species such as: Mastodont, Hipparion, Gazzella, Felidae, Bovidae, Antilopini, Caprinae, Crocodilia, and others. Those vertebrate fossils bones were deposited and preserved within rock bed units of fluvial and evaporite marine environments. Paleoenvironment of fluvial ecosystem made up of food chain, which were includes producer, herbivores as a primary consumer as Mastodon, Hipparion and Gazelle, carnivores as a secondary consumer as felidea and

Ostracode assemblages have been utilized for the study of the paleoecology of
the Maastrichtian – Upper Eocene succession (Hartha, Shiranish, Aaliji, Kolosh,
Jaddala and Avanah formations) in North and Iraq, represented by five sections,
including four boreholes, Anah well-2, Mityaha well-1, Makhul well-2,
Chemchemal well-2 and Jabel Sinjar outcrop section. According to the different
environmental factors affecting on the ostracode ecology, such as salinity, depth,
temperature, oxygenation, substrate and food supply; and depending on the
distribution of ostracode assemblages within the studied sections, nine ecofacies
have been recognized indicating shallow brackish or brackish- marine water, neritic
marine,

The purpose of this study is to elucidate the microfacies and the biozones present in the studied rocks as well as to determine their environments or deposition. The study depends mainly on the benthonic foraminiferal assemblages identified from (27) rock thin sections made available from an outcrop at Wadi Banat Al-Hassan area in the Upper Euphrates Valley. X-Ray diffraction was also used to determine the type of carbonate minerals present in the studied rocks.

This study involves microfacies analysis of the Kometan Formation from northeastern Iraq supported by detailed petrographic investigation for the main components and diagenetic processes using a petrographic microscope, scanning electron microscope (SEM), and X-Ray diffraction (XRD). The techniques have revealed that the formation includes two microfacies; lime wackestone and lime packstone microfacies which in turn are subdivided into seven sub-microfacies, that were deposited in the quiet and deep marine environment. Planktonic foraminifera (keeled and globular chamber types) are dominant, along with oligostegina in addition to subordinate benthonic foraminifera and fine-grained bioclasts. Calcite forms the main mineralogical compositi

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

The current study a accounts for the climate of the Diyala River Basin in Iraq where the climate is assessed depending on the most wellknown climatic classification. According to these classifications, it has been discovered that the area is located under Three climatic zones. The first zone is the semi humid or moderate, which covers the northern parts of the area. The second zone is the semi –dry climate which spreads over the middle part of the region. The third one, it extends over the southern parts and it is described as being dry .some maps were drawn to show the depth of rain fall for two successive periods. These maps indicate increase in the area of lands affected by the dry climate on account of the lands that used to lie