Shiranish formation has been divided into two microfacies units: 1 - Many biowackestone facies and 2 - maly packstone using planktonic foraminifera and other carbonate components in the rock cutting and core slides. Microfacies reflect marin deep shelf margin in the lower part of the formation, the upper part was deeper. The thickness of the formation is determined, depending on addition to the presence of echinoderm framents debris and spines. This is in disagreement with the 195 ft thickness reported by the Oil Exploration Company The age of the formation is estimated depending on the recognized biostratigraphic zone using the index fossils to be Upper - Middle Mastrichtion.
This study deals with establishing the depositional environment of the Fatha Formation through facies analysis. It also deals with dividing the formation into units based on the rhythmic nature. Data from selected shallow wells near Hit area and deep wells at East Baghdad Oil field are used. Five major lithofacies are recognized in this study, namely, greenish grey marl, limestone, gypsum (and/or anhydrite), halite and reddish brown mudstone (with occasional sandstone).The limestone lithofacies is divided into three microfacies: Gastropods bioclastic wackestone microfacies, Gastropods peloidal bioclastic packstone, and Foraminiferal packstone microfacies.The lithofacies of the Fatha are nested in a rhythmic pattern or what is known as sh
... Show MoreThe study intends to well logs interpretation to determine the petrophysical parameters of Euphrates Formations in Ajeel Oil Field. The petrophysical properties have been determined from well logging, Euphrates Formation in terms of reservoirs units, consist of two Petrophysical properties. Total porosity, effect porosity and secondary porosity have been calculated from neutron, density, and sonic logs. secondary porosity is high and it's resulted from diagenesis processes in the formation. From RHOB-NPHI and N/M cross plot, Euphrates Formation composed mainly from Limestone and dolomite with nodules of anhydrite. Dhiban Formation composed mainly of anhydrite, so it's represented the cap rocks for Euphrates Reservoir were recognized base
... Show MoreThis study deals with the petrology of Injana Formation (Upper Miocene) at
Zawita, Amadia and Zakho areas. The sandstone of Injana Formation is of two
typesnamely, litharenite and feldspathiclitharenite. The rock fragments of Injana
Formation are mostly sedimentary and hence the sandstones are classified as
sedarenite and more specifically chertarenite owing to the predominance of chert
rock fragments. The sandstone is mineralogicallysubmature rangingfrom
mechanically and chemically stable tounstable. The petrographic studies reveal
nearness of source area with arid to semi-arid climate. The source rocks are
sedimentary, low- to medium-grade metamorphic and basic volcanic rocks. They are
mostly supplied from th
The Hartha Formation is one of the important formations deposited during Late Campanian age.
The present study deals with four boreholes (EB-53, 54, 55 and 56) within the East Baghdad oil field to diagnoses the microfacies and interpret the depositional environments.
Six major microfacies were recognized in the succession of the Hartha Formation. Their characteristic grain types and depositional texture enabled the recognition of paleoenvironment. There are Orbitoides wackestone-packstone , Orbitoides - miliolid wackestone, Peloidal and Pellets - echinoderm wackestone to packstone, Peloidal wackestone to packstone, Pelletal wackestone to packstone, and Planktonic foraminifera wackestone-packstone.
Four assoc
... Show MoreYamama Formation is an important sequence in southern Iraq. Petrographic analysis was used to determine and analyze the microfacies and pore types. The diagenetic processes and the impacts on the petrophysical properties of the rocks were also identified. The petrographic identification was based on data of 250 thin sections of cutting and core samples from four wells that were supplied by the Iraqi Oil Exploration Company (O.E.C). The present study focuses on the depositional environment and the microfacies analysis of Yamama Formation. The results revealed several types of microfacies, including peloidal wackestone-packstone, algal wackestone-packstone, bioclastic wackestone-packstone, fo
... Show MoreSedimentary structures of Gercus Formation in NE Iraq was little studied in the last decades. In this study the identified sedimentary structures display alternative graded and fining upward cycles, load and flute casts, submarine channels, sand and clay balls and pillow structures, convolute and slump beddings, of marine turbidity origin. The foreland part of Tethys basin characterized by deep marine Tanjero and Kolosh Formations followed by the Gercus formation with conformable relationships. The Eocene aged Flysch comprises predominantly litharenitic sandstones and interbedded mudstones, both of turbiditic affinities and most likely derived from a NE Arabian Plate source. The sediments provide excellent examples of distal fan sands as
... Show MoreOne of the most important and common problems in petroleum engineering; reservoir, and production engineering is coning; either water or gas coning. Almost 75% of the drilled wells worldwide contains this problem, and in Iraq water coning problem is much wider than the gas coning problem thus in this paper we try to clarify most of the reasons causing water coning and some of applicable solutions to avoid it using the simulation program (CMG Builder) to build a single well model considering an Iraqi well in north of Iraq black oil field with a bottom water drive, Coning was decreased by 57% by dividing into sub-layers (8) layers rather than (4) layers, also it was decreased (Coning) by 45% when perforation numbers and positions was chang
... Show MoreThe research aims to assess the claystone exposed in the Nfayil Formation (Middle Miocene) for Portland cement (P.C.) manufacturing based on mineralogy and geochemistry. The importance of the study is to avoid the miming of the agricultural soils that are mining now for the cement industry. Claystones of Nfayil Formation and the limestone of the Euphrates Formation were used to design the raw mixture as clay to limestone (1:3). The chemical composition (%) of the designed mixture was calculated using the Alligation Alternative Method (A.A.M.) as CaO (65.52), MgO (1.05), SiO2 (21.65), Al2O3 (7.43), Fe2O3 (2.62), Na2O3+K2O (1.52) and SO3 (0.26), which are suitable for P.C. The lime saturation factor (LSF = 92.8), silica saturation fac
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