The Paleocene-Early Eocene sequence is represented by Aliji and Umm Er Radhuma formations, while the Middle-Late Eocene sequence is represented by Jaddala and Dammam formations. The Rus Formation has been described and its basin was analyzed separately because it was deposited during the regression period (Middle Eocene), which is a transitional period between these two cycles.
This study includes analysis of the geohistory of this succession, interpretation of the changes of the accumulation, and calculation of subsidence rates. The results were compared with the space available to explain the basin development. The study site included the boreholes of Garraf-84 and 92, Halfaya-1, Nasirya-13 and 40, and Noor-5 at th
... 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
... Show MoreThe study of the geochemical characterization of sandstone rocks contributes to understand the nature of the source rocks, their tectonic setting and the effects of paleoclimate and paleo-weathering. Accordingly, twenty sandstone samples from the red sandstone units of the Gercus Formation were collected from the northeastern limb of Safin Anticline at Shaqlawa Area – Northern Iraq. The studied sandstone samples show depletion in major, trace elements contents, except for CaO, MgO and Ni, Co and Cr respectively, and general depletion in the rare earth elements (REE) contents. Major element geochemistry indicates that the red bed sandstones of the Gercus Formation are of an oceanic island arc (OIA) tectonic setting. On the other
... Show MoreThe Paleocene-Eocene Thermal Maximum (PETM) event, which represented a sudden and abnormal rise in temperature during the early Cenozoic Era, is regarded as one of the most important global geologic phenomena. Two important index microfossils (nannoplankton and Ostracoda) were utilised to understand and predict the paleoenvironment and describe the changes during this period. The basis of the study was 12 cutting samples taken from Aaliji and the lower part of Jaddala formations of a subsurface section of (Ba-8) borehole in central Iraq. Some geophysical data were used to determine the upper and lower contacts of the Aaliji Formation and define the shale rate in the studied formations. The micropaleontologic investigation reveals
... Show MoreThis research deals with study of the Petrology and mineralogy of the Rus and Jil Formations at Najif and Al-Muthanna Governorates, Southern Iraq. The Rus Formation consists mainly of evaporites and subordinate carbonates. The evaporites are characterized by nodular structure (compound wispy, wispy, structureless and mosaic structures) with some laminated structure at the studied sections. Compound wispy to wispy structure are the dominant structures. The Jil Formation consists almost entirely of carbonate. The carbonate rocks are dolomitic limestone and dolomite beds, massive, fossiliferous, cavernous sometime friable and bioturbated in its lower part. The Jil Formation contains evaporites as thin beds, sometimes nodular and contains se
... Show MoreThis research deals with study of the Petrology and mineralogy of the Rus and Jil Formations at Najif and Al-Muthanna Governorates, Southern Iraq. The Rus Formation consists mainly of evaporites and subordinate carbonates. The evaporites are characterized by nodular structure (compound wispy, wispy, structureless and mosaic structures) with some laminated structure at the studied sections. Compound wispy to wispy structure are the dominant structures. The Jil Formation consists almost entirely of carbonate. The carbonate rocks are dolomitic limestone and dolomite beds, massive, fossiliferous, cavernous sometime friable and bioturbated in its lower part. The Jil Formation contains evaporites as thin beds, sometimes nodular and contains se
... Show MoreHydrogeological investigation and water budget calculation of Koi Sanjaq basin is carried out. This investigation includes the determination of the aquifer types extending through the study area and flow direction as well as aquifer hydraulic properties values. Three main unconfined aquifer types were distinguished , they are (Pilaspi), , (Bihassan-Muqdadiya and Fatha –Injana) Formations , where the flow map of the unconfined aquifers shows that the flow direction is from northern and northeastern parts towards the south and southeastern parts i.e. .Lesser Zab River. Analysis of pumping test data of 9 selected wells from unconfined aquifers show that T values range from 1.51m2/day to 64.4 m2/day revealing the great variations in the aq
... Show MoreLate Paleocene –Early Eocene algae and benthic foraminifera were identified
from the Sinjar Formation that crop out in three selected section from northern
Iraq. The selected sections: (Derbandikhan ,Qara dagh, Wara Mali has been
measured in the field and closely sampled to undertake details. A number of (131)
samples were collected illustrating all the lithological changes along the sections,
The limestone in the studied section is rich in algae and large benthic foraminifera,
The investigation of the thin sections allowed us to identify the (47 ) species of
foraminifera and (34) species of algae , Five biozones were distinguished for algae
which are :a- Amphiroa iraquensis range zone ,b- Trinocladus perplexus
The Pila Spi Formation (middle – late Eocene) was studied in terms of field character, Petrography and geochemistry from two outcrops (Bakhar and Bani bawy) sections, Northern Iraq. The field studies showing massive, lithified limestone to marly limestone high effected by dolomitization. The petrography studies shows that most of the skeletal grains was destroyed due to digenetic processes specifically the dolomitization, and the vast majority of carbonate rocks are mudstone and few beds of wackestone. The geochemical study reveals low CaO% and high MgO% content due to the intense effect of dolomitization, and the carbonate rocks was classified as impure limestone generally of slightly calcareous dolomite. Ca/Mg and Sr/Ca ratios have b
... Show MoreSynthesis of sedimentologic, paleocurrent, and organic geochemistry data of the Lower Permian Ga’ara Formation from the Western Desert, western Iraq, shows good hydrocarbon potentiality and deposition by high sinuosity and mixed-load channels, likely by a meandering river system. The Ga’ara Formation includes kaolinitic mudstone beds of various colors and channelized quartzitic sandstone beds. Based on the lithofacies identification, five lithofacies associations have been recognized: channel-floor, point-bar, abandoned channel plug, crevasse splay, and interchannel flood basin. In addition, the paleocurrent analysis and sandstone percentage map indicate a variation of the paleoflow spatially and temporally with a general di
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