The 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 hand, the results revealed that the paleo-weathering of the source area of the Gercus Formation experienced intensive chemical weathering under humid and/or warm climate conditions. The maturity and paleoclimate conclusions of the studied samples suggest a low feldspar content and low values of K2O / Al2O3 ratio, which in turn resulted from the dominance of low grade metamorphic and sedimentary rock types in the source area.
The early Carboniferous Harur Formation from the Ora outcrop section of northern Iraq consists of black shale, calcareous shale and carbonate. The mineralogical and geochemical investigations (major and trace elements) of the black shale and calcareous shale units have been conducted to evaluate paleoenvironmental conditions including paleoclimate, paleoredox conditions, paleoproductivity, sedimentary rate, and to evaluate their effects on organic matter accumulation. The geochemical proxies such as the Chemical Index of Alteration (CIA), A-CN-K plot, Sr/Cu ratio, and the relation between the ratio of Ga/Rb and Sr/Cu suggest moderate to intense chemical weathering under humid conditions. The Rb/K and Sr/Ba ratios indicate a freshw
... Show MoreA mineralogical study using X-ray diffraction supported by scanning electron microscopic examination on the Paleocene- Eocene Kolosh and Gercus formations from northern Iraq is conducted to show the distribution of clay minerals and their paleoenvironmental implications. Smectite palygorskite, kaolinite, illite, and chlorite are commonly present in varying proportions within the Kolosh and Gercus formations. Association of smectite and chlorite in the claystone of the Paleocene Kolosh Formation refers to marine environment of this formation, whereas development of palygorskite fibers from smectite precursor may relate to post-depositional diagenesis. In addition, the abundance of illite and kaolinite in the Eocen
... Show MoreThe gravity and magnetic data of Tikrit-Kirkuk area in central Iraq were considered to study the tectonic situation in the area. The residual anomalies were separated from regional using space windows method with space of about 24, 12 and 10km to delineate the source level of the residual anomalies. The Total Horizontal Derivative (THD) is used to identify the fault trends in the basement and sedimentary rocks depending upon gravity and magnetic data. The identified faults in the study area show (NW-SE), less common (NE-SW) and rare (N-S) trends. Some of these faults extending from the basement to the upper most layer of the sedimentary rocks. It was found that the depth of some gravity and magnetic source range 12-13Km, which confirm th
... Show MoreThe Bouguer gravity and magnetic RTP anomalies data were used to detect the main tectonic boundaries of middle and south of Diyala Province, east Iraq. Window method was used to separate the residual anomalies using different space windows for the Bouguer and Magnetic RTP maps. The residual anomaly processed in order to reduce noise and give a more comprehensive vision about subsurface lineaments structures. Results for descriptive interpretation presented as contour maps in order to locate directions and extensions of lineaments feature which may interpret as faults. The gradient technique is used for depth estimation of some gravity source which shows that the sources depth range between (13.65
... Show MoreSedimentologic and facies evidences reveal a marine environment for the Gercus Formation. Facies analysis and associated sedimentary structures including graded beddings decide turbidity origin of the rocks. Marine environment is supported by the identifying glauconite and fossils types reported for the first time.
The formation composed of seven lithotypes; shale/claystone, mudstone, sandstone, carbonate, conglomerate, breccias and debris flow, which are arranged in repeated cycles of mixed siliciclastic-carbonate turbidites in a range of gravity-flow regime. The Gercus successions are grouped into four facies associations confirming marine depositional systems, these are (from bottom to top); slump siliciclastic-calciturbidites (dol
Five new ostracod species belonging to the subfamily Trachyleberidinae have been described. They are Paragrenocythere monilis and Peloriops levisulcata from the Maastrichtian of Iraq; Oertliella petraensis from the early Palaeocene (middle – late Danian) of Jordan; Reticulina syriaensis from the Palaeocene of Syria and Reticulina ninurta from the middle – late Eocene of Iraq.
The present study is focused upon the sedimentology and basin development of the Jeribe and Fatha Formations by using the field observations and microfacies analysis. The area of study situated in the Zurbatiyah area to the south of the Shur sharin valley about 21 km northeast of Badrah city to the southeast of Baghdad. This area lies within the Zagros foreland basin, and located between the Zagros mountains at the northeastern and the Arabian shield at the southeastern.
The studied succession which including the Jeribe and Fatha Formations were deposited within four associated facies for the Jeribe Formation and three for the Fatha Formation, as shown below: -
Jeribe Formation
... Show Moreالخلاصة لقد شكل المحافظون الجدد وهم بالأساس نخبة من المثقفين ومن السياسيين الأمريكيين كتلة ضغط كبيرة التأثير على الإدارة في عهد الجمهوريين. حمل هؤلاء المحافظون مشروعاً إيديولوجياً البسوه لسلطة الجمهوريين وهو يهدف إلى جعل أمريكا سيدة العالم من دون منازع خاصة بعد انهيار الاتحاد السوفييتي ونهاية الحرب الباردة. واكب هذا الحدث التاريخي الكثير من الأفكار ومنها (نهاية التاريخ)، وصراع الحضارات، وكذ
... Show MoreThe content of redox sensitive trace element (V, Co, Ni, and Mo) in the bituminous limestone of the Euphrates Formation (E. Miocene) and bituminous gypsum of the Fatha Formation (M. Miocene) in the Hit Abu-Jir village area, Anbar governorate were determined using Inductively-Coupled Plasma Mass Spectrometer (ICP-MS), in order to infer the origin of the hydrocarbon and the depositional conditions of the organic matter. Hydrocarbons species by using FTIR technique was identified as aliphatic, aromatic compound, hydroxyl acids, hydroxyl group, sulfoxide and sulfur. Bitumen occurrences in these formations is a result of the hydrocarbon seepages that moved up under high pressure along the Abu-Jir fault Zone, and then were intruded in the lime
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