Iraqi Bulletin of Geology and Mining

The lithology of the Govanda Formation (Miocene) at Gali Baza locality, northeastern Iraq consists of massive conglomeratic bed at the base, grading upward to thin to medium bedded calcareous sandstone, sandy limestone, calcareous shale, and thin siltstone beds. The petrographic study of clastic and carbonate rocks, based on 21 thin sections, indicates that the major components are different kinds of rock fragments, quartz, altered feldspar and mica for the clastics and non- and/ or low-skeletal grains for the carbonates. The study showed that compaction is the most common diagenetic process affecting in the studied samples, appearing in the form of penetration between grains and grain deformation. Accordingly, it is suggested that the deposition of the Govanda Formation, in the studied Gali Baza section, had taken place in a littoral environment with terrigenous clastic supply.

The Early Jurassic sediments from Alan, Mus and Adaiyah formations have been studied in oil exploratory well M-2, Miran Oil field, Sulaimaniyah Governorate, Kurdistan Region, Iraq. Three techniques were used for determining hydrocarbon generation potentiality for these rock units; Rock-Eval Pyrolysis, microscopic study, and Infrared spectrometry. The Alan Formation has high TOC wt.% content, ranging between 1.47 and 1.82 (average 1.63), and Mus Formation with 0.85 and 1.75 (average 1.3), while the Adaiyah Formation samples are totally with low TOC wt.% ranging between 0.08 and 0.47 (average 0.30). Although the Rock-Eval Pyrolysis data show good genetic potential of the Alan and Mus formations, the potentiality of dry gas generation is only the chance for generating hydrocarbons if the organic matter reaches the mature stage. Also the Rock-Eval data reveal the type of kerogen is mostly type III and IV and the organic matters are still in immature stage except one sample from Adaiyah Formation. The organic matter within these sediments is amorphous and there are neither palynomorphs nor phytoclasts. These organic matters also are very small and have no fluorescence, which mostly of gas-prone type with no possibility for oil generating. Five kerogen samples were selected and analyzed by Infrared Spectrometer. The results from these samples show small variation outcomes with Rock-Eval data as the kerogen type of Alan and Mus formations are mostly type II, while samples of Adaiyah Formation are type IV kerogen, as determined by Rock-Eval pyrolysis. However the Infrared spectrometers also show vitrinite reflectance around 0.3% and less (Ro ≤ 0.3%) hence immature sediments, this result is coincides with the data of Rock-Eval pyrolysis. The results of all mentioned techniques were not exactly the same, and show some discrepancies, but mostly indicating to no potentiality for generating any oil and may be some gas generated from Alan and Mus formations. The Adaiyah Formation is inert and has no potentiality for generating any hydrocarbons in this well.

The attempts for determining the potentiality of Sargelu Formation adequately performed is by the application of various organic geochemical studies. The indications refer to this formation as being one of the most important source rocks and have its economic horizon generating the majority of oil and gas in Iraq. Basin modeling assist to declare the scope and will already perform the complementary view by acquiring all previous and current data, and create a new version of basin modeling, depending mainly on real and perfect studies that differ from the former studies that depends mainly on estimations because no rock samples were available, but in the undertaken study, rock samples (core and cuttings) were extracted from Butmah-15, Jabal Kand-1, Qara chuq-1 and Ajeel-8 oil exploratory wells.

One dimension petroleum-system modeling of key wells were developed using Integrated Exploration System (IES). PetroMod software to evaluate burial-thermal history, source-rock maturity, and the timing and extent of petroleum generation; interpreted well logs served as input to the models. The oil generation potential of sulfur-rich Sargelu source rocks was simulated using closed-system, Type IIs kerogen kinetics. Model results indicate that throughout northern Iraq generation and expulsion of oil from the Sargelu began and ended in the late Miocene.

At present, Jurassic source rocks might have generated and between 70 and 100 % of their total oil, or the model indicates that, the majority of Jurassic source rocks in Iraq have reached or exceed peak oil generation and most rocks have completed oil generation and expulsion except Jabal Kand-1, were defiantly unlike the other wells, is still generating today.

The present study is carried out on Abu Jir Fault across the Karbala – Najaf Plateau which is an outstanding fan-shaped geological feature located in the central part of Iraq on the boundary between the stable and unstable shelves. A clear variation of mineralogical composition percentages of quartz, calcite, feldspar, gypsum and gamma ray in both sides of the fault are recorded. The interpretation of magnetic maps; reduction to the pole and depth to basement (RTP and DTB) indicates three depressions, Al-Habbaniya, Al-Razzazah and Bahr Al-Najaf controlled tectonically by a NW – SE basement graben, and the plateau was a part of the subsided area. Gravity field along an ENE – WSW profile across Abu Jir fault indicates an elongated NW – SE positive anomaly of +0.9 mGal whose source is located at a depth of 3 Km, below the plateau, and the uplift is accompanied by faulting. Dibdibba Formation (Pliocene – Pleistocene) in the middle and southern Iraq has been developed in an active basin located along Abu Jir Fault. A large part of this formation is situated on the eastern edge of the Stable Shelf. The western block of the Fault was upthrown after the Pleistocene as a post-depositional tectonic episode forming an elevated area which had since been intensively eroded due to a new tectonism along the Abu Jir Fault. Sharp variations in mineralogy, gamma ray and geophysical parameters have been recorded on both blocks of the fault and are consistent with field evidence and confirm the new tectonics of Abu Jir Fault.

During the last decades, expansion of settlements into areas prone to landslides in Iraq has increased the importance of accurate landslide inventory and susceptibility studies. The Landslide inventory map is the spatial distribution of the gravity-induced mass movements. Susceptibility mapping provides information about hazardous locations and thus helps to potentially prevent infrastructure damages due to mass wasting. This study aims to assess the localization and size distribution of potential landslides, in addition to implement selected parameters to predict landslide susceptibility using remote sensing techniques in mountainous environments. The study covers the Qala Diza area, Kurdistan Region (NE Iraq), within the Zagros Fold – Thrust Belt, which includes the High Folded Zone (HFZ), the Imbricate Zone (IZ), the Zagros Suture Zone (ZSZ) and the Shalair (Sanandaj – Sirjan) Terrain.
The available reference inventory includes 353 landslides (representing a cumulated surface of 35.38 Km2) mapped from twelve Quick Bird scenes using manual delineation. The landslide types involve rock falls, translational slides, slumps and toppling which have occurred in different lithological units. At the beginning, cumulative landslide number-size distributions are analyzed using the inventory map. Then, twelve factors, mainly derived from a Digital Elevation Model (DEM) of Shuttle Radar Topography Mission (SRTM), as well as geological and environmental predicting factors were appraised. Logistic regression approaches are used to determine the landslide susceptibility (LS). The areas under the curve (AUC) of the prediction rate curve (PRC) for the landslide susceptibility shows that the accuracy of the map is about 85%. The results indicate that the Hypsometric Integral (HI), lithology and structure are the more significant factors in the detection of potential occurrence of landslides in the studied area.

The mineralogy and geochemistry of the Jeribe Formation are examined by XRF and XRD techniques. The formation belongs to the Miocene sequences, which are exposed in the eastern part of Iraq within the low folded Zone. Dolomite and calcite are the main minerals making the carbonate rocks of the formation with subordinate minerals of quartz and clay minerals (kaolinite, montmorillonite and illite).
Application of Ca/Mg ratio for classification of carbonate rocks reveals that the majority of the rock dolomitic in the formation. The molar ratios of certain trace elements of Mo/U, V/Cr and Ni/Co reveal Oxic-Redoxs conditions and Ca/Mg, Mg/Ca, and Ba/Ca ratios imply moderate salinity at the time of sedimentation. While Mg/Ca and Mn/Ca ratios infer low temperature at the carbonate deposition. Comparing the low Sr/Ca with the moderately high Ca/Mg ratios indicate that the dolomitization process played the main role in the diagenesis processes.
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Limestone of Avroman Formation in Halabja Governorate – Kurdistan Region, northeast Iraq were subjected to elemental and mineralogical analysis by X-ray fluorescence and X-ray diffraction, as well as petrophysical and mechanical study with the aim of accessing its extent as potential raw material for manufacturing Portland cement.
The results reflect rising the concentrations of CaO and loss on ignition, and the decrease of the concentrations of SiO2, Al2O3, Fe2O3, SO3, Na2O, K2O, and insoluble residue, According to these geochemical properties, the tested samples are reliable as carbonate component for cement industry. Mineralogical study shows that calcite is the main component of limestone samples which is more than 99% of the total constituent.
The petrophysical tests reflect the increase of total density, apparent specific gravity, and the decrease of porosity and moisture content of the samples and most of the studied samples are in agreement with natural ranges for carbonate rocks used in cement industry. The mechanical tests reflect high compressive strength of the studied samples and it can be concluded that the processes of crushing and grinding need a suitable force (energy) during the extraction of samples from the quarry.
The estimated raw mixture and clinker composition are calculated and the results show that all samples are in agreement with standard specification for production of Portland cement.

The work reports a procedure for the synthesis of γ-alumina from the Iraqi kaolin. Kaolin was transformed to metakaolin by calcination at 750 °C for 45 minute. γ-alumina powder was synthesized through extracting alumina from metakaolin via H2SO4 treatment and precipitation by ethanol, which produces aluminum sulfate of 99% purity. The precipitated aluminum sulfate was dried and calcined at 800, 850, 900 and 1000 °C to study the thermal decomposition of aluminum sulfate. The crystallinity and phase of the synthesized for the assignment of calcined samples was characterized by X-ray diffraction measurements, paving the temperature at which the aluminum sulfate is converted to γ-alumina nano particles. Pure alumina nanoparticle 98.81% was prepared by calcination of aluminum sulfate at 1000 °C for 2 hour. The specific surface area, pore volume and pore size for γ-alumina nano particles were determined by BET measurement i.e. 117 m2/gm, 1.1 cm3/g and 337.6 Å respectively. The size of the particles obtained were also calculated from BET analysis to be around 13 nm. The study revealed that the kaolin could be a promising material for the preparation of γ-alumina.