The Iraqi Geological Journal <p>The <strong><em>Iraqi Geological Journal (IGJ)</em></strong> is a peer-reviewed and indexed journal, issued twice a year in English by the Union of Iraqi Geologists (UIG).&nbsp;</p> en-US (Sameer R. Ahmed) (Sameer R. Ahmed) Sat, 01 Aug 2020 02:58:41 -0500 OJS 60 HYDROCHEMICAL EVALUATION OF THE AZRAQ UNCONFINED AQUIFER, JORDAN <p><strong><em>The groundwater hydrochemical characteristics of the Azraq Basin were investigated and evaluated statistically. The presence of an underground saline water body in the Qa’ Al-Azraq area has made this specific part of the basin. &nbsp;38 samples from 38 GW wells were collected to understand the GW hydrochemistry of the Azraq unconfined aquifer that is mainly composed of marl, evaporites, limestone and clay formations. The PCA analysis indicates that Na, Mg, Cl, Ca, and K contribute the variance in the chemical composition of the GW samples. Piper, Durov and Wilcox diagrams indicated that the water types are mainly earth alkaline with prevailing </em></strong><strong><em>SO<sub>4</sub></em></strong><strong><em> and Cl, and alkaline water with prevailing </em></strong><strong><em>SO<sub>4</sub></em></strong><strong><em> and Cl. The main processes in the basin are dissolution or mixing and reverse ion exchange in which Na and Cl are prevailing. The GW is mainly oversaturated concerning aragonite, calcite and dolomite as indicated by the excess input of Mg and Ca ions from the rock-water interactions, while anhydrite (CaSO<sub>4</sub>), halite (NaCl), and gypsum (CaSO<sub>4</sub>.2H<sub>2</sub>O) are generally undersaturated. The effect of the agricultural activities in the study area is reflected by the positive correlation between NO<sub>3</sub> and PC<sub>2</sub>. Wilcox diagram indicates that the samples are in the medium to very high salinity slots with the majority in the high salinity slot and in the low and medium alkali hazard zone, while few samples show high to very high alkali hazards. The simulated salinity for the next 30 years shows alarming danger and requires immediate attention as the Qa’ area is expected to become saline with TDS values of 2500 to 4600 mg/l, unsuitable to use for domestic and/or agricultural purposes.</em></strong></p> <p>&nbsp;</p> Sura Taha Al-Harahsheh, Marwan Al-Raggad, Ahmad Al-Shdaifat, Mohammad Al-Wreikat ##submission.copyrightStatement## Sun, 26 Jul 2020 00:00:00 -0500 INVESTIGATION OF SALT, ALUM CONTENT IN SOFT SOILS AND THEIR EFFECTS ON SOIL PROPERTIES: CASE STUDY IN COASTAL AREAS OF VIETNAM <p><em>Soft soil is widely distributed in Vietnam’s coast area, which normally contains salt, organic matters, and its properties can be affected by</em><em> the </em><em>saltwater</em><em> intrusion. This article presents experimental laboratories to investigate the salt, alum contents in some soft soils distributed in </em><em>the coastal areas </em><em>of Vietnam, and their effects on the properties of soft soil. To investigate the effect of salt content and pH values on soil properties, the soil was submerged into different solutions of salt content and pH value for 10 days before testing. The experimental results indicated that the average salt content in natural soils in the studied area changed from 0.31% to 1.58% and had a different level of salt contamination. I</em><em>n some places, the soil had a low pH value (pH&lt;4.5) and high sulfate content. The research also showed that the increase in salt and alum contents caused a decrease in undrained shear strength and an increase in liquid limit and compression index.</em></p> Nguyen Thi Nu, Nguyen Thanh Duong, Bui Truong Son, Phi Hong Thinh ##submission.copyrightStatement## Sun, 26 Jul 2020 00:00:00 -0500 APPLICATION OF TRIANGLES METHOD FOR QUANTITATIVE ESTIMATION OF MARL RESERVE IN EUPHRATES FORMATION, MIDDLE OF IRAQ <p><strong><em>The Raw materials are of great importance for producing a high-quality Portland Cement. Calcium, silica, and alumina are essential components of the initial mixture used for the manufacture of the Portland Cement.&nbsp; The marl bed in the Euphrates Formation at the quarries of the Kufa cement plant was proposed to be an alternative raw material to provide such components to the cement mixture. For this reason, nine boreholes were drilled in addition to three boreholes that had been previously drilled in the study area. The marl reserve was classified according to the Russian classification as a C1 category, and as a probable reserve according to the British classification and estimated as a reserve of 53 million tons by using the triangle method. Porosity (30.47%), Bulk density (1.73 gm/cm<sup>3</sup>) and compressive strength (3.59 N/m<sup>2</sup>) were measured and show the homogeneity of hardness can serve in the reduction of the electrical energy consumption and the wear of equipment productivity and increase the production of the mills, that are reflected eventually in the reduction of the final product cost.</em></strong></p> Salih Muhammad Awad, Mohanad R.A. Al-Owaidi ##submission.copyrightStatement## Sun, 26 Jul 2020 00:00:00 -0500 WELL LOGS DATA PREDICTION OF THE NAHR UMR AND MISHRIF FORMATIONS IN THE WELL NOOR-10, SOUTHERN IRAQ <p><strong><em>Well logs data are the most widely used data to evaluate subsurface rocks, their petrophysical properties include porosity, permeability and fluid saturation. They are essential for the hydrocarbon reserves estimations and perforation zones determination for production purposes and fields development. Well logging operations of the targeted reservoirs could not be done in NO-10 Well, Noor Oilfield, Southern Iraq due to some problems related to the well condition. The gamma-ray and sonic logs were the only recorded logs, while neutron, density and deep resistivity logs are missed. The missing neutron, density and deep resistivity logs of the Early Cretaceous Nahr Umr Sandstone and the Late Cretaceous Mishrif formations of the well NO-10 were produced and compared together using the Artificial Neural Network ANN in Petrel software. The results show that the total correlation of the ANN Nahr Umr model for the neutron, density and deep resistivity logs are 0.81, 0.49 and 0.51 respectively. Interestingly, the ANN Mishrif Formation model recorded 0.88, 0.92 and 0.81 for neutron, density and resistivity logs respectively. The results show excellent relationships between the original and the predicted logs in the Mishrif model, unlike the Nahr Umr model expect in ANN of the neutron log. It was expected that the total relationships are low in Nahr Umr due to the lithology variation that includes interbedded consolidated and unconsolidated sandstone interbedded with the shale. It is also observed that the gamma log shows low values and the caliper logs is smoothed in the Mishrif. In contrast, the Nahr Umr sandstone logs show that many washouts have occurred. Therefore, logs’ responses highly possible to be affected in the Nahr Umr Formation which leads to a decreasing in the coefficient of determinations. </em></strong></p> Abbas Kareem Abdulsahib Mohammed, Jawad K. Radhi, Sada Z. Ali ##submission.copyrightStatement## Tue, 28 Jul 2020 02:48:42 -0500 DIFFERENTIAL ENTRAPMENT OF CHARGED HYDROCARBON IN ALAN FIELD, NORTHERN IRAQ <p><strong><em>The Alan oilfield consists of three domes western, middle and eastern. Well Alan-1 and Well Alan-2 are drilled in the middle and western domes respectively. Oil fills the lower part of the Kurra Chine Formation (Late Triassic) in the middle dome while it occupies the upper part of the formation from the western dome; also, the gas and condensate fill the lower part of the formation in the western dome. Alan field consists of the lower and upper reservoirs of the Kurra Chine Formation separate by 220 m of anhydrite cap rocks. Alan structure develops at the end of Pliocene at the northwest ridge of the Mosul High. Source rocks of Triassic sequence, especially northwest Iraq, are matured and generate hydrocarbon that migrates laterally up-dip toward Alan structure. The folding plays an important role to trap the hydrocarbon in the lower reservoir. Western dome fills by gas and condensate completely until gas-oil contact reaches to the spill point between the western and middle domes. The oil is pushed toward the middle dome because it beyond and higher than the western dome. Another factor affected the hydrocarbon distribution in the lower reservoir was the erosion of about 800 m from overburden of Miocene sequence upward which was led to increase the void volume of porosity for the reservoir carbonate rocks. This increase allows to release of gas and push the oil to the middle dome. Two scenarios of hydrocarbon entrapment in the lower reservoir, the first one depends on the concepts of Gussow′s fill and spill, in which the source rock enters maturity levels after or within the formation of the structure. The second scenario is in which the development of structure after charge of hydrocarbons. The latter is the most widely accepted in the Alan field case.&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</em></strong></p> Nasser H.O. Alhadithi, Abdulkhaleq A. Al-Hadithy ##submission.copyrightStatement## Tue, 28 Jul 2020 02:49:39 -0500 CRUSTAL STRUCTURE BENEATH AL-REFAEI SEISMIC STATION – CENTRAL MESOPOTAMIA, IRAQ, USING RECEIVER FUNCTION TECHNIQUE <p><strong><em>&nbsp;</em></strong><strong><em>Al-Refaei district is one of the largest towns in Thi-Qar, southern Iraq. Tectonically, it is located in the central Mesopotamian zone of the Arabian plate. The crustal structure of this area was estimated to understand the geological and tectonic setting. From the data of the broadband seismic station (NSR1), which is part of the Iraqi Seismic Observatory the crustal velocity model was derived using the inversion of P-wave receiver functions (RFs). Data from this station was analyzed using the Computer Programs in Seismology. The results show two distinct discontinuities; these are the basement rock at a depth of 8km (Vs 2.63 km/s) and the Moho discontinuity at an approximate depth of &nbsp;46 km (Vs 3.79 km/s). The calculated velocity model can be used to locate earthquakes and build accurate Green Functions for the region in future studies.</em></strong></p> Ali Ramthan, Wathiq Abdulnaby, Najah Abd, Hanan Mahdi, Haydar Al-Shukri ##submission.copyrightStatement## Tue, 28 Jul 2020 02:50:31 -0500 MORPHOMETRIC ANALYSIS USING GEO-INFORMATION TECHNIQUES FOR DIFFERENT WATERSHEDS IN NORTHEASTERN PART OF ERBIL CITY, KURDISTAN REGION, NORTH IRAQ <p><strong><em>The present research attempts to study detail morphometric analysis of Harrir and Shaqlawa watersheds in the northeastern part of Erbil city, north of Iraq. The areas of the watersheds are 350 Km² and 223 Km² for Harrir and Shaqlawa, respectively. To achieve the aims of this study, the ALOS PALSAR Digital Elevation Model data, and Geo-information (Remote sensing and GIS) techniques were used for determining and analyzing morphometric parameters in terms linear, aerial and relief aspects. Several tools in ArcGIS 10.4 software were utilized for preparing and producing maps, analyzing and assessing various characteristics of the parameters. The main results show that there is a strong inverse relationship between stream order, number and length of the stream in the watersheds of the study area by R² values (R² = 0.78 and 0.81 of Harrir watershed and R² = 0.8 and 0.79 for Shaqlawa watershed, respectively). The watersheds are elongated in shape with dendritic, sub dendritic to parallel drainage patterns. Moreover, detail morphometric analysis shows that the watersheds have a low runoff, low permeable material, and moderate slope. The structural geology and climatic parameters of the study area have influenced the landform development and stream behavior in the watersheds. Hence, the present study is useful and essential for watershed management and planning rainfall harvesting.&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</em></strong></p> Kaiwan Kareemkhan Fatah, Shwan Seeyan, Shvan Jirjees ##submission.copyrightStatement## Tue, 28 Jul 2020 00:00:00 -0500 EFFECT OF TECTONIC SETTING ON DISTRIBUTION OF PELAGIC SEDIMENT UNIT (SHIRANISH FORMATION) IN ZAGROS FORELAND BASIN, IRAQI SEGMENT <p><strong><em>Shiranish Formation represents the uppermost Cretaceous pelagic sediment unit of the Iraqi segment within the western Zagros fold and the thrust belt. The occurrence of the formation governed by the northern edge of the Neabo-Arabian plate`s tectonic activity and the distribution has now been interpreted according to the modern tectonic concept of the foreland basin system. Field data and Isopach map have shown that two main basins existed on both sides of the Forebulge (Qamchuqa Formation). Currently, the first one has extended north west-southeast within the foredeep depozone, while the second one, which represents the Backbulge Depozone. The influence of the tectonic rise of the Forebulge Depozone leads to a non-existing pelagic sediments unit of the Shiranish Formation in the area restricted from northwest Amadiya town (the south limb of Mateen Anticline) towards southeast areas (Gara Anticline), thereafter to Aqra areas. Thus, the absence of the formation in the Shikhan area (e.g.) refers to inhomogeneity on the backbulge basin causing exposed or submerged areas during the age of upper Cretaceous.</em></strong></p> Rabeea KH. 1Rabeea Kh. Znad, Saddam Essa Mostafa, Mahmood A.H. Al-Sumaidaie ##submission.copyrightStatement## Tue, 28 Jul 2020 02:52:49 -0500 EVALUATION STRESS FIELD AND TECTONIC REGIME IN MID-EASTERN IRAQ-WESTERN IRAN FROM THE INVERSION OF MOMENT TENSOR FOCAL MECHANISM DATA <p><strong><em>The estimation of the stress-field direction from focal mechanism of an earthquake is a pertinent tool to understand crustal mechanics and earthquake habit. The main aim of this study is to infer the stress pattern of the mid-eastern Iraq - western Iran region. The study area is situated between latitudes 33.59°–34.93°N and longitudes 45.44°–46.39°E. Active stressed inversions of 102 moment tensor focal mechanisms data were used to rating the present day stress field. These data are subdivided into four regional subsets (circles) as a function of their geographical location and tectonic setting. The regional principal stress axes (σ1, σ2, and σ3) were inferred using right dihedron and rotational optimization methods by the formal stress inversion method. The results showed that there are spatial differences in the tectonic stress field, proportionate with fault orientations and faulting mechanisms. Thus, five stress regime categories are presented for the study area. It turns out that the prevailing tectonic systems are thrust faulting (50.98 %), strike-slip faulting</em></strong> <strong><em>(29.40 %), and unknown or oblique faulting (13.70 %); while the rest of the tectonic systems are less present thrust with strike-slip faulting (4.90 %), and normal with strike-slip faulting (0.98 %). The orientation of the maximum horizontal stress has a general directional trend towards NW-SE and NE-SW with local deviations related to the main predominant geological structures. Quality stress classifications were determined for the four groups’ areas and were of B and C quality. The local extensional tectonic environment between strike-slip fault systems possibly it's the reason there are some normal faults. Finally, we note that the spatial differences of the tectonic regime and the stress field are compatible with the neotectonic stress field that is identified from focal mechanism data.</em></strong></p> Hasanain jasim mohammed, Ali M. Al-Rahim ##submission.copyrightStatement## Tue, 28 Jul 2020 02:53:58 -0500