The Lesser Zab River, in the northeast of Iraq and northwest of Iran, is the largest tributary inside Iraq supplying water to the Tigris River. The majority of the basin lies inside Iraq. The ...important goals of this study are to estimate the erodibility and flash flood hazard of the Lesser Zab River Basin (LZRB). The present research highlights sub-basins that should be prioritized for conservation and flood risk schemes. The morphometric analysis reveals that the most important sub-basins are Sb1 and Sb2, in terms of water contribution to the main river. They are characterized by higher stream order, larger area, high elevation, low drainage density, low drainage texture, and low relative relief. Because of the relatively high relief in the upper part of the LZRB, the sub-basins are characterized by low drainage density, which indicates more surface runoff compared to the main basin in the lower part. The very fine drainage texture in the upper part of the LZRB reflects low infiltration and higher runoff relative to the lower part. The sub-basins in the upper part of the LZRB, which have a low bifurcation ratio, produce flood hydrographs with marked discharge peaks, while the sub-basins in the lower part, which have high ratios, produce low peaks over a long time period. Various morphometric parameters have been used for each sub-basin to calculate compound parameters for the final ranking of the sub-basins. Based on utilization of morphometric parameters for the erodibility hazard assessment, sub-basins were divided into seven prioritization classes: critical, very high to critical, high to very high, medium to high, low to medium, very low to low, and lowest. Furthermore, the resultant hazard map indicates that 18 sub-basins have moderate to low risk of flash flooding and 29 sub-basins have low possibility of flash flooding.
On-going monitoring of deformation of dams is critical to assure their safe and efficient operation. Traditional monitoring methods, based on in-situ sensors measurements on the dam, have some ...limitations in spatial coverage, observation frequency, and cost. This paper describes the potential use of Synthetic Aperture Radar (SAR) scenes from Sentinel-1A for characterizing deformations at the Mosul Dam (MD) in NW Iraq. Seventy-eight Single Look Complex (SLC) scenes in ascending geometry from the Sentinel-1A scenes, acquired from 03 October 2014 to 27 June 2019, and 96 points within the MD structure, were selected to determine the deformation rate using persistent scatterer interferometry (PSI). Maximum deformation velocity was found to be about 7.4 mm·yr−1 at a longitudinal subsidence area extending over a length of 222 m along the dam axis. The mean subsidence velocity in this area is about 6.27 mm·yr−1 and lies in the center of MD. Subsidence rate shows an inverse relationship with the reservoir water level. It also shows a strong correlation with grouting episodes. Variations in the deformation rate within the same year are most probably due to increased hydrostatic stress which was caused by water storage in the dam that resulted in an increase in solubility of gypsum beds, creating voids and localized collapses underneath the dam. PSI information derived from Sentinel-1A proved to be a good tool for monitoring dam deformation with good accuracy, yielding results that can be used in engineering applications and also risk management.
The Lesser Zab River (LZR), the largest tributary in Iraq, with a catchment area of about 20,000 km
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, and majority of its basin lying in Iraq, drains into the Tigris River. It runs through highly ...folded and faulted igneous and metamorphic zone in the northeastern part of Iraq. We studied the heavy minerals in recent sediments of the Lesser Zab River Basin (LZRB) to determine their mineralogies, assemblages pattern, distribution manner, spatial variability, microtexture, provenance, and tectonic setting. We analyzed 24 sediment samples for heavy mineral assemblage determination, using the standard petrographic method. Scanning Electron Microscopy was used to determine the morphology of the grains of selected heavy minerals. Heavy minerals identified in the studied sediments include: dark color such as magnetite, ilmenite, hematite, and goethite; and transparent minerals represented by hornblende, tremolite–actinolite; pyroxenes, epidotes, zircon, tourmaline, rutile, garnet, staurolite, kyanite, and layered minerals assemblage such as muscovite, chlorite, biotite, and phlogopite. The studied sediments are considered immature, because they have the lowest concentration of ultrastable minerals compared to unstable heavy minerals, which confirms that the surface sediments of LZR and its sub-basin tributaries were deposited in an active continental-margin tectonic setting.
There is a limited availability of fresh groundwater in the western part of Iraq due to the aridity of the region, and new water supplies are required to meet the demands of potential industrial, ...mining, and agricultural projects. Consequently, the factors that influence the quality, availability, and distribution of fresh groundwater in the region were assessed by combining hydrogeological, geophysical, and remote-sensing data within a GIS environment. For this purpose, the Shuttle Radar Topography Mission elevation data, geophysical data (gravity and magnetic), and hydrogeological database were used in an integrated approach. It was concluded that both a regionally extensive, deep intergranular aquifer and shallow-fractured and karstified carbonate aquifers have the potential to contain fresh groundwater in the region. It was inferred from the hydrochemical statistics that the main factors controlling groundwater chemistry are the dissolution of evaporite minerals and the weathering of carbonate rocks. Gravity (measured and satellite) data and magnetic data were processed and interpreted to identify the locations and characteristics of subsurface structures. Source Parameter Imaging was applied to calculate depth to the magnetic basement map from gridded magnetic data. The decompensative anomaly maps showed that zones with fresh groundwater are distributed on gravity lows which coincide with areas with a large depth to basement. Most of the fresh groundwater zones in the region are distributed between the pre-Tertiary and Tertiary axes of the Ha’il Arch due to increased recharge along this structure caused by intense fracturing. The extension of the gravity high outside the Iraq territory may suggest similar freshwater zones of groundwater occur in Syria, Jordan, and Saudi Arabia.
During the past few decades, rare earth elements (REEs) have gained enormous attention in geochemical studies worldwide as a result of their important role in the manufacturing of high-tech ...equipment. REEs in river sediment have been widely used for provenance determination and in geochemical studies of continental crust, rock and sediment environments, and anthropogenic pollution. This study aims to elucidate the origin and tectonic setting of Little Zab River Basin (LZRB) sediments by examining 23 fluvial sediment samples of rare earth elements (REEs) collected from both the primary river and the inter-sub-basin regions during the rainy or high-flow season. The ICP-MS method was employed to analyze all samples to identify and assess the compositions of REEs. A fraction of the river sediments, smaller than 2 mm, which is more representative and more homogeneous, was used to carry out geochemical analysis. REE concentrations in the Little Zab River (LZR) and the upper parts of the LZRB were generally higher than those in the lower parts. The concentration of REEs in nearly all samples was lower than that of the North American Shale Composite (NASC), and the Upper Continental Crust (UCC), except for the sub-basin sediment Sbs2, which was higher than these references; also, the sediment sample Zrs4 was slightly higher than NASC. Light rare earth elements (LREEs) display enrichment relative to heavy rare earth elements (HREEs) with a range between 7.15 μg/g and 12.37 μg/g for LZR samples and between 5.95 μg/g and 13.03 μg/g for the sub-basin samples. The REE discrimination diagrams, along with the chondrodite-normalized pattern of the studied sediments, confirm that the sediment is predominantly sourced from the alkaline basaltic unit of the late Cretaceous Walsh group of an arc tectonic affinity.
The increasing world population and the growing quantity of solid waste have become a challenging problem facing governments and policy makers because of the scarcity of suitable sites for new ...landfills and the negative perception of these sites by the people. This study aims to evaluate the performance of different Multi-Criteria Decision-Analysis (MCDA) approaches using remote sensing and Geographic Information System (GIS) data for identifying suitable landfill sites (LFSs). We evaluated the methodologies used by various investigators and selected appropriate ones as suitable sites for Municipal Solid Waste (MSW) landfill in the Tanjero River Basin (TRB) in the Iraqi Kurdistan region. We applied Boolean Overlay (BO), Weighted Sum Method (WSM), Weighted Product Method (WPM), Analytic Hierarchy Process (AHP), and Technique for Order Performance by Similarity to an Ideal Solution (TOPSIS) to allow combined use of 15 thematic layers as predictive factors (PFs). In this study, we applied the Topographic Position Index (TPI) for the first time to select MSW LFSs. Almost all methods showed reliable results and we identified eight suitable sites situated in the western part of the TRB having total area of ~18.35 km2. The best accuracy was achieved using the AHP approach. This paper emphasizes that the approach of the used method is useful for selecting LFSs in other areas, which are located in similar environments.
Soil loss is one of the most important causes of land degradation. It is an inevitable environmental and socio-economic problem that exists in many physiographic regions of the world, which, besides ...other impacts, has a direct bearing on agricultural productivity. A reliable estimate of soil loss is critical for designing and implementing any mitigation measures. We applied the widely used Revised Universal Soil Loss Equation (RUSLE) in the Khabur River Basin (KhRB) within the NW part of the Zagros Fold and Thrust Belt (ZFTB). The areas such as the NW Zagros range, characterized by rugged topography, steep slope, high rainfall, and sparse vegetation, are most susceptible to soil erosion. We used the Digital Elevation Model (DEM) of the Shuttle Radar Topography Mission (SRTM), Tropical Rainfall Measuring Mission (TRMM), Harmonized World Soil Database (HWSD), and Landsat imagery to estimate annual soil loss using the RUSLE model. In addition, we estimated sediment yield (SY) at sub-basin scale, in the KhRB where a number of dams are planned, and where basic studies on soil erosion are lacking. Estimation of SY will be useful in mitigation of excessive sedimentation affecting dam performance and watershed management in this region. We determined the average annual soil loss and the SY in the KhRB to be 11.16 t.ha−1.y−1 and 57.79 t.ha−1.y−1, respectively. The rainfall and runoff erosivity (R factor), slope length (L factor), and slope steepness (S factor), are the three main factors controlling soil loss in the region. This is the first study to determine soil loss at the sub-basin scale along with identifying suitable locations for check dams to trap the sediment before it enters downstream reservoirs. The study provides valuable input data for design of the dams to prevent excessive siltation. This study also aims at offering a new approach in relating potential soil erosion to the actual erosion and hypsometric integrals.
We report on a precision measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: A(PV) = -131 +/- 14(stat) +/- 10(syst) x 10(-9), leading to the ...determination of the weak mixing angle sin2(thetaW(eff) = 0.2397 +/- 0.0010(stat) +/- 0.0008(syst), evaluated at Q2 = 0.026 GeV2. Combining this result with the measurements of sin2(thetaW(eff) at the Z0 pole, the running of the weak mixing angle is observed with over 6sigma significance. The measurement sets constraints on new physics effects at the TeV scale.
This study aims to assess the potential of several ancillary input data for the improvement of unsupervised land cover change detection in arid environments. The study area is located in Central Iraq ...where desertification has been observed. We develop a new scheme based on known robust indices. We employ Landsat (multispectral scanner, thematic mapper, and enhanced thematic mapper) satellite data acquired in 1976, 1990, and 2002. We use the Normalized Deferential Vegetation Index, Normalized Differential Water Index (NDWI), Salinity Index (SI), and Eolian Mapping Index. Two new equations were applied for the SI and the NDWI indices. Validation was performed using ground truth data collected in 16 days. We show that such an approach allows a robust and low-cost alternative for preliminary and large-scale assessments. This study shows that desertification has increased in the study area since 1990.
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