Assessment of mineralogical and chemical properties of airborne dust in Iraq

Abstract

The mineral composition and chemical and physical analysis of dust particles are essential to assess the potential impacts of dust on climate, environment, soil and health. The aims of this study are to give an overview of the mineralogical and chemical properties of dust storms over Iraq. Also, this study aims to identify potential sources of dust storms over Iraq. The results of particle size analysis showed that clay and silt particulates form an average of 86.9% of a dust storm, whereas sand particles represent an average of 13.2% of all dust samples. The physical analysis of dust samples revealed that low percentages of sand occur in the north region, but they are high in the western and central regions. The results of XRD analysis suggest that kaolinite, gypsum, albite, quartz and calcite were the major mineral dust components. However, lower amounts of palygorskite, microcline, dolomite, illite, chlorite and halite were detected in some station samples. The XRF analysis suggested that Ba, Sr and Cl were the main trace element components in the airborne dust samples. In addition, the chemical analysis of dust samples revealed that high percentages of Zn and Pb occur in the eastern and central regions. The results of HYSPLIT backward trajectories analysis of air parcels revealed that the potential sources of dust storms were the Syrian Desert, North Africa Desert, An-Nafud Desert in Saudi Arabia, the dry lands in south-western Turkey and southwest Iran, and the alluvial plain, Al Jazeera and Western Deserts in Iraq.