Mineralogy of Sand Dune Fields around Hor Al-Dalmaj Between Wasit and Al-Qadesiyah Governorates - Central Iraq

Abstract

Vast percentage of the Hor Al-Dalmaj area is covered with sand dunes fields due to desertification. Therefore, it is vital to research these dunes to limit their bad action on the natural environment by defining the mineralogical composition of these sand dunes deposited around Hor Al-Dalmaj lake between Wast and Al-Qasisiyah Governorates to determine the provenance or the source of these dunes. Barchan and Nabkha dunes represent the main types that are recognized. The dimensions of barchan dunes are recognizing by a height range of about 0.5 to 3m, with lateral extension ranging from 2 to 15m and longitudinal extinction ranging from 3 to 15m. While the dimensions of nabkha dunes range from 10 cm to 2m in length and 15cm to 2m high. According to the major wind direction, these dunes are extended from North West to south-east. The mineralogical investigation reveals that the light minerals of studied dunes consist mainly of quartz, feldspars and various rock fragments such as carbonate, chert, mudstone, evaporate, igneous, and metamorphic rocks. The most frequent heavy minerals are opaque, chlorite, pyroxenes, amphiboles, muscovite, biotite, zircon, epidotes, garnet, tourmaline, rutile, kyanite, and staurolite. The source of these sediments is recent sediment that has formed in river terraces, flood plain and Quaternary deposits in the Mesopotamian Plain, and the outcrops of the ancient sedimentary formations in the north northwestern, west, and southwestern Iraq.