Sedimentological, Mineralogical, and Geochemical characters of the Tigris River floodplain sediment in the Al-Alam area-Tikrit, Northern Iraq

Abstract

     The mineralogical investigation, geochemical analysis, and grain size calculation were carried out for floodplain sediment in the Tigris River to identify the properties of the sediment. The average values of the three main sediment classes, very fine sand, silt, and clay are 9.67, 62.53 and 27.80%, respectively. The silt size fraction was predominant. The classification and nomenclature of surface sediment types from the floodplain of the Tigris River are sandy-silt and mud, and they are the dominant sediment. Statistical parameters of grain size analysis refer to the average of the median values 3.74 Φ very fine sand; mean in average 6.16 Φ coarse silt; standard deviation evident by average 1.30 Φ poorly sorted, skewed; in average -0.14 negatively skewed, and the average of Kurtosis 2.80 very leptokurtic. The samples analysed by the XRD technique revealed clay minerals (chlorite, illite, montmorillonite, and kaolinite) and non-clay minerals (quartz, feldspar, calcite, and dolomite). The heavy minerals identified as species were zircon, tourmaline, rutile, garnet, olivine, hornblende, pyroxene, kyanite, and magnetic particles. The concentration of major oxides by geochemical analysis indicates a high content of SiO₂ and CaO in the floodplain of the Tigris river.