DISTRIBUTION OF SOME HEAVY METALS IN THE RECENT SEDIMENTS OF AL-NASIRIYA AREA, MESOPOTAMIA PLAIN, SOUTH IRAQ

Abstract

During the period 15 March to 15 May 2011, 436 surface soil samples have been collected systematically based on the grid net in Al-Nasiriya Quadrangle (sheet NH-38-3, scale 1: 250 000), Mesopotamia Plain, and analyzed for Cr, Ni, Pb, Zn, Co, Cu and U, to re-evaluate the environmental conditions and concentration of the analyzed elements in the soil to detect any pollution, and to determine background levels and distribution of heavy metals in the studied area. The mineralogical analysis shows that for non clay minerals, quartz is the most abundant mineral, followed by calcite, feldspar, halite, and gypsum. For clay minerals; the most abundant mineral is montmorillonite, followed by palygorskite, illite, and kaolinite. The geochemical results show that the distribution and concentration of the heavy metals in the studied soils is within the average concentration given for the reported world soils of arid and semi arid regions, and the soil of the studied area is still free from pollution, except Pb in some local areas, which shows higher concentrations than those reported for world soils. In general, the concentrations of Cr, Ni, and Co are high, which is mainly due to the influence of igneous and sedimentary complexes in Turkey and Syria, derived by the Euphrates River and Injana and Dibdibba formations inside Iraq, as well as the clastics derived from northeast Iraq by the Tigris River and its tributaries, which show their influence in the Mesopotamia part of the river basin.